Breast cancer survivors have increased rates of acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) compared with woman in the general population, according to a recent study published in JAMA Network Open.

The study also found higher rates of acute lymphoblastic leukemia or lymphocytic lymphoma (ALL/LL) and multiple myeloma (MM), highlighting the need of continuous monitoring for hematologic malignant neoplasms among breast cancer survivors.

Doctor talking with breast cancer survivor. Source: Getty

“Secondary malignant neoplasms, including hematologic malignant neoplasms, that develop for months or years after the diagnosis of a primary tumor, are increasingly becoming a concern given that the population of breast cancer survivors is growing substantially,” Marie Joelle Jabagi, PharmD, MPH, of the University of Paris Sud and the French National Agency for Medicines and Health Products Safety and colleagues wrote. “Such secondary cancers, reported since the early 1980s, may be a consequence of genetic predisposition, environmental factors, previous malignant neoplasm treatments, or an interaction among all those factors.”

The researchers added, “Breast cancer is classified as the most prevailing malignant solid tumor associated with the risk of myeloid neoplasm development.”

The study used data from the French National Health Data System, which includes information on all French residents’ health-related expenses. The study included 439,704 French women aged 20 to 85 years (median age, 59) with a breast cancer diagnosis between July 1, 2006 and December 31, 2015. Study participants were followed up until hematologic malignant neoplasm occurrence, death, loss of follow-up, or December 31, 2016.

Researchers assessed for incidence of AML, MDS, myeloproliferative neoplasms (MPNs), MM, Hodgkin lymphoma or non-Hodgkin lymphom (HL/NHL), and ALL/LL occuring at least 6 months after breast cancer diagnosis.

During a median follow-up of 5 years, researchers observed 3,046 cases of hematological malignant neoplasms:

• 509 cases (16.7%) of AML (crude incidence rate [CIR] per 100 000 person-years, 24.5; 95% CI, 22.4-26.8),

• 832 cases (27.3%) of MDS (CIR, 40.1; 95% CI, 37.4-42.9),

• 267 cases (8.8%) of MPN (CIR, 12.8; 95% CI, 11.4-14.5),

• 420 cases (13.8%) of MM (CIR, 20.3; 95% CI, 18.4-22.3),

• 912 cases (29.9%) of HL/NHL (CIR, 44.4; 95% CI, 41.1-50.0), and

• 106 cases (3.5%) of ALL/LL (CIR, 5.1; 95% CI, 4.2-6.2).

Compared with the general population, breast cancer survivors had significantly higher incidences of  AML (standardized incidence rate ratio [SIRR], 2.8; 95% CI, 2.5-3.2) and MDS (SIRR, 5.0; 95% CI, 4.4-5.7). Researchers also observed higher rates — though to a lesser extent — of MM (SIRR, 1.5; 95% CI, 1.3-1.7]) and ALL/LL (SIRR, 2.0; 95% CI, 1.3-3.0) among breast cancer survivors.

“These findings serve to better inform practicing oncologists, and breast cancer survivors should be advised of the increased risk of developing certain hematologic malignant neoplasms after their first cancer diagnosis,” Jabagi and colleagues concluded. “Therefore, continuing to monitor hematologic malignant neoplasm trends is necessary, especially given that approaches to cancer treatment are rapidly evolving.”