Abstract PS1-05: Trends in breast-conserving surgery in Mexico after the implementation of a public health insurance system
Authors: Bargalló-Rocha Enrique , Reynoso-Noveron Nancy , Corona Jaime , Esparza-Arias Nereida , Ramírez-Ugalde María Teresa , Robles-Vidal Caros Daniel , Shaw-Dulin Robin , Stankov Armen , Vazquez-Romo Rafael , Villarreal-Colin Patricia , Aguilar-Villanueva Sergio , Hidalgo-Bahena Jaime , Perez-Quintanilla Milagros , Lara-Medina Fernando U , Torres Juan Alejandro , Soto-Perez-de-Celis Enrique , Cabrera-Galeana Paula , Mohar Alejandro , Meneses-García Abelardo 
Published: February 2021

Abstract
Introduction Although temporal trends in breast conserving surgery (BCS) have been described for developed countries like the United States (US), there is a lack of information regarding the uptake of breast conservation in developing regions of the world. In developing countries, the implementation of breast conservation might be hindered by the availability of radiation therapy, lack of training among surgeons, or concerns regarding compliance with follow-up care and surveillance. In 2006, the Mexican government created Seguro Popular, which provided coverage for breast cancer care for all Mexican women, thus potentially mitigating the difficulties with obtaining care after BCS and improving access to multidisciplinary care. We undertook an overview of ten years of breast cancer surgery at our Mexican cancer center following the implementation of Seguro Popular, and explored changes in surgical technique over time. Methods A retrospective cohort analysis was conducted using the National Cancer Institute of Mexico (INCAN) database from 2006 to 2016. All patients with a diagnosis of breast cancer seen during that period were included. Patients who received surgery for breast cancer where then grouped together based on the type of surgery (mastectomy versus BCS). The effect of the year of diagnosis and of clinical stage at the time of presentation was evaluated. Logistic regression was used to model temporal trends in use of BCS over mastectomy for three 3-year periods (2006-2009, 2010-2012, and 2013-2016). Results The patient cohort consisted of 5289 women from the INCAN database, of which 4519 received some form of local surgical treatment. Sixty-one percent (n = 2764) had locally advanced disease (stages IIB-IIIC) at the time of presentation, and a quarter (n = 1156) had ≥60 days between diagnosis and receipt of surgical treatment. Eighty percent of the patients in the entire cohort (n = 3611) were treated with mastectomy, while 20% (n = 908) received BCS. For the 2006-2009 period, out of 1596 total surgeries, 9.9% were BCS (n = 158). The proportion of BCS increased for each of the other two studied periods, being 18.5% for the 2010-2012 period (n = 276/1490), and 33.1% for the 2013-2016 period (n = 474/1433) (p&lt;0.01 for trend). While the increase in BCS was significant for all stages, it was most pronounced for women with early-stage disease (Stages I-IIA), going from 17% in 2006-2009 to 52% in 2013-2016 (p&lt;0.01), than in those with locally-advanced disease (6.5 to 18%, p&lt;0.01). Conclusions In the ten years after the start of the Seguro Popular public insurance program, the proportion of BCS at a Mexican cancer center increased significantly, particularly for women with early-stage disease. The rates seen at INCAN for the period between 2013-2106 resemble those reported by the US National Cancer Database, in which approximately 61% of women with stage I-II breast cancer and 20% of women with stage III disease receive BCS. Potential reasons for the increase in the uptake of BCS include improved access to adjuvant radiation therapy, improved access to systemic treatment, and higher adherence to follow-up care after the start of Seguro Popular, as well as improvements in surgical training. In addition, changes in BCS may also be related to improvements in the implementation of multidisciplinary teams over time, which may lead to a more homogeneous and comprehensive care. Our results show that improving access to care for patients living in developing countries positively impacts the uptake of BCS for women with breast cancer.
Citation Format: Enrique Bargalló-Rocha, Nancy Reynoso-Noveron, Jaime Corona, Nereida Esparza-Arias, María Teresa Ramírez-Ugalde, Caros Daniel Robles-Vidal, Robin Shaw-Dulin, Armen Stankov, Rafael Vazquez-Romo, Patricia Villarreal-Colin, Sergio Aguilar-Villanueva, Jaime Hidalgo-Bahena, Milagros Perez-Quintanilla, Fernando U Lara-Medina, Juan Alejandro Torres, Enrique Soto-Perez-de-Celis, Paula Cabrera-Galeana, Alejandro Mohar, Abelardo Meneses-García. Trends in breast-conserving surgery in Mexico after the implementation of a public health insurance system [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-05.