Soft tissue Tumors of the head and neck

Soft tissue tumors of the head and neck are neoplasms that arise from the tissues of the facial and cervical region and do not originate in the osteocartilaginous skeleton, nor in the trachea of the esophagus, the larynx, the thyroid, the parathyroids and the salivary glands. They represent 10% of all soft tissue tumors. Other exclusions are skin tumors, central nervous system tumors, lymph node metastases. Including the derivatives of the vascular endothelium and excluding congenital processes such as lymphangioma and teratoma.

100 benign and 50 malignant entities have been described, with very different behaviors. Its frequency is estimated at 2/100 000 inhabitants/year, they are more frequent in children (6.5% in children and 1% in adults. The benign/malignant ratio varies according to the series from 2/1 to 100/1.The most common form of presentation is that of a mass that produces compressive symptoms in contiguous neurovascular structures. Occasionally, lesions can be located on the skin, such as angiosarcomas and dermatofibrosarcoma protuberans. Benign lesions have a slow and gradual growth, although in other benign lesions such as nodular fasciitis this is rapid and infiltrative. Despite this exception, a well-defined surface mass, less than 5 cm., of slow growth presents a high possibility of being benign; While if it is deep, it grows quickly, has a peritumoral infiltrative appearance and a size greater than 5 cm. it is more likely to be malignant.

Benign soft tissue tumors of the large neck may have compressive symptoms that depend on the location of the tumor and contiguous structures. In general, the most striking are the neurological symptoms (paresthesias, paralysis, neuralgia), which may coincide with a tumor originating from the peripheral nerve. In this case it is not possible to move the mass in the direction of the axis of the nerve, although it is possible in its perpendicular axis. Rarely, paralysis is caused by compression outside the cervical region, as described in cervical lipomatosis, which infiltrates the mediastinum and produces bilateral paralysis of the recurrent, Other times the predominance of symptoms is vascular (larte mass, hypertensive crises, hemorrhagic diathesis) seems to indicate a vascular tumor. In the case of settling on the carotid axis, it is only possible to move it laterally.

The same neurovascular symptomatology can be observed in malignant tumors, although by infiltative mechanism. In advanced lesions or high degree of malignancy, inflammatory reactions, hemorrhages, necrosis and ulcerations that presume their character are also produced.

In case of suspicion, an FNA is required, which can guide but is not always the definitive diagnosis. It has the advantage of avoiding the dissemination that would cause the incisional biopsy, which should only be considered in case of inoperability of the tumor or in the same surgical act, proceeding then to its complete removal.

Excisional biopsy is recommended in benign lesions, well encapsulated, provided that their size allows it. It is not the appropriate procedure for sarcomas, especially if they are larger than 3 cm., although they have a good plane of detachment.

Once the tissue diagnosis has been established, the extent of the tumor must be known, as well as the secondary involvement of the great vessels and the upper respiratory and digestive tract, using imaging techniques such as CT and MRI; As well as investigate the possibility of metastasis in other organs (lungs, liver and bones).

Type and approximate frequency of cervicofacial soft tissue tumors.

Tissue Tumor Benigno Malignant tumor
Adipose Lipoma (27%) Liposarcoma (8%)
Fibrous Connective Fibroma (2%)
Fascitis nodular (15%)
Fibrosarcoma (10%)
Dermatofibrosarcoma P.
Nerves Neurofibroma(7%)
Neurogenic sarcoma(1%)
Malignant schwanoma (10%)
Vascular Hemangioma (11%)
Smooth muscle Leiomyoma Leiomiosarcoma
Striated muscle Rabdomioma Rhabdomyosarcoma
Synovial Giant cell tumor Synovial sarcoma