Menstrual and reproductive factors in relation to ovarian cancer risk

Abstract

The reduced risk of epithelial ovarian cancer associated with parity and oral contraceptive use suggests that pituitary and/or ovarian hormones or ovulatory events are important in the aetiology of these tumours (Cramer, 1986). Nevertheless, despite extensive study, the influence of menstrual and reproductive factors, with the exception of parity, remains uncertain. In this report, we evaluate menstrual and reproductive characteristics in relation to ovarian cancer risk overall, and in relation to the major tumour histologic subtypes. Our findings are considered in light of several current hypotheses regarding ovarian cancer pathogenesis. Briefly, the incessant ovulation hypothesis suggests that risk is increased by chronic post-ovulatory trauma to the epithelial surface of the ovary, and the tendency to form inclusion cysts (Fathalla, 1971;Casagrande et al, 1979). The gonadotrophin hypothesis proposes that excessive gonadotropin secretion and consequent increases in oestrogen stimulation lead to proliferation and malignant transformation of ovarian epithelium . More recent hypotheses have suggested a role for chronic ovarian inflammation (Ness, 1999), androgens and progesterone (Risch, 1998), and the possibility that pregnancies reduce risk by clearing transforming cells from the ovaries (ovarian clearance) (Adami et al, 1994). METHODSWe conducted a population-based, case-control study of epithelial ovarian cancer in eastern Massachusetts (MA) and New Hampshire (NH). The methods used have been previously described Harlow et al, 1998). Briefly, 1033 potentially eligible case women (ages 20 to 74) were ascertained between May 1992 and March 1997 through state-wide cancer registries (NH, MA) and hospital tumour boards (MA). After exclusion of patients who had nonepithelial tumours (n = 52), and those who had died (n = 91), moved out of state (n = 27), had no telephone (n = 24), or did not speak English (n = 14), 825 case women were eligible for the study. Physicians denied permission to contact 126 (14%) of these women, and 136 (16%) of women declined to participate. This analysis is based on 563 cases of epithelial ovarian cancer, including lesions of borderline malignancy.Control women were identified primarily by random digit dialing (RDD) (Waksberg, 1978), and matched to case women by age (within 4 years) and telephone sampling unit. Of approximately 5400 residential households contacted, 10% declined to provide a household census, and 80% provided a census, but lacked a potentially eligible control subject. In the remaining 10% of households, a potentially eligible control was identified. 72% of the potential control women agreed to participate in the study. In MA, control women of age 60 or older were randomly chosen from Town Books, and matched to case women by age and precinct. Of 328 control women selected from Town Books, 21% Summary We assessed menstrual and reproductive factors in relation to ovarian cancer risk in a large, population-based, case-control study. 563 cases in Massachusetts and New Hampsh...

Prevalence of ovarian tumours among ovarian mass lesions in Gajra Raja Medical College, Gwalior, India

“…16 In another population based case control study, Ernstaff T et al found that risk of ovarian tumors was higher in multiparous, a woman which is comparable to results of present study. 17 In current study, 54.6% presented with ovarian tumor after 1 year of development of symptoms reason of delay were non-specific symptoms, inadequate health care system, omission of pelvic examination at presentation, illiteracy and poverty. Muhabat Q studied 43% patients were presented with ovarian tumour after >1 year of symptoms.…”

Twin births, sex of children and maternal risk of ovarian cancer: a cohort study in Norway

“…Previous studies have found a lower or rather similar risk of epithelial ovarian cancer in twin compared to singleton mothers (Olsen and Storm, 1998;Lambe et al, 1999;Whiteman et al, 2000;Titus-Ernstoff et al, 2001;Neale et al, 2004Neale et al, , 2005, but few have focused on sex of the twins, or performed subgroup analyses. One study based on pooled data from eight case -control studies (Whiteman et al, 2000) found an adverse effect of twinning in relation to mucinous tumours, but a protective effect in relation to non-mucinous tumours.…”

“…Women prone to have multiple births have a higher level of follicle-stimulating hormone (Bulmer, 1970;Corney et al, 1981;Risch, 1998) and may also ovulate more often (Allen, 1981), possibly leading to an increased risk (Risch, 1998;Lukanova and Kaaks, 2005). Certain maternal or pregnancy-related factors associated with twinning may however be related to a reduced risk (Risch, 1998) though only a slightly lower or similar risk has been reported in twin compared to singleton mothers (Wyshak et al, 1983;Olsen and Storm, 1998;Lambe et al, 1999;Whiteman et al, 2000;Titus-Ernstoff et al, 2001;Neale et al, 2004Neale et al, , 2005.Hormones may play a role in ovarian cancer carcinogenesis (Riman et al, 1998;Risch, 1998;Lukanova and Kaaks, 2005). Maternal hormone levels have been found to be higher in pregnancies involving twins (TambyRaya and Ratnam, 1981;Risch, 1998;Storgaard et al, 2006).…”

Progesterone receptor variation and risk of ovarian cancer is limited to the invasive endometrioid subtype: results from the ovarian cancer association consortium pooled analysis

“…The protective effect increases steadily with each birth and pregnancy is associated with high progesterone levels (Hartge et al, 1989;Cooper et al, 1999;Titus-Ernstoff et al, 2001;Whiteman et al, 2003;Pike et al, 2004). In the third trimester, progesterone levels are some 10 -15 times higher than in the luteal phase of the normal menstrual cycle.…”