Staging and management of localized non-Hodgkin's lymphomas: variations among experts in radiation oncology

To examine the opinions of radiation oncology experts on the management of lymphomas with respect to staging procedures, treatment plan, radiation target volume, and dose prescription. Our aim was to identify the patterns of practice and areas of controversy that may need to be resolved and be amenable to prospective clinical trials.

Radiation oncology experts in lymphoma management were identified from academic centers in the United States, Europe, and Canada. A sample of individuals with a publication record and/or participation in the design and execution of lymphoma clinical trials (n = 33) were mailed a questionnaire of five case scenarios. The experts were asked to specify their approaches to staging investigations, treatment plan, radiation target volume, and dose prescription for each scenario. Radiation fields were indicated by the respondents on a schematic anatomy diagram on the questionnaire. The response rate to the survey was 82% (27/33).

Staging of lymphomas relied on the use of imaging, because computed tomography of the abdomen and pelvis was recommended in all cases, and computed tomography of the uninvolved thorax was advocated by 70% of respondents. A lymphangiogram and a gallium scan were suggested by, respectively, 26% and 25% of respondents. The overall treatment plan was uniform for the four cases of localized presentations of lymphoma. However, the details of chemotherapy and radiation target volume varied significantly. Variations were observed in recommendations regarding the number of courses of chemotherapy and the extent of radiotherapy. The survey documented significant differences in the recommended radiation therapy (RT) dose (30-50 Gy). The scenario of leptomeningeal relapse in diffuse large B-cell lymphoma documented the most diverse treatment recommendations. These varied from whole-brain radiation alone to systemic and intrathecal chemotherapy, radiation with craniospinal coverage, and high-dose chemotherapy with bone marrow transplantation.

This survey demonstrated a high degree of consensus regarding the overall management plan of localized lymphomas among the sampled expert radiation oncologists. However, the recommendations regarding the specifics of chemotherapy and RT remain variable. There is clearly no agreement on the most appropriate RT dose and volume. The large variation in the treatment of leptomeningeal relapse of diffuse large B-cell lymphoma suggests that the optimal treatment in this situation is poorly defined, and the clinical outcome with RT, as well as the rationale for decision making, should be examined in more detail.