Non-neoplastic Kidney Diseases in Adult Tumor Nephrectomy and Nephroureterectomy Specimens in a Southeast Asian Tertiary Medical Center

OBJECTIVE: Non-neoplastic kidney diseases are concurrently present in up to 15% of patients with renal and ureteral tumors, which have been most studied in the United States. This study was conducted to determine the prevalence and spectrum of renal parenchymal diseases in similar patients from a Southeast Asian academic institution.METHODS: We searched the database of the Department of Anatomical Pathology, Faculty of Medicine Vajira Hospital, Navamindradhiraj University (2012–2022) and found 194 adult nephrectomy and nephroureterectomy specimens with renal, renal pelvis, and ureteral tumors. Additional stains included periodic acid-Schiff, methenamine silver, and Masson trichrome. Direct immunofluorescence microscopy was performed on the paraffin tissue sections for immunoglobulin (Ig) G, IgA, IgM, and kappa and lambda light chains. Clinical information, including age, gender, and co-morbidities, was obtained from the electronic medical records.RESULTS: Analysis of the 194 cases demonstrated the average age was 61 years (range: 17-89 years), with 126 males (65%) and 68 females (35%). After re-examination of the non-neoplastic renal parenchyma, 14 cases (7%) had diffused and/or nodular mesangial sclerosis. Diabetic nephropathy (12 cases) and idiopathic nodular glomerulosclerosis (2 cases) were diagnosed and associated with either stage 1 or 2 genitourinary cancers. Another case was diagnosed with atheroembolic renal disease. In all cases, the concurrent renal diseases were not identified during the initial evaluation.CONCLUSION: Examination of the non-neoplastic renal parenchyma is important to identify non-neoplastic kidney diseases, such as diabetic nephropathy, so early treatment may result in improved clinical outcomes for kidney and urothelial cancer patients.