Caracterización y recaídas de la reconstrucción postmastectomía en el contexto de la radioterapia adyuvante en el tratamiento del carcinoma de mama

Abstract

Introduction: Up to a third of patients with breast cancer require mastectomy, after which postmastectomy reconstruction (PMR) is usually offered. A subgroup of patients will require the administration of postoperative radiotherapy to the chest wall (PMRT), as a benefit in disease-free and overall survival has been demonstrated. The choice of the PMR technique and when to perform it are controversial due to the eventual post-surgical complications involved in irradiating the reconstructed chest wall. Currently, there is no type I evidence available on what is the best reconstruction, sequence, or acceptable time between one procedure and another when it is performed differently, so it continues to be an institution-dependent management. Objectives: To determine the possible relationship between the appearance of complications with and without PMRT after RPM, in terms of: 1) specific morbidity; 2) breast cancer recurrence rate; 3) morbidity depending on the moment of RPM (immediate vs. delayed); 4) morbidity depending on the reconstruction technique (autologous vs. heterologous) and 5) systemic treatment, hormone therapy, volume of the prosthesis and target volumes of radiotherapy. Material and Methods: Observational, retrospective and single-center clinical study, based on the analysis of a database of 273 patients diagnosed with breast carcinoma treated by mastectomy and exclusive reconstruction or with associated adjuvant radiotherapy, between the years 2016 and 2020. at the Virgen de la Arrixaca University Clinical Hospital in Murcia, and with a minimum follow-up period of two years. A descriptive and comparative study was carried out between the groups with and without PMRT with respect to a series of variables (demographic, anatomopathological, treatment and follow-up), and statistical analysis was carried out. Results: After a median follow-up of 65 months, 42.1% of the cases developed some type of associated morbidity, with no differences between those who received RTPM and those who did not (62.6% vs 37.4%, p=0.146). Among the complications, 55,7% were reconstructed by immediate PMR, 23,5% delayed, and 20,9% immediate-delayed (p=0.027). Regarding complications according to technique, autologous PMR was performed in 27% and heterologous in 73% (p<0.001). 59.6% relapsed at different levels, observing a trend towards statistical significance in favor of PMRT (p=0.063). The median survival was 44.50 months and 35 months (PMRT and no PMRT, respectively, p=0.809). No correlation was found between the incidence of complications and PMRT according to the administration of chemotherapy, hormone therapy or addition of axillo- supraclavicular lymph node volumes, although it was found with prosthetic volumes equal to or greater than 300cc (p=0.057). Conclusions: No specific correlation has been found between the administration of PMRT and complications after PMR. However, a significant increase in them has been observed in heterologous reconstructions and in those performed immediately. A worse evolution has also been observed when the prosthetic volumes are greater than 300cc, although not when the radiotherapy volumes include the lymph node areas, in addition to the mastectomy bed.