Purified protein derivative (PPD) tuberculin as a biological response modifier: I. Suppression of tumor markers by intravenous administration of PPD.

Forty-two patients with neoplastic diseases received intravenous administration of PPD (PPD-V), and tumor markers were monitored between January, 1986 and February, 1987. Tumor markers such as CEA, AFP, SCC, CA125, lAP and polyamines decreased significantly following the PPD-V therapy. In some cases, PPD-V therapy also reduced the progression of clinical manifestation of the disease. We could not detect serum IL-2 or TNF activity. IL-2 production and sensitivity of lymphocytes were also undetectable. Intravenous administration of PPD was concluded to be effective as an adjuvant therapy against human neoplastic disease. A reduction of tumor markers was observed in 19 of the 26 assessable patients (73%). We discussed the mechanism of suppression of tumor markers by PPD-V therapy.