CENTRAL LYMPHATIC IRRADIATION FOR STAGE-III NODULAR MALIGNANT-LYMPHOMA - LONG-TERM RESULTS

Purpose: To report the long-term results of central lymphatic irradiation for stage III nodular malignant lymphoma. Patients and Methods: Between 1969 and 1985, 34 patients (26 with nodular poorly differentiated lymphoma, four with nodular mixed lymphocytic/histiocytic lymphoma, and four with nodular histiocytic lymphoma) were treated with central lymphatic irradiation. Median age of the group was 51 years (range, 30 to 73). There were 15 men and 19 women. Staging work-up included a physical examination and bone marrow biopsy in all patients. Seventy-four percent had a lymphangiogram (LAG) and 44% a laparotomy (LAP). Eighty-two percent had either a LAP or a LAG. Thirty-two patients were Ann Arbor stage IIIA and two were stage IIIB. All patients received lymphatic irradiation that encompassed cervical, supraclavicular, axillary, mediastinal, paraaortic, mesenteric, pelvic, and femoral lymphatics to total doses ranging from 20 to 30 Gy in 1.0- to 1.8-Gy fractions. Waldeyer's ring was initially treated in 17 patients. Follow-up information is available on all 34 patients. Median follow-up is 9 years, 8 months (range, 15 to 244 months). Results: Life-table actuarial overall, disease- free, and cause-specific survival rates at 15 years are 28%, 40%, and 46%, respectively. Only one relapse was observed after 9 years. Disease-free survival was significantly improved in patients with five or fewer sites of involvement (P = .02). Age, sex, B symptoms, histology, and technique of irradiation were not prognostically significant. Salvage therapy, including further irradiation and/or chemotherapy, was delivered to 20 patients. Ten percent of these patients remain alive without evidence of disease. Toxicity data were available for the patients treated at the Medical College of Wisconsin (MCW). Radiation Therapy Oncology Group (RTOG) acute hematologic, gastrointestinal, and salivary toxicity scores were ≤ 2 in 83% of patients. Late toxicity scores were ≤ 2 in 96%. Persistent xerostomia was noted in 23% of patients who received initial treatment to Waldeyer's ring. Conclusion: These results suggest that initial comprehensive central lymphatic irradiation may be the preferred approach to achieve a durable relapse-free interval for this group of patients.