5. Discussion: Pathophysiology and Mechanisms of Obstruction

Lymphomatous involvement of the ureter can arise via direct mural infiltration, extrinsic compression from retroperitoneal lymphadenopathy, or less commonly, contiguous spread from adjacent retroperitoneal disease. This array of mechanisms has been described across case reports, stressing that obstruction may result from intrinsic ureteral wall infiltration or extrinsic mass effect, with clinical consequences ranging from reversible obstruction after systemic therapy to persistent renal impairment necessitating drainage or surgical intervention [1–4].