Splenic metastases in a large unselected autopsy series.

We analyzed the files of all autopsies performed at the Institute of Pathology of the Philipps-University Marburg between 1980 and 1999 with respect to the presence of splenic metastasis. The total number of autopsies within the study period was 8,563. In 1,898 cases, a solid malignant tumor (1,774 carcinomas, 36 sarcomas, 27 malignant melanomas) was diagnosed. Metastasis to the spleen occurred in 57 cases (3.0%). Compared to the whole study population, patients with splenic metastasis were significantly younger (59 years vs. 67 years, p<0.05) and had significantly more metastastic sites (median: 6 vs. median:1, p<0.05). This underlines the assumption that splenic metastasis is associated with a worse prognosis. Lung cancer, cutaneous malignant melanoma, and breast cancer were the most frequent primary tumors, accounting for 24.6%, 15.8%, and 12.3% of all spleen metastases, respectively. Patients with testicular germ cell tumors (patients: 9, spleen metastasis: 4), malignant melanoma (patients: 27, spleen metastasis: 9, 33%), and small cell lung cancer (patients: 106, spleen metastasis: 8, 7.5%) had the highest frequency of splenic involvement. Most (n=48) metastases were detected macroscopically, the remaining ones were micrometastases (n=2), small tumor cell clusters, and single tumor cells within sinusoids (n=7). The present study underlines the importance of spleen metastasis as an indicator of poor prognosis. There are, however, various aspects as to the detection and morphology of spleen metastasism, which merit further scrutiny.