Identification of risk factors in patients treated for first relapse of Hodgkin's disease

This review focuses on potential risk factors in patients relapsing with Hodgkin's disease after a first chemotherapy/radiation therapy induced complete remission. This patient group usually presents with highly treatment responsive disease and has become one of the target groups for consideration of salvage high dose chemotherapy with stem cell/autologous marrow support (HDC/ABMT). It is currently not clear to which patients in first relapse this treatment should be offered. The knowledge of certain risk factors could be of great help in assessing such patients. A first group of risk factors are those assessable at initial diagnosis: sex, age, histology, Ann Arbor stage, tumour bulk and some laboratory parameters. A second group of risk factors are those present at the time of relapse: time to relapse, extent of disease at relapse, B-symptoms and performance status, extra nodal lesions at relapse or a relapse within an irradiated field. Age below 50 years seems to exert a small influence on outcome but becomes a major problem above that. There is a small number of characteristics such as the time from the end of initial treatment to relapse or B-symptoms at relapse which seem to be the most prominent factors predicting for freedom from second failure (FF2F). Patients who relapse more than one year after finishing primary chemotherapy and who are free of B symptoms at relapse have a quite favourable outcome after salvage treatment. If their disease is not bulky and is confined entirely to a modest number of previously unirradiated lymph node sites, wide field irradiation offers a reasonable chance of disease control. If their recurrence is bulky, extra-nodal or in a previously irradiated site, the patient's prognosis after HDC/ABMT is excellent. Patients who relapse less than one year after primary chemotherapy or with B symptoms at the time of relapse have a less satisfactory outcome after any available salvage treatment. Trials comparing various HDC/ABMT regimens or novel approaches built on standard dose chemotherapy and irradiation are needed to find better treatments for such patients. Such patients with early or symptomatic relapses who cannot be enrolled in prospective comparative trials should be offered HDC/ABMT while we search for better treatments. Larger trials with a prospective analysis of the risk factors are needed for us to be able to decide which treatment will be the optimal choice for our patients.