High incidence of liver metastasis in gastric cancer with medullary growth pattern.

We studied the histology of resected specimens from 71 gastric cancer patients with synchronous and metachronous liver metastasis to assess the predominance of a particular histological pattern in gastric cancer with a tendency for liver metastasis. Poorly differentiated adenocarcinoma manifesting a medullary growth pattern was the most frequent histologic pattern (33%), followed by papillary adenocarcinoma (28%) in 39 patients with synchronous liver metastasis. In 32 patients who developed metachronous liver metastasis as the main pattern of recurrence, papillary adenocarcinoma was most frequent (47%), followed by poorly differentiated adenocarcinoma of the medullary type (28%). Scirrhous carcinoma was not encountered in patients manifesting metachronous liver metastasis. As most of the papillary adenocarcinomas exhibited a medullary growth pattern, we hypothesize that gastric cancer of the medullary type tends to metastasize to the liver, irrespective of the basic histologic pattern, and that poorly differentiated adenocarcinoma of the medullary type has a particularly high tendency for metastasizing to the liver.