- Email: [email protected]
Dermoid tumor of the middle ear: A case report and review of the literature
Otolaryngology Case Reports 4 (2017) 18e20
Contents lists available at ScienceDirect
Otolaryngology Case Reports journal homepage: www.otolaryngologycasereports.com
Dermoid tumor of the middle ear: A case report and review of the literature Benjamin R. Campbell, Robert J. Yawn, Brendan P. O'Connell, Alejandro Rivas* Department of Otolaryngology e Vanderbilt University Medical Center, Nashville, TN, United States
a r t i c l e i n f o
a b s t r a c t
Article history: Received 6 July 2017 Accepted 19 August 2017 Available online 29 August 2017
Dermoid tumors are benign inclusion cysts that are uncommon in the pediatric population. Dermoid tumors of the middle ear are exceedingly rare. A 17-month old female presented with 4-month history of recurrent left otitis media with chronic drainage, speech delay, and worsening episodes of stumbling while walking. A temporal bone CT scan showed complete left middle ear and mastoid air cell opacification. The patient underwent left tympanomastoidectomy for removal of the middle ear mass with pathologic confirmation of a dermoid tumor. The patient continues to do well post-operatively without evidence of disease recurrence. To our knowledge, only thirteen cases of middle ear dermoid tumors have been reported. The clinical and radiographic presentation of dermoid tumors can be similar to congenital cholesteatoma, but they are histopathologically distinct lesions. Surgical removal of the dermoid tumor is an effective treatment strategy as recurrence rates are low. © 2017 Published by Elsevier Inc. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
Keywords: Dermoid tumor Middle ear Mastoid Inclusion cyst
1. Introduction Dermoid tumors are inclusion cysts lined with squamous epithelium that contain adnexal skin structures such as hair, smooth muscle, sebaceous and sweat glands, and fibroadipose tissue [1,2]. These are histologically distinct from epidermoid tumors, which are derived from the ectoderm germ layer, and only contain squamous epithelium but lack adnexal structures [1]. While the exact pathogenesis is unknown, dermoids are thought to arise from aberrant embryologic development in the third to fifth weeks of gestation when surface ectoderm fails to separate from the neural tube [1]. Within the middle ear and mastoid, dermoids are generally believed to form at points of fusion between the first pharyngeal cleft and pouch [3]. Dermoids are benign lesions and slowly expand over time secondary to intraluminal accumulation of keratin debris and sebaceous secretions [1]. They are generally associated with mild symptoms but can become more problematic as they increase in size and either impinge on or obstruct surrounding structures [1]. The average age of diagnosis for all pediatric dermoid tumors is
* Corresponding author. Department of Otolaryngology-Head and Neck Surgery, The Bill Wilkerson Center for Otolaryngology & Communication Sciences, 7209 Medical Center East, South Tower 1215 21st Avenue South, Nashville, TN, 372328605, United States. E-mail address: [email protected] (A. Rivas).
between 2 and 3 years of age [2,4]. While some studies have shown a slight female predominance, others have failed to show a difference in prevalence between genders [2,4e6]. The incidence of dermoid tumors is roughly 3 per 10,000 pediatric patients, with greater than 80% of pediatric dermoids occurring in the head and neck [4,5]. Within head and neck, dermoid tumors are most commonly found along embryologic fusion lines, with the most common locations being the periorbital area (40e65%), midline neck (20%), or nasolabial fold (3e6%) [2,4e6]. The reported incidence of dermoids of the temporal bone is highly variable, ranging from less than 1 to 10% of congenital dermoids [2,4,5]. Dermoid tumors of the middle ear are exceedingly rare, with less than fifteen cases ever reported. Here, we present a case of a dermoid tumor of the middle ear in a 17-month-old female with chronic otorrhea.
2. Case presentation A 17-month-old female presented to a tertiary otologic center with a 4-month purported history of recurrent left otitis media in the setting of chronic left ear drainage. Her past medical history was significant for a failed newborn hearing screen on the left ear and speech delay. Foul-smelling left ear drainage began at 13 months of age and was refractory to multiple courses of oral antibiotics and ciprofloxacin-dexamethasone 0.3%e0.1% otic drops. At
http://dx.doi.org/10.1016/j.xocr.2017.08.003 2468-5488/© 2017 Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
B.R. Campbell et al. / Otolaryngology Case Reports 4 (2017) 18e20
14 months of age, the patient began to have worsening episodes of dizziness and stumbling while walking. On examination, the patient's left ear was occluded with mucopurulent debris. Attempted microscopic examination of the tympanic membrane was unsuccessful because of squamous debris occluding the external auditory canal in clinic. A temporal bone CT scan was obtained (Fig. 1), which showed complete left middle ear and mastoid air cell opacification, with diffuse erosion of the ossicles and mastoid septae and severe thinning of the superior semicircular canal. The patient was scheduled for surgical extirpation of the lesion via a left tympanomastoidectomy. During the operation, a large fibrotic mass with components of squamous epithelium and hair follicles was found following the opening of the mastoid. The mass occupied the entire middle ear cavity and extended into the Eustachian tube. Frozen sections of the mass showed squamous epithelium and adnexal structures including hair follicles, sebaceous glands, and a small salivary gland, consistent with dermoid tumor (Fig. 2). To facilitate complete removal of the tumor, a large posterior atticotomy and canalplasty were performed. The dermoid was carefully dissected from the tegmen and mastoid and resected from the tympanic membrane, epitympanum, and hypotympanum. The incus was found to be eroded and was removed. Both the malleus and stapes were intact and preserved during the resection. The tympanic membrane was reconstructed with cartilage and fascia grafts, and ossicular chain reconstruction was deferred due to the extent of the disease. The patient tolerated the procedure well and was discharged on post-operative day one. Following discharge, the patient did well. At the time of last follow-up, the neotympanum was intact and the middle ear appeared clear without evidence of disease recurrence. The patient has since been referred to speech therapy and is scheduled to return to clinic for an audiogram and discussion of future ossicular chain reconstruction. 3. Discussion To the authors' knowledge, there are thirteen known cases of middle ear dermoid tumors, which are summarized in Table 1 [7e17]. The first reports of dermoid tumors of the middle ear and mastoid were published in 1866 in Transactions of the Pathological Society of London by Toynbee and Hinton [7,8]. From 1866 to 1938, there were six more cases of dermoids of the mastoid and middle ear reported in the literature [9e13]. Wagenhauser (1888) described a male patient who presented with frequent mastoid abscesses that eventually progressed to a postauricular cutaneous
19
Fig. 2. 200x magnification hemotoxylin and eosin stain of middle ear dermoid tumor. Arrow marks hair follicle and arrowhead marks sebaceous glands.
mastoid fistula and patient death [10]. Scheibe (1894) discussed two cases of men aged 41 and 24 that had middle ear dermoids present with recurrent otorrhea [11]. The first known female patient with a middle ear dermoid was described by Grunwald (1910) [12]. In 1962, Howie published a case of a 29-year-old woman who presented with vertigo and vomiting as well as severe left-sided hearing loss. On examination of her tympanic membrane, a small mass was found to occupy the hypotympanum. Multi-stage surgical removal was required. Interestingly in this case, the dermoid had eroded the hypotympanum allowing the jugular bulb to herniate into the middle ear [14]. The oldest patient to present with a dermoid tumor of the middle ear was a 67-year-old male described by Steel in 1976. Following years of intermittent secretory otitis media, this patient underwent surgical exploration of the mastoid with successful dermoid removal with minimal post-operative deficits [15]. Minatogawa (1993) has been the latest to report a dermoid tumor of the middle ear. This case is unique because the patient presented with unilateral conductive hearing loss in the absence of any prior history of otitis media or otorrhea [17]. Over 20 reports of dermoids originating from the eustachian tube have been published, with some progressing to involve the middle ear, mastoid, and nasopharynx [18,19]. The most noteworthy case of a eustachian tube dermoid was published in 2005 [2]. In this case, the patient was initially treated with
Fig. 1. Axial (A) and coronal (B) non-contrasted computed tomography scan of the left ear demonstrating diffuse opacification of the mastoid and middle ear with bony erosion of the mastoid air cell system.
20
B.R. Campbell et al. / Otolaryngology Case Reports 4 (2017) 18e20
Table 1 Dermoid tumors of the mastoid and middle ear. Authors
Age
Sex
Presenting Symptoms
Treatment
Toynbee (1866) Hinton (1866) Schwartze (1885) Wagenhauser (1888) Scheibe (1894)
NA 12 years NA NA 41 years 24 years
NA male NA male Male male
dermoid of mastoid found on autopsy dermoid of middle ear dermoid of middle ear mastoid abscesses and postauricular cutaneous mastoid fistula recurrent otorrhea & polyp recurrent otorrhea
NA NA NA NA polypectomy and conservative polypectomy with snare
Grunwald (1910) Watanabe (1938) Howie (1962) Steel (1976) Fried (1984) Vrabec (1992) Minatogawa (1993)
27 years NA 29 years 67 years 22 month 14 month 6 years
female NA female male male female female
recurrent otitis media & polyp otorrhea and tympanic membrane perforation vertigo, vomiting, & hearing loss recurrent otorrhea, otitis externa & hearing loss recurrent secretory otitis media & hearing loss recurrent otitis media hearing loss
conservative, later surgery NA mastoidectomy surgery and resection tympanomastoidectomy tympanotomy and excision middle ear surgery and resection
NA ¼ Not available.
nasopharyngeal excision of the dermoid, but 13 months later, there was recurrence of the dermoid tumor within the middle ear and mastoid process. To our knowledge, this is the only documented case of dermoid tumor recurrence. The patient was subsequently treated with re-excision through a tympanomastoid-infratemporal approach [2]. Over the past 30 years, the age at diagnosis of dermoid tumors of the middle ear and mastoid has decreased from adulthood to early childhood. Now, surgical treatment of dermoid tumors normally occurs within the first few years of life, likely due to the use of better imaging studies and subsequent earlier surgical intervention. Our patient is the second youngest reported case of a dermoid tumor of the middle ear. Of the reported cases of middle ear dermoid tumors, 45% have been female indicating no clear sex predominance. Our patient's presenting symptoms of chronic otorrhea and hearing difficulties are consistent with the presenting symptoms of other middle ear dermoids in the literature. However, our patient is unique in that she also presented with the vestibular symptoms of dizziness and unsteadiness with walking. Vestibular symptoms have only been reported in one other middle ear dermoid tumor patient [14]. 4. Conclusions Dermoid tumors involving the middle ear and mastoid are rare. Their presentation can be similar clinically and radiographically to congenital cholesteatoma, but they are distinct histopathologically by the presence of adnexal structures. Surgical removal of the tumor is an effective treatment strategy as recurrence rates are low. Conflict of interest The authors declare no conflict of interest in the preparation of this manuscript.
Financial disclosure The authors declare no specific financial interests, relationship, or affiliations to the subject of the manuscript.
References [1] Smirniotopoulos JG, Chiechi MV. Teratomas, dermoids, and epidermoids of the head and neck. Radiographics 1995;15:1437e55. [2] Pryor SG, Lewis JE, Weaver AL, Orvidas LJ. Pediatric dermoid cysts of the head and neck. Otolaryngol Head Neck Surg 2005;132:938e42. [3] Fried MP, Vernick DM. Dermoid cyst of the middle ear and mastoid. Otolaryngol Head Neck Surg 1984;92:594e6. [4] Orozco-Covarrubias L, Lara-Carpio R, Saez-De-Ocariz M, et al. Dermoid cysts: a report of 75 pediatric patients. Pediatr Dermatol 2013;30(6):706e11. [5] Pollard ZF, Harley RD, Calhoun J. Dermoid cysts in children. Pediatrics 1976;57:379e82. [6] Brownstein MH, Helwig EB. Subcutaneous dermoid cysts. Arch Dermatol 1973;107:237e9. [7] Toynbee J. Trans Path Soc Lond 1866;17:274. [8] Hinton J. Trans Path Soc Lond 1866;17:275. [9] Schwartze H. Lehrb Chirrug Krankh Ohres 1885:328. [10] Wagenhauser I. Arch fur Ohrenheilkd 1888;26(4). [11] Scheibe A. Zwei Falle von behaarter Granulations geschwulst im Mittelohr. Z fur Ohrenheilkd 1894;25:108e12. [12] Grunwald L. Beitrage zur Kenntnis kongenitaler Geschwiilste und Missbildungen an Ohr und Nase: 1. Ein Fall von Dermoid der Mittelohrraume und seine Bedeutung fiir die Cholesteatomfrage. Z fiir Ohrenheilkd fiir Krankh Luftweg 1910;60:270e9. [13] Watanabe T. Otol Tokyo 1938;11:506. [14] Howie TO. A case of dermoid or developmental cyst of the middle-ear cavity. J Laryngol Otol 1962;76:62e6. [15] Steel A. Secretory otitis media due to a hair-bearing dermoid of the mastoid cavity. J Layngol Otol 1976;90:979e89. [16] Vrabec JT, Scwaber MK. Dermoid tumor of the middle ear: case report and literature review 1992;vol. 13(6):580e1. [17] Minatogawa T, Node MN, Fukuda I, Kumoi T. Dermoid cyst in the middle ear. J Laryngol Otol 1993;107:335e8. [18] Lepera D, Volpi L, De Bernardi F, et al. Endoscopic transnasal resection of eustachian-tube dermoid in a new-born infant. Auris Nasus Larynx 2015;42: 235e40. [19] Kollias SS, Ball Jr WS, Prenger EC, Myers 3rd CM. Dermoids of the eustachian tube: CT and MR findings with histologica correlation. AJNR Am J Neuroradiol 1995;16:663e8.
Contents lists available at ScienceDirect
Otolaryngology Case Reports journal homepage: www.otolaryngologycasereports.com
Dermoid tumor of the middle ear: A case report and review of the literature Benjamin R. Campbell, Robert J. Yawn, Brendan P. O'Connell, Alejandro Rivas* Department of Otolaryngology e Vanderbilt University Medical Center, Nashville, TN, United States
a r t i c l e i n f o
a b s t r a c t
Article history: Received 6 July 2017 Accepted 19 August 2017 Available online 29 August 2017
Dermoid tumors are benign inclusion cysts that are uncommon in the pediatric population. Dermoid tumors of the middle ear are exceedingly rare. A 17-month old female presented with 4-month history of recurrent left otitis media with chronic drainage, speech delay, and worsening episodes of stumbling while walking. A temporal bone CT scan showed complete left middle ear and mastoid air cell opacification. The patient underwent left tympanomastoidectomy for removal of the middle ear mass with pathologic confirmation of a dermoid tumor. The patient continues to do well post-operatively without evidence of disease recurrence. To our knowledge, only thirteen cases of middle ear dermoid tumors have been reported. The clinical and radiographic presentation of dermoid tumors can be similar to congenital cholesteatoma, but they are histopathologically distinct lesions. Surgical removal of the dermoid tumor is an effective treatment strategy as recurrence rates are low. © 2017 Published by Elsevier Inc. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
Keywords: Dermoid tumor Middle ear Mastoid Inclusion cyst
1. Introduction Dermoid tumors are inclusion cysts lined with squamous epithelium that contain adnexal skin structures such as hair, smooth muscle, sebaceous and sweat glands, and fibroadipose tissue [1,2]. These are histologically distinct from epidermoid tumors, which are derived from the ectoderm germ layer, and only contain squamous epithelium but lack adnexal structures [1]. While the exact pathogenesis is unknown, dermoids are thought to arise from aberrant embryologic development in the third to fifth weeks of gestation when surface ectoderm fails to separate from the neural tube [1]. Within the middle ear and mastoid, dermoids are generally believed to form at points of fusion between the first pharyngeal cleft and pouch [3]. Dermoids are benign lesions and slowly expand over time secondary to intraluminal accumulation of keratin debris and sebaceous secretions [1]. They are generally associated with mild symptoms but can become more problematic as they increase in size and either impinge on or obstruct surrounding structures [1]. The average age of diagnosis for all pediatric dermoid tumors is
* Corresponding author. Department of Otolaryngology-Head and Neck Surgery, The Bill Wilkerson Center for Otolaryngology & Communication Sciences, 7209 Medical Center East, South Tower 1215 21st Avenue South, Nashville, TN, 372328605, United States. E-mail address: [email protected] (A. Rivas).
between 2 and 3 years of age [2,4]. While some studies have shown a slight female predominance, others have failed to show a difference in prevalence between genders [2,4e6]. The incidence of dermoid tumors is roughly 3 per 10,000 pediatric patients, with greater than 80% of pediatric dermoids occurring in the head and neck [4,5]. Within head and neck, dermoid tumors are most commonly found along embryologic fusion lines, with the most common locations being the periorbital area (40e65%), midline neck (20%), or nasolabial fold (3e6%) [2,4e6]. The reported incidence of dermoids of the temporal bone is highly variable, ranging from less than 1 to 10% of congenital dermoids [2,4,5]. Dermoid tumors of the middle ear are exceedingly rare, with less than fifteen cases ever reported. Here, we present a case of a dermoid tumor of the middle ear in a 17-month-old female with chronic otorrhea.
2. Case presentation A 17-month-old female presented to a tertiary otologic center with a 4-month purported history of recurrent left otitis media in the setting of chronic left ear drainage. Her past medical history was significant for a failed newborn hearing screen on the left ear and speech delay. Foul-smelling left ear drainage began at 13 months of age and was refractory to multiple courses of oral antibiotics and ciprofloxacin-dexamethasone 0.3%e0.1% otic drops. At
http://dx.doi.org/10.1016/j.xocr.2017.08.003 2468-5488/© 2017 Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
B.R. Campbell et al. / Otolaryngology Case Reports 4 (2017) 18e20
14 months of age, the patient began to have worsening episodes of dizziness and stumbling while walking. On examination, the patient's left ear was occluded with mucopurulent debris. Attempted microscopic examination of the tympanic membrane was unsuccessful because of squamous debris occluding the external auditory canal in clinic. A temporal bone CT scan was obtained (Fig. 1), which showed complete left middle ear and mastoid air cell opacification, with diffuse erosion of the ossicles and mastoid septae and severe thinning of the superior semicircular canal. The patient was scheduled for surgical extirpation of the lesion via a left tympanomastoidectomy. During the operation, a large fibrotic mass with components of squamous epithelium and hair follicles was found following the opening of the mastoid. The mass occupied the entire middle ear cavity and extended into the Eustachian tube. Frozen sections of the mass showed squamous epithelium and adnexal structures including hair follicles, sebaceous glands, and a small salivary gland, consistent with dermoid tumor (Fig. 2). To facilitate complete removal of the tumor, a large posterior atticotomy and canalplasty were performed. The dermoid was carefully dissected from the tegmen and mastoid and resected from the tympanic membrane, epitympanum, and hypotympanum. The incus was found to be eroded and was removed. Both the malleus and stapes were intact and preserved during the resection. The tympanic membrane was reconstructed with cartilage and fascia grafts, and ossicular chain reconstruction was deferred due to the extent of the disease. The patient tolerated the procedure well and was discharged on post-operative day one. Following discharge, the patient did well. At the time of last follow-up, the neotympanum was intact and the middle ear appeared clear without evidence of disease recurrence. The patient has since been referred to speech therapy and is scheduled to return to clinic for an audiogram and discussion of future ossicular chain reconstruction. 3. Discussion To the authors' knowledge, there are thirteen known cases of middle ear dermoid tumors, which are summarized in Table 1 [7e17]. The first reports of dermoid tumors of the middle ear and mastoid were published in 1866 in Transactions of the Pathological Society of London by Toynbee and Hinton [7,8]. From 1866 to 1938, there were six more cases of dermoids of the mastoid and middle ear reported in the literature [9e13]. Wagenhauser (1888) described a male patient who presented with frequent mastoid abscesses that eventually progressed to a postauricular cutaneous
19
Fig. 2. 200x magnification hemotoxylin and eosin stain of middle ear dermoid tumor. Arrow marks hair follicle and arrowhead marks sebaceous glands.
mastoid fistula and patient death [10]. Scheibe (1894) discussed two cases of men aged 41 and 24 that had middle ear dermoids present with recurrent otorrhea [11]. The first known female patient with a middle ear dermoid was described by Grunwald (1910) [12]. In 1962, Howie published a case of a 29-year-old woman who presented with vertigo and vomiting as well as severe left-sided hearing loss. On examination of her tympanic membrane, a small mass was found to occupy the hypotympanum. Multi-stage surgical removal was required. Interestingly in this case, the dermoid had eroded the hypotympanum allowing the jugular bulb to herniate into the middle ear [14]. The oldest patient to present with a dermoid tumor of the middle ear was a 67-year-old male described by Steel in 1976. Following years of intermittent secretory otitis media, this patient underwent surgical exploration of the mastoid with successful dermoid removal with minimal post-operative deficits [15]. Minatogawa (1993) has been the latest to report a dermoid tumor of the middle ear. This case is unique because the patient presented with unilateral conductive hearing loss in the absence of any prior history of otitis media or otorrhea [17]. Over 20 reports of dermoids originating from the eustachian tube have been published, with some progressing to involve the middle ear, mastoid, and nasopharynx [18,19]. The most noteworthy case of a eustachian tube dermoid was published in 2005 [2]. In this case, the patient was initially treated with
Fig. 1. Axial (A) and coronal (B) non-contrasted computed tomography scan of the left ear demonstrating diffuse opacification of the mastoid and middle ear with bony erosion of the mastoid air cell system.
20
B.R. Campbell et al. / Otolaryngology Case Reports 4 (2017) 18e20
Table 1 Dermoid tumors of the mastoid and middle ear. Authors
Age
Sex
Presenting Symptoms
Treatment
Toynbee (1866) Hinton (1866) Schwartze (1885) Wagenhauser (1888) Scheibe (1894)
NA 12 years NA NA 41 years 24 years
NA male NA male Male male
dermoid of mastoid found on autopsy dermoid of middle ear dermoid of middle ear mastoid abscesses and postauricular cutaneous mastoid fistula recurrent otorrhea & polyp recurrent otorrhea
NA NA NA NA polypectomy and conservative polypectomy with snare
Grunwald (1910) Watanabe (1938) Howie (1962) Steel (1976) Fried (1984) Vrabec (1992) Minatogawa (1993)
27 years NA 29 years 67 years 22 month 14 month 6 years
female NA female male male female female
recurrent otitis media & polyp otorrhea and tympanic membrane perforation vertigo, vomiting, & hearing loss recurrent otorrhea, otitis externa & hearing loss recurrent secretory otitis media & hearing loss recurrent otitis media hearing loss
conservative, later surgery NA mastoidectomy surgery and resection tympanomastoidectomy tympanotomy and excision middle ear surgery and resection
NA ¼ Not available.
nasopharyngeal excision of the dermoid, but 13 months later, there was recurrence of the dermoid tumor within the middle ear and mastoid process. To our knowledge, this is the only documented case of dermoid tumor recurrence. The patient was subsequently treated with re-excision through a tympanomastoid-infratemporal approach [2]. Over the past 30 years, the age at diagnosis of dermoid tumors of the middle ear and mastoid has decreased from adulthood to early childhood. Now, surgical treatment of dermoid tumors normally occurs within the first few years of life, likely due to the use of better imaging studies and subsequent earlier surgical intervention. Our patient is the second youngest reported case of a dermoid tumor of the middle ear. Of the reported cases of middle ear dermoid tumors, 45% have been female indicating no clear sex predominance. Our patient's presenting symptoms of chronic otorrhea and hearing difficulties are consistent with the presenting symptoms of other middle ear dermoids in the literature. However, our patient is unique in that she also presented with the vestibular symptoms of dizziness and unsteadiness with walking. Vestibular symptoms have only been reported in one other middle ear dermoid tumor patient [14]. 4. Conclusions Dermoid tumors involving the middle ear and mastoid are rare. Their presentation can be similar clinically and radiographically to congenital cholesteatoma, but they are distinct histopathologically by the presence of adnexal structures. Surgical removal of the tumor is an effective treatment strategy as recurrence rates are low. Conflict of interest The authors declare no conflict of interest in the preparation of this manuscript.
Financial disclosure The authors declare no specific financial interests, relationship, or affiliations to the subject of the manuscript.
References [1] Smirniotopoulos JG, Chiechi MV. Teratomas, dermoids, and epidermoids of the head and neck. Radiographics 1995;15:1437e55. [2] Pryor SG, Lewis JE, Weaver AL, Orvidas LJ. Pediatric dermoid cysts of the head and neck. Otolaryngol Head Neck Surg 2005;132:938e42. [3] Fried MP, Vernick DM. Dermoid cyst of the middle ear and mastoid. Otolaryngol Head Neck Surg 1984;92:594e6. [4] Orozco-Covarrubias L, Lara-Carpio R, Saez-De-Ocariz M, et al. Dermoid cysts: a report of 75 pediatric patients. Pediatr Dermatol 2013;30(6):706e11. [5] Pollard ZF, Harley RD, Calhoun J. Dermoid cysts in children. Pediatrics 1976;57:379e82. [6] Brownstein MH, Helwig EB. Subcutaneous dermoid cysts. Arch Dermatol 1973;107:237e9. [7] Toynbee J. Trans Path Soc Lond 1866;17:274. [8] Hinton J. Trans Path Soc Lond 1866;17:275. [9] Schwartze H. Lehrb Chirrug Krankh Ohres 1885:328. [10] Wagenhauser I. Arch fur Ohrenheilkd 1888;26(4). [11] Scheibe A. Zwei Falle von behaarter Granulations geschwulst im Mittelohr. Z fur Ohrenheilkd 1894;25:108e12. [12] Grunwald L. Beitrage zur Kenntnis kongenitaler Geschwiilste und Missbildungen an Ohr und Nase: 1. Ein Fall von Dermoid der Mittelohrraume und seine Bedeutung fiir die Cholesteatomfrage. Z fiir Ohrenheilkd fiir Krankh Luftweg 1910;60:270e9. [13] Watanabe T. Otol Tokyo 1938;11:506. [14] Howie TO. A case of dermoid or developmental cyst of the middle-ear cavity. J Laryngol Otol 1962;76:62e6. [15] Steel A. Secretory otitis media due to a hair-bearing dermoid of the mastoid cavity. J Layngol Otol 1976;90:979e89. [16] Vrabec JT, Scwaber MK. Dermoid tumor of the middle ear: case report and literature review 1992;vol. 13(6):580e1. [17] Minatogawa T, Node MN, Fukuda I, Kumoi T. Dermoid cyst in the middle ear. J Laryngol Otol 1993;107:335e8. [18] Lepera D, Volpi L, De Bernardi F, et al. Endoscopic transnasal resection of eustachian-tube dermoid in a new-born infant. Auris Nasus Larynx 2015;42: 235e40. [19] Kollias SS, Ball Jr WS, Prenger EC, Myers 3rd CM. Dermoids of the eustachian tube: CT and MR findings with histologica correlation. AJNR Am J Neuroradiol 1995;16:663e8.