A new study appearing in the Journal of Clinical Oncology by researchers from the Institute of Cancer Research in the UK has examined the effects of chemotherapy and radiotherapy in the largest known group of patients with Hodgkin's lymphoma
Researchers followed 5,798 British Hodgkin's lymphoma patients who were treated with chemotherapy in Britain between the years 1963 and 2001. Among those, 3,432 also received radiotherapy along with chemotherapy. The point of the study was to determine the risk of developing a second cancer among this patient population compared to the general population.
What they found was that of the entire cohort, 459 people were found to have developed a second cancer. The most commonly diagnosed cancers were:
-- Lung cancer
-- Non-Hodgkin's lymphoma
-- Leukemia
And they were all found to have occurred fairly equally.
Following chemotherapy alone, the risk of secondary cancer peaked between 5 and 9 years after treatment ended, but when a patient received chemotherapy and radiotherapy, the risk of secondary cancer remained high for at least 25 years or longer.
The only chemotherapy regimen that did not appear to raise the risk of secondary cancer was the ABVD regimen, but this may merely be a symptom of not being as old as some of the other Hodgkin's regimens.
Researchers concluded that chemotherapy alone presents a lower risk of developing a secondary cancer later in life than the combined modalities of chemotherapy and radiotherapy, and that risk all but disappears after 15 years.
Swerdlow AJ et al. Second Cancer Risk After Chemotherapy for Hodgkin's Lymphoma: A Collaborative British Cohort Study. JCO. doi:10.1200/JCO.2011.34.8268