Retroviral p15E-related serum factors and recurrence of head and neck cancer.

Surgical removal of head and neck squamous cell carcinoma (HNSCC) restores the defective monocyte polarization found in patients with HNSCC. Since HNSCC contain p15E-like low molecular weight factors < 25 kD (LMWF) capable of suppressing N-formyl-methionyl-leucylphenylalanine (fMLP)-induced monocyte polarization, it is likely that HNSCC removal eradicates the production site of p15E-like factors. This report describes a prospective follow-up study on the levels of bioactive p15E-like serum factors for a period of 2 years in nine patients with HNSCC who had no recurrence and 11 patients with HNSCC who showed residual or recurrent disease after treatment. In the group of patients without recurrent disease p15E-like bioactivity gradually decreased and eventually became negative. In patients with recurrent/residual disease p15E-like bioactivity remained high or even became positive before or at the time of diagnosing tumour recurrence. This study strongly supports the concept that HNSCC tumours are the production site of p15E-like immuno-suppressive factors and indicates that serum p15E-like factors may be used for future studies on early serum markers for recurrent/residual disease developing in the first year after treatment.