Risk of lymphoma in women with breast implants: Analysis of clinical studies.

Abstract

1588 Background: Large studies suggest the overall rate of lymphoma in women with breast implants is no greater than in the general population although recent clinical reports suggest a potential association between breast implants and the rare non-Hodgkin lymphoma: anaplastic large cell lymphoma (ALCL) of the breast. Methods: Observed cases of lymphoma reported in Allergan-sponsored breast implant clinical studies were compared to the numbers of cases expected based on incidence rates of lymphoma among women in the National Cancer Institute’s Surveillance Epidemiology and End Results (SEER) program, using standardized incidence ratios (SIRs) and 95% confidence intervals (CIs). Results: In these clinical studies, a combined total of 28 observed cases of lymphoma were reported among 89,382 patients with 204,682 person-years of follow-up compared with 43 expected cases [SIR==0·65 (95% CI: 0·43-0·94) P==0·02]. SIRs were calculated stratifying by baseline cancer history: the risk was not significantly elevated either among women without a prior history of cancer [SIR ==0·70 (95% CI: 0·41-1·13) P==0·17], or women with a prior cancer history [SIR==0·79 (95% CI: 0·39-1·41) P==0·52]. SIRs were calculated by implant shell type and, again, there was no evidence of an increased risk either for textured shell implants [SIR==0·70 (95% CI: 0·40-1·13) P==0·16] or smooth shell implants [SIR==0·63 (95% CI: 0·33-1·10) P==0·12]. SEER reported 12 cases of primary breast ALCL in women between 1996-2007 without a previous history of cancer, producing an average annual incidence of 4·28 (95% CI: 3·51-5·05) per 100 million women in the United States – these women may or may not have had breast implants. In clinical studies, three ALCL cases were reported in women with breast implants and a history of breast cancer, yielding a crude incidence rate of 1·46 (95% CI: 0·30-4·3) per 100,000 patient-years. Conclusions: Large, carefully conducted clinical studies, based on over 89,000 subjects with over 200,000 person-years of follow-up, suggest no evidence of an increased risk of lymphoma among women who have received breast implants.