Postmenopausal Hormone Use and Risk of Large-Bowel Cancer

Abstract

Use of HRT was associated with a statistically significant reduced risk of colon cancer. In contrast, no statistically significant relationship was observed for rectal cancer. Given the widespread use of postmenopausal hormones and the morbidity and mortality from adenocarcinoma of the bowel in women, these findings may have potentially important public health implications.

Oral contraceptives, hormone replacement therapy and the risk of colorectal cancer

“…Interestingly, three other studies found an increased reduction in risk with more recent exposure (Jacobs et al, 1994;Calle et al, 1995;Newcomb and Storer, 1995). Other studies (Potter and McMichael, 1983 Although the present investigation is the largest casecontrol study to date published on this issue, the number of cases and controls exposed is limited.…”

“…Such an effect of female sex hormones on colorectal carcinogenesis is biologically plausible, as they influence hepatic cholesterol metabolism and bile production (McMichael and Potter, 1980), and steroid hormone receptors have been found in colorectal cancers and normal colonic mucosa (Singh et al, 1993; Hendrickse et al, 1993). Furthermore, an inverse relationship between parity and colorectal cancer risk (Potter and McMichael, 1983), as well as an increased incidence of colorectal cancer in nuns (Fraumeni et al, 1969), has been reported.Several cohort and case-control studies have investigated reproductive factors and colorectal cancer in women (La Vecchia and Franceschi, 1991;Potter et al, 1993) but only few have considered use of oral contraceptives and/or hormone replacement therapy (Potter and McMichael, 1983;Wu et al, 1987; Adami et al, 1989;Chute et al, 1991;Bostick et al, 1994;Weiss et al, 1981;Rosenberg et al, 1987; Davis et al, 1989;Furner et al, 1989;Peters et al, 1990; Kune et al, 1990;Wu-Williams et al, 1991; Gerhardsson de Verdier and London, 1992;Newcomb and Storer, 1995;Jacobs et al, 1994;Risch and Howe, 1995;Calle et al, 1995; Folsom et al, 1995). Among these, two studies have reported some (although inconsistent) increased risk of colorectal cancer among women who had used oral contraceptives (OCs) (Weiss et al, 1981; Kune et al, 1990), and one showed a moderate protection (Potter and McMichael, 1983).…”

“…Several cohort and case-control studies have investigated reproductive factors and colorectal cancer in women (La Vecchia and Franceschi, 1991;Potter et al, 1993) but only few have considered use of oral contraceptives and/or hormone replacement therapy (Potter and McMichael, 1983;Wu et al, 1987; Adami et al, 1989;Chute et al, 1991;Bostick et al, 1994;Weiss et al, 1981;Rosenberg et al, 1987; Davis et al, 1989;Furner et al, 1989;Peters et al, 1990; Kune et al, 1990;Wu-Williams et al, 1991; Gerhardsson de Verdier and London, 1992;Newcomb and Storer, 1995;Jacobs et al, 1994;Risch and Howe, 1995;Calle et al, 1995; Folsom et al, 1995). Among these, two studies have reported some (although inconsistent) increased risk of colorectal cancer among women who had used oral contraceptives (OCs) (Weiss et al, 1981; Kune et al, 1990), and one showed a moderate protection (Potter and McMichael, 1983).…”

“…Among these, two studies have reported some (although inconsistent) increased risk of colorectal cancer among women who had used oral contraceptives (OCs) (Weiss et al, 1981;Kune et al, 1990), and one showed a moderate protection (Potter and McMichael, 1983). In six studies an inverse relationship was observed for hormone replacement therapy (HRT) (Chute et al, 1991;Furner et al, 1989;Gerhardson de Verdier and London, 1992;Jacobs et al, 1994;Newcomb and Storer, 1995;Calle et al, 1995). In summary, most evidence suggests that OC and HRT use do not increase the risk of colorectal cancer, and some data even indicate a possible protective effect of HRT. Given the widespread use of OCs and HRT in developed countries, it is a major public health issue to further elucidate this relationship.…”

Downregulation of estrogen‐metabolizing 17β‐hydroxysteroid dehydrogenase Type 2 expression correlates inversely with Ki67 proliferation marker in colon‐cancer development

“…Prospective epidemiologic studies 6,51 have suggested that HRT is associated with a lower risk of colon cancer, with no difference in the protective effect from the regimen with estrogen alone or that in combination with progesterone. The mechanism of the protective effect is not clear; however, inhibition of cell proliferation by E1 has been described.…”