The coexistence of cancer cells of different origin within the same lymph nodes.

The coexistence of two differently originating cancer cells within the same lymph node is reported. An 83-year-old male patient died from severe carcinomatous lymphangitis of the lungs five months after gastrectomy for gastric cancer. At autopsy, prostatic cancer metastasis to lymph node was found. Histologically, the prostatic carcinoma cells had a cribriform pattern and the gastric cells showed papillary and tubular features. Immunohistochemically, the former was immunoreactive to prostate specific antigen (PSA) and the latter was stained positively for carcinoembryonic antigen (CEA). Fifty-one of the retroperitoneal and intrapelvic lymph nodes were histologically examined; the coexistence of both types of cancer cells was found in two lymph nodes. Both types were adjoined at the hilum, as was also confirmed by an immunohistochemical double staining technique. These two lymph nodes were located in the pre-aortic and left lateral aortic areas, and they belonged to the terminal lymph node group of both the intra-pelvic and intra-abdominal intestinal organs.