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A suprapubic dermoid cyst confused with cutaneous endometriosis: a case report
CASE REPORT A suprapubic dermoid cyst confused with cutaneous endometriosis: a case report Mi-Kyung Kim, M.D.,a Jung Ryeol Lee, M.D.,a Byung Chul Jee, M.D., Ph.D.,a Seung-Yup Ku, M.D., Ph.D.,a,b Chang Suk Suh, M.D., Ph.D.,a,b and Seok Hyun Kim, M.D., Ph.D.a,b a
Department of Obstetrics and Gynecology, College of Medicine, and b Institute of Reproductive Medicine and Population, Medical Research Center, Seoul National University, Seoul, Korea
Objective: To describe a case of suprapubic dermoid cyst that had been mistaken for cutaneous endometriosis. Design: Case report. Setting: Department of Obstetrics and Gynecology, Seoul National University Hospital, Korea. Patient(s): A 22-year-old woman with a 5-year history of a slowly growing suprapubic mass, which had begun to bleed intermittently 6 months before presentation. Intervention(s): Complete excision of the suprapubic mass and primary closure of the wound. Main Outcome Measure(s): The natural course of the suprapubic dermoid cyst and histologic findings. Result(s): The excised suprapubic mass was histologically diagnosed as a dermoid cyst. Conclusion(s): Subcutaneous dermoid cysts should be part of the differential diagnosis of suprapubic wall masses. (Fertil Steril 2008;89:724.e5–7. 2008 by American Society for Reproductive Medicine.) Key Words: Dermoid cyst, suprapubic, subcutaneous, endometriosis
Dermoid cysts are subcutaneous cysts that result from the sequestration of cutaneous tissues along embryonal lines of closure. They are composed of epidermis and skin appendages, and they lack structures foreign to skin, which differentiates them from dermoids in the ovarian, testicular, retroperitoneal, or sacrococcygeal region (1). They are usually present at birth, chiefly in the region of the head and neck. Dermoid cysts in other regions are rarely reported. The presence of a dermoid cyst in the suprapubic region has not been reported previously. Dermoid cysts are usually not considered in the differential diagnosis of suprapubic masses. The more common considerations for suprapubic masses include endometrioma, incisional hernia, abscess, hematoma, and lipoma. We report the case of a young woman with a suprapubic lesion that presented as a slowly growing mass with intermittent bloody discharge; the mass was initially thought to be cutaneous endometriosis, but the histologic findings confirmed a dermoid cyst. This is the first case report of a suprapubic dermoid cyst. CASE REPORT A 22-year-old woman presented with a 5-year history of a suprapubic nodule. The size of the mass fluctuated with Received March 10, 2007; revised and accepted March 27, 2007. Reprint requests: Seok Hyun Kim, M.D., Ph.D., Department of Obstetrics and Gynecology, College of Medicine, Seoul National University, 28 Yeongeon-dong, Jongno-gu, Seoul, 110-744, Korea (FAX: 822-762-3599; E-mail: [email protected]).
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the menstrual cycle. The overall size of the mass gradually enlarged. The mass was tender on palpation but did not cause cyclic pain. The patient visited the dermatology department complaining of an intermittent bloody discharge from the mass that had begun 6 months before the visit. Based on the clinical impression of an endometrioma, the patient was referred to our department for excision of the mass. The patient reported a regular menstrual cycle and did not complain of dysmenorrhea. She denied sexual activity. On examination, a 3-cm sized subcutaneous mass, covered with discolored skin and crust, was palpated (Fig. 1). The mass was tender and oozed blood. Laboratory testing including complete blood cell count and renal and liver function tests were all normal. The level of CA-125 was 14 IU/mL. Pelvic ultrasound revealed no specific abnormalities. The medical history was unremarkable. The mass was completely excised under spinal anesthesia, and the incision was closed with primary closure. After excision, the wound healed uneventfully except for the formation of a keloid scar.
Histopathology The subcutaneous mass measured 2.5 2.5 1.0 cm. Examination of the resected specimen showed a cyst filled with jelly-like material, which measured 0.7 0.5 0.5 cm. The lining epithelium of the cyst was mainly composed of squamous epithelial cells. In the cystic lumen, cross sections of hair shafts were present (Fig. 2). In the surrounding stroma,
Fertility and Sterility Vol. 89, No. 3, March 2008 Copyright ª2008 American Society for Reproductive Medicine, Published by Elsevier Inc.
0015-0282/08/$34.00 doi:10.1016/j.fertnstert.2007.03.082
FIGURE 1
FIGURE 2
Gross finding of suprapubic lesion just prior to operation showing inflamed lesion with crust.
Microscopic finding of dermoid cyst. The cyst is lined with squamous epithelium. Hair shafts are seen in the lumen.
Kim. Dermoid cyst in the suprapubic area. Fertil Steril 2008. Kim. Dermoid cyst in the suprapubic area. Fertil Steril 2008.
inflammatory cell infiltrates and some foci of foreign-body giant cell aggregates were noted, which implied previous rupture of the cyst. On serial section, sebaceous glands and vascular stroma could be identified. Combining these features, the diagnosis of a dermoid cyst was made.
DISCUSSION Dermoid cysts are congenital cutaneous inclusion cysts, which are thought to result from the sequestration of cutaneous tissue along the lines of embryonic fusion. Characteristically, subcutaneous dermoid cysts contain only epithelium and skin appendages. This feature differentiates dermoid cysts from ovarian dermoids histologically (1). Ovarian dermoids or teratomas usually contain tissues derived from all three germ layers other than skin, such as teeth, cartilage, thyroid tissue, or neural tissue. Subcutaneous dermoid cysts are found most often in the skin of the forehead, usually in the supraorbital region or in the midline. There have been only a few case reports of dermoid cysts occurring at sites other than the head and neck region such as the dorsum of penis or the inguinal canal (2, 3). However, a dermoid cyst at the suprapubic region has not been previously reported. Dermoid cysts usually present as firm, asymptomatic, solitary cystic masses. Although these cysts enlarge slowly, inflammation or infection may cause a sudden increase in size. However, these clinical findings are not unique to a dermoid cyst. Other lesions including endometrioma, lipoma, and other dermatologic lesions can exhibit similar findings. In this case, the initial clinical diagnosis was an endometrioma. Fertility and Sterility
Some factors may be helpful in the differential diagnosis. Abdominal wall endometriosis usually grows in surgical scars; in addition, an endometrioma frequently fluctuates in size, and the severity of pain is associated with the menstrual cycle (4). However, these factors are not conclusive. Nearly half of the patients with abdominal wall endometriosis may have noncyclic pain. There has been one case report that documented an abdominal wall mass with recurrent pain occurring in a woman without surgical history, which was eventually diagnosed as an endometrioma (5). Therefore, the final diagnosis can be made only after histologic examination of the mass. One explanation for the cyclic swelling and bleeding of the suprapubic mass in the case reported here may be intermittent inflammation secondary to trauma and resultant rupture of the cyst. The histopathologic differential diagnosis of a suprapubic mass includes epidermoid cyst, sebaceous cyst, cystic teratoma, and dermoid cyst (1). Epidermoid and sebaceous cysts may appear similar to dermoid cysts because they are lined by stratified squamous epithelium. However, they are usually intradermal in location rather than subcutaneous, and they do not contain skin appendages as essential components. Cystic teratomas are composed of tissues derived from more than one germinal plate; they are generally localized in the sacrococcygeal region. Their occasional association with other malformations differentiates them from dermoid cysts. Although the occurrence of a suprapubic dermoid cyst has not been reported to date, four cases of suprapubic pilonidal sinuses with similar clinical features have been reported (6–9). A pilonidal sinus is postulated to be an acquired lesion 724.e6
that results from friction, whereas a dermoid cyst is congenital in origin. Pilonidal sinuses occur most commonly in the sacrococcygeal area. Although it may be difficult to differentiate a pilonidal sinus from a dermoid cyst where the squamous epithelium is replaced by granulation tissue, a pilonidal sinus characteristically forms a sinus tract surrounded by chronic inflammation and fibrotic tissue and does not contain skin appendages. The cyst identified in the case presented here was lined with squamous epithelium and contained skin appendages including hair and sebaceous glands. There were no other nonskin structures identified. The features identified confirmed the diagnosis of a dermoid cyst. In addition, the inflammatory cell infiltrates around the cyst may explain the fluctuation of size resulting from intermittent rupture of the cyst. Treatment requires complete excision of the cyst with primary closure. Although the possibility exists, there have been no cases of malignant transformation of a dermoid cyst reported to date. Our experience with this case illustrates the
724.e7
Kim et al.
Dermoid cyst in the suprapubic area
importance of considering a dermoid cyst in the differential diagnosis of suprapubic wall masses.
REFERENCES 1. Brownstein MH, Helwig EB. Subcutaneous dermoid cysts. Arch Dermatol 1973;107:237–9. 2. Leeming R, Olsen M, Ponsky JL. Inguinal dermoid cyst presenting as an incarcerated inguinal hernia. J Pediatric Surg 1992;1:117–8. 3. Tomasini C, Aloi F, Puiatti P, Caliendo V. Dermoid cyst of the penis. Dermatology 1997;194:188–90. 4. Yoram W, Haddad R. Endometriosis in abdominal scars: a diagnostic pitfall. Am J Surg 1996;62:1042–4. 5. Tomas E, Martin A, Garfia C, Sanchez FG, Morillas JD, Castellano TG, et al. Abdominal wall endometriosis in absence of previous surgery. J Ultrasound Med 1999;18:373–4. 6. MacLeod RG. Pilonidal sinus of the suprapubic region. Br Med J 1953;1: 710–1. 7. Crosby DL. Pilonidal sinus of the suprapubic region. Br J Surg 1962;49: 467–8. 8. Patey DH, Curry RC. Pilonidal sinus presenting in the suprapubic region of a woman. Lancet 1962;1:620–1. 9. Logan G, Edwards SO. Pilonidal sinus of the suprapubic region. Aust NZ J Surg 1971;11:60–2.
Vol. 89, No. 3, March 2008
Department of Obstetrics and Gynecology, College of Medicine, and b Institute of Reproductive Medicine and Population, Medical Research Center, Seoul National University, Seoul, Korea
Objective: To describe a case of suprapubic dermoid cyst that had been mistaken for cutaneous endometriosis. Design: Case report. Setting: Department of Obstetrics and Gynecology, Seoul National University Hospital, Korea. Patient(s): A 22-year-old woman with a 5-year history of a slowly growing suprapubic mass, which had begun to bleed intermittently 6 months before presentation. Intervention(s): Complete excision of the suprapubic mass and primary closure of the wound. Main Outcome Measure(s): The natural course of the suprapubic dermoid cyst and histologic findings. Result(s): The excised suprapubic mass was histologically diagnosed as a dermoid cyst. Conclusion(s): Subcutaneous dermoid cysts should be part of the differential diagnosis of suprapubic wall masses. (Fertil Steril 2008;89:724.e5–7. 2008 by American Society for Reproductive Medicine.) Key Words: Dermoid cyst, suprapubic, subcutaneous, endometriosis
Dermoid cysts are subcutaneous cysts that result from the sequestration of cutaneous tissues along embryonal lines of closure. They are composed of epidermis and skin appendages, and they lack structures foreign to skin, which differentiates them from dermoids in the ovarian, testicular, retroperitoneal, or sacrococcygeal region (1). They are usually present at birth, chiefly in the region of the head and neck. Dermoid cysts in other regions are rarely reported. The presence of a dermoid cyst in the suprapubic region has not been reported previously. Dermoid cysts are usually not considered in the differential diagnosis of suprapubic masses. The more common considerations for suprapubic masses include endometrioma, incisional hernia, abscess, hematoma, and lipoma. We report the case of a young woman with a suprapubic lesion that presented as a slowly growing mass with intermittent bloody discharge; the mass was initially thought to be cutaneous endometriosis, but the histologic findings confirmed a dermoid cyst. This is the first case report of a suprapubic dermoid cyst. CASE REPORT A 22-year-old woman presented with a 5-year history of a suprapubic nodule. The size of the mass fluctuated with Received March 10, 2007; revised and accepted March 27, 2007. Reprint requests: Seok Hyun Kim, M.D., Ph.D., Department of Obstetrics and Gynecology, College of Medicine, Seoul National University, 28 Yeongeon-dong, Jongno-gu, Seoul, 110-744, Korea (FAX: 822-762-3599; E-mail: [email protected]).
724.e5
the menstrual cycle. The overall size of the mass gradually enlarged. The mass was tender on palpation but did not cause cyclic pain. The patient visited the dermatology department complaining of an intermittent bloody discharge from the mass that had begun 6 months before the visit. Based on the clinical impression of an endometrioma, the patient was referred to our department for excision of the mass. The patient reported a regular menstrual cycle and did not complain of dysmenorrhea. She denied sexual activity. On examination, a 3-cm sized subcutaneous mass, covered with discolored skin and crust, was palpated (Fig. 1). The mass was tender and oozed blood. Laboratory testing including complete blood cell count and renal and liver function tests were all normal. The level of CA-125 was 14 IU/mL. Pelvic ultrasound revealed no specific abnormalities. The medical history was unremarkable. The mass was completely excised under spinal anesthesia, and the incision was closed with primary closure. After excision, the wound healed uneventfully except for the formation of a keloid scar.
Histopathology The subcutaneous mass measured 2.5 2.5 1.0 cm. Examination of the resected specimen showed a cyst filled with jelly-like material, which measured 0.7 0.5 0.5 cm. The lining epithelium of the cyst was mainly composed of squamous epithelial cells. In the cystic lumen, cross sections of hair shafts were present (Fig. 2). In the surrounding stroma,
Fertility and Sterility Vol. 89, No. 3, March 2008 Copyright ª2008 American Society for Reproductive Medicine, Published by Elsevier Inc.
0015-0282/08/$34.00 doi:10.1016/j.fertnstert.2007.03.082
FIGURE 1
FIGURE 2
Gross finding of suprapubic lesion just prior to operation showing inflamed lesion with crust.
Microscopic finding of dermoid cyst. The cyst is lined with squamous epithelium. Hair shafts are seen in the lumen.
Kim. Dermoid cyst in the suprapubic area. Fertil Steril 2008. Kim. Dermoid cyst in the suprapubic area. Fertil Steril 2008.
inflammatory cell infiltrates and some foci of foreign-body giant cell aggregates were noted, which implied previous rupture of the cyst. On serial section, sebaceous glands and vascular stroma could be identified. Combining these features, the diagnosis of a dermoid cyst was made.
DISCUSSION Dermoid cysts are congenital cutaneous inclusion cysts, which are thought to result from the sequestration of cutaneous tissue along the lines of embryonic fusion. Characteristically, subcutaneous dermoid cysts contain only epithelium and skin appendages. This feature differentiates dermoid cysts from ovarian dermoids histologically (1). Ovarian dermoids or teratomas usually contain tissues derived from all three germ layers other than skin, such as teeth, cartilage, thyroid tissue, or neural tissue. Subcutaneous dermoid cysts are found most often in the skin of the forehead, usually in the supraorbital region or in the midline. There have been only a few case reports of dermoid cysts occurring at sites other than the head and neck region such as the dorsum of penis or the inguinal canal (2, 3). However, a dermoid cyst at the suprapubic region has not been previously reported. Dermoid cysts usually present as firm, asymptomatic, solitary cystic masses. Although these cysts enlarge slowly, inflammation or infection may cause a sudden increase in size. However, these clinical findings are not unique to a dermoid cyst. Other lesions including endometrioma, lipoma, and other dermatologic lesions can exhibit similar findings. In this case, the initial clinical diagnosis was an endometrioma. Fertility and Sterility
Some factors may be helpful in the differential diagnosis. Abdominal wall endometriosis usually grows in surgical scars; in addition, an endometrioma frequently fluctuates in size, and the severity of pain is associated with the menstrual cycle (4). However, these factors are not conclusive. Nearly half of the patients with abdominal wall endometriosis may have noncyclic pain. There has been one case report that documented an abdominal wall mass with recurrent pain occurring in a woman without surgical history, which was eventually diagnosed as an endometrioma (5). Therefore, the final diagnosis can be made only after histologic examination of the mass. One explanation for the cyclic swelling and bleeding of the suprapubic mass in the case reported here may be intermittent inflammation secondary to trauma and resultant rupture of the cyst. The histopathologic differential diagnosis of a suprapubic mass includes epidermoid cyst, sebaceous cyst, cystic teratoma, and dermoid cyst (1). Epidermoid and sebaceous cysts may appear similar to dermoid cysts because they are lined by stratified squamous epithelium. However, they are usually intradermal in location rather than subcutaneous, and they do not contain skin appendages as essential components. Cystic teratomas are composed of tissues derived from more than one germinal plate; they are generally localized in the sacrococcygeal region. Their occasional association with other malformations differentiates them from dermoid cysts. Although the occurrence of a suprapubic dermoid cyst has not been reported to date, four cases of suprapubic pilonidal sinuses with similar clinical features have been reported (6–9). A pilonidal sinus is postulated to be an acquired lesion 724.e6
that results from friction, whereas a dermoid cyst is congenital in origin. Pilonidal sinuses occur most commonly in the sacrococcygeal area. Although it may be difficult to differentiate a pilonidal sinus from a dermoid cyst where the squamous epithelium is replaced by granulation tissue, a pilonidal sinus characteristically forms a sinus tract surrounded by chronic inflammation and fibrotic tissue and does not contain skin appendages. The cyst identified in the case presented here was lined with squamous epithelium and contained skin appendages including hair and sebaceous glands. There were no other nonskin structures identified. The features identified confirmed the diagnosis of a dermoid cyst. In addition, the inflammatory cell infiltrates around the cyst may explain the fluctuation of size resulting from intermittent rupture of the cyst. Treatment requires complete excision of the cyst with primary closure. Although the possibility exists, there have been no cases of malignant transformation of a dermoid cyst reported to date. Our experience with this case illustrates the
724.e7
Kim et al.
Dermoid cyst in the suprapubic area
importance of considering a dermoid cyst in the differential diagnosis of suprapubic wall masses.
REFERENCES 1. Brownstein MH, Helwig EB. Subcutaneous dermoid cysts. Arch Dermatol 1973;107:237–9. 2. Leeming R, Olsen M, Ponsky JL. Inguinal dermoid cyst presenting as an incarcerated inguinal hernia. J Pediatric Surg 1992;1:117–8. 3. Tomasini C, Aloi F, Puiatti P, Caliendo V. Dermoid cyst of the penis. Dermatology 1997;194:188–90. 4. Yoram W, Haddad R. Endometriosis in abdominal scars: a diagnostic pitfall. Am J Surg 1996;62:1042–4. 5. Tomas E, Martin A, Garfia C, Sanchez FG, Morillas JD, Castellano TG, et al. Abdominal wall endometriosis in absence of previous surgery. J Ultrasound Med 1999;18:373–4. 6. MacLeod RG. Pilonidal sinus of the suprapubic region. Br Med J 1953;1: 710–1. 7. Crosby DL. Pilonidal sinus of the suprapubic region. Br J Surg 1962;49: 467–8. 8. Patey DH, Curry RC. Pilonidal sinus presenting in the suprapubic region of a woman. Lancet 1962;1:620–1. 9. Logan G, Edwards SO. Pilonidal sinus of the suprapubic region. Aust NZ J Surg 1971;11:60–2.
Vol. 89, No. 3, March 2008