The lymphomas are a heterogenous group of neoplastic disorders of the lymphatic system of which there are two main types; Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL). Hodgkin's lymphoma was formerly called Hodgkin's disease after Thomas Hodgkin who first described it in 1832. It is rare, representing less than 1% of newly diagnosed cancers, with bimodal peaks in early adulthood and the elderly, and occurring slightly more frequently in males than females. The incidence of non-Hodgkin's lymphoma has been increasing steadily for the past 20 years for reasons that are as yet unclear (Evans & Hancock, 2003) and it currently accounts for approximately 4% of newly diagnosed cancers (Webster & Cella, 1998) in North America and western Europe where it is more common than in other regions of the world. Prevalence of NHL increases with age and there is a higher incidence in males (Evans & Hancock, 2003).

Treatment

Initial treatment of lymphoma generally involves chemotherapy often combined with involved-field radiotherapy. Courses of chemotherapy are spread out over several months, while radiotherapy is usually given five days a week for several weeks (see ‘Chemotherapy’ and ‘Radiotherapy’). Most HL patients can be cured (overall survival rate greater than 80% at 10 years, and better survival rates for early stage HL) (Yung & Linch, 2003). Cure rates for NHL vary from approximately 50% to 90% depending on type and stage (Sweetenham, 2003).