Soft tissue tumors represent a heterogeneous group of lesions which include benign and malignant (sarcomas) mesenchymal proliferations. Sarcomas are rare and represent a real challenge in terms of diagnosis and therapy for the multidisciplinary medical team. The pathologist has to establish the correct diagnosis by answering several questions: is the lesion benign or malignant? if malignant, is it a sarcoma? and what type of sarcoma is it? He has to inform the clinician regarding the potential presence of prognostic factors. Careful evaluations of surgical margins of the resection specimen or of tumor response to neoadjuvant chemotherapy are additional aspects of the pathologic report. Optimal management of the patient depends on a close collaboration between pathologists, surgeons, radiologists, oncologist and radiotherapists.