Emergencies due to malignancies usually have a severe clinical course and require urgent treatment. These scenarios are dubbed 'oncologic emergencies'. Parathyroid tumours often cause hypercalcaemia but not oncologic emergencies. We present a case of parathyroid carcinoma with severe hypercalcaemia and pancreatitis, resolved by surgical resection of the tumour assisted by extracorporeal membrane oxygenation (ECMO). A 66-year-old woman presented to our hospital because of haematuria. Laboratory findings were as follows: white blood cell count: 30 000, C-reactive protein: 17.7, calcium: 21.9, creatine kinase: 316, creatine kinase-myoglobin binding: 20, troponin I: 1415.8, amylase: 1046, lipase: 499, blood urea nitrogen: 57, and creatinine: 2.42. ECG was unremarkable. CT revealed a 4-cm low-density irregular tumour in the left lobe of the thyroid gland and severe pancreatitis. We diagnosed hypercalcaemia and pancreatitis due to parathyroid carcinoma. Volume expansion with isotonic saline was started immediately. Calcitonin, followed by denosumab, calcimimetic agents, and continuous hemodiafiltration were administered. The patient's general condition worsened due to uncontrolled hypercalcaemia. Urgent tumour resection was planned, assisted with ECMO for cardiopulmonary support and surgical field venous pressure reduction. Tumour histology was suggestive of parathyroid carcinoma. Hypercalcaemia and the patient's general condition improved gradually postoperatively. Hypercalcaemia is one of the oncologic emergency symptoms, commonly occurring because of lytic bone metastasis. However, reports about parathyroid carcinoma-causing life-threatening hypercalcaemia and pancreatitis are scarce; the fatality of this condition is estimated to be 30-70%. We report a case of survival of hypercalcaemia of malignancy. Parathyroid carcinoma is relatively rare and sometimes causes emergent conditions such as hypercalcaemia and severe pancreatitis. General therapy for hypercalcaemia including aggressive saline dehydration, administration of furosemide, calcitonin, zoledronic acid, and evocalcet, and dialysis is sometimes ineffective for parathyroid carcinoma. Therefore, careful planning of therapy in case of exacerbation is important. During an emergency, rapid surgical treatment despite high calcium level is the best potential therapeutic strategy.