Presentation
Acute right sided abdominal pain.
Patient Data
The vermiform appendix is thickened and surrounded by extensive stranding in the surrounding fat. There is no abscess formation or free intra-abdominal air.
Additionally left upper pole renal mass is present consistent with a renal cell carcinoma. The fat plane between the left crus of the diaphragm and the splenic artery above the mass is lost, which is suspicious for local invasion.
Thickened appendix (yellow) is surrounded by extensive stranding in the adjacent fat in keeping with inflammation. The left kidney has a large heterogeneous upper pole mass (blue) consistent with a RCC, with likely extension beyond Gerota's fascia (red).
Case Discussion
Although clearly this patients presentation is due to acute appendicitis, a painless and asymptomatic large renal cell carcinoma is also visible. The crucial lesson to learn is to not merely look for the answer to the clinical question but also take the opportunity to identify asymptomatic incidental lesions.