From the Guest Editor

Abstract

Hodgkin’s lymphoma was once a uniformly fatal disease. However, today at least 80% to 85% of all patients are cured. No stage of disease is beyond cure. Patients may even be cured after they have relapsed. Indeed, anecdotal data make it difficult to ever throw in the towel in managing patients with Hodgkin’s lymphoma. When one sees a patient who has been in her fifth complete remission for 26 years, it makes one reluctant to ever say “never.” Even when the physician has exhausted the conventional curative approaches, palliative therapy may also produce long periods of symptom-free survival. The paradoxical outcome from this success is that it makes the death of a patient with Hodgkin’s lymphoma much more difficult to bear. For many advanced cancers, death is the expected outcome and when it comes, it is painful to be sure, but the physician has been preparing himself or herself, the patient, and the patient’s family for the event. When a patient with Hodgkin’s lymphoma dies, it is often an even more devastating blow because the course of treatment was embarked upon with such high hopes. Despite the enormous progress that has been made in successfully treating patients with Hodgkin’s lymphoma, our knowledge about the disease is far from comprehensive. Furthermore, even the information we know about Hodgkin’s lymphoma and its treatment is not agreed upon. Controversy surrounds the decision on the best treatment approach. In this issue of The Cancer Journal, I have been fortunate to collect the thoughts of many of the leading figures in Hodgkin’s lymphoma in the world. Their contributions here will bring the reader up to date on the facts and opinions of many experienced thought leaders. What causes Hodgkin’s lymphoma? We don’t know. However, in these pages, Neil Caporaso and his colleagues from the National Cancer Institute (NCI) discuss what has been revealed from studies of the epidemiology of the disease. Genetic factors contribute to the disease, but we do not know precisely what genes are involved or how they lead to the tumor. A higher incidence occurs in westernized populations including those who emigrate from low-incidence sites to the United States. Efforts to find an infectious etiologic agent have been largely unsuccessful, though a role for Epstein-Barr virus has been implicated in some cases. How does Hodgkin’s lymphoma present and progress? Fortunately, we have Joseph Connors, a master clinician and clinical researcher at the British Columbia Cancer Agency, to draw on his own vast experience and the world literature on the clinical manifestations and natural history of Hodgkin’s lymphoma. The disease has a predilection for lymph nodes. If only a single site is involved, it is usually the left supraclavicular node region. The disease marches progressively from one lymph node-bearing group to the next. When it spreads to the abdomen, usually the spleen is the first site involved. Because the spleen lacks afferent lymphatics, this may argue for hematogenous spread with selective growth in the fertile soil of the spleen. Fever, weight loss, and night sweats reflect systemic effects from tumor-induced cytokines. The disease may also be associated with important alterations in other organs including nephrotic syndrome and neurologic symptoms. What is Hodgkin’s lymphoma? As discussed in detail by the NCI’s Franziska Eberle, Haresh Mani, and Elaine Jaffe, Hodgkin’s lymphoma currently seems to be at least 2 diseases, as reflected in the World Health Organisation classification of lymphoid malignancies: the more common classic Hodgkin’s lymphoma and the much less common nodular lymphocyte predominant Hodgkin’s lymphoma. However, more recent evidence suggests that classic Hodgkin’s lymphoma may be a heterogeneous category with at least 2 diseases, nodular sclerosis representing 1 subset and mixed cellularity and lymphocyte depleted types forming a continuum on the other. Reliably distinguishing these entities is the first step toward sorting out their pathogenesis and perhaps defining new therapeutic targets for the subset of patients not cured by existing approaches. The staging of the extent of disease has undergone changes through the years as therapy has produced better results and nearly all patients receive some systemic therapy. Thus, removed from