Gallbladder carcinoma with hypoparathyroidism-induced hypocalcemia: A rare presentation

Abstract

Gallbladder carcinoma (Ca GB) is an aggressive malignancy usually diagnosed at advanced stages, with poor prognosis. Hypocalcemia is a known complication in oncology, most often secondary to tumor lysis syndrome, bisphosphonate therapy, or Vitamin D deficiency. Hypoparathyroidism-induced hypocalcemia, however, is exceedingly rare and has not been documented in gallbladder cancer. We report a 37-year-old male who presented with abdominal pain, jaundice, anorexia, and weight loss. Imaging revealed irregular gallbladder wall thickening extending into the extrahepatic bile duct with partial encasement of the right hepatic artery, consistent with stage T4 Ca GB. He underwent percutaneous transhepatic biliary drainage and received gemcitabine-based chemotherapy. Following eight cycles, he presented with acute bilateral lower limb weakness. Laboratory evaluation demonstrated severe hypocalcemia (serum calcium 4.3 mg/dL), low parathyroid hormone (13 pg/mL), and low Vitamin D (14 ng/mL), consistent with hypoparathyroidism induced hypocalcemia. He was treated with calcitriol and calcium supplementation, with marked symptomatic improvement. This case represents a rare association of Ca GB with hypoparathyroidism-induced hypocalcemia. Early recognition and management are essential to prevent morbidity. Reporting such unique presentations expands understanding of paraneoplastic manifestations in gastrointestinal malignancies.