Ovarian Dermoid Cyst and Fibrothecoma with Postmenopausal Bleeding
Ovarian Cyst Postmenopausal Bleeding – The term collision tumor refers to the coexistence of two adjacent but histological distinct tumors with no histological admixture at the interface. Collision tumors involving ovaries are extremely rare.
A collision tumor composed of a dermoid cyst and fibrothecoma is extremely rare in menopausal women. The mechanism of the development of collision tumor is uncertain. During clinical evaluation, differentiation of characters of these ovarian tumors is important to decide appropriate treatment strategies and for good prognosis.
We report an unusual clinical manifestation of the torsion of a dermoid cyst and fibrothecoma in the right ovary with postmenopausal bleeding.
Introduction
Dermoid cysts are the most frequently occurring tumors among ovarian germ cell tumors, accounting for more than 20% of all ovarian neoplasms (Dermoid cysts of the ovary). They present most commonly in women younger than 20 years of age, but sometimes occur in menopausal women at a rate of about 10% to 20%.
Fibrothecomas are ovarian tumors of gonadal stromal origin, mesenchymal cell tumors composed of theca-like elements and fibrous tissue, and account for about 0.4% to 8% of all ovarian tumors (Histologic and immunohistochemical evidence for considering ovarian myxoma as a variant of the thecoma-fibroma group of ovarian stromal tumors).
A collision tumor is defined as a tumor in which the different neoplastic components remain histologically distinct and are separated from each other by narrow stroma or their respective basal lamina. There was a case of a 77 year old woman who presented with postmenopausal bleeding (PNB) due to the torsion of a collision tumor comprising a dermoid cyst and fibrothecoma. See full report at NIH.Gov
Case Report
A 77-year-old postmenopausal woman presented with vaginal bleeding with a week-long history and a large pelvic mass associated with lower abdominal discomfort for 3 months. The patient complained of pain, but had no fever, chills and significant gastrointestinal symptoms. She had gone through menopause at the age of 52 and was not taking any hormone replacement.
She had no significant past medical history, familial history or operation history. On pelvic examination, a relatively hard, movable, non-tender mass as large as a double man’s fist was palpated on the right lower abdomen. The vagina, cervix and uterus were normal. There was no guarding or rebound tenderness.
The hemogram revealed anemia with a hemoglobin level of 9.8 g/dL and a hematocrit of 29.8%. Biochemical investigations, tumor markers and hormonal values were within normal limits. The Pap test was normal although she had never gotten it done before.
Abdominal magnetic resonance imaging (MRI) showed a 12 × 12 × 11.5 cm sized, well-marginated, bilobulated cystic mass with some solid areas in the right pelvic cavity. Endometrial aspiration was done, confirming historically normal proliferative endometrium.
Under general anesthesia, surgical exploration was performed with a suspicion of ovarian tumor. The uterus and left adnexa appeared normal, and a large right ovarian tumor of approximately 12 cm diameter was rotated counterclockwise with a 720 degree arc.
No enlargement of lymph nodes around the mass was found. Right salpingo-oophorectomy was performed for frozen biopsy. After confirming the frozen pathologic results as fibrothecoma and benign dermoid cyst, total hysterectomy and left salpingo-oophorectomy were performed.
Permanent pathological examination demonstrated a collision tumor composed of fibrothecoma and benign dermoid cyst. Macroscopically, the resected tumors in both cases showed a unilocular cystic tumor adjacent to a solid tumor. Microscopically, the cystic tumors were composed of cutaneous tissues and the solid tumors consisted of spindle cells with lipid-rich cytoplasm, arranged in interlacing bundles.
The cystic tumor and the solid tumor were completely separate and no transitional features were recognized histologically. Dermoid cyst is the most frequently occurring ovarian germ cell tumor, accounting for 20% of all ovarian tumors, usually in patients of child bearing age. Unlike all other germ cell tumors, the incidence is variable from infancy to old age.
It may have complications such as rupture, torsion, infection and malignant changes. Malignant changes in benign dermoid cysts have been recorded as occurring in 1.0% to 1.8% of cases, usually in patients older than 40 years of age or menopausal women.
Fibrothecomas are ovarian tumors of gonadal stromal origin, composed of theca-like elements and fibrous tissue. These tumors are usually benign and occur most frequently in menopausal women. Clinically, most patients present amenorrhea, irregular menstruation or atypical postmenopausal vaginal bleeding.
A collision tumor represents the coexistence of two adjacent but histologically different neoplasms occurring in the same organ with completely different basal layers or stroma. Collision tumors occur in various organs such as the esophagus, stomach and thyroid, but they are extremely rare in the ovaries. The most common histologic combination of collision tumors of the ovary consists of teratoma and mucinous tumors.
This study shows that the hormonal changes caused by sex cord stromal tumor can cause postmenopausal uterine bleeding and can have significant influence on collision tumors involving dermoid cysts and fibrothecoma. The torsion of this kind of unique combination of tumors has never been reported, thus this study has its remarkability.
For more information about this report and more information about ovarian cyst postmenopausal bleeding, go to https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5016499/
Credit
Kim JH
1Department of Obstetrics and Gynecology, Institute for Medical Sciences, Chonbuk National University Medical School, Jeonju, Korea.
Www.ncbi.nlm.nih.gov