Impact of diabetes on surgery and radiotherapy for breast cancer

Abstract

Purposes This study aims to examine whether diabetes has an impact on the use of surgery and adjuvant radiotherapy in treating women with localised breast cancer. Methods Women diagnosed with stage I–III breast cancer between 2005 and 2020 were identified from Te Rēhita Mate Ūtaetae—Breast Cancer Foundation New Zealand National Register, with diabetes status determined using New Zealand’s Virtual Diabetes Register. The cancer treatments examined included breast conserving surgery (BCS), mastectomy, breast reconstruction after mastectomy, and adjuvant radiotherapy after BCS. Logistic regression modelling was used to estimate the adjusted odds ratio (OR) and 95% confidence interval (95% CI) of having cancer treatment and treatment delay (> 31 days) for patients with diabetes at the time of cancer diagnosis compared to patients without diabetes. Results We identified 25,557 women diagnosed with stage I–III breast cancer in 2005–2020, including 2906 (11.4%) with diabetes. After adjustment for other factors, there was no significant difference overall in risk of women with diabetes having no surgery (OR 1.12, 95% CI 0.94–1.33), although for patients with stage I disease not having surgery was more likely (OR 1.45, 95% CI 1.05–2.00) in the diabetes group. Patients with diabetes were more likely to have their surgery delayed (adjusted OR of 1.16, 95% CI 1.05–1.27) and less likely to have reconstruction after mastectomy compared to the non-diabetes group—adjusted OR 0.54 (95% CI 0.35–0.84) for stage I cancer, 0.50 (95% CI 0.34–0.75) for stage II and 0.48 (95% CI 0.24–1.00) for stage III cancer. Conclusions Diabetes is associated with a lower likelihood of receiving surgery and a greater delay to surgery. Women with diabetes are also less likely to have breast reconstruction after mastectomy. These differences need to be taken in to account when considering factors that may impact on the outcomes of women with diabetes especially for Māori, Pacific and Asian women.

Does diabetes affect breast cancer survival?

“…Additionally, diabetes is associated with prolonged surgical delays, as indicated by an OR of 1.16 (95% CI: 1.05-1.27). 2 We also found that women with diabetes were less likely to have chemotherapy, but that women with diabetes were more likely to receive endocrine therapy for stage III disease and had better adherence to endocrine therapy. 13,14 The impact of diabetes on survival in people with breast cancer has not been examined in Aotearoa/New Zealand, and findings from international studies are controversial.…”

“…Additionally, it contributes to prolonged delays in surgery for breast cancer patients. 2 Women with diabetes were also undertreated with chemotherapy, 28 but had better adherence to endocrine therapy than women without diabetes. 13,14 Nevertheless, this study indicates that despite observed treatment disparities between women with diabetes and those without, these differences did not translate into discernible disparities in breast cancer survival after adjustments for age and cancer stage.…”

Preexisting Diabetes and Breast Cancer Treatment Among Low-Income Women

“…In a population-based study in New Zealand, women with diabetes with breast cancer had lower odds of radiotherapy following lumpectomy compared with counterparts without diabetes. 40 This difference was not significant after adjustment for comorbidity scores in addition to demographic The analysis of radiation therapy was restricted to patients undergoing breast-conserving surgery and node-positive patients undergoing mastectomy. Chemotherapy was analyzed in patients with nodepositive tumors and patients with hormone receptornegative tumors or hormone receptor-positive and ERBB2-positive tumors.…”

In hospital outcomes of autologous and implant‐based breast reconstruction in patients with diabetes mellitus: A population‐based study of 2015–2020 national inpatient sample

“…17 DM is linked to a reduced likelihood of undergoing mastectomy and a lower probability of receiving breast reconstruction postmastectomy. 18 Patients of older age, greater obesity, and higher comorbidity burden had a reduced likelihood of undergoing breast reconstruction. 18 These preoperative differences were observed in the DM patients in this study and may contribute to their lower rates of breast reconstruction.…”

“…18 Patients of older age, greater obesity, and higher comorbidity burden had a reduced likelihood of undergoing breast reconstruction. 18 These preoperative differences were observed in the DM patients in this study and may contribute to their lower rates of breast reconstruction.…”