The treatment of lymphoma is often complex and requires the input of a number of specialists including expert pathologists, radiologists, nuclear medicine physicians and clinicians. Optimal management involves close coordination of these specialists working together in a multi-disciplinary team. There have been recent significant advances in the diagnosis, staging and treatment of lymphoma which has resulted in better treatment outcomes.
This article is written by Dr Nick Maisey (MRCP, MD), consultant Medical Oncologist and Dr Paul Fields (FRCP, MRCPath, PhD), consultant Haemato-oncologist both based at the London Bridge Hospital, 27 Tooley Street, London SE1 2PR.
Lymphoma is not a single disease. There are many different ‘sub-types’ of lymphoma that can behave in very different ways and so may need different treatments. Some lymphomas are highly curable, and some run a slow indolent course. In order to best tailor an individual treatment approach, an accurate diagnosis is essential. Improvements in laboratory techniques (such as immunohistochemistry, cytogenetics, polymerase chain reaction (PCR) and micro-array technology) can now give us a much more accurate diagnosis. A further benefit of these improved techniques is the identification of potential molecular therapeutic characteristics that can help the development of new ‘targetted’ treatments.
An accurate assessment of the spread of lymphoma (or stage) is of paramount importance in planning any potential therapies. Disease that is limited to one or two parts of the body may allow a radical (or curative) approach with radiotherapy whereas the identification of wide-spread disease might mean that prolonged chemotherapy is needed. Scanning techniques (or imaging) such as computerised tomography (CT) or magnetic resonance imaging (MRI) have improved considerably and continue to do so. Not only does accurate imaging inform initial staging assessment but also allows careful assessment of the response to treatment. The introduction of Positron Emission Tomography (PET, Fig 1) has been a huge advance in the imaging of lymphoma. PET is a ‘functional imaging technique’ that is highly sensitive in detecting active lymphoma. It plays a number of important roles, from initial staging, early response assessment and the examination of scar tissue commonly left after treatment.
The goal of treatment is to offer the highest chance of cure, whilst limiting excessive or unnecessary treatments and side-effects. Although chemotherapy continues to play a crucial role in the treatment of lymphoma, the introduction of ‘immunotherapy’ has revolutionised both the chance of response and the long-term survival. Initially licensed for the treatment of aggressive lymphoma, Rituximab is now routine treatment for slow-growing lymphoma and is showing promise as a maintenance strategy following initial chemotherapy. Bortezomib (velcade) is an example of a drug that targets intracellular pathways and has found a role in the treatment of Mantle-cell lymphoma. An interesting therapeutic approach involves the targeting of radiotherapy to sites of lymphoma, by labelling monoclonal antibodies with radioactive nuclides. Treatment with drugs such as Ibritumomab (Zevalin) can now offer long periods of good quality remission after only 2 outpatient visits. In some cases of resistant lymphoma, Stem cell transplantation may offer the only chance of cure. A novel approach called reduced-intensity allogeneic transplantation, harnesses the effects of the immune system to eradicate disease rather than relying on very high doses of conventional chemotherapy drugs. This technique is beginning to demonstrate efficacy in relapsed Hodgkin’s disease and indolent non-Hodgkin’s lymphoma.
Huge strides have been made in the treatment of lymphoma, but ongoing research continues to unravel the biology of these complex diseases and the development of future treatment targets. The ultimate goal is to offer tailored treatment to individual patients, to optimise the chance of cure for this family of diseases.