Autoimplants in serous borderline tumors of the ovary: a clinicopathologic study of 30 cases of a process to be distinguished from serous adenocarcinoma.

The clinical and pathologic features of serous borderline tumors (SBTs) with autoimplants (AIs) were studied with emphasis on their relation to survival, ovarian SBT with a micropapillary pattern, and their distinction from serous adenocarcinoma. The 30 patients ranged in age from 17 to 70 years (mean, 35.8 years). Two had stage I disease, 10 had stage II disease, and 18 had stage III disease. Twenty-five patients had bilateral ovarian tumors. In 28 cases, AIs were present on the surface of the neoplasm or between exophytic surface tumor papillae; in 2 cases, AIs were between papillae within intracystic tumor. The AIs consisted of single cells or glands and clusters of cells with mild to moderate nuclear atypia within a fibroblastic stroma; the stroma dominated over the epithelium in extent within the AI. In many cases, the epithelial cells in the AI had abundant eosinophilic cytoplasm. All but 2 of the patients had coexisting noninvasive peritoneal implants; 3 of them also had invasive peritoneal implants. Six of the SBTs had a micropapillary pattern; 3 of these were stage III and 3 stage II tumors. Clinical follow-up was available for 11 patients. Eight were alive and well after 4 to 7 years (mean, 5 years); 3 of these patients had stage II disease and 5 had stage III disease. Three were dead of disease after 7 to 12 years (mean, 9 years). Two patients who died of disease had stage III disease, and 1 of them had invasive implants. The third patient had stage II disease, invasive implants, and the tumor was of the micropapillary type. Our study indicates that the majority of patients with SBT with AI have stage II or III disease and abundant exophytic tumor. SBTs with AI had a micropapillary pattern in 20% of the cases. AIs do not appear to have an adverse impact on survival when controlled for peritoneal implant type and for this reason must be distinguished from true stromal invasion in serous carcinoma, a misdiagnosis sometimes made, or seriously entertained, initially in these cases. Features that favor AI over carcinoma arising in an SBT are 1) a location between tumor papillae or on the ovarian surface 2) a predominance of stroma over epithelial cells, and 3) the "borderline" cytologic appearance of epithelial cells.