Risk factors for adenocarcinoma of the cervix: a case-control study

Abstract

Summary To assess risk factors for cervical adenocarcinoma data were collected in a case-control study of 39 cases and 409 controls conducted in the greater Milan area. Questions were asked about personal characteristics and habits, gynaecologic and obstetric data, history of lifetime use of oral contraceptives and other female hormones, and general indicators of sexual habits (age at first intercourse and total number of sexual partners). The relative risk of cervical adenocarcinoma increased with number of births and abortions, early age at first birth and early age at first intercourse. These estimates did not materially change after adjustment for the potential reciprocal confounding effect. Further, there was a positive association with overweight, but an apparent association with lower education was not signilicant. No relationship emerged with oral contraceptive use. Thus, despite the similarities with the epidemiology of squamous cell cancer, reproductive patterns and other factors related to the risk of endometrial cancer (i.e., overweight) seem to play an important role in the risk of adenocarcinoma of cervix uteri.Adenocarcinoma of the cervix represents only about 5-10% of cervical neoplasms (Eide, 1987;Hurt et al., 1977;Menczer et al., 1978), but in selected areas its frequency has been suggested to rise significantly over the last ten years. Data from the USA have shown a two-fold increase in women aged under 35 years in absolute and proportional terms (Peters et al., 1986;Schwartz & Weiss, 1986). Likewise, an analysis of the Norway Cancer Register data from 1970to 1984(Eide, 1987 showed substantial decreases in squamous cell and undifferentiated neoplasms, but a 38% increase in the incidence of adenocarcinoma. This rise has been related, in terms of aetiological hypothesis, to oral contraceptive use in young women' (Peters et al., 1986). Further, the age distribution has been suggested to differ in various histotypes of cervical carcinoma, adenocarcinoma appearing later in life than squamous cell cancer of the cervix uteri (Menczer et al., 1978;Silcocks et al., 1987).From these descriptive epidemiological observations, it has been suggested that adenocarcinoma may differ in pathogenetic mechanisms and that its aetiology should be investigated with reference to hormonal, rather than infectious, aspects.Nonetheless, only scanty evidence has been published, to our knowledge, on risk factors for cervical adenocarcinoma from analytical epidemiological studies (Brinton et al., 1987;Silcocks et al., 1987). To assess the epidemiological features of invasive adenocarcinoma of the cervix, we have therefore analysed data from a hospital-based case-control study of cervical neoplasms conducted in the greater Milan area, Northern Italy. Materials and methodsSince 1981, we have been conducting a case-control study of cervical neoplasia. The design of this investigation has already been described (La Vecchia et al., 1986 CasesThe cases studied were women admitted to the Obstetrics and Gynaecology Clinics of the ...

Risk factors for adenocarcinoma and squamous cell carcinoma of the cervix in women aged 20–44 years: the UK National Case–Control Study of Cervical Cancer

“…Sexual behaviour, and in particular the number of sexual partners, is strongly associated both with HPV infection and with the risk of squamous cell carcinoma of the cervix. Most controlled studies have also found the risk of cervical adenocarcinoma to increase directly with the lifetime number of sexual partners (Brinton et al, 1987;Parazzini et al, 1988;Ursin et al, 1996;Chichareon et al, 1998;Madeleine et al, 2001;Altekruse et al, 2003), and studies providing a direct comparison have found no differences in risk between adenocarcinoma and squamous cell carcinoma in all and in HPV-positive women (Brinton et al, 1987;Horowitz et al, 1988;Brinton et al, 1993;Chichareon et al, 1998;Ngelangel et al, 1998). Our results are consistent with existing evidence.…”

“…Munoz et al (2002), in a pooled analysis of 10 case -control studies in HPV-positive women, found that the risk of squamous cell carcinoma increased with the number of fullterm pregnancies; there was no equivalent trend in the risk of adenocarcinoma and adenosquamous carcinoma, although the risk of adenocarcinoma was higher in parous women than in nulliparous. Most other case -control studies, including those taking HPV infection into account, have shown an association with parity for squamous cell carcinoma of the cervix (Brinton et al, 1987Parazzini et al, 1988;Hildesheim et al, 2001;Altekruse et al, 2003) but, with the exception of one study (Parazzini et al, 1988), not for adenocarcinoma (Brinton et al, 1987Ursin et al, 1996). Altekruse et al (2003) found an inverse relationship between parity and cervical adenocarcinoma risk.…”

“…This is consistent with the results of previous studies (Plummer et al, in press). No study has reported a significant association between smoking and the risk of adenocarcinoma of the cervix (Brinton et al, 1987;Parazzini et al, 1988;Ursin et al, 1996;Chichareon et al, 1998;Ngelangel et al, 1998;Lacey et al, 2001;Madeleine et al, 2001) and of four case -control studies directly comparing risk for adenocarcinoma and squamous cell carcinoma, smoking was found to be a significant risk factor for squamous cell carcinoma but not for adenocarcinoma in two (Brinton et al, 1987, Ngelangel et al, 1998, with no statistically significant association between smoking and cervical cancer in the other two studies (Chichareon et al, 1998;Lacey et al, 2001). In the study by Lacey et al, the results suggested that smoking may increase the risk of squamous cell carcinoma, but decrease the risk of adenocarcinoma (with odds ratios for ever smoking of 1.6 (0.9 -2.9) for squamous cell carcinoma and 0.6 (0.3 -1.1) for adenocarcinoma).…”

“…Early reports from case -case studies suggesting that squamous cell and adenocarcinomas differed in relation to socioeconomic status may have been due to confounding by factors such as smoking. Four out of five case -control studies with information on body weight have reported an increased risk of adenocarcinoma of the cervix in women with high body mass index (Parazzini et al, 1988;Lacey et al, 2001), weight (Brinton et al, 1987;Lacey et al, 2001) or weight gain in adult life (Ursin 96), with no association for squamous cell carcinoma where a direct comparison was made (Brinton et al, 1987;Lacey et al, 2001). The remaining study found no evidence of an association between weight and risk of adenocarcinoma or squamous cell carcinoma , and no consistent difference was found in body weight between women with adenocarcinoma and those with squamous cell carcinoma in case -case studies (Korhonen, 1980;Milsom and Friberg, 1983;Honore et al, 1991;Hopkins and Morley, 1991).…”

Reproductive factors and risk of cervical cancer by cell type. A prospective study

“…Our data are in agreement with the findings of Brinton et al (1987b) who observed no association with parity, and lend support to previous results which have indicated differing aetiologies for squamous cell carcinomas and adenocarcinomas of the cervix uteri (Menczer et al, 1978;Silcocks et al, 1987). However, our results contrast with findings of Parazzini et al (1988). In a recent case-control study of 39 women with adenocarcinoma of the cervix they observed increased risk with increasing number of pregnancies and early age at first birth.…”