Unknown primary squamous cell carcinoma metastatic to the neck.

We analyzed retrospectively 157 cases of metastatic neck squamous cell carcinoma from unknown primary sites, treated with surgery, radiotherapy, excisional biopsy, and combined modalities. Median follow-up was 74 months, and overall actuarial survival was 55% at 5 years. The surgery-treated group, despite a higher rate of manifesting primary tumors, had significantly better survival at 5 years compared with those receiving radiation therapy, of whom 23% had residual disease after treatment. Primary tumors were discovered during follow-up in 16% overall. Different treatments yielded comparable results in lower-staged neck disease (NX, N1, N2a), while surgery appeared more effective in controlling advanced disease (N2b, N3a). Factors that affected survival include neck stage, connective tissue invasion, and presence of recurrent or residual disease after treatment.