The role of cytoreductive surgery for non-genital tract metastases to the ovary

Approximately 6-7% of all adnexal masses found during physical examination are actually metastatic ovarian tumors, which often masquerades as the primary ovarian tumor. The circumstances leading to the discovery of these metastatic lesions depends on the site of the primary tumor. The ovaries may be only slightly enlarged or measure 10 cm or more. Ovarian metastases are bilateral in approximately 70%. The routes of tumor spread to the ovary are variable. Lymphatic and haematogenous metastasis to the ovaries is the most common form of dissemination for the vast majority of cases of carcinoma of the breast, stomach, as well as lymphomas and leukemias. Direct extension is a common manner of spread from colorectum and retropritoneal sarcomas. The ovaries can be reached by the transperitoneal route by cancers from abdominal organs, such as the appendix. Carcinoma of the breast, stomach, colon, and endometrium, as well as lymphomas and leukemias account for the vast majority of cases of metastatic ovarian tumors. In cases, when both ovarian and extraovarian involvement is extensive, determination of the origin of the metastatic ovarian tumor may be impossible. The distinction of metastatic ovarian neoplasm from a primary one is crucial to its subsequent management, and diagnostic misinterpretation may have important adverse consequences for the patient. Although intraoperative frozen-section evaluation is useful Correspondence/Reprint request: Dr. Leszek Gottwald, Chair of Oncology, University Medical School of Lodz Paderewskiego 4 Str., 93-509 Lodz, Poland. E-mail: [email protected] Leszek Gottwald et al. 102 for the diagnosis of metastatic tumors of the adnexa, in some cases it is difficult to distinguish primary ovarian tumors from metastatic ones even by histological examination. In such patients the treatment the treatment should be the same as in primary ovarian carcinoma. The treatment of choice is bilateral salphingooophorectomy, hysterectomy, omentectomy and appendectomy. If there is no gross evidence of abdominal metastasis, pelvic lymph node sampling should be done to determine the extent of disease; In cases when complete resection of the adnexal tumor is impossible, cytoreductive surgery reducing tumor mass before chemotherapy is considered the optimal treatment. The cytoreductive surgery is optimal if the diameter of the largest residual tumor is ≤ 1.0 cm, which is assessed by the maximum tumor in the pelvis and abdomen. In metastatic breast cancer patients ovarian metastases are present in 10-40% of cases, but rarely is the ovarian metastasis evident before the primary tumor is detected. Signs and symptoms of an ovarian tumor are rarely present in patients with breast cancer metastases to the ovaries and microscopic ovarian metastases are occasionally diagnosed at prophylactic oophorectomy by laparoscopy or laparotomy. Ovarian metastases of breast cancer usually are accompanied by other foci of abdominal spread, and the most common treatment modality in such cases is systemic chemotherapy or hormonotherapy. Isolated ovarian metastases occasionally are encountered, and in these cases laparotomy should be performed for optimal cytoreduction. In patients with gastrointestinal cancer the ovarian metastatic tumor is discovered before, or more frequently, at the same time as the gastrointestinal primary. Most of the literature on metastatic ovarian carcinomas from the gastrointestinal tract has concentrated on mucinous, signet-ring cell adenocarcinomas, called Krukenberg tumors. The Krukenberg tumor is almost always secondary to the gastric carcinoma, but may occasionally originate in the large intestine, appendix, breast or other sites. In 35% of patients with a Krukenberg tumor, the diagnosis of the digestive primary precedes the diagnosis of the ovarian metastasis. In these cases the choice of treatment is difficult and prognosis is worse in most cases with fatal outcome in one year. Early diagnosis and complete resection is the only possible hope. Radical operation such as pelvic exenteration can improve survival only in cases of recurrent solitary ovarian metastasis or local extended disease. Colonic adenocarcinomas account for 11-45% of all metastatic ovarian tumors. The addition of prophylactic bilateral oophorectomy as routine in peri-menopausal and post-menopausal women undergoing abdominal surgery for bowel cancer was postulated by many authors. On the contrary, another authors indicated no benefits in survival of these patients. In cases of direct invasion of the contiguous ovary from the colorectal cancer (pT4) or macroscopic metastases (M1) found during the abdominal surgery for bowel cancer the radical resection of ovarian metastases with a curative aim seems to improve overall survival. Women with isolated ovarian metastasis with a long interval between initial diagnosis of colon cancer and recurrence, and women with limited disease that appears amenable to facile surgical resection would seem to be the preferred candidates to cytoreductive surgery. For patients with isolated ovarian metastases from colon cancer the optimal cytoreduction can confer a significant Cytoreductive surgery for non-genital metastases to the ovary 103 survival advantage compared with those patients who are left with bulky residual disease. Primary tumors of the appendix are rare and most of them are unrecognized preoperatively, presenting as appendicits, pelvic masses or with atypical abdominal pain. The ovarian and appendiceal tumors are histologically similar; usually it is difficult to distinguish in intraoperative frozen-section primary ovarian mucinous tumors from metastatic ones, and surgical procedures due to primary epithelial ovarian cancer are treatment of choice. Other rare primary tumors reported in the literature are: malignant lymphoma, malignant melanoma, carcinoid tumors, extragenital sarcomas, tumors of the pancreas, gallbladder and bile ducts, pulmonary and mediastinal tumors, renal tumors, adrenal gland tumors, mesothelioma, and peritoneal tumors. Metastases to the ovary other than those already described are of great rarity. In cases of such tumors surgery in the form of a diagnostic laparotomy for the ovarian mass and for symptom relief is often necessary, but the further management of patients depends upon the site of extent of the primary disease. Numerous studies suggest that resection of metastatic ovarian tumors and cytoreductive surgery play a significant role in improving the survival time in patients with no distant metastasis other than to the adnexa. The benefitial role of cytoreductive surgery in malignant melanoma, as well as malignant lymphoma metastatic to the ovary is not confirmed.