Postoperative Radiation Therapy and Adjuvant Chemoimmunotherapy in Breast Cancer Aspects of Timing and Immune Competence

Abstract

The effects of radiation therapy and adjuvant chemoimmuno-therapy on the immune competence of patients with breast cancer were investigated. The tests performed included intradermal tuberculin tests, T- and B-lymphocyte counts, and lymphocyte blast transformation tests; phytohemagglutinin (PHA), concanavalin A (ConA) and pokeweed mitogen (PWM) were used as mitogens. Enhancement in lymphocyte proliferative response to mitogenic stimulation by PHA and PWM was seen in patients after 3 courses of chemotherapy + levamisole, whereas irradiation given after chemotherapy caused long-lasting depression in response to PHA (p=0.039) and PWM (not significant). T-lymphocyte counts were also lower after irradiation than after chemoimmunotherapy (p=0.007). Clinically, the 16 patients treated with radiation therapy after chemotherapy exhibited a higher recurrence rate than the 24 patients treated first by irradiation. Enhanced reactivity to tuberculin tests occurred generally in patients receiving a planned treatment including irradiation, chemotherapy (5-fluorouracil, doxorubicin, cyclophosphamide) and levamisole. Enhancement of reactivity was seen more often in patients who had not relapsed.

Key Words:

• Breast neoplasms
• operable cancer
• radiation therapy
• chemotherapy
• levamisole
• immune competence