Adherence to a western dietary pattern and risk of invasive ductal and lobular breast carcinomas: a case-control study.

Little is known about the role of diet in the risk of invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC) of the breast, the most common histological subtypes of breast cancer (BC). This is because, the majority of studies on the association of diet and the risk of BC are focused on single food items, and studies considering the overall diet in terms of dietary patterns are limited. Also, the potential heterogeneity in the impact of Western diet (WD) on histological subtypes of BC is not established. This, the age-frequency-matched case-control study included 1009 incident BC cases and 1009 healthy controls. The required data was obtained from the patients' medical files and interviews using a previously validated researcher-designed questionnaire for collecting data on socio-economic and anthropometric statuses and a valid food frequency questionnaire (FFQ) to measure the participants' dietary intake. We used multinomial logistic regression, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. A positive and significant association was observed between higher adherence to a WD and risk of IDC (OR comparing highest with the lowest tertile: 2.45, 95% CI 1.88, 3.17; p-trend < 0.001), whereas no significant association was observed between adherence to the WD and the risk of ILC (OR comparing highest with the lowest tertile: 1.63, 95% CI 0.63, 3.25) (p for heterogeneity = 0.03). The results of an analysis stratified by menopausal status suggested a similar pattern. We provided evidence that adherence to a WD raises the risk of IDC, but not ILC, suggesting different etiological mechanisms for IDC and ILC.

Determinants of delay in diagnosis and end stage at presentation among breast cancer patients in Iran: a multi-center study.

One of the reasons for high mortality of breast cancer (BC) is long delay in seeking medical care and end stage at presentation. This study was designed to measure the association between a wide range of socio-demographic and clinical factors with diagnostic delay in BC and stage at presentation among Iranian patients. From June 2017 to December 2019, 725 patients with newly diagnosed BC in Shiraz and Kermanshah were selected and information on BC diagnosis delay was obtained from the patient's medical record. Data on socio-economic status was obtained via a structured interview. Our findings suggest that 45.8% of the patients were diagnosed at a late stage (stage 3 or higher). A total of 244 (34%) patients had more than 3 months delay in diagnosis. We found a significant association between stage at diagnosis and place of residence (adjusted odds ratio (aOR rural vs. urban = 1.69, 95% CI 1.49-1.97), marital status (aOR 1.61, 95% CI 1.42-1.88), family history of BC (aOR 1.46, 95% CI 1.01-2.13), and history of benign breast disease (BBD) (aOR 1.94, 95% CI 1.39-2.72) or unaware of breast self-examination (BSE) (aOR 1.42, 95% CI 1.42-1.85), delay time (aOR 3.25, 95% CI 1.04-5.21), and left breast tumor (aOR right vs. left 2.64, 95% CI 1.88-3.71) and smoking (aOR no vs. yes 1.59, 95% CI 1.36-1.97). Also, delay in diagnosis was associated with age, family income, health insurance, place of residence, marital status, menopausal status, history of BBD, awareness of breast self-examination, type of first symptoms, tumor histology type, BMI and comorbidity (p < 0.05 for all). Factors including history of BBD, awareness of BSE, and suffering from chronic diseases were factors associated with both delay in diagnosis and end stage of disease. These mainly modifiable factors are associated with the progression of the disease.