Gastric Schwannoma as an Important and Infrequent Differential Diagnosis of Gastric Mesenchymal Tumours: A Case Report and Review of Literature.

The spectrum for gastrointestinal tract mesenchymal tumours includes leiomyomas, leiomyosarcomas, gastrointestinal stromal tumours (GISTs) and schwannomas. Schwannomas (also known as neuroma, neurilemmomas or neurinomas of Verocay) are well-known slow-growing, benign neoplasms that originate from nerve plexuses within a Schwann cell sheath. They can arise anywhere along the course of the peripheral nerve and are frequently reported around the head and neck, brachial plexus and along the gastrointestinal tract. Usually, these tumours are detected as solitary; however, they can occur at multiple sites around the body. Schwannomatosis (multiple schwannomas) is usually associated with neurofibromatosis type 2; the pathogenesis is triggered by mutations of the neurofibromatosis 2 tumour suppressor gene resulting in a loss of its function. Solitary gastric schwannomas are rare lesions that arise from the nerve plexus of the gastric wall. Frequently they are detected incidentally or may present with nonspecific abdominal pain or bleeding. This paper reports the case of a 79-year-old patient diagnosed with gastric schwannoma after presenting with abdominal pain. Gastric schwannomas should be taken into consideration while making a differential diagnosis of lesions that are gastric mesenchymal tumours, which span a broad spectrum. Gastric schwannomas are typically benign, considerably less common than gastric GISTs, and have an excellent prognosis following excision.