Obstetrics and Gynecology/Ovarian Neoplasia

Epidemiology With respect to general ovarian neoplasms, 30% of postemenopausal women with adenexal masses have malignant disease, compared to 7% in pre-menopausal women. Benign Neoplasia The vast majority of young women who present with adenexal masses have functional ovarian cysts. Dermoid cysts and serous cystadenomas are tied with respect to the incidence of tumor etiology in reproductive age women. Ovarian Cancer The median age of diagnosis for ovarian cancer in Canada is 56 years of age. 50% of ovarian masses in women over 50 years of age are malignant. 75% of women are diagnosed at stage III cancer because of delayed presentation of ovarian cancer symptoms. 1/70 women will develop ovarian cancer in their lifetimes. Ovarian cancer is the leading cause of gynecological death in North America. Ovarian cancer is the 5th most common malignancy in North America 90% of all ovarian cancers are epithelial ovarian cancers, 80% of which are serous papillary carcinomas. 10-15% of all ovarian cancers are hereditary in origin. Etiology and Risk Factors Possible etiologies of the adenexal mass: Gastrointestinal tract: bowel cancer, constipation, bowel abscess Urinary tract: full bladder Obstetrical/Gynecological: pregnancy, hydrosalpinx, tubal cancer, fibroids, ovarian cancer Benign Ovarian Tumors Functional ovarian cysts arise from ovulatory failure, growth, and rupture of the graffian follicle. Endometriomas arise from cyclic bleeding of ectopic endometrium. Dermoid cysts arise from oocytes. Epithelial Ovarian Carcinoma Epithelial ovarian tumors arise from the peritoneal coverings of the ovaries. Risk factors: Nulliparity Early menarche Late menopause Age over 40 Family history of breast, colorectal, or ovarian cancer BRCA 1 or 2 mutations Oral contraceptive use, hysterosalpingectomy, breast feeding, and tubal ligation are protective factors. Clinical Presentation and Diagnostic Approach Presentation of the Adenexal Mass Women may present with Most cases are discovered incidentally and present with vague symptoms Postmenopausal bleeding Dyspareunia Acute pain in pelvis and lower abdomen Urinary frequency, urgency Constipation Bowel obstruction Ascites Omental masses Pleural effusion Local lymphadenopathy Palpable adenexal masses Diagnostic Approach to the Adenexal Mass Pelvic and abdominal ultrasound Benign disease will usually present as a mass <8cm in size, cystic in consistency, and unilateral Malignant disease will typically present as a mass >8cm in size, solid and cystic in consistency, and bilaterally. Furthermore, ascites, omental lesions, and enlarged lymph nodes may be visualized: all of which suggest a malignant etiology. CT scanning (MRI rarely used for this purpose) Ca-125 measurement (if required equipment) CBC + differential: if anemic, thorough workup should be completed for a gastrointestinal pathology. Creatinine Laparotomy and biopsy. Laparotomy is performed according to the following guidelines Cancer without evidence of spread: excision of lesion, omentum, and regional lymph nodes for staging Cancer with evidence of abdominal spread: excision of all lesions greater than 1cm Typically involves a total hysterectomy, salpingectomy, oophorectomy If bowel obstructed or infiltrated, small and/or large bowel resection is indicated Laparoscopy and biopsy if laparotomy not done. Percutaneous aspiration and paracentesis with cytology performed. Pathology, Histology, and Staging Ovarian Cancer Epithelial ovarian tumours (90% of ovarian cancer) Serous papillary tumors (80* of ovarian cancer) Mucinous Endometrioma (high malignant potential)/clear cell Mixed tumours Germ cell tumours Immature teratoma Dysgeminoma (produces LDH) Yolk sac tumors (produces AFP) Embryonal carcinoma (AFP and hCG) Choriocarcinoma (produces hCG) Stromal tumours Sertoli-Leydig (produces testosterone) Granulosa cell (produces estrogen) Staging Simply put Stage 1: confined to the ovary (survival 90% at 5yr) Stage 2: confined to the pelvis (survival 60-75% at 5yr) Stage 3: confined to the abdomen, without invasion of liver parenchyma (survival 30-40% at 5yr) Stage 4: invasion of liver parenchyma and/or beyond (survival 10% at 5yr) Management Functional Ovarian Cyst Reevaluate in 1-2 months. If no resolution in 6-8 weeks, refer to specialist. Ovarian Cancer If BRCA 1 positive, prophylactic surgery at age 35. If BRCA 2 positive, prophylactic surgery at menopause. There is approximately a 5-10% chance of finding tubal cancer at surgery. Stage I, Grade I-II cancer, follow postoperatively (see operative indications in Approach. All other grades and stages may only be treated with chemotherapy (Carbo/Taxol).