Low Risk of second Cancer Following Breast Cancer Treatment
A recent study reveals that while women diagnosed with breast cancer do face a slightly elevated risk of developing a second cancer, the overall risk remains relatively low and is often outweighed by the benefits of treatment. The research,focusing on long-term outcomes,found that approximately 13.6% of women developed a non-breast cancer - specifically of the uterus, lung, or intestine – following a breast cancer diagnosis. This represents a 2.1% increase compared to the general population. Additionally, 5.6% developed contralateral breast cancer (cancer in the other breast),a 3.1% higher rate than expected in the broader population.
The study highlighted that the most common secondary tumors were located in the uterus,lung,and intestine. Researchers observed that the increased risk of a second breast cancer didn’t significantly vary based on age at initial diagnosis, but the risk of contralateral breast cancer was notably higher in younger women.
Specifically, a woman diagnosed with breast cancer at age 60 has an estimated 17% risk of developing a non-breast cancer and a 5% risk of contralateral breast cancer by age 80, compared to 15% and 3% respectively for women in the general population. For a woman diagnosed at age 40, the estimated risks at age 60 are 6% for both non-breast and contralateral breast cancer, compared to 4% and 2% for the general population.
The research also investigated the impact of treatments. radiotherapy was linked to increased rates of contralateral breast and lung cancer, endocrine therapy was associated with uterus cancer (but also a reduction in contralateral breast cancer), and chemotherapy was linked to acute leukemia. Researchers estimate that approximately 7% of the excess second cancers could be attributed to these adjuvant therapies. However,they emphasized that this “little risk” is consistently outweighed by the notable benefits of these treatments when recommended.The authors stressed the importance of transparent communication, stating, “Risk information should be easily available. [It] helps plan our lives and to think about the future.” They also acknowledged potential limitations in their findings, including incomplete cancer registry data and a lack of information regarding family history, genetic predisposition, and lifestyle factors like smoking.The findings have been echoed by Self-reliant voice,a UK-based institution representing cancer patients,who published an opinion piece emphasizing the need to share this “reassuring” information. They noted that “Many patients with breast cancer believe that their risks of a second cancer are much greater than they really are” and that the study’s results, demonstrating a low risk, should be widely disseminated to alleviate patient anxieties.