The Association of Reproductive and Menstrual Factors and Oral Contraceptive Usage with Colon Cancer; "A Case-Control Study in North East of Iran"

Document Type : Original Article

Authors

1 Assistant Prof., Department of Internal Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Resident, Department of Nuclear Medicine, Faculty of Medicine, Mashhad University of Medical Science, Mashhad, Iran.

3 Assistant Prof., Department of Community Medicine, Faculty of Medicine, Mashhad University of Medical Science, Mashhad, Iran.

Abstract

Introduction: Colon cancer is one of the cancers which are strongly influenced by environmental factors. In 1980, "feminine sex hormones" were suggested as factors that might be related with colon cancer and many studies have been performed since then. The present case-control study investigated the correlation of menstrual, reproductive and oral contraceptive (OCP) factors with colon cancer in women older than 45 years old who had colon cancer.
 
Methods: This case-control study was conducted in two major hospitals of Mashhad. It enrolled 83 women with colon cancer in the study group and 99 women who were admitted to Ghaem and Imam Reza hospitals for the conditions unrelated to gastrointestinal and gynecological diseases in the control group. The median age of the participants was at least 45 years old.
 
Factors such as parity, age at first full-term pregnancy, number of abortions, age at menopause and duration of OCP usage (in years) were compared between the two groups.
 
Results: There was a significant trend of decreasing colon cancer risk with increased parity (p=0.01). Age at first pregnancy was directly associated with the risk of development of colon cancer (p<0.01). There was no significant difference in number of abortions between those two groups of our study. (p>0.1) Also there was no significant correlation of the age at menopause of older than 50 years and OCP usage with the risk of development of colon cancer (p>0.1, p>0.1, respectively).
 
Conclusion: Based on the findings of the present study, it seems that the relationship between reproductive factors and colon cancer is more prominent than menstrual factors and OCP usage, but verification or rejection of this conclusion needs stronger and more consistent evidences.
 
 

Keywords


1. Robert JM. Gastrointestinal tract cancer. In: Dennis LK, Anthony SF, Dan LL, Eugene B,
Stephen LH, Larry JJ, editors. Harrison’s principles of internal medicine. 16th
ed. New York:
McGraw-Hill Professional; 2005. p.523-33.
2. Robert SB. Malignant neoplasms of the large intestine. In: Lawrence SF, Marvin HS, Mark F,
editors. Sleisenger & Fordtran’s gastrointestinal and liver disease. 7th
ed. Pennsylvania: The
Curtis Center; 2002. p. 2215-56.
3. Nichols HB, Trentham-Dietz A, Hampton JM, Newcomb PA. Oral contraceptive use,
reproductive factors, and colorectal cancer risk: findings from Wisconsin. Canser Epidemiol
Biomarkers Prev 2005;14(5):1212-8.
4. MC Michael AJ, Potter JD. Reproduction, endogenous and exogenous sex hormones and colon
cancer: a review and hypothesis. J Natl cancer Inst 1980;65:1201-7.
5. Wolf LA, Terry PD, Potter JD, Bostick RM. Do factors related to endogenous and exogenous
modify the relationship between obesity and risk of colorectal adenomas in women? Cancer
Epidemiol Biomarkers Prev 2007;16(4):676-83.
6. Tamakoshi K, Wakai K, Kojima M, Watanabe Y, Hayakawa N, Toyoshima H, et al. A
prospective study of reproductive and menstrual factors and colon cancer risk in Japanese
women. Cancer Sci 2004;95(7):602-7. 
 
7. Lin J, Zhang SM, Cook NR, Manson JE, Buring JE, Lee IM. Oral contraceptives, reproductive
factors, and risk of colorectal cancer among women in a prospective cohort study. Am J
Epidemiol 2007;165(7):794-801.
8. Fraumeni JF, Lioyd JW, Smith EM, Wagoner JK. Cancer mortality among nuns: Role of marital
status in etiology of neoplastic disease in women. J Natl Cancer Inst 1996;42(3):455-67.
9. Slattery ML, Potter JD, Curtin K, et al. Estrogens reduce and withdrawal of estrogens increase
risk of microsatellite instability-positive colon cancer. Cancer Res 2001;61(1):126-30.
10. Tokudome S, Hashimoto S, Suzuki K, Ito Y, Tamakoshi A. A prospective study on the possible
association between having children and colon cancer risk. Cancer Sci 2004;95(3):243-7.
11. Olsson H, Bladstrom A, Ingyar C. Are smoking-associated cancers prevented or postponed in
women using hormone replacement therapy? Obstet Gynecol 2003;102(3):565-70.
12. Slattery ML, Samowitz WS, Holden JA. Estrogen and progesterone receptors in colon tumors.
Am J Clin Pathol 2000;113(3):364-8.
13. Rosenblatt KA, Gao DL, Ray RM, Nelson ZC, Thomas DB. Contraceptive methods and induced
abortions and their association with the risk of colon cancer in Shanghai, China Eur J Cancer
2004;40(4):590-3.
14. Martinez ME, Grodstein F, Giovannucci E, Colditz GA, Speizer FE. A prospective study of
reproductive factors, oral contraceptive use, and risk of colorectal cancer. Cancer Epidemiol
Biomarkers Prev 1997;6(1):1-5.