Effect of immunostimulating therapy on the immunocompetent system in breast carcinoma

The authors studied 68 patients suffering from breast cancer, with or without lymph node metastasis, who underwent surgery and antitumour therapy (CMF). Twenty-three patients were treated using CMF and 1.5 mg/kg of thymostimulin, 24 with CMF and 1 mg/kg of thymostimulin and lastly, 21 subjects received anti-tumour therapy with CMF alone. Thymostimulin was administered every day for a week prior to surgery; subsequently, it was administered on alternate days for a week and then twice a week for 3 months. The blastogenesis of immunocompetent cells was evaluated. During thymostimulin treatment a higher rate of 3HTdR captation (p < 0.005) by cells stimulated with ConA + IL-2 was observed; these levels tended to increase after 3 weeks and reached statistically significant levels after 3 months of treatment; no significant changes were observed in those patients treated with CMF alone. In addition, the cytotoxic activity of monocytes and NK cells against K-562 cells and against short-lasting cell lines derived from breast carcinoma was also studied. It was observed that this activity increased significantly (p < 0.002) following thymostimulin treatment; this increase was greater in subjects treated with 1.5 mg/kg compared to those treated with 1 mg/kg, but the difference was not statistically significant. The study also evaluated the presence of IL-2 receptors (Tac): thymostimulin treatment for 3 months led to the appearance of receptors, although in restricted numbers, on non-stimulated cells. After IL-2 stimulation, the percentage of cells with Tac receptors increased significantly (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)