Risk of second cancer after chemotherapy in Hodgkin lymphoma

The current study explored the long-term risk of second cancers following chemotherapy for Hodgkin lymphoma. This study concluded that while there is an increased risk it is lower than the risk with combined chemotherapy and radiation.

New treatments for Hodgkin lymphoma have resulted in it being a curable disease. Patients are surviving for long periods following treatment. These treatments can increase the risk of long-term complications, including second cancers. Radiation and certain types of chemotherapies are known to increase these risks. Because chemotherapy is so often used in combination with radiation, it can be hard to determine the risks associated with that treatment alone.

This study examined the risk of second cancers in Hodgkin lymphoma survivors treated with only chemotherapy. This study examined the records of 5,798 patients. 2,364 of these patients were treated with chemotherapy alone. The rest were treated with chemotherapy and radiation.

459 patients developed second cancers. Patients treated with chemotherapy alone had 2 times the expected risk of second cancers. This was lower than patients treated with chemotherapy and radiation, who had 3.9 times the expected risk.

Patients treated with chemotherapy alone had increased risks of lung cancer, leukemia, and non-Hodgkin lymphoma. This risk peaked 5 to 9 years after treatment. In patients treated with chemotherapy and radiation, the risk of second cancer was raised for 25 years or more after treatment.

The risk of breast cancer was associated with the age at treatment. The risk was highest in patients treated with chemtherapy and radiation before the age of 20. The risk decreased with increasing age. Chemotherapy alone was not assiciated with an increased risk of breast cancer.

This study concluded that while chemotherapy does increase the risk of second cancers, the risk is higher when chemotherapy is combined with radiation.