Primary lymphoma of the kidney: Pathology experience from 2 tertiary hospitals in Western Saudi Arabia

OBJECTIVES: To document the clinicopathological features of primary renal lymphoma (PRL) at 2 tertiary hospitals in the western region of the Kingdom of Saudi Arabia. METHODS: Data were retrieved from all PRLs that were diagnosed at King Abdulaziz University Hospital and King Faisal Specialist Hospital and Research Centre, Jeddah, Saudi Arabia, between January 2002 and April 2022. Histopathological and immunohistochemical slides were reviewed, and additional immunohistochemistry stains were carried out in selected cases. Follow-up data were also collected. RESULTS: There were 17 identified cases of PRL. The age of the patients ranged from 4-76 years (median: 50.5 years and mean: 46.8 years), 11 (64.7%) were males, and 6 (35.3%) were females. There were 12 cases of diffuse large B-cell lymphoma, 3 cases of Burkitt’s lymphoma, and 2 cases of post-transplant lymphoproliferative disorder. The median follow-up duration was 22 months. The one-year overall survival rate was 71% and the 2-year overall survival rate was 43% during follow-up. CONCLUSION: Primary renal lymphomas in Saudi patients are more common in males and seen in a relatively younger age group compared to the available worldwide data. The diagnosis of PRL is important to avoid tumor dissemination and unnecessary nephrectomy. Diffuse large B-cell lymphoma is the most common pathological type and non-germinal center B-cell is the most common subtype.