HISTOLOGIC-FINDINGS IN PATIENTS WITH HEAD AND NECK SQUAMOUS-CELL CARCINOMA RECEIVING PERILYMPHATIC NATURAL CYTOKINE MIXTURE (IRX-2) PRIOR TO SURGERY

Objectives.-To induce tumor regression with immunotherapy and to chara cterize the histology. Setting.-National Institute of Cancerology, Mex ico City, Mexico. Patients.-Thirteen patients with advanced squamous c ell carcinoma of the head and neck region. Intervention.-A 21-day cycl e of preoperative immunotherapy, including a single intravenous infusi on of low-dose cyclophosphamide (300 mg/M-2), 10 daily perilymphatic i njections of a natural cytokine mixture (approximately 150 units inter leukin-2 equivalence by enzyme-linked immunosorbent assay), daily oral indomethacin, and daily oral zinc with multivitamins. Outcome Measure s.-Pretreatment biopsies were performed to confirm the diagnosis and t o characterize the lesion by standard pathologic criteria, including t he degree of tumor-associated lymphocytes. Clinical responses were ass essed at surgery, and the specimen was analyzed with respect to change s in tumor morphology and lymphoid and inflammatory infiltration (T an d B lymphocytes, plasma cells, macrophages, granulocytes, and giant ce lls). The presurgical and postsurgical characteristics were ascribed p ercentages based on a representative section. Results.-Prior to treatm ent, on average the biopsies demonstrated 77% solid tumor with 14% str oma and 9% sparse infiltration of lymphocytes. After treatment, one pa tient had a complete clinical response and showed only residual inflam matory cells and fibrosis. One patient had no clinical or histologic r esponse. Of the remaining 11 patients, 4 had partial, 6 had minor, and 1 had no response. Tumors were reduced an average of 41% (16% solid a nd 25% fragmented) and lymphoid infiltration increased to 45% without change in residual stroma. Conclusions.-The pathologic changes viewed in the context of the clinical findings,indicate that this immunothera py protocol induces immune regression of the tumor, mediated predomina ntly by T and B lymphocytes, and thus elicits a tumor-specific immune reaction.