Case Report: Synchronous germline BAP1-negative choroidal melanoma and clear cell renal cell carcinoma characterized...

Synchronous occurrence of choroidal melanoma and clear cell renal cell carcinoma (ccRCC) is exceptionally rare and traditionally suspicious for BAP1 tumor predisposition syndrome. Distinguishing synchronous primaries from metastasis poses diagnostic challenges.

A 64-year-old Chinese male with a 2-year history of progressive vision loss in his right eye was found to have an intraocular melanocytic tumor by multimodal imaging. Staging PET/CT incidentally detected a hypermetabolic mass in the right kidney. Guided by imaging and multidisciplinary team (MDT) discussion, the patient underwent right eye enucleation followed by right partial nephrectomy. Histopathology and immunohistochemistry supported two independent localized primary tumors: mixed-cell choroidal melanoma (AJCC 8th edition stage II, pT2aN0M0) and ccRCC (pT1bN0M0, WHO/ISUP grade 2). Postoperative comprehensive genomic profiling provided supportive molecular evidence, showing a GNAQ p.Q209L driver alteration in the ocular tumor and VHL/PBRM1/SETD2 alterations in the renal tumor. Germline testing of the hereditary cancer predisposition gene set detected no pathogenic or likely pathogenic variants, including BAP1. The patient received no adjuvant therapy and remained disease-free at 21 months after surgery.

This case illustrates that multimodal imaging and multidisciplinary assessment can guide curative-intent management for synchronous early-stage tumors, while postoperative genomic profiling can add supportive molecular evidence and inform genetic counseling. Low-VAF renal genomic findings should be interpreted cautiously and in the context of histology and immunophenotype. Long-term surveillance remains essential.