Association of diabetes and diabetes treatment with incidence of breast cancer

作者：Garcia Esquinas Esther; Guino Elisabeth; Castano Vinyals Gemma; Perez Gomez Beatriz; Llorca Javier; Altzibar Jone M; Peiro Perez Rosana; Martin Vicente; Moreno Iribas Concepcion; Tardon Adonina; Javier Caballero Francisco; Puig Vives Montse; Guevara Marcela; Fernandez Villa Tania; Salas Dolores; Amiano Pilar; Dierssen Sotos Trinidad; Pastor Barriuso Roberto; Sala Maria; Kogevinas Manolis; Aragones Nuria; Moreno Victor; Pollan Marina^*

来源：Acta Diabetologica, 2016, 53(1): 99-107.

DOI：10.1007/s00592-015-0756-6

• Diabetes Mellitus
• Breast cancer
• Triple-negative breast neoplasms
• Metformin
• Insulin

The aim of this study was to evaluate the association of diabetes and diabetes treatment with risk of postmenopausal breast cancer.
Histologically confirmed incident cases of postmenopausal breast (N = 916) cancer were recruited from 23 Spanish public hospitals. Population-based controls (N = 1094) were randomly selected from primary care center lists within the catchment areas of the participant hospitals. ORs (95 % CI) were estimated using mixed-effects logistic regression models, using the recruitment center as a random effect term. Breast tumors were classified into hormone receptor positive (ER+ or PR+), HER2+ and triple negative (TN).
Diabetes was not associated with the overall risk of breast cancer (OR 1.09; 95 % CI 0.82-1.45), and it was only linked to the risk of developing TN tumors: Among 91 women with TN tumors, 18.7 % were diabetic, while the corresponding figure among controls was 9.9 % (OR 2.25; 95 % CI 1.22-4.15). Regarding treatment, results showed that insulin use was more prevalent among diabetic cases (2.5 %) as compared to diabetic controls (0.7 %); OR 2.98; 95 % CI 1.26-7.01. They also showed that, among diabetics, the risk of developing HR+/HER2- tumors decreased with longer metformin use (ORper year 0.89; 95 % CI 0.81-0.99; based on 24 cases and 43 controls).
This study reinforces the need to correctly classify breast cancers when studying their association with diabetes. Given the low survival rates in women diagnosed with TN breast tumors and the potential impact of diabetes control on breast cancer prevention, more studies are needed to better characterize this association.

• 出版日期2016-2