Lymphoma subtypes: Can you spot the difference?

Non-Hodgkin lymphoma (NHL) is a type of blood cancer that starts in the white blood cells, known as lymphocytes, which are a key component of the immune system.¹ There are over 60 different types of NHL,² which can also be classified as indolent (slow growing) or aggressive (fast growing), depending on how quickly the cancer grows.³ Two of the most common types, follicular lymphoma and diffuse large B-cell lymphoma (DLBCL), are very different in how, when and where they develop and how they are managed.

What are the most common subtypes of NHL?

Follicular lymphoma
Follicular lymphoma is the most common indolent lymphoma, accounting for around 20% of newly diagnosed NHL cases. Worldwide this is equivalent to approximately 100,000 people being diagnosed with this subtype each year. ⁴,⁵
Diffuse large B-cell lymphoma
DLBCL is the most common form of aggressive NHL, accounting for 30% of newly diagnosed NHL cases. Worldwide this is equivalent to approximately 170,000 people being diagnosed with this subtype each year. ⁴,⁵

How do cancer cells differ between subtypes?

Follicular lymphoma
Follicular lymphoma is a type of B-cell lymphoma. It's called follicular because cancer cells tend to clump together in circles, known as follicles, in the lymph nodes.⁶
Diffuse large B-cell lymphoma
DLBCL is a type of B-cell lymphoma. It's called diffuse because cancer cells spread out within the tumour, destroying the normal structure of the lymph node.⁷

How quickly does the disease progress?

Follicular lymphoma
Follicular lymphoma is an indolent form of NHL, which means it grows slowly. Patients with follicular lymphoma can survive for many years and may only require active surveillance with no immediate treatment if they do not display symptoms.⁸
Diffuse large B-cell lymphoma
DLBCL is characterised as aggressive because it advances rapidly and invariably becomes fatal without immediate treatment.⁹ If DLBCL is left untreated, median survival is less than one year.¹⁰

When are patients usually diagnosed?

Follicular lymphoma
Symptoms of follicular lymphoma often appear gradually and therefore go unnoticed by patients, resulting in 80% of patients being diagnosed in the advanced stages of disease.¹¹
Diffuse large B-cell lymphoma
Due to the aggressive nature of DLBCL, symptoms such as enlarged lymph nodes often apparent early on. Around 40% of patients are diagnosed in the early stages of the disease, when prognosis is better.⁹

What is the course of the disease?

Follicular lymphoma
Although most patients respond to initial treatment, follicular lymphoma usually recurs and becomes more difficult to treat after each relapse.¹² Relapse can occur at any time, even after years in remission.
Diffuse large B-cell lymphoma
DLBCL is highly responsive initially with over 60% of patients having long lasting responses.¹³ Patients who relapse have poor survival, but those that respond to treatment and remain progression-free after two years have a life expectancy considered comparable to healthy people of the same age. ¹³,¹⁴

What is the unmet clinical need?

Follicular lymphoma
The aim of treatment is to prolong the time before a person's disease returns. Treatment options that minimise symptoms and keep patients in remission longer are needed to improve long-term outcomes.¹⁵
Diffuse large B-cell lymphoma
The aim of treatment in DLBCL is to achieve long lasting responses. New treatment options are needed to increase initial long lasting response rates and improve long-term outcomes when the disease returns for those who fail frontline therapy.¹⁶

References

  1. Lymphoma research foundation. [Internet; cited April 2022]. Available at: https://www.lymphoma.org/aboutlymphoma/

  2. Swerdlow SH, et al. WHO classification of tumours of haematopoietic and lymphoid tissues. In: World Health Organization Classification of Tumours. Lyon, France: IARC; 2017.

  3. American Cancer Society. What is Non-Hodgkin Lymphoma. [Internet; cited April 2022]. Available at: https://www.cancer.org/cancer/non-hodgkin-lymphoma/about/what-is-non-hodgkin-lymphoma.html

  4. Cancer.Net. Leukemia – Lymphoma –Non-Hodgkin: Subtype. [Internet; cited April 2022]. Available from: https://www.cancer.net/cancer-types/lymphoma-non-hodgkin/subtypes.

  5. Globocan 2020. World fact sheet. [Internet; cited April 2022]. Available at: http://gco.iarc.fr/today/data/factsheets/populations/900-world-fact-sheets.pdf

  6. Rare Diseases. [Internet; cited April 2022] Available at: https://rarediseases.org/rare-diseases/follicular-lymphoma/.

  7. Lymphoma Action. [Internet; cited April 2022]. Available at: https://lymphoma-action.org.uk/sites/default/files/media/documents/2018-06/LYMweb0018DLBCL2016v2.2.pdf.

  8. Lymphoma Research Foundation. [Internet; cited April 2022]. Available at: http://www.lymphoma.org/site/pp.asp?c=bkLTKaOQLmK8E&b=6300155 Last accessed September 2016

  9. UpToDate. Patient education: Diffuse large B cell lymphoma in adults (Beyond the Basics). [Internet ; cited April 2022]. Available at: https://www.uptodate.com/contents/diffuse-large-b-cell-lymphoma-in-adults-beyond-the-basics.

  10. Rovira J et al. Prognosis of patients with diffuse large B cell lymphoma not reaching complete response or relapsing after frontline chemotherapy or immunochemotherapy. Ann Hematol. 2015; 94: 803–812.

  11. National Institute for Health and Clinical Excellence Review of TA 110:rituximab for the first-line treatment of stage III-IV follicular lymphoma. [Internet; cited April 2022]. Available at: https://www.nice.org.uk/guidance/ta243/documents/follicular-lymphoma-rituximab-review-lymphoma-association2.

  12. Lymphoma Research Foundation. [Internet; cited April 2022]. Available at: https://www.lymphoma.org/aboutlymphoma/nhl/fl/relapsedfl/.

  13. Maurer, MJ et al. Event-free survival at 24 months is a robust end point for disease-related outcome in diffuse large B-cell lymphoma treated with immunochemotherapy. J Clin Oncol. 2014; 32: 1066-73.

  14. Maurer MJ, Habermann TM, Shi Q, et al. Progression-free survival at 24 months (PFS24) and subsequent outcome for patients with diffuse large B-cell lymphoma (DLBCL) enrolled on randomized clinical trials. Ann Oncol. 2018;29:1822-1827.

  15. Fowler N. Role of Maintenance Rituximab (Rituxan) Therapy In the Treatment of Follicular Lymphoma. Pharmacy and Therapeutics; 2011; 36:590-598

  16. Lymphoma Action. Diffuse large B-cell lymphoma. [Internet; cited April 2022]. Available at: https://lymphoma-action.org.uk/types-lymphoma-non-hodgkin-lymphoma/diffuse-large-b-cell-lymphoma.