PURPOSE:The aim of this study was to investigate changes in spleen size, the level of chromogranin Aas a tumor marker, and the relationship between these two parameters before and 3 months after selectiveinternal radiation therapy (SIRT) for non-resectable liver metastases from neuroendocrine tumor (NET).Our first serious adverse event with this relatively new treatment is also discussed.METHODS:A retrospective review of a prospective database identified patients with non-resectable livermetastases from NET who underwent SIRT between 2003 and 2007. Patients who underwent CT scansbefore and 3 months after treatment were included. The patients were divided into two groups:those withand without a 20 % or more increase in splenic volume on the CT scans. The percentages of patients showinga tumor marker response in the two groups were then comparedRESULTS:Fourteen patients were included in the present analysis. A tumor marker response was seenin 6 of 7 patients( 85.7%) who showed an increase in splenic volume of>20%, and in 3 of 7 patients( 42.9%) without an increase in splenic volume (p=0.266). There was one death as a result of oesophageal varicealbleeding due to portal hypertension at 9 months after treatment.CONCLUSION:Splenic enlargement after SIRT may be associated with tumor marker response, althoughthis could not be confirmed statistically in this study due to the small number of patients. Long-termsplenomegaly and portal hypertension may be important complications of SIRT. This issue needs to be investigatedfurther using a larger number of patients and longer follow-up
