Dermatologic diseases of the external ear

Clinics in Dermatology (2014) 32, 141–152

Dermatologic diseases of the external ear Sedat Öztürkcan, MD a,⁎, Serap Öztürkcan, MD b a

Department of Otolaryngology and Head and Neck Surgery, Atatürk Research and Training Hospital of Katip Çelebi University b Department of Dermatology, Medical Faculty of Celal Bayar University

Abstract The external ear is composed of the auricle (pinna) and the external auditory canal. Both of these structures contain elastic cartilage (except the earlobe) and a small amount of subcutaneous fat, which are covered by skin. The skin of the cartilaginous canal contains hair cells, sebaceous (lipidproducing) glands, and apocrine (ceruminous) glands; this is in contrast with the osseous canal, which contains neither glands nor hair follicles. The auricle is susceptible to environmental influences and trauma. Due to its exposed locale, the ear is particularly vulnerable to the effects of ultraviolet light and, consequently, to preneoplastic and neoplastic skin lesions. The ear also has a sound-receiving function and a location that is both visible and aesthetically obvious, thereby drawing considerable attention from the patient. Dermatologic diseases on the external ear are seen in a variety of medical disciplines. Dermatologists, otorhinolaryngologists, family practitioners, and general and plastic surgeons are regularly consulted about cutaneous lesions on the ear. These lesions can be grouped into three main categories: (1) infectious; (2) tumoral; and (3) noninfectious inflammatory. The purposes of this contribution are to review various dermatologic diseases of the external ear and to update current diagnosis and treatment information related to these conditions. © 2014 Elsevier Inc. All rights reserved.

Dermatologic diseases of the external ear are seen in a variety of medical disciplines. Dermatologists, otorhinolaryngologists, general practitioners, and general and plastic surgeons are regularly consulted regarding cutaneous lesions on the ear. The external ear is composed of the auricle (pinna) and the external auditory canal. Both of these structures contain elastic cartilage (except the earlobe) and a small amount of subcutaneous fat, which are covered by the skin and its adnexal appendages, including sebaceous glands, sweat glands, and hair. The external ear is attached to the periosteum, and it is poorly vascularized. The epidermis on the concave aspect lies on a very thin subcutis that is strongly attached to the auricular cartilage. The convex aspect of the

⁎ Corresponding author. Tel.: +90 54268876022; fax: +90 232 4484522. E-mail address: [email protected] (Sedat Öztürkcan). 0738-081X/$ – see front matter © 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.clindermatol.2013.05.036

outer ear has a thicker subcutis with a stronger layer of subcutaneous fat that causes a certain laxity and displaceability as compared with the concave side.1 The external auditory canal serves as a conduit for sound transmission to the middle ear and protects the middle and inner ear. Its average length is 2.5 cm. The lateral third is cartilaginous, whereas the medial two thirds are osseous. The skin of the cartilaginous canal contains hair cells as well as sebaceous (lipid-producing) and apocrine (ceruminous) glands; this is in contrast with the osseous canal, which contains neither glands nor hair follicles. Together, these three adnexal structures are called the apopilosebaceous unit, and they serve a protective function. Cerumen (ear wax) is a result of the secretions that are produced by the sebaceous and apocrine glands admixed with desquamated epithelial cells. In addition to physically protecting the canal skin, this acidic coating creates an inhospitable environment for pathogens while producing antimicrobial compounds such as lysozymes.2

142 The cerumen may mask existing diseases of the skin at the entrance to the external ear canal. In the presence of a ceruminal obstruction, an adequate assessment of the external auditory meatus should be done only after cleaning, which may uncover existing dermatosis. The auricle is susceptible to environmental influences and trauma. Because of its exposed locale, the ear is particularly liable to the effects of ultraviolet light and, consequently, to preneoplastic and neoplastic skin lesions. The ear also has a soundreceiving function and a location that is both visible and aesthetically obvious, thereby drawing considerable attention from the patient.2 The ear canal is a self-cleansing structure as the cerumen coat migrates laterally and sloughs externally. Instrumentation and excessive cleansing of the canal predisposes an individual to infection in two ways. First, the act of removing cerumen, even with the use of one’s own fingernail, may be traumatic, because it can abrade the canal skin and allow for the introduction of bacteria. Second, the removal of cerumen leads to the disruption of this protective barrier.3 The two most common organisms isolated from the external auditory canal of normal individuals are the Staphylococcus species (S auricularis, S epidermidis, and S capitis) and the Corynebacterium species (Turicella otitidis and C auris). The third most frequently recovered bacteria are the Streptococci and Enterococci group (Alloiococcus otitis). Together, these bacteria account for more than 90% of the normal flora in the external auditory canal.3 Dermatologic diseases of the external ear can be grouped into three main categories: (1) infectious; (2) tumoral; and (3) noninfectious inflammatory. Dermatologic diseases of the external ear are listed here.

S. Öztürkcan, S. Öztürkcan • Cutaneous horn • Lentigo maligna C. Malignant • Basal cell carcinoma • Bowen’s disease • Squamous cell carcinoma • Melanoma • Malignant adnexal tumors 3. Noninfectious inflammatory dermatologic diseases of the external ear • Cold injury of the external ear • Burn injury of the external ear • Seborrheic dermatitis • Contact dermatitis • Atopic dermatitis • Acne • Lupus erythematosus • Psoriasis

Infectious dermatologic diseases of the external ear Otitis externa refers to a spectrum of infections of the external auditory canal and the auricle. It is a common condition, and it affects between 5% to 20% of the patients who visit otolaryngology clinics.4 It may be classified on the basis of etiology, location, and time course of the illness. These different classifications include acute diffuse otitis externa, acute localized otitis externa, chronic otitis externa, and otomycosis.2–8

Acute diffuse otitis externa 1. Infectious dermatologic diseases of the external ear: • Acute diffuse otitis externa • Chronic otitis externa • Furunculosis (acute localized otitis externa) • Otomycosis • Lymphocytoma • Auricular chondritis and perichondritis • Lupus vulgaris • Herpes zoster oticus 2. Tumoral dermatologic diseases of the external ear A. Benign • Seborrheic keratosis • Granuloma fissuratum • Keloid • Chondrodermatitis nodularis helicis chronicus • Melanocytic nevus • Blue nevus • Cylindroma • Benign adnexal tumors • Auricular appendages • Osler-Weber-Rendu disease B. Premalignant • Actinic keratoses

Acute diffuse otitis externa is a bacterial infection of the ear canal that is caused by a break in the normal skin and cerumen protective barrier in the presence of elevated humidity and temperature. It is commonly known as “swimmer’s ear,” although anything that disrupts this protective lipid layer can lead to the introduction and proliferation of bacteria.5 Trauma from cleaning the ears with fingernails or cotton swabs has been identified as the most common predisposing factor locally. Other predisposing factors include inherited narrow ear canals and nonatopic eczema. Pain (70%), itchiness (60%), deafness (32%), and fullness (22%) are the cardinal symptoms of this condition.6 Signs on examination include erythema, edema, purulent otorrhea, and crusting of the canal wall skin. A gentle tug of the auricle upward and backward usually causes pain, and this distinguishes otitis externa from otitis media.3,7 The clinical course of otitis externa is divided into three stages: preinflammatory, acute inflammatory, and chronic inflammatory. The acute inflammatory stage is further divided into categories of mild, moderate, and severe. The preinflammatory state is characterized by itchiness, edema, and a sensation of fullness. The acute stage is accompanied

Dermatologic diseases of the external ear by pain and auricular tenderness. As the infection progresses from mild to severe, the itchiness, pain, and auricular tenderness are all intensified. The canal becomes more edematous and erythematous. The secretion, which is initially clear and odorless, will turn into a thick, profuse, and seropurulent exudate. During the severe stage, the lumen becomes obliterated as a result of the increasing edema and the seropurulent material. The patient complains of intense pain, especially with chewing or tragal manipulation. Fever, periauricular edema, and cervical lymphadenopathy may also be present.2,4,6 Pseudomonas aeruginosa, S epidermidis, and S aureus are the three most common pathogens isolated locally from acute diffuse otitis externa.8 The same study also identified the Microbacterium species as important pathogens in acute otitis externa; these pathogens are members of the Corynebacterium group, which includes M otitidis and M alconae. The culturing of the canal is usually only required in recalcitrant cases, where it may assist with the selection of antibiotic therapy. The key to successfully managing external ear infections is regular and meticulous aural maintenance. In the general practice setting, commonly used techniques include syringing or swabbing the ear canal with cotton-tipped applicators. The best method is probably microsuction, because it allows for the direct visualization of the ear canal and the complete clearance of any debris. The only limitation is the need for a microscope. If the canal is obliterated by edema and debris, a Pope wick is inserted to stent the canal and to allow for the application of antibiotic/steroid eardrops. The wick is generally removed 24 to 72 hours later, although it can be left in the canal for up to 1 week. After the ear is cleaned, an antibiotic/steroid eardrop is administered for 1 week. Topical antibiotics and steroids are based in an acidic solution to inhibit bacteria growth; many also contain glycerol, which acts as a desiccant. The major adverse reaction to the use of an acidic agent is burning on application, which may affect the patient’s compliance. Ophthalmic preparations are less acidic than otic preparations and may be better tolerated by these patients. These agents also have low viscosity, thereby allowing for improved penetration in narrow lumens.2 Eardrops that contain gentamicin or polymyxin appear to be most effective against the three most common local bacteria. Ciprofloxacin/ofloxacin otic solution is a topical formulation that has a wide spectrum of activity against most common ear pathogens.9 Although some organisms may exhibit resistance to antibiotics in vitro, the high concentration of antibiotics in topical antibiotic preparations will be lethal to those with resistance, provided that the topical solution can penetrate to infected tissues.8 For severe cases in which cellulitis is present, systemic antibiotics are indicated. Analgesia is also required for pain control. Patients are advised to resist digital manipulation, to avoid swimming during the treatment period, and to prevent water from entering the ear canal while taking a shower or a bath. A few of the common differential diagnoses include malignant otitis externa, bullous external otitis, granular

143 external otitis, furunculosis, and dermatoses such as seborrheic dermatitis. Another important differential diagnosis is carcinoma of the external auditory canal, which may present as infection; during its earliest stages, it is often mistaken for infection and inappropriately treated.7 The persistence of infection and the presence of granulation tissue despite treatment will require a biopsy to exclude malignancy.

Chronic otitis externa Chronic otitis externa occurs when there is incomplete resolution of the acute infection or when there is persistent low-grade infection and inflammation for more than 3 months. There is less pain but more profound itching and persistent discharge. Examination reveals thickening of the canal skin of the ear canal with no wax. The chronic scaling and itching in the canal predispose the patient to manipulation of the canal, excoriation, and repeated episodes of acute otitis externa. With time, the canal becomes completely obliterated by the hypertrophic skin.2 The goal of treatment is to restore the external auditory canal skin to its original healthy state and to promote the production of cerumen.2 The treatment consists of frequent aural cleaning and the instillation of acidifying and drying eardrops (eg, vinegar and water, ethyl alcohol and water). We have also found the application of gentian violet to be a useful adjunct for the treatment of chronic otitis externa. The use of topical antibiotics and steroids may be required during acute exacerbations. Surgery is rarely indicated and is limited to enlarging and resurfacing the external auditory canal (ie, canalplasty).2

Furunculosis (acute localized otitis externa) The pathology of furunculosis is an infection of a hair follicle by S aureus. The main symptom is otalgia, and there is generally no otorrhea or deafness. The patient complains of pain during tugging the pinna and compression of the tragus. Examination reveals a localized swelling with surrounding erythema within the hair-bearing area of the external ear canal. If the furuncle is not pointing, an antibiotic-impregnated wick is inserted into the canal over the furuncle for about 3 to 5 days. If it is pointing, incision and drainage will be required. A course of antibiotics for a period of 1 week is also prescribed.2

Otomycosis Otomycosis, which is also known as fungal otitis externa, has been used to describe a fungal infection of the external auditory canal and its associated complications, which sometimes involve the middle ear. The prevalence of this condition is also related to the geographic area: otomycosis is most commonly present in tropical and subtropical humid climates. The extensive and sometimes unnecessary use of

144 antibiotic eardrops for the treatment of otitis media and otitis externa has been linked to an important increase in the prevalence of otomycosis. The secondary overgrowth of fungi is a well-known and recognized complication of the use of broad-spectrum antibiotics like quinolones.10,11 The most common fungal species isolated from temperate climates are Candida and Aspergillus.12 There are numerous forms of treatment, including topical preparations, systemic therapies, and office-based debridement. Although several options exist for the treatment otitis externa, the use of ototopical agents in the setting of open middle ear space created by tympanostomy tube insertion or tympanic membrane perforation continues to be debated. The use of few topical antifungals has persisted throughout time, including nystatin and the azoles family. The reviewed literature emphasized the importance of aural hygiene in addition to topical therapy for the treatment of otomycosis; ototopical medications work best after the removal of secretions and debris.13 The typical treatment regimens for the most commonly used agents in our practice are as follows. Ketoconazole cream or clotrimazole pomade is applied in the clinic directly onto the involved external auditory canal skin after the canal is cleaned under microscopic visualization. The application of this treatment is facilitated with a small syringe (1 or 3 cc) and an 18-gauge or larger intravenous catheter. The antifungal paste is held in place largely by its innate viscosity and the shape of the external auditory canal. The ear canal is inspected 2 days later, and residual cream or pomade is removed. A second application for persistent disease has been necessary in a few cases. To date, there is no U.S. Food and Drug Administration– approved antifungal otic preparation for the treatment of otomycosis. Many agents with various antimycotic properties have been used, and clinicians have struggled to identify the most effective agent for the treatment of this condition. Antifungal agents typically reach some popularity for a short period of time, until undesirable side effects are identified or until a new medication appears on the market.11

Lymphocytoma (lymphadenosis benigna cutis) Lymphocytoma can be an early manifestation of an infection with Borrelia burgdorferi, which is caused by the bite of a tick and which causes Lyme disease. Such an infection initially results in a characteristic rash (erythema chronicum migrans) located in the area of the tick bite. During the second stage, an intensely red-violet swelling of the earlobe is common. Infection with B burgdorferi is the cause of one third of all earlobe lymphocytomas, and it is has to be ruled out serologically when it is suspected. Two thirds of all cases are idiopathic. Antibiotic therapy consists of oral doxycycline treatment for 2 to 3 weeks. When the lesions do not improve with antibiotic treatment, pseudolymphoma is one possible differential diagnosis. Small lesions can be excised.14

S. Öztürkcan, S. Öztürkcan

Auricular chondritis and perichondritis Auricular chondritis and perichondritis are infections of the auricle. Clinically, the ear will appear erythematous and tender, and a fluctuant swelling is usually present. There is typically an inciting event (eg, piercing, surgery, trauma, wrestling, acupuncture) that is followed by an infection that results from the collection of blood or serum in the subperichondrial space. The most common organisms that have been found to be causative are S aureus, P aeruginosa, and Proteus species. The subperichondrial space must be surgically evacuated, and antibiotic therapy that consists of an antipseudomonal aminopenicillin or a fluoroquinolone will be given for a period of 2 to 4 weeks. As a result of recurring chondritis, persisting deformity of the ear’s cartilage can remain.14

Lupus vulgaris Lupus vulgaris is a persistent form of cutaneous tuberculosis that potentially involves the ear. Lesions are sharply defined and brown, with a gelatinous consistency on an erythematous base. Therapy involves a combination of antibiotics (ie, isoniazid, rifampicin, pyrazinamide, and ethambutol) given over a period of several months in addition to the surgical excision of necrotic tissue. Because tuberculosis is enjoying a renaissance in Western countries, the incidence of cutaneous tuberculosis will likely increase in the future.14

Herpes zoster oticus (Ramsay Hunt syndrome) Herpes zoster oticus also known as Ramsay Hunt syndrome; this is a rare complication of herpes zoster disease in which the reactivation of latent varicella zoster virus infection occurs in the geniculate ganglion of the facial nerve. The involvement of the facial nerve leads to otalgia, lower motor neuron homolateral facial paralysis, and vesicular eruptions in the auricle.15 Primary infection with varicella zoster virus usually occurs during childhood or adolescence and then remains latent. The reactivation of varicella zoster virus mainly occurs in adults. Ramsay Hunt syndrome is rare among children, and it affects both sexes equally. The mechanism of viral reactivation is not clear, although it may occur as a result of the failure of cellular immune defense. Incidence and clinical severity increase when the host’s cell-mediated immune system is compromised.15,16 There are three different clinical types of Ramsay Hunt syndrome that are based on the severity of the disease.4 The first and mildest form of the disease is herpes zoster auricularis, which manifests as pain, redness, and the formation of herpetic vesicles in the ear. With the second form of the disease, in addition to the herpetic lesions, facial paralysis occurs at any affected site of the head or neck. The

Dermatologic diseases of the external ear third form of the disease is accompanied by signs of eighth nerve involvement, which results in the above-mentioned symptoms.16 Ramsay Hunt syndrome classically begins with prodromal signs, such as severe and sharp pain around the ear, a red and swollen auricle, fever, and weakness. This is followed by the formation of herpetic vesicles on the auricle, the external ear canal, and sometimes on the tympanic membranes, the tongue, and the uvula within 3 to 4 days. Vesicles are generally involved at the affected sites. Peripheral facial paralysis exists in 60% to 90% of patients. Facial paralysis generally appears 2 to 3 days after a vesicular eruption. The appearance of the paralysis may sometimes be prolonged by up to 1 week. Vesicles are located on the same side as the facial paralysis. Signs of eighth nerve involvement (eg, nausea, vomiting, vertigo, nystagmus, tinnitus, hearing loss) may accompany the disease. In addition, fifth, sixth, ninth, or tenth cranial nerve involvement may occur in some patients as well. The involvement of the vestibulocochlear nerve leads to sensorineural hearing loss in 10% of patients and vestibular symptoms in 40% patients.15,16 The time of onset of the vesicles carries a prognostic importance. It has been reported that vesicular lesions appear in 19.3% of cases before facial paralysis; they appear simultaneously with facial paralysis in 46.5% of cases and after facial paralysis in 34.2% of cases. The onset of vesicular lesions before facial paralysis is considered a good prognostic factor.16 The most effective method for the treatment of Ramsay Hunt syndrome is still a combination of antiviral medications, which are used to prevent the replication of varicella zoster virus, and systemic steroids, which are used for their anti-inflammatory and antiedemic effects. The initiation of acyclovir (800 mg/d), valacyclovir (1 g three times daily), or famciclovir (500 mg three times daily)—particularly within the first 72 hours—is of great importance for the treatment of herpes zoster virus.15,16

Tumoral dermatologic diseases of the external ear We can classify the tumoral diseases of the external ear as benign, premalignant, and malignant.

Benign lesions Seborrheic keratosis (seborrheic wart, senile wart) Seborrheic keratosis is one of the most common nonmalignant tumors of the external ear. It appears as a light brown, mostly flat, sometimes exophytic papular lesion that originates from proliferative epithelial cells. Its spread increases with age, and it can potentially affect the whole ear, including the external auditory canal.1

145 Ultraviolet light exposure, human papillomavirus infection, hereditary factors, and the action of estrogen and other sex hormones are among the factors that have been suggested in the etiology of this disease. Secondary malignant changes may occur but are extremely rare.17 Treatment varies from pure trichloroacetic acid to cryotherapy to electrodessication. Especially irritated types of seborrheic keratosis can be misdiagnosed as squamous cell carcinoma, because they frequently have active cellular appearances and a downward proliferation of the active epithelial cells. Because of this situation, the physician will need to biopsy the lesion.1 Granuloma fissuratum (acanthoma fissuratum) Granuloma fissuratum is a reactive process of the skin that is usually caused by chronic trauma from ill-fitting eyeglass frames. The constant pressure of an ill-fitting frame nearly always leads to a unilateral, tender mass of granulation tissue that is skin colored to light red and located behind the auricle; this mass has an exophytic, elliptical growth pattern and a central notch. This lesion should be kept in mind because of its resemblance to malignant tumors. It is a benign differential diagnosis of basal cell carcinoma and squamous cell carcinoma, but it can often be managed readily with a correction of the ill-fitting eyeglass frame.18 Keloid Keloids are dermal fibrotic lesions that are considered aberrations of the wound healing process. They are included in the spectrum of fibroproliferative disorders, and they commonly affect the ears. Clinically dense dermal scar tissue projects above the surrounding skin, which is sometimes tender or pruritic. These lesions are common after small skin excisions, ear piercing, the drainage of auricular hematomas, the repair of other auricular traumas, or viral infection (eg, smallpox, varicella-zoster) or as secondary keloid formation after prior keloid excision. Although optimal conditions for the prevention of keloid formation are still unknown, the combination of excisional surgery and the placement of a silicone gel sheet over the wound surface with the application of light pressure is known to be advantageous.19 Chondrodermatitis nodularis helicis chronicus Chondrodermatitis nodularis helicis chronicus, which is also known as painful ear nodule or Winkler’s nodule, is a fairly frequent disorder that is characterized by the onset of painful inflammatory nodular lesions on the external edge of the helix, the antihelix, or the antitragus.20,21 At least one small, hemispherical nodule develops over a period of several months. The right ear is the usual site. The apex of the nodule is often covered in thin, pearly, pinkishgray, atrophic skin, and this is sometimes surrounded by an area of erythema. When the lesion ulcerates, a crust may form. These nodules are extremely painful, especially when they are touched or grazed, and they can prevent an affected

146 patient from laying his or her head on a pillow or even answering the telephone. This is the result of the hyperplasia of nerve fibers in the inflamed tissue.20,22 Although the cause of this condition is unknown, its onset is thought to be related to microtrauma, prolonged excessive pressure (lesions usually occur on the side on which the patient prefers to sleep), or chronic actinic damage.20 Complete surgical excision continues to be the definitive treatment of choice. Photodynamic therapy, the local application of topical steroids, antibiotic ointments, the intralesional injection of collagen, cryotherapy, curettage followed by diathermy, and carbon dioxide laser treatments have also been proposed.20,23 Melanocytic nevus Melanocytic nevi are benign neoplastic proliferations of nevus cells that can be classified as congenital or acquired.24 They are categorized into three subgroups according to their histological location, which may be junctional, compound, or intradermal.25 Melanocytic nevi in the external auditory canal are uncommon; the most common are intradermal nevi.26 Melanocytic nevi may be papillomatous, dome-shaped, pedunculated, or flat on top, and they are usually flesh colored, pink, or pigmented. Melanocytic nevi in the external ear canal can present with otalgia, foreign body sensation, aural obstruction, and conductive deafness, or they may cause the trapping of water within the external meatus and predispose the patient to recurrent attacks of acute otitis externa (some cases were asymptomatic and were found incidentally). The definitive diagnosis is made via the clinical appearance and with a histopathologic examination. The treatment of choice for a symptomatic nevus in the external auditory canal is complete excision. All melanocytic nevi should be excised (rather than biopsied) to rule out melanoma. There has been no recurrence reported in the literature.27,28 Blue nevus (nevus bleu, Jadassohn-Tieche nevus) A blue nevus is a variant of a common benign mole, which can be clinically misdiagnosed as melanoma. The lesion is a gray-blue to dark-blue macule with a smooth surfaced that is composed of melanocytes. When multiple blue nevi are located in the head and neck, Carney's syndrome—a rare association of blue nevi with hypercortisolism and a variety of nonendocrine (myxomas) and endocrine tumors—should be considered. Solitary and stable lesions can be observed. A changing pigmented lesion should be biopsied to rule out the differential diagnosis of a malignant melanoma.14 Cylindroma (Spiegler's tumor, turban tumor) Cylindroma is benign, solitary or group-like, skin-colored or light red, bulging, protuberant tumor with a flat, shining surface. These tumors are usually located on the head and neck (ie, turban tumor), and they can potentially involve the ear. They most likely represent very primitive sweat gland

S. Öztürkcan, S. Öztürkcan tumors that originate in the eccrine or apocrine glands. Histologically they have apocrine, eccrine, secretory, and ductal features, but their exact cellular origin remains unknown. Surgical excision is the treatment of choice.14 Adnexal tumors (sweat gland tumors) Because the skin of the external auditory canal has a high concentration of ceruminal glands, it is susceptible to this already very rare type of benign and malignant tumor. Benign adnexal tumors include ceruminous adenomas and pleomorphic adenomas. They are best treated with wide local excision.14 Auricular appendages Auricular appendages are themselves harmless lesions. In very rare cases, they can be cutaneous manifestation of a complex disease. Goldenhar syndrome, Wildervanck syndrome, and Vertebral defects, Anal atresia, Cardiac defects, Tracheo-Esophageal fistula, Renal anomalies, and Limb abnormalities Association are very rare diseases that should be considered further. Surgical therapy is only performed in accordance with the specific wishes of the patient.14 Osler-Weber-Rendu disease Osler-Weber-Rendu disease, which is also called hereditary hemorrhagic telangiectasia, is an autosomal dominant disease that manifests itself with multiple punctuate hemangiomas and telangiectases on the auricles. Additional characteristics are epistaxis and mucocutaneous visceral arteriovenous malformations. Laser therapy with a longpulsed neodymium-doped yttrium aluminum garnet laser, a flash-pumped dye laser, or an intense pulsed light system has been described as effective.14

Premalignant lesions Actinic keratoses (solar keratoses, senile keratoses) Actinic keratoses are lesions that are induced by ultraviolet light and that are often located on the ear, especially on the helical rim. The most important causative factor is long-term sun exposure. Actinic keratosis is the initial lesion in a disease continuum that progresses to invasive squamous cell carcinoma. The average person with actinic keratosis is an elderly patient with fair skin and a history of excessive sun exposure. Other risk factors for actinic keratosis include being immunosuppressed or having certain genetic diseases (eg, xeroderma pigmentosum). Organ transplant patients who are taking immunosuppressive drugs will make up a larger group of the patients who will have actinic keratosis and squamous cell carcinoma.29 The most common clinical presentation of an actinic keratosis is a red, scaling papule or plaque on a sun-exposed area. There is no definite way to distinguish between an actinic keratosis and a squamous cell carcinoma without performing a biopsy. An increase in thickness, redness, pain, ulceration, and size may suggest a progression to squamous

Dermatologic diseases of the external ear cell carcinoma, but these are not absolute criteria. Histologically and clinically, there is a continuum and a progression between these two diagnoses that makes reliable distinction between the diseases almost impossible; one evolves into the other without any clear features to distinguish the two. It is thus impossible to predict the point at which an individual actinic keratosis will evolve into an invasive squamous cell carcinoma. Because it can be impossible to distinguish between actinic keratosis and some squamous cell carcinomas, treatment can be difficult. Many lesions that are thought to be actinic keratoses are actually squamous cell carcinomas that are then treated improperly. This forces the clinician to perform biopsies on lesions that are thought to be actinic keratoses that are not responding to treatment.29 The fact that many lesions being treated as actinic keratoses could really be early squamous cell carcinomas suggests that treatment should be aggressive and that patients should be monitored closely so that the eventual progression from actinic keratosis to squamous cell carcinoma may be stopped. Effective treatment options include curettage, photodynamic therapy, laser therapy, and topical 5-floururacil, diclofenac, colchicine, imiquimod, and retinoid application.29–32 Cutaneous horn (cornu cutaneum) Cutaneous horn is not a pathologic diagnosis. A variety of primary underlying processes that are benign, premalignant, or malignant can cause this lesion. The cutaneous horn is an excrescent lesion of conical morphology that is formed by the retention of the horny layer. Most cutaneous horns have a yellow-white color; they may be straight or curved and twisted, and they may vary from a few millimeters to several centimeters in length. They usually appear on skin surfaces that have been exposed to solar radiation.33 Treatment depends on the type of lesion and its malignant potential. It is essential to take a biopsy that includes the base of the horn with epidermis and dermis to give the pathologist the best material for assessment. In cases of benign lesions, the biopsy may be both diagnostic and therapeutic; with large seborrheic keratoses, further treatment could be required. Any residual lesion can be treated with cryotherapy, unless the thick keratin horn is still present as a result of the risk of the insulating effect of the compact keratin. For malignant tumors, complete surgical excision with appropriate margins is usually required.33 Lentigo maligna (Hutchinson's freckle) Lentigo maligna is a slow-growing, noninvasive melanoma in situ. Little attention is paid to this insidious lesion, which can potentially become an invasive lentigo maligna melanoma with a conversion rate of 33% to 50%.34 The estimated lifetime risk of lentigo maligna progressing to lentigo maligna melanoma is 5%.35 The lesion begins as an unevenly pigmented and irregularly bordered brown to black macule that slowly extends over the course of time. Nonsurgical therapies such as cryosurgery, radiotherapy, electrodessication and curettage, laser surgery, and topical

147 medications have been described in the literature, with a recurrence rate that ranges from 20% to 100% at 5 years.34 Whenever excision by means of micrographic-controlled surgery or chemosurgery is possible, it should be the preferred method of treatment, because these involve the lowest recurrence rate (4% to 5%) and the best form of margin control among all described forms of therapy.35

Malignant lesions Basal cell carcinoma (basalioma, basal cell epithelioma) Basal cell carcinoma (BCC) accounts for 90% of all malignant cutaneous lesions in the head and neck region, and it is the most common type of skin cancer that involves the ear. It makes up one fifth of neoplasms that involve the ear and the temporal bone. The vast majority of BCC of the ear occurs on the auricular helix and the periauricular area, with 15% arising in the external auditory canal.14 BCC of the ear presents as an aggressive phenotype in the majority of cases for both men and women, and it occurs much more frequently among men.36 BCCs of the external auditory canal are rare and less frequent than squamous cell carcinomas, but they are associated with a relatively poor prognosis.37 Chronically sun-exposed parts of the body develop a larger proportion of BCCs. Nearly 50% of people who are routinely treated for BCC developed multiple primary BCC during 10 years of observation.14,38 Five different clinical forms are distinguished in the literature: nodular-ulcerative, pigmented, cystic, superficial multicentric, and morphea-like. The most common type is the nodular-ulcerative form. The lesion is a flesh-colored scaling papule, mostly erythematous to pink and sometimes pigmented, with a surrounding capillary network. It has a pearly border, and it may have a central ulcer. The nodularulcerative form may infiltrate the cartilage.14 Although metastases of BCC are extremely rare, the invasive character of the tumor can cause extensive local tissue destruction. The most successful therapy for BCC is micrographic-controlled surgery, which is a two-stage operation. BCC that is found on the auricular or preauricular area has the highest rate of recurrence after treatment by excisional surgery, radiation, cryosurgery, curettage, or electrodessication, all of which are alternative forms of treatment.14 BCC of the ear demonstrates a more aggressive phenotype as compared with BCC at other body sites.34 BCCs of the external auditory canal behave, even after radical surgery, as aggressive tumors and are associated with very poor prognoses.37 This information can help to guide physicians and ensure that these tumors are adequately biopsied and treated. Bowen’s disease (carcinoma in situ, squamous intraepidermoid neoplasia) Bowen’s disease is an intraepidermal carcinoma in situ that presents as the preinvasive form of squamous cell

148 carcinoma. It is strongly associated with sun exposure, and lesions are found in up to 83% of individuals who are infected with human papillomavirus type 16. The lesions are erythematous, scaly patches or plaques with irregular borders that can occur anywhere on the skin. They can become hyperkeratotic, crusted, fissured, or ulcerated, and they generally occur in sun-exposed areas. Bowen’s disease is a carcinoma in situ of the epidermis and therefore potentially malignant. Progression to invasive squamous cell carcinoma has been noted in approximately 10% of Bowen’s lesions, so these should be completely excised when possible via micrographic-guided surgery.38 Topical imiquimod or 5-floururacil, cryotherapy, photodynamic therapy, radiography, Grenz-ray therapy, cauterization, and diathermy coagulation therapy have been described as being effective for this condition, but these treatments lack micrographic control.39–41 Squamous cell carcinoma Squamous cell carcinoma can arise anywhere on the outer ear and potentially involve the middle ear and the lateral skull base. This type of tumor mostly originates on the helix and the antihelix margin, where the skin receives the greatest actinic exposure. Patients with this condition present during their fifth and sixth decades of life, whereas lesions that originate primarily from the external auditory canal generally present 10 to 15 years earlier. Sun exposure, fair complexion, cold injury, radiation exposure, and chronic infection as well as an association with human-papillomavirus–induced viral carcinogenesis are among the predisposing factors. The tumor is a scaly, indurated, irregular maculopapular lesion that demonstrates an exophytic or endophytic growth pattern with a hyperkeratotic or ulcerating surface, sometimes with serosanguineous exudates.42 Squamous cell carcinoma lesions on the nose and the ear have the highest rates of recurrence, perhaps because of their association with embryonic fusion planes; therapy should therefore be aggressive. A complete excision by means of micrographic surgery with tumor-free margins is necessary for a successful outcome.43 It is also important to look for possible regional lymph node metastases, which portend a poor prognosis. Locoregional metastases follow the lymphatic drainage patterns, which include the parotid and upper cervical nodes.44 Melanoma (malignant melanoma) Approximately 20% of all primary melanomas are located on the head and neck; of these, 7% to 14% are located on the ear’s helix and antihelix. Peripheral parts of the ear are more frequently affected. The most accepted theory for this phenomenon is the asymmetric ultraviolet dosage that this area received in countries with a predominantly white population as a result of cars being driven on the left-hand side of the road. A male predisposition of 61.5% to 90.5% has been reported in the literature, with an additional predisposition found among fair-skinned individuals.45,46

S. Öztürkcan, S. Öztürkcan A melanoma begins as a macular lesion with variable pigmentation and an uneven and irregular border; there is then a sudden increase in the size, induration, and darkening of the lesion. The thin layer of subcutaneous tissue contributes to the distinctive invasiveness (and, therefore, the bad prognosis) of melanoma of the ear. Key pathologic prognostic features of auricular melanomas include the histologic subtype, the tumor thickness, the level of invasion, and the presence of ulceration.47 The overall survival rate among patients with melanoma of the ear depends primarily on the tumor thickness and Clark’s level of invasion. Therapy involves surgery and, in some instances, adjuvant therapy. Recommended excision margins are 10 to 20 mm for primary nodular melanoma or superficial spreading melanoma and 5 mm with complete three-dimensional histology of the excision margins for lentigo maligna melanoma. The World Health Association requires a safety margin of 5 mm for melanoma in situ and of 20 mm for melanoma that are more than 2.1 mm in vertical thickness. Recent studies have shown that margins of more than 10 mm involve the lowest risk of recurrence.47 This is an aggressive tumor type with a tendency to spread to both regional lymph nodes and distant sites. One third of all patients who present with auricular melanoma also have cervical lymph node involvement.48 Malignant adnexal tumors Malignant adnexal tumors include adenoid cystic carcinoma, mucinous carcinoma, cylindrocarcinoma, porocarcinoma, spiradenocarcinoma, and adenocarcinoma. These tumors should be treated via an initial aggressive wide en bloc surgical resection with a primary lateral or subtotal temporal bone resection that is stage dependent and combined with a parotidectomy and a neck dissection.14

Noninfectious inflammatory dermatologic diseases of the external ear Cold injury of the external ear (frostbite of the pinna) Cold injuries are a significant cause of morbidity among soldiers who are deployed in extremely cold climates. Most of these injuries take the form of frostbite of the extremities. Although the head and neck region are constantly exposed to the cold climate and chilly winds, second- and third-degree frostbite of these regions is uncommon. The tip of the nose and the pinna are commonly affected with frostnip, which is characterized by painful swelling and erythematous discoloration. Current methods that are used to treat cases of frostbite include gradual rewarming, anti-inflammatory drugs, hyperbaric oxygen, vasodilators, and surgical debridement. The role of unconventional treatment modalities in the form of topical applications of aloe vera extract has not been fully established, although scientific evidence exists to

Dermatologic diseases of the external ear support its protective role. The mechanism of action and the active ingredient responsible for the results remain debatable.49

Burn injury of the external ear The auricle is frequently injured during thermal injury of the head and neck because of its prominent position and its tissue composition. It is covered by skin but has no underlying subcutaneous tissue. This lack of subcutaneous tissue leaves the perichondrium and the cartilage with little protection. Chondritis is the most common early complication after a burn of the auricle.50,51 The treatment of auricular burns is similar to the treatment of burns in other locations. In most of patients, conservative treatment results in complete healing. Some authors support the use of silver sulfadiazine, which is typically delivered in a 1% cream. They also agree that systemic antibiotics and any pressure to the area should be avoided. Any areas of obvious third-degree burns should be debrided and grafted. Any tympanic membrane perforation should be treated with antibiotic/steroid drops.48 Topical mafenide acetate cream is recommended for its excellent eschar and cartilage penetration and its clinical efficacy for reducing the incidence of chondritis. Exposed cartilage must be covered with vascularized tissue.52 Favorable results in another study have been attributed to the following factors: early detection of chondritis, early surgical intervention, radical cartilage removal, meticulous postoperative care to prevent cross-infection, and the avoidance of any pressure being placed on the ears.51 The chondritis may be severe enough to destroy the cartilage completely. If it is not recognized and treated early, cosmetic results may be unacceptable; these may include hyperpigmentation, hypertrophic scarring, mild deformity, moderate deformity, and total loss of the ear. There have been several procedures suggested for reconstruction with this condition.51,52

Seborrheic dermatitis Seborrheic dermatitis—a common skin disorder that typically presents as erythematous plaques or patches—can vary from mild dandruff to dense, diffuse, adherent scale that affects areas of the head and trunk where sebaceous glands are prominent, including the scalp, the nasolabial folds, the chest, the eyebrows, and the ears. This is a chronic inflammatory disorder with a precise etiology that remains unknown, although it is associated with genetic, environmental, and general health factors as well as with lipophilic Malassezia yeasts.53,54 With seborrheic dermatitis, plaques typically appear as red, flaky, greasy-looking patches of skin; the amount of flaking and erythema varies from patient to patient. Seborrheic dermatitis typically presents as a condition of

149 the scalp, which is a unique environment in humans: it is warm and dark, and it is particularly hospitable to infections and infestations introduced by fingers, hats, combs, and styling implements. 55 Distribution is symmetric. The condition commonly presents in hairy areas of the head (ie, the scalp, scalp margin, eyebrows, eyelashes, beard, and mustache); on the forehead; in the external ear canals; in the nasolabial folds; and in the body folds, including the axillae, the navel, the groin, and the inframammary and anogenital areas.56 Lesions typically worsen during the winter, whereas sun exposure during the warmer months appears to improve the clinical appearance of the disease. Scratching and emotional stress tend to aggravate the condition.56 The mildest form of seborrheic dermatitis occurs in 15% to 20% of the population, although it is important to differentiate between seborrheic dermatitis of the scalp and any scalp flaking, regardless of etiology.53 In general, the prevalence of seborrheic dermatitis ranges from 1% to 3% in the immunocompetent population and greatly increases in the immunocompromised population, particularly among patients with AIDS.54 Seborrheic dermatitis is more common among men than women, probably because androgens stimulate sebum production. In general, the condition initially appears during the teenage years or the 20s, with a waxing and waning course occurring throughout adulthood.53 The etiology of seborrheic dermatitis appears to depend on three factors: sebaceous gland secretions, microfloral metabolism, and individual susceptibility.57 Lipid-dependent Malassezia yeasts are causal factors in the development of seborrheic dermatitis; these are most commonly Malassezia globosa, with its high lipase activity, and Malassezia restricta. These two organisms predominate on the scalp of individuals with seborrheic dermatitis or dandruff.54,57 The primary goal of therapy for seborrheic dermatitis is symptom control, because, at this time, there is no cure for the disease. Various treatments are used for seborrheic dermatitis, including mild corticosteroids, antifungal agents, immunomodulators, and medicated shampoos.58 Although mild corticosteroids used alone can be effective for the management of symptoms, the disease is likely to recur quickly when steroid therapy is stopped. Antifungal agents should therefore be considered primary therapy.59 Because seborrheic dermatitis is a chronic recurring skin disorder, the goal of treatment is the development of a safe and effective regimen that is associated with low rates of recurrence. Treatment should incorporate an antifungal agent that is effective and tolerable to the patient both to reduce relapse and to promote patient adherence.58

Contact dermatitis Contact dermatitis, whether irritant or allergic, can involve the pinna as well as the external auditory canal. Allergic forms usually present acutely with erythematous, pruritic, edematous, and exudative lesions, whereas contact

150 dermatitis often has a more insidious onset with lichenification. Dose dependence is typical with irritant contact dermatitis. Allergic contact dermatitis is less dose dependent than irritant contact dermatitis, but the external auditory canal may react to allergens that do not cause a reaction elsewhere. Allergic contact dermatitis in the ear canal can result from almost any local irritant, including topical antiinfective agents and anesthetics as well as other topical preparations. Neomycin is one of the most common topical medications that causes allergic contact dermatitis. Irritant contact dermatitis may be associated with the use of hearing aids and rubber earplugs, so hypoallergenic silicone hearing aids are now available; both types, however, can be complicated by secondary bacterial infections.60 The most important treatment of contact dermatitis is the identification and removal of the irritant or allergen. Topical steroids are beneficial and may include a cream for the pinna when it is involved. An acidifying agent (usually Burrow's otic solution with 2% acetic acid [eg, Domeboro Otic, Bayer Pharmaceutical Inc. Drug Company, USA]) is often added to prevent secondary infections, to reacidify the skin, to dry weeping lesions, and to remove crusts. Three to five days of use three or four times daily is usually sufficient for topical therapy. Systemic steroids and antihistamines may be needed for severe allergic reactions.60

Atopic dermatitis Atopic dermatitis is a chronic and intensely pruritic reaction to allergens or stress that is also known as eczema. Poorly circumscribed erythema and small papules that are often obscured by excoriation are associated with the pruritus. Excoriation may result in a lichenified and hyperpigmented external auditory canal over time; this is typically part of more generalized skin involvement that includes the external ears, the face, and the neck. This condition is commonly associated with a personal or family history of atopy of the respiratory tract or eyes. The typical onset occurs during childhood.60 The treatment of atopic dermatitis is often difficult. A complete treatment plan emphasizes the need for a careful regimen of daily skin care and hygiene that includes the use of moisturizers and gentle soaps. Topical corticosteroids are key to the control of the disease but must be used with caution for sensitive sites such as the face and ears. Systemic antihistamines are useful to control pruritus.60,61

Acne The external auditory canal and the pinna contain sebaceous follicles that can develop comedones with occasional pustules and, less commonly, inflammatory acne lesions similar to those that may be found on the face and the upper trunk.60 The treatment of acne must be individualized. Topical therapy suffices for mild cases. Open comedones of the concha

S. Öztürkcan, S. Öztürkcan and the meatus can be manually removed by a physician with the use of a comedo extractor. Benzoyl peroxide is available in 5% to 10% washable lotion formulation that is suitable for use on the ears, where it may be applied during showering and rinsed off after several minutes.60

Lupus erythematosus Lupus erythematosus is a multisystem autoimmune disease that often has prominent cutaneous manifestations. Ear canal involvement is commonly associated with the discoid form of the disease. Epidermal atrophy causes the skin to have a shiny surface and telangiectasia, usually in association with erythema, scaling, and hypopigmentation. The cutaneous manifestations are among the most common initial presentations of juvenile systemic lupus erythematosus. The typical lesion is a malar facial rash, but a patient may sometimes present with a nonclassic lesions.60,62 The therapeutic plan should focus on reducing morbidity and mortality rates. The overall treatment of juvenile patients is similar to that of adult patients and depends on the clinical manifestations and the major organs involved. There are two parts to modern therapeutic strategies. The first part is induction therapy to control disease activity; potential organor life-threatening disease must be managed aggressively. After remission, the second part of treatment is maintenance therapy to avoid relapse and to control disease; most patients need to be treated for several years. Immunosuppressants are the drugs of choice for both parts of treatment, although efficacy and side effects must be balanced.62,63

Psoriasis Psoriasis is a common papulosquamous skin condition that affects approximately 2% of the general population. It is not hereditary in the Mendelian sense, but there does seem to be a genetic predisposition, with increased incidence found among family members of affected individuals. Psoriasis can be widespread or localized, and it has a chronic waxing and waning course. Well-documented triggers for exacerbation include trauma, infection, stress, and medications such as beta-blockers, lithium, and angiotensin-converting enzyme inhibitors. Patients often note that their psoriasis is better during the summer, when their skin is exposed to more sunlight.23,60,64,65 In the external ear, the involvement of the conchal bowl is commonly seen. Classic psoriatic lesions are described as well-demarcated, erythematous plaques with a “silvery scale." If the superficial scale is removed, pinpoint hemorrhage can be seen (ie, Auspitz’s sign), which can be helpful for making the diagnosis in some cases. Ear psoriasis may not demonstrate all of the classic findings and instead may involve nonspecific red, dry, and scaly skin. Patients will complain primarily of itching. Although it is possible to have psoriasis only in the ears, one will often find involvement of other areas of the body as well.23,64,65

Dermatologic diseases of the external ear Treatments for psoriasis include topical steroid solutions in moderation or on an intermittent basis. Bland emollients (eg, petroleum jelly, Aquaphor) can be applied with the fingertip. Other options include moisturizers with up to 10% urea to improve hydration and to remove scaling as well we topical vitamin D3 derivatives (eg, calcipotriene ointment).64,65

Acknowledgment Onur Gündoğan, MD, assisted with the preparation of this manuscript.

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