A rare case of solitary fibrous pelvic tumor

Non-organ retroperitoneal tumors are a heterogeneous group of malignant neoplasms that develop from different types of connective tissue, which in turn determines the variety of histological forms. More than 3,000 new cases of soft tissue sarcomas are registered an‑ nually in Russia, which is 1 % of all malignant neoplasms. In 2021, 3150 new cases of malignant neoplasms of connective and other soft tissues were detected for the first time. Retroperitoneal sarcomas account for 10–15 % of all types of soft tissue sarcomas. Diagnosis and treatment of non‑organ retroperitoneal tumors is an extremely difficult task. Non‑organ retroperitoneal tumors of mesenchymal origin are characterized by extremely rapid and aggressive growth. The prognosis of the disease is determined by the variant of the histological structure, the primary localization of the tumor, as well as timely and adequate treatment. Considering that non‑organ retroperitoneal tumors can metastasize to other organs in more than 30 % of cases, they are often detected at an advanced stage. Existing methods of radiation diagnostics and other research methods conducted within the framework of the examination standard, which can generally characterize the primary tumor of the retroperitoneal space, but in more than 60 % of cases give false positive information about the degree of tumor germination into neighboring organs and structures, especially into the main vessels. For this pathology, the main method of treatment is surgical. The long‑term results of surgical treatment and the expediency of palliative removal are currently insufficiently studied. Therefore, it is necessary to improve the methods of diagnosis and surgical treatment of non‑organ malignant tumors of the retroperitoneal space. Correct preoperative assessment of the prevalence and histological structure of the tumor allows you to choose an adequate amount of surgical intervention. This article presents a clinical observation of successful surgical treatment of a patient with solitary fibrous pelvic tumor.

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