Gastrointestinal stromal tumors are a group of rare malignant neoplasms of the gastrointestinal tract of mesenchymal origin. Clinical manifestations depend on the localization of neoplasia. A sensation of rapid saturation, pain, bloating, bleeding and the appearance of intestinal obstruction are possible. In the later stages, weight loss, fever, anemia, hyperthermia, and organ dysfunction, affected by distant metastases, are revealed. Diagnosis is made on the basis of complaints, objective examination data, CT, ultrasound, endoscopic examination and biopsy results.
Until the 1980s, specialists believed that tumors of this group originated from smooth muscle tissue and treated such tumors as leiomyosarcomas, leiomyomas and leiomyoblastomas. After introduction into clinical practice of immunohistochemical techniques and electron microscopy, it was established that cells of gastrointestinal stromal tumors originate from interstitial cells of the Cajal, which represent a link between the intramural nodes of the peripheral nervous system and smooth muscle cells of the hollow organs of the gastrointestinal tract. One of the main functions of such cells is the coordination of peristalsis of the wall of the esophagus, stomach and intestines.
Macroscopically gastrointestinal stromal tumors are loose soft knots of pinkish, gray or light brown color with mucosal areas. The diameter of the nodes can vary from 1 to 35 cm. During growth, such tumors can merge, forming conglomerates or cystic structures. In the center of large neoplasias, necrosis areas are usually found, cystic cavities with hemorrhages are seen in the tissue of the neoplasms.
The main method of treatment GISO is surgical intervention. The volume of the operation is determined depending on the localization and prevalence of neoplasia. The standard is a radical resection of pathological foci along with 1-2 cm of surrounding healthy tissues. The removed gastrointestinal stromal tumor is sent for an urgent microscopic examination, when the malignant cells are detected along the incision line, the lesion is excised.
Because of the rare lymphogenous metastasis, lymphadenectomy is not produced (except for gastrointestinal stromal tumors of the rectum, which in 25-30% of cases are metastasized into the lymph nodes). With single metastases, the liver performs radiofrequency ablation or the surgical removal of a secondary tumor.