Gastric wall mass

Clinical history: A 53-year-old lady presented with 3-month history of dysphagia. A CT scan of her thorax revealed a submucosal mass at the gastro-oesophageal junction. Endoscopic ultrasound-guided fine needle aspirate obtained the following smear.

Cytologic findings

Three differentials to consider: GIST, Smooth muscle tumour (Leiomyoma), Schwannoma

Similarities include:

Fascicular arrangement
Spindle cells
Uniform nuclei

	GIST	Leiomyoma	Schwannoma
Cellularity	Intermediate to high	Low to intermediate	Low to intermediate
Background	Clean, occasional naked nuclei	Clean	Lymphoid-rich, especially in the GIT
Nuclear atypia	Minimal	Minimal	Focal to minimal (ancient change)
Nucleus	Elongated with blunt ends	Elongated with blunt ends	Elongated with pointed ends
Cytoplasm	Scant, fibrillary	Moderate amounts	Scant, fibrillary

Immunohistochemistry

Diagnosis

Case writer: Dr Noel Chia

	GIST	Leiomyoma	Schwannoma
CD117 (C-Kit)	+	-	-
DOG1	+	-	-
CD34	+	-	-
SMA, desmin	-	+	-
S100	-	-	+

EUS-FNA 2

Gastric wall mass