Follicular lymphoma: symptoms, diagnosis and treatment in the UK

Lymphoma is a cancer of the lymphatic system, which is part of the immune system. Cancer Research UK explains that follicular lymphoma develops when the body makes abnormal B lymphocytes, a type of white blood cell. The abnormal cells build up in the lymph nodes or other organs and do not work properly. Doctors call it follicular because the cells usually develop in clumps called follicles.

It is the most common type of low grade lymphoma. About 2,300 people are diagnosed each year in the UK, and around 20 in 100 of all people with non-Hodgkin lymphoma have the follicular type. It mainly affects adults over the age of 60.

Because it usually grows slowly, the question in many cases is not how quickly to treat it but whether treatment is needed yet. This is a major difference from fast-growing lymphomas, which the NHS says need to be treated straight away.

Lymphoma Action, a UK lymphoma charity, adds that follicular lymphoma can develop at any age but is more common in people over 60. In most cases there is no known cause, there is not normally any family history of follicular lymphoma, and some genetic changes are common in the lymphoma cells even though scientists do not know what causes them.

Cancer Research UK says some people have symptoms and some do not. The most common symptom is one or more painless swellings in the neck, armpit or groin. The NHS lists the same, along with a high temperature or feeling hot, cold or shivery, night sweats, shortness of breath, itchy skin and sudden unexplained weight loss.

General symptoms known as B symptoms include heavy night sweats, high temperatures that come and go with no obvious cause, and losing a lot of weight, more than one tenth of body weight. Tiredness can also occur. If the lymphoma involves the bone marrow it may cause anaemia, with tiredness or breathlessness, or low platelets, causing bruising or bleeding problems.

The NHS says to see a GP if you think you might have symptoms, as many are common and have other causes, but finding lymphoma early means treatment is more likely to be successful. The GP will ask about symptoms, may feel for lumps in the neck, armpit and groin, may arrange a blood test and may make an urgent referral, which does not definitely mean you have cancer.

Lymphoma Action says the swollen lymph nodes are usually painless and may stay swollen or shrink a little and then come back from time to time. Around half of people have lymphoma cells in the bone marrow when they are diagnosed, which can lead to anaemia (tiredness and shortness of breath), a low platelet count (more bruising and bleeding) or a low neutrophil count (more infections). Because it grows slowly and may cause no symptoms, it is often advanced (stage 3 or 4) by the time it is diagnosed, and there are treatments for all stages.

The main test is a lymph node biopsy. The NHS says part or all of a lymph node is removed (excision biopsy), or a sample of cells is taken with a thin needle, usually under local or general anaesthetic, and results should be available within 2 weeks. Cancer Research UK adds that a specialist examines the tissue under a microscope and that blood tests may be done.

If lymphoma is diagnosed you may have a PET-CT scan and a bone marrow test, according to Cancer Research UK, and the NHS lists blood tests and CT, MRI or ultrasound scans. These show how far the lymphoma has spread, called staging. Doctors usually describe four stages, with stage 1 or 2 called early (limited) and stage 3 or 4 called advanced.

Follicular lymphoma is also graded 1, 2 or 3, with grade 3 split into 3A and 3B. Grades 1, 2 and 3A are low grade and treated in the same way, while grade 3B grows faster and is usually treated similarly to high grade lymphoma. Doctors may also use a score called the Follicular Lymphoma International Prognostic Index (FLIPI), based on factors such as age, stage and some blood results, to talk about outlook and likely response to treatment.

Cancer Research UK says treatment depends on the stage. At diagnosis your doctor assesses whether you need treatment straightaway, and if so which is best.

• The NHS says treatment for slow-growing lymphoma does not get rid of it but can keep it under control for many years, and that treatment may include chemotherapy, targeted medicines, immunotherapy, radiotherapy and stem cell transplant.

• Some treatment for non-Hodgkin lymphoma can affect fertility, and the NHS advises speaking to your specialist team before treatment if you may want children in the future.

Active monitoring means regular check-ups instead of treatment. Cancer Research UK says doctors choose it because you have no troublesome symptoms, the lymphoma can be very slow growing, and all treatment has side effects. You might have appointments every few months at first, with an examination and blood tests, and you start treatment if symptoms appear or the lymphoma gets worse. It can be difficult to cope with not having treatment after being told you have lymphoma, and support is available.

Cancer Research UK says follicular lymphoma tends to come back at some point, but you may not need treatment straight away if you have no symptoms. Second and later remissions are usually shorter than the first.

Over time, a low grade lymphoma can sometimes change into a faster-growing high grade lymphoma, called transformation. It does not always happen and, if it does, it might be many years after the first diagnosis.

Lymphoma Action says treatment is generally successful and long remissions are possible, but at some point the lymphoma usually comes back and needs more treatment. Most people live with follicular lymphoma for many years and it is managed as a long-term (chronic) condition, with periods of feeling well and not needing treatment alongside periods needing more. On transformation, it says this happens in 2 to 3 people in every 100 with follicular lymphoma each year, and that a transformed lymphoma is usually treated like a high-grade lymphoma such as diffuse large B-cell lymphoma.

Being told you have a cancer but do not need treatment can be confusing. The NHS says you will be helped by a team of specialists that usually includes a clinical nurse specialist, who is your main point of contact during and after treatment. Macmillan Cancer Support, according to the NHS, runs a free helpline for anyone who wants to talk.

Cancer Research UK says survival depends on many factors and that no one can tell you exactly how long you will live. Your specialist is the best person to talk to about prognosis, and not everyone wants that information, which is a personal choice.

On the NHS, a GP refers suspected lymphoma to haematology for biopsy, staging and a multidisciplinary team decision. Tests and treatment, including rituximab and chemotherapy, are free at the point of use, and monitoring is shared between hospital and GP.

Some people seek a private consultation or second opinion about whether to monitor or treat, or about trial options. It helps to ask your specialist team about clinical trials, which Cancer Research UK says doctors may suggest, and to share your scan and pathology reports with any second clinician.