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ABSTRACT: To explore whether the anatomic distribution of melanoma differs with ambient sunlight levels, we compared age- and site-specific
melanoma incidence in two genetically similar populations from different geographic regions. We ascertained all new cases
of invasive cutaneous melanoma in the west of Scotland and Queensland 1982–2001. Melanoma incidence was calculated for four
anatomic regions (head and neck, trunk, upper and lower limbs), standardized to the European population and adjusted for relative
surface area of each site. Highest rates among males aged <40 years and 40–59 years were observed on the trunk, but on the
upper limbs among Queensland females and lower limbs among Scottish females. After age 60, melanoma rates were highest on
the head and neck in both sexes. In both sexes and at all ages, lower limb melanomas were more common in Scotland than expected
from the Queensland population. These analyses indicate that while the overall distribution of melanoma is similar in populations
with different levels of ambient sunlight, important differences remain. Identifying the causes of these differences is likely
to provide better understanding of how sunlight causes melanoma.
Cancer Causes and Control 04/2012; 18(5):485-491. · 2.88 Impact Factor
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ABSTRACT: To investigate risk factors for lentigo maligna melanoma (LMM) compared with superficial spreading melanoma (SSM).
Population-based case-control study in Queensland, Australia.
General community.
Population-based sample of 49 patients with LMM and 141 with SSM (in situ or invasive) aged 14 to 86 years at diagnosis in 1979 and 1980 and 232 control subjects. Response rates were 97.1% in cases and 91.8% in controls.
Risks of both subtypes in relation to phenotypic and environmental factors, estimated by multinomial logistic regression.
The number of solar lentigines was the strongest determinant for LMM (odds ratio [OR], 15.93; P < .001 for trend) and significantly weaker for SSM (4.61; P < .001 for trend; P = .04 for homogeneity). Skin cancer history was significantly associated with LMM (OR, 2.84) but not with SSM (1.33; P = .07 for homogeneity). In contrast, the number of nevi was the strongest determinant for SSM (OR, 23.22; P < .001 for trend) while significantly weaker for LMM (3.60; P = .02 for trend; P < .001 for homogeneity). Multiple lifetime sunburns almost tripled the risk for SSM, whereas no association was detected with LMM (P = .04 for homogeneity). Shared risk factors for both subtypes were the number of solar keratoses (P < .001 for trend for both) and sun-sensitive complexion (ie, light eye/hair colors, sunburn propensity, and freckling) (2-fold to 5-fold increased risks).
A propensity to lentigines is a stronger predictor of LMM, whereas high nevus propensity is a stronger predictor of SSM. Skin cancer history appears to determine LMM risk only, whereas the number of lifetime sunburns determines SSM only. Prevention strategies could be tailored differently given these distinctive points of difference.
Archives of dermatology 02/2012; 148(2):164-70. · 4.76 Impact Factor
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ABSTRACT: The objective of this study was to investigate the risk factors for melanoma on the arms and legs in comparison with well-known risk factors for trunk melanoma. The study was a population-based case-control study of 77 individuals with limb (25 arm; 52 leg) and 86 with trunk melanoma, who were representative of all the individuals newly-diagnosed with primary limb melanomas in Queensland during 1979-1980 and 232 controls. A single physician interviewed and examined all individuals and assessed complexion type, sun exposure history and other potential risk factors and clinical features. After multivariate analysis, the strongest risk factor for both limb and trunk melanomas was the presence of more than 10 naevi on the arm (odds ratio limb melanoma=41.4, 95% confidence interval 10.4-164), though on histology, a preexisting naevus was more strongly associated with trunk than limb melanoma (P<0.004). Associations with blonde/light brown hair, propensity to freckle and sunburn were similar for melanoma on both sites. A lifetime history of painful sunburns significantly raised the risk of trunk but not limb melanoma, whereas solar keratoses on the arm or face were more strongly associated with limb than with trunk melanoma (marginally significant, P(homogeneity)=0.056). High ambient solar ultraviolet radiation in adolescence was also a stronger risk factor for limb than for trunk melanoma. In conclusion, this population-based investigation into specific differences in causes of limb versus melanomas of other sites suggests that the risk factor profile is intermediate between the profiles for head/neck melanoma (mostly cumulative sun damage) and for trunk melanomas (most strongly related to naevi).
Melanoma research 11/2011; 22(1):86-91. · 2.06 Impact Factor
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Nicola C Douglas,
Theo Borgovan,
Melissa J Carroll,
Patricia F Williams,
Elizabeth G Berry, Victor Siskind,
Andreas F Hoedl,
Elisabeth M T Wurm,
B Mark Smithers,
Adele C Green,
H Peter Soyer
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ABSTRACT: Dermoscopic understanding of naevus characteristics is essential baseline knowledge for identifying early malignant changes.
This cross-sectional study includes 34 patients (56% female, mean age 48 years) at high risk of melanoma (personal or a first degree family member with history of melanoma) and 31 moderate/low melanoma risk volunteers (55% female, mean age 37 years) recruited at the Princess Alexandra Hospital, Brisbane, between October 2009 and March 2010. Participants received full body and individual dermoscopic imaging of clinically significant naevi (≥2 mm on the back of male/female and lower limbs of female and ≥5 mm at other body sites). Dermoscopic patterns of naevi were compared between people at high versus moderate/low melanoma risk according to age and body site.
In both high and moderate/low risk groups, globular naevi predominated on the head/neck and abdomen/chest, reticular and non-specific naevi on the back, and non-specific pattern on the upper and lower limbs. Non-specific naevi were the most common in all age groups. In both risk groups, globular naevi were more frequent in the younger age bracket, and reticular naevi were more frequent in the older age bracket. Mixed naevus patterns were infrequent and were more common in the younger age brackets of both risk groups.
Our preliminary data shows that dermoscopic naevus patterns were similar for age and body site in people at different levels of melanoma risk, suggesting high melanoma risk does not influence dermoscopic naevus patterns.
Australasian Journal of Dermatology 11/2011; 52(4):248-53. · 1.00 Impact Factor
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ABSTRACT: Although risk factors for primary cutaneous melanoma are well defined, relatively little is known about predictors for second primary melanoma. Given the rising incidence of this cancer, coupled with improvements in survival, there is a prevalent and growing pool of patients at risk of second primary melanomas. To identify the predictors of second primary melanoma, we followed a cohort of 1,083 Queensland patients diagnosed with incident melanoma between 1982 and 1990 and who completed a baseline questionnaire. During a median follow-up of 16.5 years, 221 patients were diagnosed with at least one additional primary melanoma. In multivariate analyses, second primary melanomas were associated with high nevus count (hazard ratio (HR), 2.91; 95% confidence interval (CI) 1.94-4.35), high familial melanoma risk (HR, 2.12; 95% CI 1.34-3.36), fair skin (HR, 1.51; 95% CI 1.06-2.16), inability to tan (HR, 1.66; 95% CI 1.13-2.43), an in situ first primary melanoma (HR, 1.36; 95% CI 0.99-1.87), and male sex (HR, 1.49; 95% CI 1.12-2.00). Patients whose first primary was lentigo maligna melanoma (HR, 1.80; 95% CI 1.05-3.07) or nodular melanoma (HR, 2.13; 95% CI 1.21-3.74) had higher risks of subsequent primaries than patients whose first primary tumor was superficial spreading melanoma. These characteristics could be assessed in patients presenting with first primary melanoma to evaluate risk of developing a second primary.
Journal of Investigative Dermatology 10/2010; 131(2):461-7. · 6.31 Impact Factor
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ABSTRACT: Several studies have found inverse associations between breastfeeding and ovarian cancer occurrence but there are inconsistencies. The relationship with breastfeeding duration is unclear, and it is uncertain whether the association varies according to histological subtype of ovarian cancer. We sought to clarify these issues.
Parous women who participated in an Australia-wide population-based case-control study of epithelial ovarian cancer between 2001 and 2005 (1,092 cases and 1,288 controls) completed a reproductive/lifestyle questionnaire. Logistic regression was used to calculate odds ratios and 95% confidence intervals to investigate relations between breastfeeding and ovarian cancer.
We found a strong inverse association between total duration of breastfeeding (all episodes combined) and ovarian cancer occurrence (OR = 0.986, 95% CI 0.978-0.994 per month of breastfeeding) that appeared to be independent of parity. However, individual episodes of lactation beyond 12 months conferred no appreciable additional benefit. The relation with breastfeeding appeared to vary by histological subtype such that we saw no association between duration of breastfeeding and borderline serous cancers or mucinous cancers, but inverse associations for the other subtypes, although these were not always statistically significant.
A long total duration of breastfeeding appears to be associated with a substantial reduction in the overall risk of ovarian cancer, independent of the decrease in risk due to childbirth, but this may vary according to histological subtype.
Cancer Causes and Control 09/2009; 21(1):109-16. · 2.88 Impact Factor
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Yu-mei Chang,
Jennifer H Barrett,
D Timothy Bishop,
Bruce K Armstrong,
Veronique Bataille,
Wilma Bergman,
Marianne Berwick,
Paige M Bracci,
J Mark Elwood,
Marc S Ernstoff, [......],
Rona M Mackie,
Håkan Olsson,
Anne Østerlind,
Timothy R Rebbeck,
Peter Sasieni, Victor Siskind,
Anthony J Swerdlow,
Linda Titus-Ernstoff,
Michael S Zens,
Julia A Newton-Bishop
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ABSTRACT: Melanoma risk is related to sun exposure; we have investigated risk variation by tumour site and latitude.
We performed a pooled analysis of 15 case-control studies (5700 melanoma cases and 7216 controls), correlating patterns of sun exposure, sunburn and solar keratoses (three studies) with melanoma risk. Pooled odds ratios (pORs) and 95% Bayesian confidence intervals (CIs) were estimated using Bayesian unconditional polytomous logistic random-coefficients models.
Recreational sun exposure was a risk factor for melanoma on the trunk (pOR = 1.7; 95% CI: 1.4-2.2) and limbs (pOR = 1.4; 95% CI: 1.1-1.7), but not head and neck (pOR = 1.1; 95% CI: 0.8-1.4), across latitudes. Occupational sun exposure was associated with risk of melanoma on the head and neck at low latitudes (pOR = 1.7; 95% CI: 1.0-3.0). Total sun exposure was associated with increased risk of melanoma on the limbs at low latitudes (pOR = 1.5; 95% CI: 1.0-2.2), but not at other body sites or other latitudes. The pORs for sunburn in childhood were 1.5 (95% CI: 1.3-1.7), 1.5 (95% CI: 1.3-1.7) and 1.4 (95% CI: 1.1-1.7) for melanoma on the trunk, limbs, and head and neck, respectively, showing little variation across latitudes. The presence of head and neck solar keratoses was associated with increased risk of melanoma on the head and neck (pOR = 4.0; 95% CI: 1.7-9.1) and limbs (pOR = 4.0; 95% CI: 1.9-8.4).
Melanoma risk at different body sites is associated with different amounts and patterns of sun exposure. Recreational sun exposure and sunburn are strong predictors of melanoma at all latitudes, whereas measures of occupational and total sun exposure appear to predict melanoma predominately at low latitudes.
International Journal of Epidemiology 05/2009; 38(3):814-30. · 6.41 Impact Factor
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Yu-mei Chang,
Julia A Newton-Bishop,
D Timothy Bishop,
Bruce K Armstrong,
Veronique Bataille,
Wilma Bergman,
Marianne Berwick,
Paige M Bracci,
J Mark Elwood,
Marc S Ernstoff, [......],
Anne Østerlind,
Timothy R Rebbeck,
Kristian Reich,
Peter Sasieni, Victor Siskind,
Anthony J Swerdlow,
Linda Titus-Ernstoff,
Michael S Zens,
Andreas Ziegler,
Jennifer H Barrett
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ABSTRACT: An abnormal nevus phenotype is associated with an increased risk of melanoma. We report a pooled analysis conducted using individual nevus data from 15 case-control studies (5,421 melanoma cases and 6,966 controls). The aims were to quantify the risk better and to determine whether relative risk is varied by latitude. Bayesian unconditional logistic random coefficients models were employed to study the risk associated with nevus characteristics. Participants with whole body nevus counts in the highest of 4 population-based categories had a greatly increased risk of melanoma compared with those in the lowest category (pooled odds ratio (pOR) 6.9 (95% confidence interval (CI): 4.4, 11.2) for those aged<50 years and pOR 5.1 (95% CI: 3.6, 7.5) for those aged>or=50). The pOR for presence compared with absence of any clinically atypical nevi was 4.0 (95% CI: 2.8, 5.8). The pORs for 1-2 and >or=3 large nevi on the body compared with none were 2.9 (95% CI: 1.9, 4.3) and 7.1 (95% CI: 4.7, 11.6), respectively. The relative heterogeneities among studies were small for most measures of nevus phenotype, except for the analysis of nevus counts on the arms, which may have been due to methodological differences among studies. The pooled analysis also suggested that an abnormal nevus phenotype is associated most with melanomas on intermittently sun-exposed sites. The presence of increased numbers of nevi, large nevi and clinically atypical nevi on the body are robust risk factors for melanoma showing little variation in relative risk among studies performed at different latitudes.
International Journal of Cancer 10/2008; 124(2):420-8. · 5.44 Impact Factor
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ABSTRACT: We compared trends in melanoma incidence by body site in two populations exposed to different levels of sunlight and different approaches to melanoma prevention. We analysed site-specific melanoma incidence during the period 1982-2001 in Queensland, Australia (n=28 862 invasive melanomas; 2536 lentigo maligna melanomas) and the west of Scotland (n=4278 invasive melanomas; 525 lentigo maligna melanomas). Analyses were stratified by sex and age group (<40 years, 40-59 years, >/=60 years). We estimated annual percentage change (APC) in melanoma incidence by regressing the logarithms of the rates and exponentiating the coefficients. Among men, overall melanoma incidence increased log-linearly in both settings, but significantly more rapidly in the west of Scotland (APC 2.8%) than Queensland (APC 1.4%). Rates of increase among Scottish men were higher for every body site and all ages than among Queensland men. Among women, overall melanoma incidence increased more rapidly among Scottish (APC 1.8%) than Queensland women (APC 0.7%). Most discrepant were trends in upper limb melanomas, which underwent large annual increases among Scottish women, but declined among younger Queensland women. Melanoma incidence continues to rise rapidly in all age groups in Scotland and among older people in Queensland. Rates of melanoma in younger people in Queensland are stabilizing, as might be expected if primary prevention campaigns were effective in reducing solar exposure. Variations in rates of change at different body sites warrant further monitoring.
European journal of cancer prevention: the official journal of the European Cancer Prevention Organisation (ECP) 07/2008; 17(3):243-50. · 2.21 Impact Factor
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ABSTRACT: Both hysterectomy and tubal sterilisation offer significant protection from ovarian cancer, and the risk of cardiovascular disease in women is lowered after hysterectomy. Since little is known about the accuracy of women's self–reports of these procedures, we assessed their reliability and validity using data obtained in a case–control study of ovarian cancer. There was 100 per cent repeatability for both positive and negative histories of hysterectomy and tubal sterilisation among a small sample of women on reinterview. Verification of surgery was sought against surgeons' or medical records, or if these were unavailable, from randomly selected current general practitioners for 51 cases and 155 controls reporting a hysterectomy and 73 cases and 137 controls reporting a tubal sterilisation. Validation rate for self–reported hysterectomy against medical reports (32 cases, 96 controls) was 96 per cent (95 per cent confidence interval (CI) 91 to 99) and for tubal sterilisation (32 cases, 77 controls) it was 88 per cent (CI 81 to 93), which is likely to be an underestimate. Although findings are based on small numbers of women for whom medical reports could be ascertained, they are consistent with other findings that suggest women have good recall of past histories of hysterectomy and tubal sterilisation; this allows long–term effects of these procedures to be studied with reasonable accuracy from self–reports.
Australian and New Zealand Journal of Public Health 05/2008; 21(3):337 - 340. · 1.20 Impact Factor
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Amanda J Baxter,
Maria Celia Hughes,
Marina Kvaskoff, Victor Siskind,
Sri Shekar,
Joanne F Aitken,
Adele C Green,
David L Duffy,
Nicholas K Hayward,
Nicholas G Martin,
David C Whiteman
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ABSTRACT: Cutaneous malignant melanoma (CMM) is a major health issue in Queensland, Australia, which has the world's highest incidence. Recent molecular and epidemiologic studies suggest that CMM arises through multiple etiological pathways involving gene-environment interactions. Understanding the potential mechanisms leading to CMM requires larger studies than those previously conducted. This article describes the design and baseline characteristics of Q-MEGA, the Queensland Study of Melanoma: Environmental and Genetic Associations, which followed up 4 population-based samples of CMM patients in Queensland, including children, adolescents, men aged over 50, and a large sample of adult cases and their families, including twins. Q-MEGA aims to investigate the roles of genetic and environmental factors, and their interaction, in the etiology of melanoma. Three thousand, four hundred and seventy-one participants took part in the follow-up study and were administered a computer-assisted telephone interview in 2002-2005. Updated data on environmental and phenotypic risk factors, and 2777 blood samples were collected from interviewed participants as well as a subset of relatives. This study provides a large and well-described population-based sample of CMM cases with follow-up data. Characteristics of the cases and repeatability of sun exposure and phenotype measures between the baseline and the follow-up surveys, from 6 to 17 years later, are also described.
Twin Research and Human Genetics 05/2008; 11(2):183-96. · 1.70 Impact Factor
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ABSTRACT: To explore whether the anatomic distribution of melanoma differs with ambient sunlight levels, we compared age- and site-specific melanoma incidence in two genetically similar populations from different geographic regions. We ascertained all new cases of invasive cutaneous melanoma in the west of Scotland and Queensland 1982-2001. Melanoma incidence was calculated for four anatomic regions (head and neck, trunk, upper and lower limbs), standardized to the European population and adjusted for relative surface area of each site. Highest rates among males aged <40 years and 40-59 years were observed on the trunk, but on the upper limbs among Queensland females and lower limbs among Scottish females. After age 60, melanoma rates were highest on the head and neck in both sexes. In both sexes and at all ages, lower limb melanomas were more common in Scotland than expected from the Queensland population. These analyses indicate that while the overall distribution of melanoma is similar in populations with different levels of ambient sunlight, important differences remain. Identifying the causes of these differences is likely to provide better understanding of how sunlight causes melanoma.
Cancer Causes and Control 06/2007; 18(5):485-91. · 2.88 Impact Factor
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ABSTRACT: The anatomic distribution of cutaneous melanoma reflects people's levels and patterns of sun exposure. While examining trends of incident invasive melanomas by site in recent decades in Australia we noted significant increases in incidence on the ears but not the face or any other site in women younger than 40 years, by 6% (95% confidence interval [CI] 2-10%) per year, and 40-59 years by 7% (95% CI 4-10%) per year. Men of the same age showed no corresponding changes in ear melanoma. However incidence rates of ear melanoma in general were fourfold higher in males than females in Australia. Further, using data from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program, rates of invasive melanoma on the ear were found to be sevenfold higher in males than females in the US population in the same period. Higher rates of scalp and neck melanomas were also seen in men and women in both populations. We therefore speculated that the isolated rises of ear melanoma in younger women in Australia, and the higher overall rates of ear, scalp and neck melanoma in men compared with women, reflect differences in hair coverage. We tested the specific hypothesis that hair cover reduces sun exposure of the ears using experimental manikins and found that hair cover of the ear reduced solar ultraviolet-B exposure by 81% [SE +/-8] compared with uncovered ears. We conclude that hair cover can protect against invasive melanoma on the ear and may similarly protect on the scalp and neck. When discretionary, hair may be an important additional factor to be considered for melanoma prevention.
Cancer Causes and Control 01/2007; 17(10):1263-6. · 2.88 Impact Factor
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ABSTRACT: Of the few factors known to be associated with epithelial ovarian cancer, the most consistently observed relate to women's reproductive function, although even here uncertainties remain. We have undertaken a case-control study involving personal interviews with over 1,600 women, the largest of its kind to date, to investigate further the associations between women's reproductive histories and other factors and the development of ovarian cancer. Cases were drawn from women diagnosed with epithelial ovarian cancer in 3 Australian states, Queensland, New South Wales and Victoria, between August 1990 and December 1993, and controls were drawn at random from the electoral roll, stratified by age and geographic region. Trained interviewers administered standard questionnaires to obtain detailed information about women's reproductive and contraceptive histories and other factors of interest, such as smoking and family history of ovarian or other cancer. Findings were based on data from 824 cases and 860 controls and confirmed the reduced risk of ovarian cancer associated with increasing parity and duration of use of the oral contraceptive pill (OCP), hysterectomy and tubal ligation. The strongest association of all was seen with use of the OCP for 10 years or more. An inverse association between ovarian cancer and age at first birth was observed, but this was not statistically significant. There were no associations between development of ovarian cancer and number of incomplete pregnancies, use of hormone replacement therapy or menstrual history. Among other factors considered, education after leaving school was negatively associated and high body mass index, family history of ovarian cancer, use of talc in the abdominal or perineal region and smoking were positively associated with occurrence of ovarian cancer. © 1995 Wiley-Liss, Inc.
International Journal of Cancer 07/2006; 62(6):678 - 684. · 5.44 Impact Factor
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ABSTRACT: Emerging evidence suggests that melanomas arising on the head and neck that are not lentigo maligna melanomas have different associations with phenotypic and environmental risk factors than those on the trunk and other sites. We sought to test this hypothesis in a population-based study in Queensland, Australia.
Risk factor data were collected from 2360 participants with incident cutaneous melanoma diagnosed 1982--1990, including 167 participants with lentigo maligna melanoma. For each risk factor, polytomous logistic regression analysis, using the trunk as a reference category, was used to estimate the odds ratio and 95% confidence interval for cutaneous melanomas by anatomical site.
Participants with melanomas of the head and neck were significantly older than those with melanomas of the trunk (males 52.7 versus 49.7 years; females 47.8 versus 40.5 years). Compared with patients with truncal melanomas, those of the head and neck were less likely to have many nevi (OR 0.41, 95% CI 0.13--1.31), although this did not reach statistical significance. Among females, melanomas of the lower limb were negatively associated with a past history of non-melanoma skin cancer (OR 0.41, 95% CI 0.23-0.74).
We have observed heterogeneity for melanoma risk by anatomical site, lending weight to the hypothesis that cutaneous melanomas may develop through multiple causal pathways.
Cancer Causes and Control 05/2005; 16(3):193-9. · 2.88 Impact Factor
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ABSTRACT: Incessant ovulation is thought to be one of the primary causes of epithelial ovarian cancer. However, the effects of ovulation at different ages and of the various exposures or events that suppress ovulation have not been established. We used data from an Australian case-control study of 791 ovarian cancer cases and 853 controls to examine the effect of ovulation on ovarian cancer risk. The total number of lifetime ovulations was calculated using information provided in a monthly contraceptive/reproductive calendar, as well as incorporating other information such as average menstrual cycle length. An increase of 1 year's worth of ovulation was associated with a 6% increase in risk of ovarian cancer (95% confidence interval [CI] = 4-8%). Ovulations in the 20-29-year age group were associated with the greatest risk, with a 20% increase in risk associated with each year of ovulation during this age period (95% CI = 13-26%). When the effects of different exposures that suppress ovulation were compared, there was an indication that some factors may have a greater effect than others. These findings support the theory that incessant ovulation is a major contributor to the occurrence of ovarian cancer and suggest that ovulations during the 20s may be those most associated with disease risk.
International Journal of Cancer 04/2003; 104(2):228-32. · 5.44 Impact Factor
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Gynecologic Oncology 02/2003; 88(1 Pt 2):S145-8. · 3.89 Impact Factor
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ABSTRACT: Recent animal studies suggest that progestagen-induced apoptosis of transformed ovarian surface epithelial cells may underlie the observed protective effect of pregnancy on the risk of ovarian cancer. Assuming that increasing numbers of cells are transformed with advancing age, we postulated that the benefits of pregnancy would be greater for older than younger women and tested this hypothesis in a population-based case-control study. We conducted interviews with 620 parous women, ages 18-79 years, with histologically confirmed incident ovarian cancer and 723 parous controls of the same age. Detailed information was collected on reproductive history, as well as hormonal exposures, smoking, medical history, and other factors. We estimated the relative risk of ovarian cancer associated with births at different ages through multiple logistic regression models. After adjusting for parity, older age at first and last births, and shorter time since last birth were all associated with significantly reduced risks of ovarian cancer. Age at first birth and time since last birth were not associated with ovarian cancer when adjusted for each other, whereas age at last birth remained strongly protective [odds ratio (OR), 0.57; 95% confidence interval (CI), 0.36-0.90] among women >35 years versus women less than 25 years. The effect was independent of total parity (per year of age among women with one birth: OR, 0.93; 95%CI, 0.87-1.01; among women with four or more births: OR, 0.96; 95%CI, 0.90-1.02). Our finding that ovarian cancer risk is reduced by pregnancy at older ages is further evidence that pregnancy confers a benefit beyond anovulation and is consistent with the theory that ovarian surface epithelial cell apoptosis induced by pregnancy hormones may be the underlying protective mechanism.
Cancer Epidemiology Biomarkers & Prevention 01/2003; 12(1):42-6. · 4.12 Impact Factor
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Epidemiology 10/2002; 13(5):609-10. · 5.57 Impact Factor
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ABSTRACT: All melanocytic nevi on the faces and necks of a cohort of students, initially aged 12-14 y, were mapped and photographed annually for 4 y. The features of each nevus were charted yearly noting changes in size and profile, and the appearance or disappearance of any nevi on a student's face and neck was recorded. Nevi were classified by size (small, < 2 mm; medium, 2-5 mm; large, > 5 mm), and by profile (flat, raised). Data from 20 adolescents selected randomly from the cohort for detailed analysis showed males had about twice as many nevi as females, but there was little difference between sexes in their patterns of nevus development. Approximately half the nevi were small in all years; under 5% were large. Over the 4 y of follow-up the proportion of flat nevi dropped from 70% to 57%, whereas nevus numbers increased by 47% in year 1, with smaller increases in older students. Most new or disappearing nevi were small and flat, although both incident and disappearing nevi could be larger and/or raised. Of the existing nevi that altered in the follow-up period, the tendency was towards an increase in size among raised but not among flat nevi; a lowering of profile among small nevi; and a raising of profile among larger nevi; but there were many exceptions to this pattern. Among several host factors examined, inability to tan after sun exposure was found to be significantly negatively associated with the propensity of nevi to change size over the study period. Overall our findings indicate that, contrary to conventional belief, there is a measurable turnover among melanocytic nevi even in early life.
Journal of Investigative Dermatology 03/2002; 118(3):500-4. · 6.31 Impact Factor
