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.

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.

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)

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).