Ovarian Germ Cell Tumor
Borderline ovarian tumors are a subset of epithelial ovarian tumors that have a very favorable prognosis. The accepted initial treatment is surgical removal of the tumor and biopsies. However, the postoperative management protocol is far from clear. To date, no medical therapy has been shown to clearly improve outcomes.
History of the Procedure
In 1929, Taylor first described a subset of ovarian tumors that he termed semimalignant. These lesions had a more favorable outcome than other ovarian cancers, but they were not separately classified by the Federation of Gynecology and Obstetrics (FIGO) and the World Health Organization (WHO) until the early 1970s.
One woman in 55 (1.8%) develops some form of ovarian cancer in her lifetime. Approximately 90% of these cancers are tumors of epithelial origin. If benign lesions are included, epithelial tumors account for 60% of all ovarian tumors. Borderline tumors comprise approximately 15% of all epithelial ovarian tumors. The mean age of occurrence is approximately 10 years younger than that of women with frankly malignant ovarian cancer. Factors reportedly linked with borderline tumors include oral contraceptive use, menarche, age at first pregnancy, age at first delivery, menstrual history, smoking, and family history of ovarian cancer, although none of these has been shown to be statistically significant.
Borderline ovarian cancer is staged according to the FIGO classification of ovarian cancer. Many clinicians group stages II-IV together for prognostic consideration. Another common component of staging is the description of the type of implants, as these have significant prognostic value. As opposed to its true malignant counterpart, epithelial ovarian carcinoma, borderline ovarian cancers are often found at early stages.
The etiology of this disease remains unclear because of the small number of cases and the lack of randomized controlled studies. Based on molecular studies, some mucinous borderline tumors of the ovary may actually represent metastasis from the appendix.
The 2 major histologic tumor subtypes are serous and mucinous, with serous being more common. Serous tumors are presumed to originate from the germinal epithelium. Mucinous tumors do not have a clearly defined origin. Substantial information indicates that many tumors may actually originate from the appendix; thus, this organ should be removed at time of surgery.
These tumors, as with other ovarian tumors, are difficult to detect clinically until they are advanced in size or stage. In one study, the most common presenting symptoms were abdominal pain, increasing girth or abdominal distension, and abdominal mass. Approximately 23% of patients were asymptomatic.
When a complex ovarian mass is discovered, surgery is often, if not always, indicated. Preoperatively, borderline tumors are often presumed to be either benign or malignant ovarian masses; regardless, surgery is required to determine the type of mass.
Contraindications to surgery include medical reasons (ie, the patient is too great a surgical risk secondary to other medical problems) or patient refusal. Otherwise, the masses should be surgically removed.