Schwannoma gástrico: descripción de un caso con presencia de células gigantes multinucleadas tipo osteoclásticas

We describe a gastric schwannoma in a 64 year-old man which clinical and radiologically simulated a gastrointestinal stromal tumor. A partial gastrectomy was performed showing an intramuscular wall tumour measuring 4 cm in diameter with unaffected mucosa. Microscopically the tumour presented a spindle cell pattern showing cuffing of lymphoid aggregates in the periphery and interstitium. Scattered abortive Verocay-like formations were present. In addition, some multinucleated osteoclastic-type cells were evenly dispersed. The spindle cells showed focal nuclear atypia. No mitotic figures were recorded. Immunohistochemically, the fusiform cells were strongly and diffusely positive for S-100 and GFAP, whereas stains for CD34, CD117 and DOG1 were negative. Multinucleated cells were CD68 positive. We briefly discuss the differential diagnosis.