Metastatic tumors to the spleen: a 25-year clinicopathologic study.

OBJECTIVE: The clinicopathologic features of splenic metastases have seldom been investigated. The aim of this study was to evaluate the clinical and pathological impact of splenic metastases. CASE MATERIAL: We reviewed the clinical/autopsy records and pathologic features of 92 Chinese patients (58 men, 34 women) with secondary nonlymphoid splenic tumors recorded during a 25-year period.
RESULTS: The incidence of splenic secondary tumors at autopsy was 0. 6% and at splenectomy, 1.1%. The lesions were often seen in elderly patients (mean age, 60 years). Seven (8%) of the splenic lesions were symptomatic. The symptomatic splenic lesions, as compared with asymptomatic lesions, were bigger and were found more often in women and younger patients. Two patients experienced spontaneous splenic rupture because of metastatic carcinoma. Eighty-seven (95%) of the secondary splenic tumors were carcinomas. Lung was the most common primary tumor site (21%), followed by the stomach (16%), pancreas (12%), liver (9%), and colon (9%). Rarely reported sources of primary tumor, such as esophageal carcinomas, nasopharyngeal carcinoma, and choriocarcinoma, were also found. Splenic metastases could be identified macroscopically in 74 (80%) of our patients. Grossly, splenic metastases involved the splenic capsule (n = 8) or were solitary (n = 31), multiple (n = 30), or diffuse (n = 8) lesions in the splenic parenchyma. Isolated splenic metastases were noted in 5.3% of the metastases found at autopsy. Many of the metastatic lesions in the spleen were identified shortly after primary tumors were detected (mean latent period, 6.7 months). The time from diagnosis of the primary tumor to metastasis to the spleen was more than 2 years in 14 patients.
CONCLUSIONS: Splenic metastases are uncommon. A variety of clinical and pathologic patterns were noted in our series.