# A Case of Metachronous Prostate Adenocarcinoma and Chromophobe Renal Cell Carcinoma in a Nigerian Male Patient: Diagnostic and Therapeutic Challenges

## TL;DR

A 69-year-old man developed prostate cancer and later chromophobe renal cell carcinoma, highlighting the need for careful diagnosis and follow-up in complex urologic cases.

## Contribution

This case report highlights the rare co-occurrence of two distinct urologic cancers and emphasizes the importance of immunohistochemistry in accurate diagnosis.

## Key findings

- The patient was diagnosed with acinar adenocarcinoma of the prostate (Gleason 4+3) and later with chromophobe renal cell carcinoma.
- Immunohistochemistry confirmed the renal tumor as the eosinophilic subtype of ChRCC, underscoring its diagnostic value.
- The case underscores the need for thorough histopathologic evaluation and long-term follow-up in patients with complex urologic histories.

## Abstract

Prostate adenocarcinoma and chromophobe renal cell carcinoma (ChRCC) are two distinct urologic malignancies with different prognoses and treatment approaches. The occurrence of both tumors in the same individual is highly unusual. We describe the case of a 69-year-old man with a long-standing history of hypertension who had previously undergone prostatectomy for benign prostatic hyperplasia. In 2022, he re-presented with recurrent lower urinary tract symptoms. Biopsy confirmed acinar adenocarcinoma of the prostate (Gleason 4+3), and magnetic resonance imaging (MRI) staged the disease as T3aN0M0. He was treated with high-dose-rate (HDR) brachytherapy followed by external beam radiotherapy (EBRT). Two years later, a right renal mass was detected. While the initial histology favored oncocytoma, immunohistochemistry revealed strong cytokeratin (CK)7 expression with focal CD117 staining, confirming the eosinophilic subtype of ChRCC. This case illustrates the importance of thorough histopathologic work-up of renal lesions, the diagnostic value of immunohistochemistry, and the need for careful follow-up in patients with complex urologic histories.