Thymectomy in ulcerative colitis: a report of cases over a 13 year period.

Seventy eight patients with ulcerative colitis were treated by thymectomy combined with conventional therapy. An interim analysis was made after a median follow-up of 40 months in the thymectomized group and after 25 months in 173 from a non-thymectomized group. The percentage of remission periods in the thymectomized group was significantly higher than that in the non-thymectomized group as estimated by the "patient-month" method. Histological examination of the excised thymus revealed hyperplasia of the thymic epithelial cells and/or the formation of lymphoid follicles. Anticolon antibody activity of the serum from the thymectomized patients decreased gradually and disappeared in 5 years or more. "Thymectomy via the suprasternal notch with parasternal incision" which was applied in this study, is simple and not invasive. Therefore, it is recommended that thymectomy should be considered as one of the treatment for patients who are resistant to conventional therapy.