METHODS: We used pooled data on tumor markers (estrogen and progesterone receptor, human epidermal growth factor receptor-2 (HER2)) and reproductive risk factors (parity, age at first full-time pregnancy (FFTP) and age at menarche) from 28,095 patients with invasive BC from 34 studies participating in the Breast Cancer Association Consortium (BCAC). In a case-only analysis, we used logistic regression to assess associations between reproductive factors and BC subtype compared to luminal A tumors as a reference. The interaction between age and parity in BC subtype risk was also tested, across all ages and, because age was modeled non-linearly, specifically at ages 35, 55 and 75 years.
RESULTS: Parous women were more likely to be diagnosed with triple negative BC (TNBC) than with luminal A BC, irrespective of age (OR for parity = 1.38, 95% CI 1.16-1.65, p = 0.0004; p for interaction with age = 0.076). Parous women were also more likely to be diagnosed with luminal and non-luminal HER2-like BCs and this effect was slightly more pronounced at an early age (p for interaction with age = 0.037 and 0.030, respectively). For instance, women diagnosed at age 35 were 1.48 (CI 1.01-2.16) more likely to have luminal HER2-like BC than luminal A BC, while this association was not significant at age 75 (OR = 0.72, CI 0.45-1.14). While age at menarche was not significantly associated with BC subtype, increasing age at FFTP was non-linearly associated with TNBC relative to luminal A BC. An age at FFTP of 25 versus 20 years lowered the risk for TNBC (OR = 0.78, CI 0.70-0.88, p
METHODS: A cross-sectional survey was conducted at the four outpatient clinics of general hospitals in Tehran during the period from July through October, 2009. Bi-variate analyses and multi-variate binary logistic regression were employed to find the socio- demographic predictors of mammography utilization among participants.
RESULTS: The rate of mammography participation was 21.5% and relatively high because of access to general hospital services. More women who had undergone mammography were graduates from university or college, had full-time or part-time employment, were insured whether public or private, reported a positive family history of breast cancer, and were in the middle income level (P <0.01).The largest number of participating women was in the age range of 41 to 50 years. The results of multivariate logistic regression further showed that education (95%CI: 0.131-0.622), monthly income (95%CI: 0.038-0.945), and family history of breast cancer (95%CI: 1.97-9.28) were significantly associated (all P <0.05)with mammography participation.
CONCLUSIONS: The most important issue for a successful screening program is participation. Using a random sample, this study found that the potential predictor variables of mammography participation included a higher education level, a middle income level, and a positive family history of breast cancer for Iranian women after adjusting for all other demographic variables in the model.