Adipocytic, Vascular and Skeletal Muscle Tumors A Practical Diagnostic Approach

Regarding the interpretation of biopsies performed on soft tissue tumors, an old sentence of the philosopher Henry David Thoureau (1817–1862), “The question is not what you look at, but what you see,” maintains during the years its value and fits perfectly with the difficulties encountered by pathologists in their daily clinical practice, in the diagnosis of these tumors. When sitting alone at the microscope looking at the hematoxylin and eosin (H&E)-stained sections of a soft tissue tumor, in such moments, it is not the complex chromosomal translocations we see, or the molecular changes underlying tumor insurgence and progression. It is the morphol- ogy of cells and their architecture, it are the characteristics of the stroma and of the vessels of the tumor, it is the tale of human pathology, the tradition of H&E that, probably, will never change. This will be the most complicated task of this book: in times in which molecular genetic approaches are an extremely relevant tool for the classification and therapy of soft tissue tumors, our aim is to underline the most important morphological and immunohistochemical data that should guide all sur- gical pathologists in the differential diagnosis of this family of tumors. To this end, in this book, we decided to focus on the use of drawings, utilized as vehicles for communicating the experiences of expert pathologists of previous generations to current surgical pathologists. Our idea is that a schematic representation of each tumor entity, and of all its variants, will help pathologists in training to build up their diagnostic skills, eventually reaching a correct diagnosis. Our goal is to provide bet- ter and faster training in the field of soft tissue tumors for resident pathologists, whose skill can mean the difference between life and death for patients. In addition, the most important molecular testing appropriate for each tumor entity will be reported, in an attempt to demonstrate the practical application of molecular analy- sis in the daily practice of surgical pathologists dealing with soft tissue tumors.