The molecular landscape of prMZL. Histology (hematoxylin and eosin) of a representative case of prMZL. (A) The renal parenchyma is effaced by a vaguely nodular proliferation of small- to medium-sized lymphoid cells with round nuclei, condensed chromatin, and pale cytoplasm. (B) Lymphoepithelial lesions are evident in the urothelium of the renal pelvis. (C) Distribution of somatic mutation burdens in prMZL cases, represented as a box plot across samples. (D) Spectrum of somatic variant classifications in prMZL samples, with frequencies categorized by mutation type, including frameshift deletions, insertions, missense mutations, and nonsense mutations. (E) Oncoplot depicting the mutation profiles of genes frequently altered in prMZL cases. The columns represent individual samples, and rows represent the most commonly mutated genes. The color-coded legend indicates the variant classification, biopsy type, sex, and second differentiation. Percentages on the right indicate the proportion of samples harboring mutations in each gene. f, female; m, male; no., number.