Leiomyoma is a well-circumscribed benign smooth muscle neoplasm histologically characterized by the presence of spindle cells with cigar-shaped nuclei, interlacing fascicles, and a whorled pattern.
Gastric intramural leiomyoma
This tumour is rare, approximately 50 times less common than gastrointestinal stromal tumor (GIST)
. These tumours usually occur in older adults and clinically present similarly to GISTs. The tumours vary from minimal mural nodules to masses of >5cm in size. However, minimal leiomyomas have been commonly found in oesophagogastric resections for carcinoma
Abraham SC, Krasinskas AM, Hofstetter WL, Swisher SG, Wu TT (2007)
. Histologically, these tumours are composed of well-differentiated smooth-muscle cells with no or little atypia and mitotic activity, or isolated mitosis.
"Seedling" mesenchymal tumors (gastrointestinal stromal tumors and leiomyomas) are common incidental tumors of the esophagogastric junction.
Am J Surg Pathol 31: 1629-35
Smooth-muscle tumours with atypia and mitotic activity are designated leiomyosarcoma
, and such tumours are distinctly rare in the stomach.