Abstract
A 79-year-old woman was being followed for an adenomatous goiter of the thyroid ; cervical lymph node swelling was detected. A lymph node biopsy was performed. A metastatic adenocarcinoma of unknown origin was diagnosed. Despite extensive testing, no evidence of a primary lesion was found. The patient died due to disease progression. On postmortem examination the tumor was found to have grown along the retroperitoneum under the diaphragm from the hypogastrium ; remarkable swelling of the lymph nodes near the aorta was seen. On histology, a retroperitoneal serous adenocarcinoma with a micropapillary structure was diagnosed ; extensive lymph vessel invasion was noted. Immunohistochemistry yielded CA125 positive findings ; the ovaries were negative. Therefore, peritoneal serous papillary adenocarcinoma (micropapillary carcinoma) was diagnosed. Micropapillary carcinoma is primarily related to breast cancer. Micropapillary carcinoma related to peritoneal serous adenocarcinoma has not been previously reported. In this paper our rare case is discussed, and the relevant literature is considered.
