Clinical Features and Outcomes of Spontaneous Tumor Lysis in Testicular Germ Cell Tumors: A Case Series From a Cancer Center in Lahore, Pakistan.

Background Testicular germ cell tumors (TGCTs) are the most common solid malignancies in young adult men and typically have excellent outcomes with modern therapy. Tumor lysis syndrome (TLS) is a rare but potentially fatal complication in TGCTs, particularly when it occurs spontaneously in the absence of cytotoxic treatment. Data describing spontaneous TLS in this setting remain limited. Methods We report a case series of six patients who presented with spontaneous TLS secondary to TGCTs. Clinical features, imaging findings, laboratory results, management strategies, and outcomes were reviewed retrospectively from the electronic medical records. TLS was diagnosed based on characteristic biochemical abnormalities, including hyperuricemia, hyperphosphatemia, hyperkalemia, hypocalcemia, and acute kidney injury (AKI). Results Most patients had seminomatous histology, and all demonstrated extensive tumor burden on imaging. TLS was identified prior to the initiation of chemotherapy in all cases. Management included aggressive intravenous hydration, urate-lowering therapy with rasburicase and/or allopurinol, and renal replacement therapy for refractory metabolic disturbances. Chemotherapy was initiated with individualized dosing strategies to minimize further metabolic complications. Despite early recognition and multidisciplinary management, mortality was substantial, largely due to renal failure and infectious complications. Conclusions Spontaneous TLS is a rare but life-threatening complication of TGCTs, particularly in patients with bulky disease. Tumor burden appears to be a key risk factor regardless of histological subtype. Increased clinical awareness, early diagnosis, aggressive supportive care, and tailored chemotherapy approaches are critical to reducing morbidity and mortality in this high-risk population.