Malignant melanoma of the head and neck. Clinical and immunological considerations.

Prolonged exposure to sun for long periods during most of the year has led to an increase in the frequency of malignant melanoma in Israel, especially for head and neck (H&N) melanoma. H & N melanoma is found in males more than in females and diagnosed when already locally advanced. The disease-free interval between treatment of the primary lesion and recurrence of the disease correlated with the patient's age and the depth of invasion according to Breslow. A higher recurrence rate correlated with male gender, location in the scalp, and the stage of the disease. Metastatic disease involved the lungs, liver, and brain and responded poorly to systemic therapy. Improved survival was related to female gender, early stage of the disease, low Breslow thickness, and location of the primary lesion elsewhere than the scalp. Immunologically, we found that the titers of antimelanoma antibodies in patients with metastatic disease originating in the area of the head and neck were higher than the titer in disease-free H & N melanoma patients (p = 0.05). Moreover, patients with metastatic H & N melanoma had a higher titer of antityrosinase antibodies compared with healthy subjects. These two types of antibodies might be used as markers for disease progression in H & N melanoma. The more aggressive character of H & N melanoma was not reflected by different titers of antimelanoma antibodies nor by antityrosinase antibodies in patients with H & N versus non-H & N melanoma.

EBV genome and immunoglobulin gene rearrangement in the differential diagnosis of nasopharyngeal carcinoma and lymphoma.

Head and neck tumors include nasopharyngeal carcinoma (NPC) and lymphoma. The differential diagnosis of these tumors is based on histology, immunocytochemical staining, and EBV serology. In rare cases it might be difficult to distinguish between NPC and lymphoma in HE section or biopsies. DNA hybridization with cloned EBV and human immunoglobulin gene fragments allows the detection of EBV-related sequences and immunoglobulin gene rearrangements. The presence of EBV genome supports the diagnosis of NPC or EBV related BL, while rearrangement of immunoglobulin genes points to B-cell lymphoma. The diagnosis in 11 patients suspected of head and neck tumors was carried out by hybridization of DNA extracted from the tumors and assayed with cloned EBV and IgHCJ DNA probes. One patient proved to have EBV-associated BL based on positive hybridization with EBV probes and immunoglobulin rearrangement, presenting a unique hybridization with cloned EBV DNA BamHI W fragment, with bands of 3.2 and 3.9 kb. BL was confirmed in this patient by demonstration of c-myc rearrangement. A second patient was negative in hybridization with EBV, and positive for immunoglobulin rearrangement, and therefore was diagnosed as having B-cell lymphoma. In seven patients NPC was confirmed by hybridization with EBV-DNA probes. In two patients, both NPC and B-cell lymphomas were excluded.