Lymphoma is a malignancy (cancer) of white blood cells (lymphocytes), which most commonly develops in lymph nodes. It may also arise in other organs such as the gastro-intestinal tract (gut), bone, lung, brain, eye and skin. Lymphoma can develop at any age of life, including in childhood.
Lymphoma can be broadly split into two main subtypes, which are Hodgkins Lymphoma and Non Hodgkins Lymphoma. Within these two main groups, there are many subtypes, whose biological behaviour can vary from being very slow to progress (indolent); to very aggressive, requiring urgent attention.
The treatment options for lymphoma may range from observation only (for indolent lymphomas) to requiring very intensive chemotherapy for the more aggressive types, however many lymphomas require a combination of chemotherapy and radiation therapy for treatment.
What are the Causes of Lymphoma?
The incidence of lymphoma has increased over time. In the majority of cases, the underlying cause is unknown, but some lymphomas arise in patients who have impaired immune systems, either from immunodeficiency syndromes (lowering immunity to diseases), or from medication that causes them to be immunosuppressed. There is also evolving evidence that some viral infections are implicated in the development of certain lymphomas.
What are the Symptoms of Lymphoma?
Many lymphomas are found through a patient finding a painless swollen lymph gland (also called a lymph node), or lump, in the neck, armpit or groin. Some patients may also notice generalised symptoms such as feeling unwell, fever, drenching night sweats, loss of weight, and occasionally itch and intolerance of alcohol. Some patients feel completely well, and their lymphoma is only found by accident when being investigated for another condition.
What are the Treatments for Lymphoma?
Treatment is tailored to the type, and extent of lymphoma. Some very slow growing (indolent) lymphomas are observed, and only treated on progression. Many lymphomas are very sensitive to both chemotherapy and radiation therapy, and are managed with a combination of both treatment types. This may allow lower doses of chemotherapy and radiation to be used, to minimise the side-effects.
In some patients, high dose chemotherapy and stem cell (bone marrow) transplant may be used for lymphoma that has come back after initial treatment.
Lymphomas in children are usually treated in specialist units attached to children’s hospitals and are mainly treated with chemotherapy.
Radiation therapy is an effective treatment for lymphoma and is used in both the curative and palliative settings (ie to alleviate pain or other problems when the patient can’t be cured).
In general, lymphomas are very sensitive to radiation therapy, and as a result, respond to lower doses than would be used for other cancers such as prostate cancer, breast cancer or head and neck cancer. Treatment courses may vary from one or two treatments to up to twenty treatments, depending on the type of lymphoma and the goal of treatment. In general, a course of radiation therapy is usually delivered daily, Monday to Friday.
Radiation therapy may be used as a stand alone, curative treatment for localised, low grade non-Hodgkin lymphoma. It can also used to palliate symptomatic lymphoma deposits which may be painful, bleeding, or affecting an organ’s function (e.g. lymphoma deposits obstructing a lung). Many patients with early Hodgkin Lymphoma are treated with between two to four cycles of chemotherapy, followed by localised, targeted (involved site or involved node) radiation therapy to the site of the lymphoma.
PET-CT scanning usually helps your Radiation Oncologist decide where your radiation therapy should be delivered to by improving the accuracy of target delineation . This may mean less risk of side-effects in the long term, with the same, or better chance of cure.
What are the Side Effects of Radiation Therapy?
In general, the development of side effects during treatment are related to the site being treated and usually becomes apparent towards the end of treatment. For many patients who are having a very low dose of radiation therapy given, they may not notice any side effects. Alternatively, if a lymph node group is irradiated to a higher dose, the patients may experience some redness of the overlying skin, transient loss of hair and mild fatigue. Other side effects are related to organs which are close to the lymphoma mass or involved by lymphoma.
Your Radiation Oncologist will outline any potential side effects related to the treatment site during the consultation. However, any side effects which appear during radiation therapy or shortly afterwards, are usually self-limiting and resolve within two to three weeks.
Early side effects which appear during radiation therapy or shortly afterwards, are usually self-limiting and resolve within three to four weeks after radiation therapy.
Late (long term) side-effects are relatively uncommon and may occur many months to years after treatment is completed. Many lymphoma patients are long term lymphoma survivors, so monitoring these patients to detect the development of late side effects and offer appropriate intervention is an important aspect of follow-up care. This is especially important for childhood lymphoma patients, who may be followed up long term through specialist late effects clinics. Recent advancements in chemotherapy and radiation therapy have been made to limit the rates of late side effects.
Likely late side-effects
Symptoms such as fibrosis (scarring/thickening) of muscles, skin dryness and atrophy, loss of taste and poor saliva production are less common now due to more targeted delivery techniques, smaller radiation therapy treatment volumes, and lower doses.
Hypothyroidism (underactive thyroid gland) is a late complication of radiation therapy of the head and neck region, and can present with nonspecific symptoms such as fatigue, weight gain and cold intolerance. It is managed with thyroid replacement therapy and monitored with blood tests and thyroid ultrasounds.
Cardiovascular (heart and blood vessel) disease can also develop many years after radiation therapy to the heart and large vessels such as the carotid arteries. Long term survivors require regular checks of their heart health
Rare late side-effects
Cancers occurring after the original lymphoma (second malignancies) may develop due to an inherent gene sensitivity which has caused the initial lymphoma, or as a result of the original anti-cancer therapy itself (chemotherapy or radiation therapy). If radiation-induced, these second malignancies are rare, occurring within the irradiated field, and after a long latency period (15-20 years later).
Breast cancer rates are increased in young women aged less than 30 years who have had radiation therapy for Hodgkin’s Lymphoma. For this reason, Radiation Oncologists will have a detailed discussion with these patients to weigh up the pros and cons of radiation therapy. Other new cancers may arise in organs that were irradiated many years ago, such as bowel, lung and soft tissue. Skin cancers may develop in skin over the irradiated site. Modern technology has allowed for radiation techniques to become more targeted and precise; and the doses have been decreased, therefore decreasing the risk of second cancer development.
Other less common or rare side effects (depending on the site treated and the age of the patient) include:
Neurocognitive (learning and memory) problems
How Do I Enquire About Radiation Therapy with My Healthcare Professional?
The best person to discuss radiation therapy with for Lymphoma is a Radiation Oncologist. You can ask your Surgeon or General Practitioner for a referral to a Radiation Oncologist for a discussion about whether radiation therapy is a suitable treatment for you.
Find your closest radiation oncology Treatment Centre
Page last updated: 13 July 2020