Long-term follow-up of general immune competence in breast cancer. II. Sequential pre- and post-treatment levels: a 10 year study.

Pre-treatment and sequential post-treatment (at 3 months, 6 months, 1, 2, 3, 4 and 5 years) examination of general immune competence was performed in 185 consecutive breast cancer patients. The patients were followed for 5 to 11 years to monitor the dynamic relationship between host immunity and cancer and to examine the effect of the treatment method. The tests of immune competence used were immunoglobulins IgG, IgA, IgM, leucocyte counts, percentage and total lymphocyte counts and Mantoux and DNCB skin hypersensitivity tests. Serum IgG and IgA showed no change relating to treatment method in recurrence-free patients; but IgG levels were higher when recurrent disease was imminent or established; IgM diminished (P less than 0.001) after treatment and this continued at 5 years in all patient groups. Simple lymphocyte counts showed the most interesting changes. They remained depressed for as long as 60 months following radiotherapy (P less than 0.01). After treatment by surgery, lymphocyte counts rose in patients without recurrence, but fell when systemic recurrence was imminent or established. This effect was not seen in patients with local recurrence only. There was no change in immune competence immediately before recurrence sufficient to be of clinical usefulness, but a low pre-treatment lymphocyte count with a steady rise after surgery carried a good prognosis. Similarly a high initial lymphocyte count with a fall after surgery was indicative of recurrence. Universal and prolonged depression of lymphocyte counts following radiotherapy was confirmed, and the effect was additive to that of tumour load in recurrent disease. Because of the large number of statistical calculations carried out, some of the apparently significant findings may be due to chance. However, the general trends emerging suggest that similar long-term studies, using the more sophisticated measures of lymphocyte function now available, might be rewarding.