The risk of a second cancer remained high even 30 years after treatment.
Hodgkin lymphoma cancer survivors are 2.4 times more likely to develop a second type of cancer.
In a study published in the Journal of Clinical Oncology, investigators found that the risk of developing a second cancer of any type is higher among survivors of Hodgkin lymphoma compared with individuals of the same age and sex in the general population, especially in those with a familial history of the disease.
For the study, investigators analyzed data from 9522 patients with Hodgkin lymphoma and 28,277 relatives of these patients. Approximately 30% of the participants with Hodgkin lymphoma had 1 or more first degree relatives with cancer.
The results of the study showed that patients with a familial history of cancer were 2.8 times more likely to develop a second cancer compared with patients with no first-degree relatives with cancer, who were 2.2 times more likely to develop a second cancer. Individuals with 2 or more first-degree relatives with cancer were 3.4 times more likely to develop a second cancer.
The most commonly found second cancers were non-Hodgkin lymphoma, leukemia, non-melanoma skin cancers, and lung, breast, and bowel cancer.
Patients treated for Hodgkin lymphoma who had a close relative with lung cancer were 3 and a half times more likely to develop lung cancer compared to those without. Patients with a familial history of breast or bowel cancer had an approximately 2-fold increased risk of developing cancer.
“People with Hodgkin’s lymphoma are at a greater risk of developing a second cancer, particularly in those who were treated with radiotherapy approach that was used a few decades ago,” said Martin Ledwick, head cancer information nurse at Cancer Research UK. “A family history of breast cancer adds to their risk. This study is the first to show that a family history of lung and bowel cancer also plays a role.
“The research shows that a family history of lung cancer carries the highest risk, and as the risk hasn’t decreased as treatment has changed to use less radiotherapy, there may be factors other than heredity, such as family smoking habits, that are influencing the risk.”
The investigators also observed a link between the increased risk of a second cancer and the age at diagnosis for both women and men.
Women diagnosed with Hodgkin lymphoma younger than 35 years had a 14% risk of developing breast cancer over the next 30 years, whereas, patients older than 35 years at diagnosis had a 3% risk.
“The vast majority of patients with Hodgkin lymphoma are cure with a combination of chemotherapy and radiotherapy,” said author Dr Amit Sud. “Our research has shown that these patients are at substantially increased risk of a second cancer later in life—–and particularly if they have a family history of cancer.
“Younger women who have been treated with radiotherapy to the chest for Hodgkin lymphoma are already screened for breast cancer, but our study suggests that we should be looking at ways of monitoring survivors for other forms of cancer too, and potentially offering preventative interventions. After patients are cured, they no longer encounter oncologists, so it’s important that other health care providers are aware of the increased risk to Hodgkin lymphoma survivors to improve early diagnosis of second cancers.”
Cancer treatments are continuing to improve and patients are surviving longer. As a result, there has been an increased focus on the long-term health of survivors.
“As cure rates for cancer improve, we are increasingly thinking about the long-term health of survivors, and how we can personalize the care they receive to take into account their own individual risks,” said Richard Houlston, a professor at The Institute of Cancer Research. “This major new study has tracked the health of people who have survived Hodgkin lymphoma over several decades in order to provide a comprehensive assessment of the long-term risk of cancer. The research gives un invaluable information which we can look to use to tailor monitoring, screening, or preventative treatment.”