For a study, researchers sought to assess whether VHL mutation analysis can distinguish between cases that represent multiple independently arising primary tumors or a single primary tumor that has spread ipsilaterally as well as to the contralateral kidney in patients with bilateral, multifocal clear cell renal cell carcinoma (ccRCC). It was unclear what causes kidney cancer multifocality outside of established genetic disorders.

DNA samples from multiple tumors were examined for somatic VHL gene hypermethylation and mutation for each patient. In addition, targeted, next-generation sequencing tests were used to study a group of cancers with common VHL mutations.

About 5 patients with multiple tumors that shared a somatic VHL mutation and evidence of metastatic dissemination, including to the opposite kidney, were included in the cohort. In addition, it was supported in various instances by additional common somatic mutations in genes related to ccRCC. The remaining 14 patients, on the other hand, had distinct, unrelated VHL changes in every tumor examined, which was consistent with independently developing kidney cancers. In addition, none of the patients in the latter group had any evidence of regional dissemination or distant metastases.

A single patient’s examined bilateral; multifocal ccRCC tumors have a span of VHL changes that can differentiate between different independent tumor development and metastasis. In addition, clinical genetic tests that are already on the market might be used to conduct it, increasing the precision of patient diagnosis and prognosis and providing useful treatment information.

Reference: goldjournal.net/article/S0090-4295(22)00303-X/fulltext