Analysis of failures after whole abdominal irradiation in gastrointestinallymphomas - Is prophylactic irradiation of inguinal lymph nodes required?

Background: To evaluate failures and to investigate the need for prophylact ic inclusion of the inguinal lymph nodes in case of whole abdominal irradia tion in gastrointestinal lymphoma. Patients and Method: In October 1992 a prospective study on primary gastroi ntestinal lymphoma was initiated to evaluate management strategies. Treatme nt consisted either of conservative management comprehending radiotherapy /- chemotherapy or radio-/chemotherapy sequential to primary surgery, depen ding on the physician's decision. Until November 1996, 382 patients were en rolled. Out of them we analyzed 92 patients who received a whole abdominal irradiation, in 21 cases with prophylactic inclusion, in 71 cases without i nclusion of the inguinal lymph nodes. Results: After a median follow-up time of 36 months in 92 patients with who le abdominal irradiation 9 patients developed relapse of gastrointestinal l ymphoma (8 local failures, 1 distant failure). In these cases the analysis of radiation therapy shows low tumor doses or small field sizes. No signifi cant difference in the relapse rates is shown between the 21 patients with inclusion of the inguinal lymph nodes in the abdominal radiation fields (3 recurrences congruent to 14,3%) and the 71 patients without enclosure of th e inguinal lymph nodes (6 recurrences congruent to 8,5%). Conclusion: General prophylactic enclosure of the inguinal lymph nodes in t he case of whole abdominal irradiation in gastrointestinal lymphoma seems t o be unnecessary.