Risk factors for complications and implant loss after prepectoral implant-based immediate breast reconstruction: medium-term outcomes in a prospective cohort.

Background: Prepectoral implant-based breast reconstruction with acellular dermal matrix has become an increasingly popular option for selected patients. There are no randomized data to demonstrate short- or long-term outcomes. Cohort studies to date have demonstrated safety, but risk factors for complications are unknown.

Methods: A prospective cohort study of all patients undergoing prepectoral implant-based breast reconstruction between 2013 and 2019. Clinical factors and those related to reconstruction were analysed in relation to complications and implant loss using univariable and multivariable logistic regression.

Results: A total of 469 reconstructions were undertaken in 289 women; the majority of reconstructions were performed using a one-stage direct-to-implant technique with acellular dermal matrix. Median follow-up was 21 (range 2-71) months. Minor complications were seen after 11·2 per cent of reconstructions, major complications after 5·9 per cent, and the rate of implant loss by 3 months was 3·1 per cent. In the final multivariable model, sentinel node biopsy (odds ratio (OR) 5·06, 95 per cent c.i. 2·00 to 12·80), axillary clearance (OR 6·67, 1·17 to 37·94) and adjuvant radiotherapy (OR 7·11, 1·60 to 31·61) were independent risk factors for development of a major complication, and sentinel node biopsy (OR 4·32, 1·23 to 15·22) for implant loss.

Conclusion: Prepectoral implant-based breast reconstruction has acceptable medium-term results but careful patient selection is advised.