Distinguishing lymph node metastases from benign glandular inclusions in low-grade ovarian carcinoma

In order to properly stage patients with ovarian carcinoma, we are routinely removing and microscopically examining sample aortic lymph nodes in these patients, since aortic lymph node metastases may affect long-term survival. Inasmuch as benign glandular inclusions can be found in pelvic and aortic lymph nodes, we have run into difficulty distinguishing such inclusions from genuine metastases in cases of low-grade or borderline serous ovarian carcinomas. Atypical epithelium in these tumors may closely resemble the lining of benign glandular lymph node inclusions. Moreover, like metastases benign glandular inclusions may grow in the peripheral sinusoid, show epithelial papillae and psammoma bodies, and may even proliferate as small sheets of cells. Just how crucial it is to recognize aortic lymph node metastases in these low-grade tumors will be clarified when the prognostic importance of aortic node metastases becomes understood.