Gastric leiomyoma: a tumor in an unusual territory

Leiomyomas are uncommon gastric tumours, especially rare in the cardia. A 71-year-old woman with a past history of follicular thyroid carcinoma presented for routine review. PET imaging revealed a polypoidal mural thickening in the gastric cardia. Radiological impression favoured a gastrointestinal stromal tumour (GIST). Upper GI scopy revealed a submucosal nodule, but biopsy was superficial and non-contributory. The patient underwent surgical exploration with resection of the submucosal nodule and frozen section revealed a spindle cell neoplasm without significant atypia. Grossly, the tumour was firm, grey-white and homogeneous, with intact mucosa. Microscopy revealed spindle cells in intersecting fascicles within a collagenous stroma. Cells had cigar-shaped nuclei, eosinophilic cytoplasm and inconspicuous mitoses. Scattered lymphocytes and mast cells were noted. Immunohistochemistry showed SMA positivity and DOG-1, CD117, CD34 and S100 negativity. Ki-67 index was low (2%), confirming a benign smooth muscle tumour. A final diagnosis of gastric leiomyoma in the rare cardia region was established.