A collaborative study of the humoral and cellular immune status of patients with carcinoma of the Head and Neck (H&N) was conducted at the West Virginia University (WVU) hospital. In addition, blind-coded serum panels were supplied on H&N cancer patients being treated at the National Cancer Institute (NCI). Serum protein analysis of the WVU study groups revealed that at the pretreatment sampling, the alpha-1 acid glycoprotein (AGP), total complement, and IgA levels were significantly elevated. The AGP levels and total complement levels declined to normal levels in the post-treatment period, whereas the IgA levels remained elevated throughout the entire observation period. Levels of serum immune complexes (SIC) were measured in both the WVU and NCI H&N cancer populations using the polyethylene glycol (PEG) precipitation method. In both survey populations all cancer groups had significantly elevated levels of SIC when compared to any of the control populations. The SIC levels never returned to comparative normal values even in cases after successful treatment. A subpopulation of the WVU-H&N cancer study group underwent a short course of intravenous hyperalimentation prior to their treatment regimen. These patients demonstrated a transient decrease in their SIC levels as well as a concomitant increase in their in vitro cell-mediated immune (CMI) correlates. The analysis of in vitro CMI correlates of the WVU study group using both polyclonal mitogens and specific antigens demonstrated a significant depression in these parameters pretreatment and post-treatment. In addition, it was observed that the time course for elevation of selected serum proteins (i.e., IgA and SIC) correlated with concomitant drops in CMI activity. Investigations were also conducted into the effects of immune complex-rich serum fractions upon selected in vitro CMI correlates. Significant blockage of a normal donor leukocyte migration-inhibition assay was demonstrated. Also, a similar inhibition of the ability of normal human lymphocytes to form high affinity rosettes was accomplished with serum from H&N cancer patients.