Risk factors for the development of new cancers in patients with follicular lymphoma

This study looked at risk factors for the development of new cancers in patients who have follicular lymphoma. The authors concluded that being over 65 years old, being male, and receiving radiation therapy are the greatest risk factors for the development of a new cancer.

Follicular lymphoma (FL) is a common type of low-grade (slow-growing) non-Hodgkin lymphoma. While it is not considered curable, new treatments have led to very high long-term survival rates. Because people are living longer after treatment, it is important to monitor for any new cancers, known as secondary primary malignancies (SMPs). These may be due to treatment or unrelated causes.

Previous studies have shown that approximately 14% of FL survivors will develop a SMP. This study was done before rituximab (Rituxan) biological treatment was introduced. More research is needed on the occurrence of SMPs with more modern treatments. 

The medical records of 15,517 patients were reviewed. All patients were diagnosed with follicular lymphoma. The average follow-up time was 71 months.

The 10-year overall survival rate (time from diagnosis to death from any cause) was 57.9%.

1,540 patients (9.9%) developed an SPM. The most commonly developed SMPs were Hodgkin lymphoma and acute myeloid leukemia.

The 10-year cumulative incidence (CI) of SPMs (probability of developing an SMP) was 11%. The 10-year CI for people aged over 65 was 13.9%. It was significantly higher than those younger than 65 (8.6%). The 10-year CI for men was 12.8%. It was significantly higher than for females (9.4%). The 10-year CI for patients who received radiation therapy as part of their treatment was 12.5%. It was significantly higher than patients who did not receive radiation therapy (10.5%).

The authors concluded that the main risk factors for the development of a new cancer in patients with follicular lymphoma are being aged over 65, being male, and treatment with radiation therapy.

Even if someone has every risk factor, it does not necessarily mean that they will develop an additional cancer. However, if you do have one or more risk factor, it is important to communicate these concerns with your doctor and continue to go to routine follow-up appointments.