Abscess formation mimicking disease progression, in a patient with metastatic renal cell carcinoma during sunitinib treatment

BACKGROUND Renal cell carcinoma (RCC) represents approximately 3% of all adult cancers and is more common in males. Systemic treatment for RCC has improved following the introduction of tyrosine kinase inhibitors, such as sunitinib. The molecular targets of sunitinib are receptor tyrosine kinases (RTKs). Moreover, sunitinib has an additional anti-angiogenic effect through its inhibition of the vascular endothelial growth factor receptor activation. CASE PRESENTATION We present a case of intra-abdominal abscess formation mimicking disease progression, in a patient with metastatic renal cell carcinoma during sunitinib treatment. CONCLUSION In the advancing era of molecular therapy of solid tumours, sunitinib has demonstrated significant efficacy in the post-cytokine setting treatment of metastatic renal cancer. Concurrently, however, increasing evidence has emerged to indicate that this class of drugs exert profound immunomodulatory effects on T cells and play major roles in immune tumor surveillance.