We report here on a case of metachronous second primary non-Hodgkin's lymphoma (NHL) that was diagnosed 6 years after performing subtotal gastrectomy for treating early gastric cancer (EGC). The subtype analysis revealed mantle cell lymphoma (MCL) of the blastic variant with a leukemic presentation, which was composed of mixed small and medium-sized cells. The immunohistochemical staining for cyclin-D1 was positive. The cytogenetic study revealed t(4;6). In Korea, the risk of developing a second primary cancer following gastric cancer was reported to be less than 3.4%, and NHL comprised less than 6.3% of this second primary cancer. Furthermore, MCL represents about 2% of all lymphomas in Korea. To the best of our knowledge, this is the first report of metachronous primary MCL with a leukemic presentation following curative resection of EGC.

Keywords: Gastric cancer, Metachronous second primary neoplasms, Mantle cell lymphoma, Leukemia