Table of Contents
Definition / general | Epidemiology | Sites | Clinical features | Prognostic factors | Case reports | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Differential diagnosis | Board review style question #1 | Board review style answer #1Cite this page: Gonzalez RS. Leiomyosarcoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stomachleiomyosarcoma.html. Accessed January 22nd, 2021.
Definition / general
- Malignant smooth muscle sarcoma that arises from the muscularis propria of the stomach
- Accounts for 1% of all malignant tumors of the stomach
Epidemiology
- Mainly middle aged men (Kathmandu Univ Med J 2006;4:510)
Sites
- Upper part of the body or the fundus of the stomach (Kathmandu Univ Med J 2006;4:510)
Clinical features
- Patients typically present with peptic ulcer-like symptoms, though gastric outlet obstruction may occur (BMC Res Notes 2014;7:479)
- 5 year survival rate is approximately 50% (Histopathology 2013;63:194)
Prognostic factors
- Size of 5 cm or greater is a poor prognostic factor (Histopathology 2013;63:194)
Case reports
- 50 year old woman with hypertension and diabetes presented with a submucosal gastric mass (Case of the Week #438)
Microscopic (histologic) description
- Composed of spindle cells with elongated nuclei and eosinophilic fibrillary cytoplasm arranged in fascicles
- Prominent atypia with enlarged, hyperchromatic and pleomorphic nuclei is seen, with brisk mitotic activity and areas of necrosis (Odze and Goldblum: Surgical Pathology of the GI tract, Liver, Biliary tract, and Pancreas, 3rd ed., 2015).
Differential diagnosis
Board review style question #1
Which of the following is a poor prognostic indicator for this neoplasm?
A. Greater than 20 mitoses per 10 high power fields
B. Ki67 proliferative index above 50%
C. Size greater than 5 cm
D. Tumor necrosis
A. Greater than 20 mitoses per 10 high power fields
B. Ki67 proliferative index above 50%
C. Size greater than 5 cm
D. Tumor necrosis
Board review style answer #1