The Role of pre-mastectomy sentinel node biopsy in the managment of immediate reconstruction in breast cancer patients: a cohort study

Abstract

Background: Post-mastectomy radiation therapy (PMRT) typically poses a contraindication for immediate breast reconstruction (IBR). Sentinel lymph node biopsy (SLNB) becomes imperative to identify candidates more effectively for delayed breast reconstruction (DBR). This study aimed to assess the impact of an independent SLNB prior to mastectomy in determining the need for PMRT. Methods: We conducted a retrospective analysis of patients who underwent primary SLNB followed by mastectomy at the Breast Centre of Unidade Local de Saúde São João from January 1st, 2011, to December 31st, 2020. Results: In the analysis of 339 patients, 223 (69.9%) showed a negative SLNB result, and all of them proceeded with IBR. Within the pN+sn group, 23.9% (23/96) ultimately underwent IBR. Despite being pN0sn, 3.6% (8/223) were proposed to receive PMRT; on the contrary, 42.7% (41/96) of the pN+sn patients were spared from it. In total, 15.4% of the cases were approached differently than planned. Conclusions: A noteworthy 76% of the pN+sn patients had their IBR plan changed. Despite the clinical relevance of primary SLNB appearing very low, since in our sample of patients this information was disregarded in 43% of cases, it provides essential information for deciding on the timing of breast reconstruction. Key words: Breast Neoplasms, Sentinel Lymph Node, Mastectomy, Mammaplasty, Radiotherapy.