Fig. 5: Representative photomicrographs from two synchronous tumors arising in the right kidney of a 22-year-old woman with a known germline SDHB mutation.

The largest tumor was 10 cm and demonstrated the stereotypical low-grade features of SDH-deficient renal carcinoma (A, B). In contrast, the second tumor measured 4.5 cm and exhibited widespread high-grade morphology including occasional rhabdoid cells (C). Focal intracytoplasmic inclusions were identified in the high-grade tumor after careful inspection (D). The patient died of disease 27 months after diagnosis.