The incidence and survival of breast cancer (BC) vary across countries. This study aimed to determine risk factors for BC and estimate the overall survival rate in BC patients of the Golestan Cohort Study (GCS).
Methods
This case-control study was performed among participants of the GCS. Cases (N = 99) consisted of women who were diagnosed with BC and controls (n = 400) were selected out of women participating in the same cohort and had not developed any cancer during the follow-up period. Controls were frequency matched to case on both place of residency and 5-year categories of age.
Results
Considering confounding variables, logistic regression analysis manifested a reverse association between parity and BC (OR [odds ratio] = 0.87, 95% CI: 0.80-0.95, P = 0.001). In addition, we found women who had family history of any cancer (OR = 1.63, 95% CI: 1.02-2.60, P = 0.04) and long term oral contraceptive (OCP) use (≥10 years) (OR = 3.17, 95% CI: 1.27-7.95, P = 0.01) were at higher risk of BC. Of the total patients, 23 (23.2%) were died due to BC after a mean follow-up of 102.4 ± 5.31 months. Using the Kaplan-Meier analysis, the 5-year survival in these patients was 74%.
Conclusion
In the Golestan Cohort population, long term OCP use and family history of cancer were risk factors for BC, while parity was a protective factor. The 5-year survival of BC patients in the GCS is still lower relative to Europe and the United States.
oral contraceptive long-term use breast cancer risk Iran, parity protective factor breast cancer case-control study, Golestan cohort study breast cancer risk factors Iran, OCP use ten years breast cancer odds ratio, family history cancer breast cancer risk factor, breast cancer survival rate developing countries Iran, oral contraceptive pill breast cancer case-control study, parity inverse association breast cancer risk, breast cancer incidence survival Golestan population-based, Alipour Malekzadeh breast cancer risk factors cohort
Cite this article
Alipour, S., omranipour, R., Malekzadeh, R., Poustchi, H., Pourshams, A., khoshnia, M., Gharavi, A., Roshandel, G., & Eslami, B. (2019). A Case-Control Study of Breast Cancer in Northeast of Iran: The Golestan Cohort Study. Archives of Iranian medicine, 22(7), 355-360.
Alipour S, omranipour R, Malekzadeh R, Poustchi H, Pourshams A, khoshnia M, et al. A Case-Control Study of Breast Cancer in Northeast of Iran: The Golestan Cohort Study. Arch Iran Med. 2019;22(7):355-360.
Alipour, Sadaf, et al. "A Case-Control Study of Breast Cancer in Northeast of Iran: The Golestan Cohort Study." Archives of Iranian medicine, vol. 22, no. 7, 2019, pp. 355-360.
Keywords
Contraceptives, Oral
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