Soft tissue sarcomas of the head and neck: An update*

Soft tissue is defined as mesenchymal, extraskeletal tissue excluding the reticuloendothelial, glial, and parenchymal organ-supporting tissue. Tumors arising from soft tissue are classified according to their postulated histologic origin, typically based on the adult tissue they most resemble. Although it has been speculated that most sarcomas arise from a primitive mesenchymal cell, this seems very unlikely when one considers that the vast majority of sarcomas are of a single phenotype and remain true to that phenotype throughout their natural history. Occasional sarcomas “dedifferentiate,” but true malignant mesechymomas—with their multiple phenotypes—are rare. Thus, it is highly likely that sarcomas arise from an abnormal event occurring in a cell of an already committed mesenchymal phenotype, even though such a cell may seem primitive and without visible differentiation when using currently available diagnostic techniques. Soft tissue sarcomas (STS) are uncommon tumors—it is estimated that approximately 7,800 adults will be affected by the disease during 1999. In the Memorial Sloan-Kettering Cancer Center (MSKCC) sarcoma database, only 0.05% (n 5 159) of 3,796 adult patients who underwent inpatient care for sarcomas had tumors involving the head and neck, but figures up to 11% have been reported. Apart from being rare, what also sets soft tissue sarcomas of the head and neck (STSHN) apart is the critical anatomy of the head and neck that limits the capability of the treating physician to attack them vigorously without causing unacceptable physiologic, functional, and cosmetic damage to the patient. This inability to deliver aggressive treatment may explain why these tumors have historically been associated with poor outcome. Another major confounding factor is the degree of disagreement among pathologists in the classification of STS. In addition, the pathologic diagnosis is not always straightforward, and tumors such as lymphoma, melanoma, and giant cell carcinoma are likely to be confused with STS. Benign processes such as fasciitis, neurofibromas, and lipomas can also mimic sarcomas, and because the vast majority of soft tissue tumors are benign, the clinician needs to have a definite plan to be able to strike a balance between mistreating malignant tumors and overtreating benign ones. Our knowledge of these tumors is restricted because they are rare, and the literature is replete with studies that have tried to compensate by analyzing cases registered over many decades, or cases pooled from more than one center, or by including pediatric and bone tumors that are known to behave differently. The pitfalls of conclusions that are drawn from such studies are obvious, and the purpose of this review is to collate currently available information and provide a concise update on the diagnosis and management of STSHN. From the Head and Neck Service, Memorial SloanKettering Cancer Center, 1275 York Ave, New York, NY. Address reprint requests to Ashok R. Shaha MD, FACS, Head and Neck Service, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10021. Copyright © 2001 by W.B. Saunders Company 0196-0709/01/2201-0001$35.00/0 doi:10.1053/AJOT.2001.20699