Variability of breast surgery in women participating in breast cancer screening programs

Introduction: Currently, variability in surgical practice is a problem to be solved. The aim of this study is to describe the variability in the surgical treatment of breast cancer and to analyze the factors associated with it. Methods: The study population included 1057 women diagnosed with breast cancer and surgically treated. Our data were from the CaMISS retrospective cohort. Results: The mean age at diagnosis was 59.3 ± 5 years. A total of 732 patients were diagnosed through screening mammograms and 325 patients as interval cancers. The mastectomy surgery was more frequent in the tumors detected between intervals (OR = 2.5; [95%CI: 1.8-3.4]), although this effect disappeared when we adjusted for the rest of the variables. The most important factor associated with performing a mastectomy was TNM: tumors in stage III-IV had an OR of 7.4 [95%CI: 3.9-13.8], increasing in adjusted OR to 21.7 [95%CI: 11.4-41.8]. Histologically, infiltrating lobular carcinoma maintains significance in adjusted OR (OR = 2.5; [95%CI: 1.4-4.7]). According to the screening program, there were significant differences in surgical treatment. Program 3 presented an OR of non-conservative surgery of 4.0 [95%CI: 1.8-8.9]. This program coincided with the highest percentage of reconstruction (58.3%). Conclusions: This study shows that, despite taking into account patient and tumor characteristics, there is great variability in the type of surgery depending on the place of diagnosis.