The overwhelming majority of human tumors showing melanocytic differentiation occur in the skin and represent benign melanocytic nevi, their variants, and malignant melanomas. However, a small percentage of tumors showing…
Benign extraosseous cartilaginous lesions are uncommon and usually present as tumorlike masses. In the past, the term soft part chondroma or extraskeletal chondroma was used arbitrarily for small, well-defined, solitary…
The term hemangioma has been used broadly in the past to describe any benign, nonreactive vascular process with an increase in normal or abnormal-appearing vessels or simply abnormally configured vessels….
Liposarcoma, accounting for 15% to 25% of all sarcomas, is the most common sarcoma of adults. There are several subtypes, which are histologically, biologically, and cytogenetically distinct from one another…
The lymphatics are an extensive unidirectional system of blunt-ending vessels that regulate normal tissue pressure by retrieving excess fluid from the interstitium, transporting it to regional lymph nodes, and returning…
This chapter discusses a heterogeneous group of benign tumors or pseudotumors, many of which are characterized by abundant myxoid stroma (intramuscular myxoma, juxta-articular myxoma, cutaneous myxoma, ganglion). Evidence indicates that…
The synovial membrane forms the lining of joints, tendons, and bursae. In addition, its cells synthesize hyaluronate, a major component of synovial fluid, and facilitate the exchange of substances between…
The significance and multiple functions of fat are not always fully appreciated. Fat serves not only as one of the principal and most readily available sources of energy in the…
Angiosarcoma Angiosarcomas are malignant tumors that recapitulate many of the functional and morphologic features of normal endothelium. They vary from highly differentiated tumors resembling a hemangioma to anaplastic lesions difficult…
To a large extent, the distribution of benign smooth muscle tumors parallels the distribution of smooth muscle tissue in the body. The tumors tend to be relatively common in the…
