The management of Hodgkin lymphoma continues to change. Before the widespread use of modern polychemotherapy, radical radiation therapy alone cured many patients. However, reliance on radiation alone required extensive radiation portals to treat nearly the entire lymphatic system with radiation doses up to 44 Gy. With long-term follow-up, many of these patients developed heart toxicity and second malignancies.
Over the past 10 to 20 years, efforts have been made to reduce the long-term toxicities of treatment for Hodgkin lymphoma, while maintaining excellent cure rates. With modern chemotherapy, multiple randomized studies have shown that radiation portals can be safely reduced from extended-field radiation to involved-field radiation. This is very important to reduce the risk of secondary breast cancers in young women. The majority of breast exposure to radiation is from treating the axillary nodes with large mantle fields. Because most women with early stage Hodgkin lymphoma do not present with axillary adenopathy, eliminating radiation to the axilla will decrease the risk of secondary breast carcinomas. In addition, several centers are using novel treatment techniques, such as innovative patient positioning systems to move the breasts out of the field, intensity-modulated radiation therapy and proton radiation to further reduce exposure of normal tissues to radiation. Currently, the European Organization for Research and Treatment of Cancer (EORTC) has further reduced the radiation portals from involved-field to involved-nodal radiation, where the portal is tailored to the involved node only and not the entire lymph node region. In addition, studies are also currently underway to determine if it is possible to reduce the radiation dose after chemotherapy from 30 to 20 Gy. Thus, the radiation portals are much smaller, more conformal, and the doses are lower than those 20 to 40 years ago.
In multiple studies in patients with early-stage Hodgkin lymphoma, the complete omission of radiation therapy resulted in an inferior outcome. In the future, functional imaging such as positron emission tomography may allow the identification of patients in whom radiotherapy can be eliminated, but this is still being examined in carefully controlled clinical trials. However, radiation therapy with greatly revised techniques and lower doses will likely continue to play an important role in the management of Hodgkin lymphoma.
Over the past decade, investigators have made significant progress in the diagnosis, classification, staging, prognosis, and treatment of Hodgkin lymphoma (HL). In past years, the true lineage of the neoplastic cells in HL was unknown, hence the term "Hodgkin disease" was used. It is now recognized that almost all cases of HL are of B-cell lineage, hence the name change to HL.
The classification of HL has remained relatively stable over the past 40 years and the World Health Organization (WHO) classification of lymphoid neoplasms was updated recently in 2008 (1) (Table 10-1). The current WHO classification recognizes that nodular lymphocyte predominant HL (NLPHL) is distinct from the other types that can be grouped together under the ...