8 things you didn't know about lymphoma

Lymphoma is a type of haematological cancer that occurs when certain white blood cells (lymphocytes) begin to grow uncontrollably and accumulate in the lymph nodes. Lymphoma is not a single pathology, but actually a group of different diseases, with different clinical behaviours and treatments.

White blood cells, or leukocytes, are produced by the bone marrow and help defend the body against infection. When these white blood cells divide abnormally or grow uncontrollably, it causes leukaemia or lymphoma.

Currently, lymphoma accounts for 4% of all new cancer cases in Spain. It is rare compared to the most common cancers. However, there are many questions surrounding lymphoma and, above all, its treatment. Here are 8 things you didn't know about lymphoma:

What is the difference between leukaemia and lymphoma?

Lymphomas are malignant tumours originating in the lymph nodes or other lymphoid tissue. They appear as an enlargement of the lymph nodes in the neck, armpits, groin, chest or abdomen. Leukaemia, on the other hand, originates in the bone marrow and causes alterations in the blood. However, lymphoma can also affect the bone marrow and blood. Leukaemia and lymphoma are more or less equal in severity, although this depends on the specific case of each one.

Can previously untreatable lymphoid leukaemia or lymphoma be treated with the new therapies available?

Many haematological diseases are chronic or incurable despite the new treatment options that exist. For example, follicular lymphoma and chronic lymphocytic leukaemia (CLL) have effective treatments for controlling tumour growth, but not for eradicating the disease. Many patients with these diseases can still live many years, some even without receiving any treatment. Therefore, although new treatments for these diseases are available, the criteria for starting any of them remain the same.

Is it true that reducing sugar consumption or even fasting can prevent cancer cells from feeding?

Any healthy, balanced diet must contain a controlled proportion of sugars, fats and salt. The claim that sugar feeds lymphoma cells has no scientific basis. In fact, many cells in our body, such as brain cells, depend entirely on carbohydrates to function, so a carbohydrate-free diet is not recommended or sustainable in the long term for patients with blood diseases.

However, some fasting regimens have shown some initial benefits in the general population. Nevertheless, the lack of studies in patients with lymphoma and the fragility of some of them do not allow fasting to be recommended.

What new treatments are available for lymphoma?

There has been a general explosion in recent years in the therapeutic options for cancer, and for lymphoma in particular. The use of chemotherapy has been reduced and replaced by much more specific treatments. For example, chronic lymphocytic leukaemia (CLL), which shares many features with lymphoma, is treated with drugs that specifically target the tumour cell, such as anti-CD20 antibodies, BTK inhibitors and BCL2 inhibitors. Other compounds with targeted action are used in lymphoma, such as lenalidomide, tazemetostat, as well as immunotherapy.

What role does immunotherapy play in the treatment of lymphoma?

Immunotherapy is based on modifying the immune system cells to combat a tumour. There are many types of immunotherapy, depending on how they work:

Monoclonal antibodies: These attack a protein on the surface of the lymphoma cell.

Immune checkpoint inhibitors: These trigger natural immune control mechanisms.

Bispecific antibodies: These bind to the tumour cell and an immune system cell, thus facilitating the recognition and destruction of tumour cells.

CAR-T therapy: The patient's immune cells are genetically modified to target a protein on the surface of lymphoma or leukaemia cancer cells.

Bone marrow transplant: Immune cells from a donor are used to fight tumour cells in the recipient.

Does immunotherapy have any side effects, as with chemotherapy?

Immunotherapy can also cause side effects. It does not produce the adverse effects typically associated with chemotherapy, such as nausea or hair loss. However, it can have other effects, such as infusion reactions, loss of sensitivity, diarrhoea, infections and fever. Some of these reactions can even put the patient's life at risk.

Given that immunotherapy can be used, why is chemotherapy still needed?

A large proportion of patients still respond very well to chemotherapy and can even be cured by it. Also, extensive experience with chemotherapy means its adverse effects are known and better managed. Finally, since immunotherapy is a more recent development, it places a much greater financial burden on the public health system.

What role does bone marrow transplant play in CLL and lymphoma?

For patients with lymphoma who have had CAR-T therapy approved, bone marrow transplants are reserved for those who have had multiple relapses after immunotherapy treatment. For other lymphoma cases for which immunotherapy is less developed, a bone marrow transplant is an option to be considered, especially for young, physically fit patients.