Case Report: A rare case of CD20-positive T-cell large granular lymphocyte leukemia with renal cell carcinoma: a challenging diagnosis

Large granular lymphocytic leukemia (LGLL) is a clonal lymphoproliferative disease with a slow course and considerable difficulties in correct diagnosis and therapy. T-LGLL is the most prevalent subtype of LGLL, accounting for approximately 85%. T-LGLL co-existence with solid malignancies is relatively rare. CD20-positive T-cell neoplasm is a rare disease in clinics. In this study, we report a case of CD20-positive T-LGLL with renal cell carcinoma (RCC) that was eventually diagnosed by splenectomy and nephrectomy. The accumulation of cases will contribute to diagnosing and treating CD20-positive T-LGLL complicated with solid tumors.