Critical assessment of head and neck cancer with respect to staging has, on occasion, been disappointingly ineffective. We have attempted to correlate the incidence of measureable uptake of cobalt 57 tagged bleomycin by primary squamous cell carcinoma and metastatic cervical lymph nodes. Forty-six cases have been evaluated with respect to histopathological confirmation of the suspected metastatic disease. We have found that this diagnostic measure increases our acumen in staging of head and neck cancer. The relevance of the Co-Bleo scans as a diagnostic aid is reported in 46 cases. Malignant tumors greater than 2 cm in size appear to demonstrate active uptake of the imaging agent. Small tumor size and excess background radioactivity contribute to the false-negatives (17%). Inflammatory conditions or benign tumors of the salivary apparatus may result in minimal uptake, thus, a false-positive result (10%). An increase in the radioactivity of the Co-Bleo may enhance the benefits of this procedure in the search for an undiagnosed primary, as well as undiagnosed local or distant metastases.