Isolated splenic metastasis from colorectal cancer

Splenic metastases are unusual, arising in less than 1% of all metastases. Isolated solitary splenic metastasis from colorectal carcinoma is considered exceptional. This rarity has been explained by several hypotheses relating to the anatomical, histological, and immunological features of the spleen. We review the reported cases of isolated solitary splenic metastasis from colorectal carcinoma and discuss the diagnostic and therapeutic options for this entity. We searched the English-language medical literature, using the Medline and Pubmed databases from January 1966 through July 2010, for articles reporting isolated splenic metastasis from colorectal carcinoma. Only 26 cases have been reported; four cases had synchronous splenic metastasis. Fifteen patients had regional lymph node involvement on diagnosis of primary carcinoma. The primary tumor was located in the left colon or in the rectum in 18 cases. Carcinoembryonic antigen (CEA) level was elevated in 73% of cases. All patients underwent curative splenectomy; only one patient had laparoscopic resection of the spleen. Mean reported survival interval was 19.5 months; only three patients were deceased at last follow-up. Solitary splenic metastasis from colorectal carcinoma is very rare; clinicians are advised to pay close attention when routinely evaluating patients with serial CEA levels and abdominal scans. Splenectomy seems to be the preferred treatment modality with improvement of long-term survival. However, definitive conclusions cannot be drawn from the small number of case reports available.