Menstrual and Reproductive Factors and Risk of Gastric and Colorectal Cancer in Spain.

oleh: Virginia Lope, Nerea Fernández de Larrea, Beatriz Pérez-Gómez, Vicente Martín, Victor Moreno, Laura Costas, Federico Longo, José Juan Jiménez-Moleón, Javier Llorca, Nieves Ascunce, Rosana Peiró-Pérez, Jone M Altzibar, Adonina Tardón, Juan Alguacil, Carmen Navarro, Ángeles Sierra, Ana Belén Vega, Amaya Villafañe, Gemma Castaño-Vinyals, Manolis Kogevinas, Marina Pollán, Nuria Aragonés

Format: Article
Diterbitkan: Public Library of Science (PLoS) 2016-01-01

Deskripsi

Sex hormones play a role in gastric cancer and colorectal cancer etiology, however, epidemiological evidence is inconsistent. This study examines the influence of menstrual and reproductive factors over the risk of both tumors.In this case-control study 128 women with gastric cancer and 1293 controls, as well as 562 female and colorectal cancer cases and 1605 controls were recruited in 9 and 11 Spanish provinces, respectively. Population controls were frequency matched to cases by age and province. Demographic and reproductive data were directly surveyed by trained staff. The association with gastric, colon and rectal cancer was assessed using logistic and multinomial mixed regression models.Our results show an inverse association of age at first birth with gastric cancer risk (five-year trend: OR = 0.69; p-value = 0.006). Ever users of hormonal contraception presented a decreased risk of gastric (OR = 0.42; 95%CI = 0.26-0.69), colon (OR = 0.64; 95%CI = 0.48-0.86) and rectal cancer (OR = 0.61; 95%CI = 0.43-0.88). Postmenopausal women who used hormone replacement therapy showed a decreased risk of colon and rectal tumors. A significant interaction of educational level with parity and months of first child lactation was also observed.These findings suggest a protective role of exogenous hormones in gastric and colorectal cancer risk. The role of endogenous hormones remains unclear.