First pathologically confirmed case of concurrent primary renal cell carcinoma and metastatic lung adenocarcinoma in the same kidney

This case underscores the critical importance of histopathological confirmation in complex presentations. It illustrates that even with imaging suggestive of a single primary carcinoma, meticulous pathological evaluation is essential to uncover synchronous MPMNs, thereby guiding precise therapy. The patient demonstrated a positive response to targeted treatment.