NIH Study Finds Increased Leukemia Risk Related to Other Cancer Treatments
Risk especially high among non-Hodgkin’s lymphoma survivors (Feb. 14)
A new study describes the pattern of risk for acute myeloid leukemia (AML). Over the past 30 years, adults treated with chemotherapy for other forms of cancer — notably non-Hodgkin’s lymphoma (NHL) — have shown an increased risk for developing AML as well.
The findings — from the National Cancer Institute (NCI), part of the National Institutes of Health — were published online in Blood.
The researchers noted that chemotherapy is often an effective treatment for cancer, and that the subsequent risk of leukemia is generally low for an individual patient. The authors indicated that the increased risk among NHL survivors could be due to prolonged survival in recent years for some lymphoma subtypes that are associated with multiple courses of chemotherapy.
Over the study period, the researchers observed a declining risk among patients treated for ovarian cancer, myeloma, and possibly lung cancer. The decreased risk among patients with ovarian cancer is consistent with a shift from the use of the alkylating agent melphalan to platinum-based chemotherapy in the early 1980s.
“It has long been known that some types of chemotherapy are associated with a high risk of developing subsequent leukemia, particularly when treatments include certain alkylating agents,” said lead author Lindsay Morton, PhD. “The goal of this study was to better understand how cancer patients’ risk of developing leukemia has changed over time.”
The researchers also found evidence that the risk of treatment-related AML has increased since 2000 among patients treated for esophageal, prostate, and cervical cancer and since the 1990s among patients treated for cancers of the bones and joints and of the endometrium.
Morton and her colleagues used data from the NCI’s Surveillance Epidemiology and End Results (SEER) cancer registries to evaluate the risk of leukemia in more than 426,000 adults who had been diagnosed with cancer between 1975 and 2008 and who had received chemotherapy as part of their initial cancer treatment. The authors identified 801 patients who subsequently developed AML. Because the data came from SEER cancer registries, information on specific drugs used to treat each individual patient was not available. A unique feature of the study was the ability to evaluate leukemia risks in a large number of patients treated with chemotherapy in the current treatment era (2001 to 2008).
The researchers said it is important to identify patient groups that have the highest risks of treatment-related leukemia — particularly for patients with cancers that have favorable survival potential — so that efforts to prevent a return of the disease can be implemented where possible.
Future studies are needed to gather information on the risks associated with specific chemotherapy agents, which could not be obtained from this study, the investigators said.
Source: NIH; February 14, 2013.