Double hit: Synchronous gastrointestinal stromal tumour (GIST) & lung neuroendocrine tumour − a rare case of multiple primary malignancies

Gastrointestinal Stromal Tumours (GISTs) are rare but remain the most common mesenchymal tumour of the Gastrointestinal tract (GIT). The asynchronous occurrence of other malignancies in patients with GIST during the clinical course is relatively common. However, the synchronous coexistence of GIST and lung cancer has only rarely been reported. We report the case of a 65-year-old male, a former smoker, who was diagnosed with synchronous occurrence of mesenteric GIST and Primary Large Cell Neuroendocrine Cancer (LCNEC) of the lung. There are few case reports on synchronous occurrence of GIST with primary lung cancer but till date no case report exists on GIST with primary LCNEC of lung.