Hodgkin's disease: the right dose

Changing role and decreasing size: current trends in radiotherapy for Hodgkin's disease

Radiotherapy, the first cancer treatment modality that offered cure, is still considered to be the most effective "single agent" in treating Hodgkin's disease (HD). Yet, the role of radiotherapy in HD has changed dramatically with the advent of effective combination chemotherapy and the rising concern of long-term complications associated with successful treatment of HD. The new principles of integrating radiotherapy into a combined-modality regimen for HD at different prognostic stages are reviewed here, along with the effect of this new role on radiation field size and design.

Combined modality therapy for early Hodgkin's disease: heterogeneity in Australasian clinical practice

Two case studies of locally extensive clinical stage IIA Hodgkin's disease (HD) were presented to radiation oncologists at a meeting of the Australasian Radiation Oncology Lymphoma Group, and subsequently to non-attending members who were asked to indicate their recommended treatment. This paper discusses the 25 responses which were notable by considerable heterogeneity in philosophy and detail. There is clearly no consensus among Australasian radiation oncologists at present, although combined modality therapy (CMT) with Adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by low-medium-dose involved field radiotherapy (25-36 Gy) was the most popular response. The literature on radiation dose and chemotherapy in CMT for HD is then reviewed. It seems very likely that low doses in the range of 25-30 Gy (at 1.5-2.0 Gy per fraction) are sufficient. The ABVD should be considered as the 'standard' regimen at present, although the optimal sequencing with radiation and number of cycles remain unknown. The heterogeneity of responses to management of the case studies raises questions about ongoing education processes in radiation and medical oncology. Hypothetical case management review may complement currently proposed methods of assessing continuing medical education.

Hodgkin's disease

This synthesis of the literature on radiotherapy for Hodgkin's Disease is based on 104 scientific articles, including 2 meta-analyses, 22 randomized studies, 5 prospective studies, and 58 retrospective studies. These studies involve 38,362 patients. The literature review clearly shows that radiotherapy is a cornerstone of treatment for localized Hodgkin's disease. At early stages, long-term survival is 80% to 90% when treatment is tailored to known prognostic factors. There is a tendency toward increased use of chemotherapy as additional treatment, however no evidence shows that it increases survival. To further improve survival following radiotherapy an attempt is being made to reduce long-term toxicity by better defining the patient groups who require lower radiation volumes, and delivering a dose that is as low as possible to avoid secondary solid tumors or delayed cardiopulmonary or gastrointestinal effects, while not jeopardizing therapeutic results. In advanced disease, radiotherapy may be needed as a complement to chemotherapy to effectively control bulky disease. For recurrent disease, radiotherapy may be considered as relapse treatment or additional therapy in conjunction with high-dose chemotherapy.

The importance of staging laparotomy in pediatric Hodgkin's disease

The findings of 247 pediatric patients who presented with supradiaphragmatic Hodgkin's disease and underwent staging laparotomies between April 1969 and December 1991 were reviewed to assess the importance of the staging laparotomy in pediatric Hodgkin's disease. A change in stage occurred in 25% of the cases reviewed. Fifty of the 202 (25%) clinical stage (CS) I or II patients were upstaged to pathological stage (PS) III or IV, and 12 of the 45 (27%) clinical stage III or IV patients were downstaged to pathological stage I or II. Possible risk factors for positive surgical staging, including gender, age, presence or absence of B symptoms, extent of involvement above the diaphragm, and histological type, were used to define subgroups of patients. Three statistically significant subgroups of patients with less than a 10% chance of restaging were identified. These groups included CS I and II patients with lymphocyte-predominant histology, CS I females, and CS III and IV females with nonlymphocyte predominant histology. These subgroups represent 24% of the cohort. Because CS is an accurate predictor of PS in these groups, treatment could be based solely on CS. The impact of radiographic imaging techniques on correctly predicting pathological stage was assessed. The rates of restaging for individuals with lymphangiography or computed axial tomography were not statistically different from those of patients without these radiographic studies. Therefore, abdominal imaging is not a substitute for surgical staging. No mortality and 2.8% morbidity occurred from staging laparotomy. Postsplenectomy sepsis and small bowel obstruction were the most common complications. Ninety-six percent of upstaged patients had splenic involvement, and 54% had positive nodal involvement.(ABSTRACT TRUNCATED AT 250 WORDS)

Variation in mantle technique: implications for establishing priorities for quality assurance in clinical trials

74 European and American radiotherapists responded to a questionnaire investigating the treatment of a patient with stage IIA non-bulky Hodgkin's disease by mantle irradiation. A consensus was present for the dose aims to involved and uninvolved lymph nodes and the acceptable incidence of late normal tissue effects. There was less agreement as to the total dose and dose per fraction required to maintain normal tissue toxicity within the agreed acceptable incidence. Variation was found in the radiation technique employed, the amount of spinal cord shielding used, the prescription point, modifications if irradiation was given after chemotherapy, and the routine recording of dose and dose per fraction to the normal tissue at risk. This descriptive survey confirms the need for well designed quality assurance programmes and indicates the areas of particular uncertainty that currently exist.

The place of radiotherapy in stage I and IIA Hodgkin's disease (or radiotherapy revisited)

For the majority of patients presenting with early Hodgkin's disease, the chance of death due to their disease is related to prognostic factors, e.g. age, systemic symptoms, ESR bulk, number of sites of disease, histology, haemoglobin, lymphocyte count etc. More than 50% of those with Stage I and IIA disease fall into an intermediate prognostic category where a variety of initial treatment strategies--chemotherapy alone (CT), radiotherapy alone (RT) or a combination of chemotherapy and radiotherapy (combined modality therapy CMT) result in comparable survival rates. There is therefore increasing emphasis on incidence of relapse and treatment related morbidities rather than on survival alone when evaluating the role of different treatment for Hodgkin's disease. Radiotherapy has an essential part to play in any initial strategy aiming to keep relapse rate low, as chemotherapy alone has been demonstrated to be less effective in treating macroscopic disease. Late side-effects associated with radiation are largely associated with obsolete techniques involving very wide fields, high doses and large fraction size delivered to anterior structures within the thorax. The risk of second solid tumour appears related to the volume of radiation fields and the risk of cardiac damage is probably related to both total dose and dose per fraction delivered. There is still uncertainty as to the potential late toxicity of modern techniques, particularly in combination with chemotherapy. Increasingly numbers of patients are likely to be treated with initial CMT rather than RT alone to reduce relapse rates. The risk of leukaemia associated with CMT to patients with curable Hodgkin's disease appears to have been overestimated.(ABSTRACT TRUNCATED AT 250 WORDS)