Science and Education Publishing American Journal of Medical Case Reports 2 10 2014 10 23 Simultaneous Presentation of Metastatic Cancer and Primary Hyperparathyroidism - A Case Series 225 226 EN Hiang Leng Tan Department of Diabetes and Endocrinology, Weston General Hospital, Weston-super-Mare, UK Muhammad Imran Butt Najeeb Waheed AJMCR20142107 10.12691/ajmcr-2-10-7 2014 10 05 2014 10 20 2014 10 23 The objective of our two case reports is to increase awareness of the simultaneous occurrence of primary hyperparathyroidism and malignancy in patients that presents with hypercalcaemia. This report reviews the case reports from the history, investigation, treatment and outcome for these two patients. A literature review of the association between malignancy and primary hyperparathyroidism was also performed. Both patients had metastatic cancer and primary hyperparathyroidism but died within months of diagnosis despite treatment for their primary malignancy. This serves as a reminder that these two separate diagnoses do exist, though it did not alter the outcome of our patients. However, we propose that in patients with malignancy who presents with hypercalcaemia and non-suppressed PTH level, further workup should be instigated to rule out primary hyperparathyroidism as surgical option is potentially curative for the latter.