Do breast implants adversely affect prognosis among those subsequently diagnosed with breast cancer? Findings from an extended follow-up of a Canadian cohort
Menée au Canada sur 853 patientes atteintes d'un cancer du sein, cette étude de cohorte évalue l'impact de prothèses mammaires sur le stade au diagnostic et la survie
Background:Cosmetic breast implants may impair the ability to detect breast cancers. The aims of this study were to examine whether implants and implant characteristics are associated with more advanced breast tumors at diagnosis and poorer survival. Methods:Study population includes all invasive breast cancer cases diagnosed during follow-up of the large Canadian Breast Implant Cohort. A total of 409 women with cosmetic breast implants and 444 women with other cosmetic surgery were diagnosed with breast cancer. These women were compared for stage at diagnosis using multinomial logistic regression models. Cox proportional hazards regression models were used for breast cancer-specific mortality analyses. Comparisons were also performed according to implant characteristics. Results:Compared to women with other cosmetic surgery, those with cosmetic breast implants had later stage at breast cancer diagnosis (Odds Ratio of having stage III/IV vs stage I at diagnosis: 3.04, 95 % confidence interval (CI): 1.81 - 5.10; p < 0.001). A non-statistically significant increase in breast cancer-specific mortality rate for women with breast implants relative to surgical controls was observed (Hazard Ratio = 1.32, 95 % CI: 0.94-1.83, p = 0.11). No statistically significant differences in stage and breast cancer mortality were observed according to implant characteristics. Conclusions:At diagnosis, breast cancers tended to be at more advanced stages among women with cosmetic breast implants. Breast cancer specific survival was lower in these women although the reduction did not reach statistical significance. Impact:Further investigations of the effect of breast implants on breast cancer prognosis are warranted.