Distinguishing splenosis from local recurrence of renal cell carcinoma using a technetium sulfur colloid scan

Heterotropic splenic tissue in renal fossa is characteristically asymptomatic and is usually an incidental finding that has been reported to mimic renal or adrenal tumors. A 55-year-old man with renal cell carcinoma had undergone radical nephrectomy together with splenectomy because of disrupture of the splenic capsule. During a follow-up examination, three nodules were detected by computed tomography scan in the splenorenal area and they slowly enlarged. Although local recurrence was highly suspected, we decided to rule out splenosis. We successfully diagnosed these masses as ectopic splenic tissues by a technetium sulfur colloid scan and unnecessary surgical exploration was avoided.