Serous and mucinous ovarian tumors of low malignant potential (LMP-S and LMP-M, respectively) are noninvasive tumors that portend excellent survival when confined to the ovary. Comparison of the survival for women with LMP tumors staged as distant with women who have carcinoma may have important implications for diagnostic terminology and clinical management.

The authors compared relative survival rates among patients diagnosed with ovarian tumors during the period 1988-1999 (with follow-up through 2000) by histologic type, disease stage, tumor grade (for carcinomas), and patient age, using data from the Surveillance, Epidemiology, and End Results Program.

The overall relative survival rate at 10 years (+/- 1.96 standard errors) was 96.9% +/- 2.3% for women with LMP-S tumors, 30.4% +/- 1.7% for women with serous carcinoma (CA-S); 94.0% +/- 3.1% for women with LMP-M tumors, and 64.7% +/- 3.4% for women with mucinous carcinoma (CA-M). The survival rate at 10 years for women with distant-stage LMP-S tumors was 89.9% +/- 5.3%, compared with 96.1% +/- 8.6% for women with well differentiated, localized CA-S. The survival rate for women with distant-stage LMP-M tumors at 5 years was 85.5% +/- 9.0%, compared with 95.5% +/- 3.4% for women with well differentiated, localized CA-M (data for 10 years were limited). Mucinous ovarian neoplasms were associated with an excess of second malignancies of the digestive tract.

Relative survival among women with distant-stage LMP tumors was not 100% and resembled the survival of women who had carcinoma exhibiting favorable prognostic features (localized stage). Future studies of women with high-stage LMP tumors are required to clarify the pathogenesis of extraovarian lesions and their implications for management and prognosis.