A RARE CASE OF MALIGNANT HYPERCALCEMIA WITH SPONTANEOUS TUMOR LYSIS IN METASTATIC MIXED GERM CELL TUMOR

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Malignant Hypercalcemia (MH) and Tumor Lysis Syndrome (TLS) are considered major oncologic emergencies. MH at initial presentation is associated with a poor prognosis (1). We present unique case of Mixed Germ Cell tumor an spontaneous TLS hypercalcemia instead hypocalcemia. CASE PRESENTATION: A 24-year-old male no significant past medical history presented abdominal pain, vomiting, anorexia, dyspnea for 3 months. Patient had painless testicular mass two years. Vital signs were unremarkable except Temperature 101.8F. Physical exam showed bilateral enlargement (~15cm) mild tenderness to palpation. large right-sided was palpated. Labs elevated creatinine (Cr) 2.0, phosphorus 4.9, calcium 14.4, uric acid (UA) 10.8, Alpha fetoprotein 716, lactate dehydrogenase 772. Parathyroid hormone low 2.7; potassium hCG normal. CT scans 16cm retroperitoneal areas necrosis hemorrhage effect causing right hydronephrosis, multiple lung nodules diffuse lytic lesions. Aggressive intravenous fluids, bisphosphonates calcitonin administered. received Allopurinol TLS. underwent radical orchiectomy urethral stent placement. Pathology mixed germ cell extensive sarcomatoid transformation. Serum protein electrophoresis ruled out myeloma. Cr UA levels normalized, significantly improved. currently on chemotherapy Cisplatin Etoposide plan retro-peritoneal lymph node resection after 4 cycles treatment. DISCUSSION: paraneoplastic syndrome seen in 20-30% patients malignancy common solid tumors (2). Paraneoplastic can be PTHrP mediated, osteolysis due bone metastasis, ectopic PTH, calcitriol secretion (3). Osteolytic metastases possible cause malignant our given the normal PTH levels. rarely subsolid tumors, particularly tumors. Though hypocalcemia usually TLS, high turnover, metastatic burden, or sensitivity chemotherapy, (4) as case. Treatment mainly prevention based risk stratification (5) initiating timely therapy hydration measures, correcting electrolyte metabolic disturbances. Initiating Rasburicase dependent. Data suggests surgical carries excellent (5 year survival 94.9%) (5). CONCLUSIONS: typically presents co-occurrence rare prognosis. REFERENCE #1: Clines GA, Guise TA. Hypercalcaemia basic research mechanisms responsible osteolytic osteoblastic metastasis bone. Endocr Relat Cancer. 2005 Sep;12(3):549-83. #2: Gastanaga VM et al. . Prevalence among cancer United States. Cancer Medicine 2016;5:2091–100. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4899051/ #3: National institute, stat facts-testicular https://seer.cancer.gov/statfacts/html/testis.html DISCLOSURES: No relevant relationships by Dilesha Kumanayaka, source=Web Response Amy Paige, Hamid Shaaban, Divya Mounisha Thimmareddygari, Sindhusha Veeraballi,