Post-Mastectomy Radiotherapy After Two-Stage Implant Breast Reconstruction: An Analysis of Long Term Outcomes in 2,326 Breast Implants Over 19 Years

Purpose

Post-mastectomy radiation (PMRT) has become increasingly indicated in patients with advanced breast cancer, and outcomes information is valuable for decision-making.^1-3 The objective of this study is to prospectively evaluate long-term outcomes in a large cohort of women who underwent immediate tissue expander/implant reconstruction.

Methods

A total of 3,982 tissue expander/implant reconstructions were performed in 2,718 patients by a single surgeon from 1992 to 2010.  A cohort of 1,557 patients was annually evaluated and patient/implant characteristics, PMRT and complications were prospectively recorded. Outcomes recorded included capsular contracture, rippling, post-exchange cellulitis, implant deflation, implant replacement, implant loss (implant removal without replacement), conversion to flap and aesthetic results. Complication rates were compared between the irradiated and non-irradiated group. Predictors for implant loss were evaluated with logistic regression. Predicted implant replacement and loss rates were examined by radiation status with Kaplan-Meier analysis and log-rank test.

Results

A total of 2,326 breast implant reconstructions with a minimum follow up of 1 year were included. Mean follow up was 57.2 months (range:12-200). Two-hundred ninety one patients received PMRT (12.5%). Severe capsular contracture grade 4 was present in 7.4% of irradiated and 0.6% of the non-irradiated (p<0.01), post-exchange cellulitis in 10.5% and 3.3%(p=0.01), implant replacement in 6.7% and 6.4% (p=NS) and implant loss in 9.1% and 0.7% respectively(p<0.01)(Figure 1). Deflation rates were similar between the groups. Seventy percent of irradiated patients had good to excellent aesthetic result, and 95% would choose implants again.

Predicted implant replacement rates at 10 years were similar between groups (p=NS). Predicted implant loss rates were higher for irradiated implants, 14.9% compared to 1.3% for non-irradiated(p<0.01)[Figure 2].

Multivariable analysis showed that greater body mass index (OR=1.09, p=0.04), post-exchange cellulitis (OR=32.1, p<0.01) and radiotherapy (OR=8.46, p<0.01) were predictors of implant loss.

Conclusion

This is the largest prospective evaluation of long-term outcomes in women with immediate tissue expander/implant breast reconstruction who underwent PMRT. Complication rates are higher for irradiated implants; however, most of the patients have a good to excellent aesthetic result and would choose implants again. Capsular contracture grade 3-4 is the most common complication and occurs in approximately half the irradiated implants.  Although radiation is a risk factor for implant removal, a vast majority of patients will preserve their reconstruction at 10 years.

Figure 1.

Figure 2.