1.
Manjer, Jonas, et al.
(författare)
Breast cancer incidence in ex-smokers in relation to body mass index, weight gain and blood lipid levels
2001
Ingår i: European Journal of Cancer Prevention. - 1473-5709. ; 10:3, s. 281-287
Tidskriftsartikel (refereegranskat) abstract
According to several studies breast cancer is more common among former smokers. This study explores whether this association has any relationship with anthropometric measurements or blood lipid levels. The 2082 ex-smokers (mean age 49.9 years) in the Malmo Preventive Cohort were followed for an average of 13.3 years using official cancer registries. This yielded 93 incident breast cancer cases. Oestrogen receptor (ER) status was assessed by an immunological method. Incidence of breast cancer covaried with height, body mass index, weight gain and cholesterol levels. None of these associations reached statistical significance. Incidence of breast cancer increased over quartiles of serum triglycerides, Ptrend: 0.02, relative risk (RR) for triglycerides as a continuous variable: 1.46 (1.21-1.77). Nineteen tumours were ER negative; this subgroup was similarly related to high triglycerides, 1.76 (1.40-2.21). All results were similar when BMI and cholesterol levels were entered into the model. It is concluded that breast cancer incidence covaries with triglyceride levels in ex-smokers.
2.
Manjer, Jonas, et al.
(författare)
Increased incidence of small and well-differentiated breast tumours in post-menopausal women following hormone-replacement therapy
2001
Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 92:6, s. 919-922
Tidskriftsartikel (refereegranskat) abstract
Exposure to hormone-replacement therapy (HRT) has consistently been associated with an increased incidence of breast cancer, particularly of small tumours. Other tumour characteristics in relation to HRT have received less scientific attention. Our aim in this population-based prospective cohort study was to assess whether HRT is associated with an increased incidence of breast-cancer subgroups defined in terms of stage, type (according to the WHO system), Nottingham grade and the Nottingham Prognostic Index (NPI). Evaluation was based on a cohort of 5,865 post-menopausal women followed for an average of 9.8 years. Twenty percent of women reported current use of HRT at the time of the baseline interview. Record linkage with the Swedish Cancer Registry and local clinical registries identified 141 incident invasive breast-cancer cases. All tumours were reclassified by 1 pathologist. The incidence of breast cancer in HRT users was 377/10(5) and in non-users 221/10(5) person-years [relative risk (RR) = 1.72, 95% confidence interval (CI) 1.17-2.52]. This risk remained statistically significant after adjustment for established risk factors in a Cox proportional hazards analysis (RR = 1.66, 95% CI 1.12-2.45). Among HRT users, there was over-representation of cases with stage I tumours (adjusted RR = 2.33, 95% CI 1.44-3.76), of lobular carcinomas (RR = 4.38, 95% CI 1.60-12.0) and of tubular tumours (RR = 4.81, 95% CI 1.37-16.8). Nottingham grade I/II carcinomas (RR = 2.02, 95% CI 1.29-3.16) and cases with NPI < or = 3.4 (RR = 2.29, 95% CI 1.41-3.72) were similarly over-represented among HRT users. Incidence of breast cancer was increased in post-menopausal women who used HRT at baseline. Among HRT users, there was over-representation of tumours that, with regard to stage, type and grade, are associated with a favourable prognosis.
3.
Manjer, Jonas, et al.
(författare)
Risk of breast cancer in relation to anthropometry, blood pressure, blood lipids and glucose metabolism: a prospective study within the Malmo Preventive Project
2001
Ingår i: European Journal of Cancer Prevention. - 1473-5709. ; 10:1, s. 33-42
Tidskriftsartikel (refereegranskat) abstract
Insulin resistance may be a risk factor for breast cancer, possibly through increased levels of oestrogens or insulin-like growth factor I. Insulin resistance has been associated with obesity, hypertension, dyslipidaemia and impaired glucose tolerance. We studied the relation of these factors to breast cancer risk in a prospective cohort study of 9738 women. Menopausal status was defined a priori, and 112 cases of invasive breast carcinoma occurred in women who were premenopausal at baseline and 157 cases in subjects who were peri/postmenopausal. Relative risks (RR) for breast cancer were calculated by Cox's proportional hazards analysis for different quartiles of height, weight, body mass index, blood pressure, pulse rate and serum levels of total cholesterol, triglycerides, fasting blood glucose and glucose at 120 min after an oral dose of glucose. Peri/postmenopausal women had a significantly increased age-adjusted relative risk of breast cancer associated with height (RR = 1.78 for the highest versus lowest quartile), and the RR was increased over quartiles of cholesterol levels (P-value for trend: 0.05). No other significant associations were found. Adjustments for potential confounding factors or restriction of the analysis to cases and person-years before 55 years of age (premenopausal women), or after 55 years (peri/postmenopausal women), did not change
4.
Manjer, Jonas, et al.
(författare)
Smoking associated with hormone receptor negative breast cancer
2001
Ingår i: International Journal of Cancer. - 0020-7136. ; 91:4, s. 580-584
Tidskriftsartikel (refereegranskat) abstract
Women who smoke have less favourable prognosis following breast-cancer diagnosis. Some studies suggest that this is due to a more advanced stage at diagnosis, on average. Our present aim was to assess whether smoking is associated with other prognostic markers as well, e.g., hormone receptor status, histopathology and tumour differentiation. The evaluation was based on 268 incident cases in a cohort of 10,902 women (35% smokers) followed for an average of 12.4 years. An immunohistochemical method on recuts of tumour tissue was used to assess hormone receptor status. One pathologist classified all tumours according to the WHO system, Nottingham grade and Nottingham Prognostic Index. The relative risk (RR) of oestrogen receptor-negative tumours was, for current smokers, 2.21 [95% confidence interval (CI) 1.23-3.96] and, for ex-smokers, 2.67 (95% CI 1.41-5.06) compared to never-smokers. Ex-smokers had an increased risk of progesterone receptor-negative tumours (RR = 1.61, 95% CI 1.07-2.41), but there were no other significant associations between smoking habits and oestrogen receptor-positive or progesterone receptor-positive or -negative tumours. The incidence of Nottingham grade III tumours was higher in ex-smokers than in never-smokers (RR = 2.03, 95% CI 1.17-3.54). In terms of histopathological type or Nottingham Prognostic Index, there were no significant differences between smoking groups. We conclude that smoking is associated with an increased occurrence of hormone receptor-negative tumours.
5.
Manjer, Jonas, et al.
(författare)
The Malmö Diet and Cancer Study: representativity, cancer incidence and mortality in participants and non-participants
2001
Ingår i: European Journal of Cancer Prevention. - 1473-5709. ; 10:6, s. 489-499
Tidskriftsartikel (refereegranskat) abstract
In order to investigate potential selection bias in population-based cohort studies, participants (n = 28098) and non-participants (n = 40807) in the Malmo Diet and Cancer Study (MDCS) were compared with regard to cancer incidence and mortality. MDCS participants were also compared with participants in a mailed health survey with regard to subjective health, socio-demographic characteristics and lifestyle. Cancer incidence prior to recruitment was lower in non-participants, Cox proportional hazards analysis yielded a relative risk (RR) with a 95% confidence interval of 0.95 (0.90-1.00), compared with participants. During recruitment, cancer incidence was higher in non-participants, RR: 1.08 (1.01-1.17). Mortality was higher in non-participants both during, 3.55 (3.13-4.03), and following the recruitment period, 2.21 (2.03-2.41). The proportion reporting good health was higher in the MDCS than in the mailed health survey (where 74.6% participated), but the socio-demographic structure was similar. We conclude that mortality is higher in non-participants than in participants during recruitment and follow-up. It is also suggested that non-participants may have a lower cancer incidence prior to recruitment but a higher incidence during the recruitment period.
