Clinical, pathological and loss of heterozygosity differences in Wilms tumors between Asian and non‐Asian children

Wilms tumor demonstrates significant interethnic epidemiological, histological and outcome differences, and is rare and poorly studied among Asians. We compared the clinicopathological, and loss of heterozygosity (LOH) profile and survival outcomes of Asian and non‐Asian patients with Wilms tumor. Clinical charts and histological slides from patients with malignant renal tumors over a period of 20 years were retrospectively reviewed. We adapted a genotyping assay to determine 1p36 and 16q21‐22 LOH in formalin‐fixed paraffin‐embedded (FFPE) specimens, and compared these characteristics between Asian and non‐Asian patients. Fifty‐three (79.1%) Asian and 14 (20.9%) non‐Asian patients had Wilms tumors. Compared to non‐Asians, Asians were younger (mean 4.6 and 4.0 years, respectively), had more equal gender distribution (female: male = 1.8 and 1.0, respectively), fewer tumors with unfavorable histology (25.0% and 4.1%, respectively, p = 0.05), and less advanced disease at presentation, yet similar nodal metastases rates (16.7% and 18.4%, respectively). No Asian patients had bilateral tumors. Our adapted genotyping assay accurately determined LOH in FFPE specimens