Lymphoma involvement of the kidney: a retrospective analysis of clinical features, diagnostic approaches and outcomes

Direct involvement of kidney by lymphoma is uncommonly reported. Comprehensive large cohort studies are lacking. Patients with lymphoma involvement of renal parenchyma were retrieved from our diagnostic database from January 1999 to December 2020. Clinical and pathological features are summarized from medical and pathological records. A total of 72 patients were identified including 42 males and 30 females with a mean age of 63.6 years. Diagnostic procedures included fine needle aspiration (FNA), needle core biopsy, nephrectomy, or autopsy, with FNA and core biopsy both highly diagnostic (84% and 98%, respectively). Kidney masses were seen in 69.4%, bilateral kidney enlargement in 9.7%, and no renal imaging abnormality in 20.8%. Fifteen patients underwent nephrectomy with 9 showing lymphoma-only, and 6 with renal cell carcinoma and lymphoma. Most common types of lymphomas were diffuse large B cell ( n = 38), small lymphocytic ( n = 9), marginal zone ( n = 8), and follicular lymphoma ( n = 6) with 8 cases of primary renal lymphoma. In addition to lymphoma involving the renal parenchyma, there was membranous nephropathy ( n = 2), amyloidosis ( n = 1), monoclonal immunoglobulin deposition disease ( n = 1), light chain cast nephropathy ( n = 1), and immunotactoid glomerulonephritis ( n = 1). Forty-five patients received treatment with complete remission in 22, partial remission in 6, initial remission and then relapse in 3, and refractory in 10. Follow-up was 47.8 ± 51.1 months in 62 patients with 18 deaths (29%), of whom the survival period was 16.4 ± 32.4 months (median 4.5 months, range 1-137 months). A variety of lymphomas could involve the kidney with some very aggressive. Striving to reach pathologic diagnosis for renal mass lesions through FNA and/or core biopsy could potentially avoid unnecessary nephrectomy.