G Girish MD, WK Choo MD, SK Morcos MD
Dermoid cyst, or mature cystic teratoma, is the most common type of ovarian germ cell tumor. It is frequently multi-cystic, and contains sebaceous ﬂuid as well as hair, teeth, bone, and skin. Dermoid cyst is a relatively common ovarian tumor that is an infrequent cause of abdominal and ﬂank pain.
A 36-year-old nulliparous woman presented for right lower abdominal pain that began suddenly 24 h prior. It was severe, colicky pain with radiation to her right ﬂank. She denied anorexia, fever, dysuria, hesitancy, frequency, vaginal bleeding or discharge, or change in bowel habits. Her last normal menstrual period was 1 month prior, and she was on depo-contraceptives. She was sexually active and monogamous. Her examination was signiﬁcant for severe right lower quadrant abdominal tenderness with voluntary guarding, without rebound tenderness. She demonstrated right costovertebral angle tenderness. The pelvic and rectal examinations were normal. Urinalysis demonstrated moderate blood, ketones 80 mg/dL, and a negative beta human chorionic gonadatropin. White blood cell count was 8400 cells per cubic mL, with 85% neutrophils. Ultrasound was done as shown in figure ( 1 &2)
Dermoid cyst is a relatively common ovarian tumor that is an infrequent cause of abdominal and ﬂank pain. Pain when it does occur, is from mass effect and ovarian torsion. These tumors have a classic radiographic and ultrasonographic appearance.
Dermoid cyst, or mature cystic teratoma, is the most common type of ovarian germ cell tumor, comprising up to 30% of all masses (1). They are bilateral in 10–13% of cases (2). The incidence of malignant elements in a teratoma is low (approximately 1–2%) (3). Gonadal dermoid cysts occur mostly during the reproductive years, between the ages of 20 and 40 years (4).
They are frequently multi-cystic and contain sebaceous ﬂuid as well as hair, teeth, bone, and skin. Typically, these tumors contain mature tissues of ectodermal (skin, brain), mesodermal (muscle, fat), and endodermal (mucinous or ciliated epithelium) origin (5). They have a characteristic CT scan appearance with fat/ﬂuid level attenuation and calciﬁcation or ossiﬁcation, as demonstrated in Figure 1 (6). The classic sonographic appearance is of a hyperechoic mass known as a dermoid plug or Rokitansky protuberance, as shown in Figure 2 (7). The Rokitansky protuberance is composed of the thickened area of ectodermal tissue from which hair and teeth arise. Pain is often related to the size of the mass, and ovarian torsion is common. Mature cystic teratomas grow slowly at an average rate of 1.8 mm each year, prompting some investigators to advocate non-surgical management of smaller (6-cm) tumors (8).
In this case, our patient had pyosalpinx on laparotomy. Her pain was likely related not to the dermoid cyst but rather to the pyosalpinx rupture complication in peritoneal cavity. Upon gross dissection surgery, the dermoid demonstrated a classic appearance of a mature cystic teratoma, demonstrating endodermal, mesodermal, and ectodermal tissues. The patient underwent right salpingo-oophorectomy followed by an uncomplicated post-operative course and eventually pyoslapinx also drained.
Mature cystic teratoma is one of the commonest benign cystic lesions in ovary in reproductive age group. Dermoid association with pyosalpinx on the ipsilateral or contralateral side is very rare. Literature reported multiple dermoid cyst but association with pyosalpinx rare in literature.
- Ayhan A, Bukulmez O, Genc C, Karamursel BS, Ayhan A. Mature cystic teratomas of the ovary: case series from one institution over 34 years. Eur J Obstet Gynecol Reprod Biol 2000;88:153–7.
- Comerci JT Jr, Licciardi F, Bergh PA, Gregori C, Breen JL. Mature cystic teratoma: a clinicopathologic evaluation of 517 cases and review of the literature. Obstet Gynecol 1994; 84
- Einarsson JI, Edwards CL, Zurawin RK. Immature ovarian teratoma in an adolescent: a case report and review of the literature. J Pediatr Adolesc Gynecol 2004;17:187–9.
- Scully RE, Young RH, Clement PB. Tumors of the ovary, maldeveloped gonads,fallopian tube and broad ligament. Atlas pathology.Thirdseries,fascicle23.Washington,DC:ArmedForces Institute of Pathology; 1998.
- Outwater EK, Siegelman ES, Hunt JL. Ovarian teratomas: tumor types and imaging characteristics. Radiographics 2001;21:475–90.
- Garant M, Reinhold C. Dermoid cyst of the ovary: computed tomography diagnosis of an unusual case. Can Assoc Radiol J 1996; 47:107–10.
- Exacoustos C, Romanini ME, Rinaldo D, et al. Preoperative sonographic features of borderline ovarian tumors. Ultrasound Obstet Gynecol 2005;25:50–9.
- Caspi B, Appelman Z, Rabinerson D, Zalel Y, Tulandi T, Shoham Z. The growth pattern of ovarian dermoid cysts: a prospective study in premenopausal and postmenopausal women. Fertil Steril 1997; 68:501–5.
Fig 1: USG TAS, showing fat fluid level characteristics of dermoi
Fig 2 & 3: showing Pyosalpinx associated with free fluid and dermoid cyst.