OBJECTIVETo study the clinicopathologic characteristics of metastatic carcinomas to the spleen.

METHODSSixteen cases of metastatic carcinoma to the spleen were retrieved from archival clinical, surgical pathology and autopsy records. The demographic data (including sex and age of patients), clinical symptoms, primary sites, tumor histologic types, gross appearance of spleen and growth patterns within the spleen were analyzed.

RESULTSAmong the 16 patients studied, 12 were males and 4 were females. The male predilection was obvious. The age ranged from 48 to 90 years, the median age 66.5 years. Major clinical symptoms included discomfort in the left upper quadrant, pain, emaciation and loss of appetite. Splenomegaly was noted in some patients and computerized tomography could show space-occupying lesions in the spleen. In general, lung was the most common primary site for splenic metastasis and accounted for 43.8% of all cases (7/16). In male patients, primary lung tumor was found in 50.0% cases (6/12). On the other hand, primary ovarian tumor was commonly seen in females (2/4). Histologically, undifferentiated carcinoma of lung was frequently encountered (25.0%, 4/16), including 3 cases of small cell undifferentiated carcinoma and 1 case of large cell undifferentiated carcinoma. Other histologic tumor types included bronchioloalveolar carcinoma (2 cases), colonic adenocarcinoma (2 cases), ovarian serous papillary adenocarcinoma (2 cases), and prostatic adenocarcinoma (2 cases). The commonest histologic tumor type found in male patients was pulmonary undifferentiated carcinoma. The growth patterns of metastatic carcinoma in spleen included nodular, diffuse and multinodular. Most cases presented as a single splenic nodule. Sometimes, tumors with high metastatic potential (5/16) showed diffuse and multinodular growth patterns. Examples of these tumors included small cell undifferentiated carcinoma (3 cases), pulmonary adenocarcinoma (1 case) and prostatic adenocarcinoma (1 case).

CONCLUSIONSMetastatic carcinoma to the spleen is rare. Understanding of the clinicopathologic characteristics is helpful in guiding clinical management and pathologic diagnosis.