Refractory hypercalcaemia secondary to localised gastrointestinal stromal tumour

Abstract

Gastrointestinal stromal tumours are a rare form of intra-abdominal neoplasm derived from mesenchymal tissue, typically presenting with abdominal pain, anaemia or bleeding into the bowel or abdominal cavity. Hypercalcaemia is an unusual complication, having been documented in only seven previous patients, all of whom had advanced metastatic disease. We present a case of treatment-resistant hypercalcaemia in a patient with non-metastatic gastrointestinal stromal tumour, which resolved following excision of the tumour.

Gastrointestinal stromal tumour-induced hypercalcaemia

“…This patient had localised disease, and following resection, calcium levels stabilised. In this case, there were no abnormalities in PTH, PTHrP or calcitriol, postulating a GIST mechanism independent of calcitriol and PTHrP production 11…”

“…Interestingly, one of the previous cases reported indicated that their patient presented with refractory hypercalcaemia until surgical resection of their GIST 11. This patient had localised disease, and following resection, calcium levels stabilised.…”

“…Table adapted from Hart et al 11GIST, gastrointestinal stromal tumour; PTHrP, parathyroid hormone-related peptide; RFA, radiofrequency ablation.…”

“…GISTs are mesenchymal tumours of the gastrointestinal tract, originating from the interstitial cells of Cajal in the myenteric plexus 10. These tumours can occur at any point along the gastrointestinal tract but most commonly affect the stomach (50–60%) and the small intestine (30–35%) 11. In approximately 80% of cases, the GIST is localised at presentation12; however, malignant potential is variable with around 40% of patients who presented initially with localised disease, developing metastasis 13.…”