[Imaging and biopsy of soft tissue tumors]. / Bildgebung und Biopsie von Weichteiltumoren.

Soft tissue tumors represent a special challenge in interdisciplinary cooperation. Malignant tumors require a multimodal therapy concept so that patient treatment in a specialized tumor center is recommended. The task of the surgeon in close cooperation with the radiologist is the resection of the tumor in sano with the required safety margin. The aim of diagnostic imaging is to describe the primary expansion of the tumor size and a possible tumor infiltration of adjacent compartments. The most important diagnostic imaging for this purpose is magnetic resonance imaging (MRI), especially T1-weighted fat-suppressed gadolinium-enhanced sequences. Together with T2-weighted sequences a reliable differentiation between necrosis and vital tumor tissue is possible, which enables a targeted biopsy of vital tumor tissue. For the differentiation between benign and malignant soft tissue tumors and for determination of histological differentation a core needle biopsy, either computer tomography-guided or under sonographic control and increasingly more by MRI guidance, is currently the gold standard in most tumor centers. A representative biopsy from vital tumor tissue leads to the diagnosis with a very high degree of certainty.

[Soft tissue tumors : Epidemiology, classification and staging]. / Weichteiltumoren : Epidemiologie, Klassifikation und Stadieneinteilung.

Benign, intermediate and malignant soft tissue tumors can be differentiated histologically. Furthermore, the tumors can be subdivided according to their linear differentiation. In the new World Health Organization (WHO) classification of soft tissue tumors from 2013 changes have been made relating to the allocation of known entities, e. g. undifferentiated sarcomas have been formed into a new subgroup and are no longer assigned to the fibrohistiocytic tumors. The term malignant fibrous histiocytoma has been replaced by the undifferentiated sarcoma. Furthermore, two new subgroups were incorporated, the nerve sheath tumors and gastrointestinal stromal tumors. These were previously included in the tumor classification of other organ systems. These changes in the new classification are related to the rapid increase in knowledge of the genetics and the cell biology of soft tissue tumors. Malignant soft tissue tumors only represent 1% of all malignant tumors in adults. The largest subgroup of soft tissue tumors in adults is the adipocytic tumors. The liposarcoma, which belongs to this subgroup is one of the most common malignant soft tissue tumors in adults. In childhood malignant soft tissue tumors represent 15% of malignant tumors and rhabdomyosarcoma is the most common malignant soft tissue tumor.