Nurses' Health Study Contributions on the Epidemiology of Less Common Cancers: Endometrial, Ovarian, Pancreatic, and Hematologic

Inflammatory and insulinemic dietary and lifestyle patterns and incidence of endometrial cancer: the multiethnic cohort

BACKGROUND

The incidence of endometrial cancer (EC) is increasing, particularly among racial and ethnic minority groups. Obesity is an established EC risk factor, and obesity-related inflammation and hyperinsulinemia may play an important role in EC etiology.

OBJECTIVES

We examined the association of 5 empirical hypothesis-oriented dietary and lifestyle indices, which assess the inflammatory and insulinemic potentials of diet and lifestyle, with risk of EC in ethnically diverse females.

METHODS

We included 60,441 female participants from the multiethnic cohort study, a cohort-based in the United States, who were African American, Japanese American, Latino, Native Hawaiian, or White, aged 45-75 y at baseline in 1993-1996. Using a quantitative food frequency questionnaire at baseline, we computed the empirical dietary inflammatory pattern (EDIP), empirical dietary index for hyperinsulinemia (EDIH), empirical lifestyle index for hyperinsulinemia (ELIH), empirical dietary index for insulin resistance (EDIR), and empirical lifestyle index for insulin resistance (ELIR). Multivariable Cox models adjusting for known risk factors for EC were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between each index (using quintiles) and EC risk.

RESULTS

We identified 1328 incident EC cases with a median follow-up of 25.2 y (IQR = 7.4 y). Females with higher ELIH had an increased risk of EC (HRQ5vsQ1 = 2.58, 95% CI: 2.16, 3.09; Ptrend < 0.01). Similarly, higher ELIR was significantly associated with an increased risk of EC (HRQ5vsQ1 = 2.89, 95% CI: 2.37, 3.53; Ptrend < 0.01). EDIP, EDIH, and EDIR were not associated with EC risk. Increased risk of EC with ELIH (all Ptrend < 0.01) and ELIR (all Ptrend < 0.01) was found in all racial and ethnic groups.

CONCLUSIONS

In this ethnically diverse cohort, lifestyle patterns with higher insulinemic potential were associated with an increased risk of EC. Lifestyle changes that include more physical activity and achieving a healthy body weight, in addition to reducing insulinemic and diets, may lower EC risk.

Hypertension and Risk of Endometrial Cancer: A Pooled Analysis in the Epidemiology of Endometrial Cancer Consortium (E2C2)

BACKGROUND

The incidence rates of endometrial cancer are increasing, which may partly be explained by the rising prevalence of obesity, an established risk factor for endometrial cancer. Hypertension, another component of metabolic syndrome, is also increasing in prevalence, and emerging evidence suggests that it may be associated with the development of certain cancers. The role of hypertension independent of other components of metabolic syndrome in the etiology of endometrial cancer remains unclear. In this study, we evaluated hypertension as an independent risk factor for endometrial cancer and whether this association is modified by other established risk factors.

METHODS

We included 15,631 endometrial cancer cases and 42,239 controls matched on age, race, and study-specific factors from 29 studies in the Epidemiology of Endometrial Cancer Consortium. We used multivariable unconditional logistic regression models to estimate ORs and 95% confidence intervals (CI) to evaluate the association between hypertension and endometrial cancer and whether this association differed by study design, race/ethnicity, body mass index, diabetes status, smoking status, or reproductive factors.

RESULTS

Hypertension was associated with an increased risk of endometrial cancer (OR, 1.14; 95% CI, 1.09-1.19). There was significant heterogeneity by study design (Phet < 0.01), with a stronger magnitude of association observed among case-control versus cohort studies. Stronger associations were also noted for pre-/perimenopausal women and never users of postmenopausal hormone therapy.

CONCLUSIONS

Hypertension is associated with endometrial cancer risk independently from known risk factors. Future research should focus on biologic mechanisms underlying this association.

IMPACT

This study provides evidence that hypertension may be an independent risk factor for endometrial cancer.

Differential trends in rising endometrial cancer incidence by age, race, and ethnicity

Endometrial cancer (EC) incidence is on the rise. Although early-onset endometrial cancer (EOEC; age at diagnosis <50 years) is relatively uncommon, the incidence of EOEC has been reportedly increasing in recent decades. However, the rising EOEC has not been thoroughly described with regard to the racial and ethnic disparities and compared with late-onset EC (age at diagnosis ≥50 years). We used the Cancer in North America (CiNA) Analytic File, 1995-2018, from the North American Association of Central Cancer Registries, which allowed us to examine trends in invasive EC incidence by racial and ethnic groups and by age at diagnosis. We found striking differences for demographic and tumor characteristics as well as racial and ethnic patterns and time trends in EC incidence between EOEC and late-onset EC. The faster increases in EOEC incidence rates, especially among non-White women, mirror similar observations in other cancers, pointing to a possible link with rising obesity epidemic in younger generations.

A Systematic Review and Meta-analysis on the Role of Statins in the Prevention of Mortality Following Pancreatic Cancer

BACKGROUND

Pancreatic cancer (PC) is a type of cancer with a high incidence and case-fatality rate.

OBJECTIVE

This study aimed to evaluate the role of statins in preventing mortality following PC based on scientific evidence with systematic review and meta-analysis method.

METHODS

This meta-analysis considered studies published from 1980 till the end of 2022 in ISI Web of Science, Scopus, PubMed, Cochrane, Science Direct, Google Scholar, and Embase databases. Funnel diagrams and Begg's and Egger's tests were used to assess the publication bias.

RESULTS

In general, this meta-analysis has included 19 studies (13 cohort studies, 4 case-control, and 2 randomized clinical trials (RCTs)) and a total of 100,888 patients with PC. The risk of mortality of PC in statin users in total was 0.86 (95% CI: 0.80 - 0.92, P-value <0.001); in the case-control studies, it was equal to 0.53 (0.34-0.83); in the cohort studies, it was equal to 0.87 (0.82-0.92, P-value <0.001); in RCTs, it was equal to 1.19 (0.99-1.42, P-value <0.001); in studies with good quality score category, it was equal to 0.92 (0.86-0.99, P-value <0.001), and in articles of the moderate quality score category, it was equal to 0.73 (0.64-0.84, P-value <0.001). The results of statistical tests indicated the existence of publication bias (Begg's test (P-value = 0.002) and Egger's test (P-value = 0.004)).

CONCLUSION

Statins reduce the risk of mortality in patients with PC. However, no significant relation has been observed in RCTs. Therefore, it is necessary to be cautious in interpreting the results.

Predicting Ovarian-Cancer Burden in Catalonia by 2030: An Age-Period-Cohort Modelling

Ovarian cancer is the most lethal gynaecological cancer in very-high-human-development-index regions. Ovarian cancer incidence and mortality rates are estimated to globally rise by 2035, although incidence and mortality rates depend on the region and prevalence of the associated risk factors. The aim of this study is to assess changes in incidence and mortality of ovarian cancer in Catalonia by 2030. Bayesian autoregressive age–period–cohort models were used to predict the burden of OC incidence and mortality rates for the 2015–2030 period. Incidence and mortality rates of ovarian cancer are expected to decline in Catalonia by 2030 in women ≥ 45 years of age. A decrease in ovarian-cancer risk was observed with increasing year of birth, with a rebound in women born in the 1980s. A decrease in mortality was observed for the period of diagnosis and period of death. Nevertheless, ovarian-cancer mortality remains higher among older women compared to other age groups. Our study summarizes the most plausible scenario for ovarian-cancer changes in terms of incidence and mortality in Catalonia by 2030, which may be of interest from a public health perspective for policy implementation.

Challenges and Opportunities in the Statistical Analysis of Multiplex Immunofluorescence Data

Simple Summary

Immune modulation is considered a hallmark of cancer initiation and progression, and has offered promising opportunities for therapeutic manipulation. Multiplex immunofluorescence (mIF) technology has enabled the tumor immune microenvironment (TIME) to be studied at an increased scale, in terms of both the number of markers and the number of samples. Another benefit of mIF technology is the ability to measure not only the abundance but also the spatial location of multiple cells types within a tissue sample simultaneously, allowing for assessment of the co-localization of different types of immune markers. Thus, the use of mIF technologies have enable researchers to characterize patient, clinical, and tumor characteristics in the hope of identifying patients whom might benefit from immunotherapy treatments. In this review we outline some of the challenges and opportunities in the statistical analyses of mIF data to study the TIME.

Abstract

Immune modulation is considered a hallmark of cancer initiation and progression. The recent development of immunotherapies has ushered in a new era of cancer treatment. These therapeutics have led to revolutionary breakthroughs; however, the efficacy of immunotherapy has been modest and is often restricted to a subset of patients. Hence, identification of which cancer patients will benefit from immunotherapy is essential. Multiplex immunofluorescence (mIF) microscopy allows for the assessment and visualization of the tumor immune microenvironment (TIME). The data output following image and machine learning analyses for cell segmenting and phenotyping consists of the following information for each tumor sample: the number of positive cells for each marker and phenotype(s) of interest, number of total cells, percent of positive cells for each marker, and spatial locations for all measured cells. There are many challenges in the analysis of mIF data, including many tissue samples with zero positive cells or “zero-inflated” data, repeated measurements from multiple TMA cores or tissue slides per subject, and spatial analyses to determine the level of clustering and co-localization between the cell types in the TIME. In this review paper, we will discuss the challenges in the statistical analysis of mIF data and opportunities for further research.

Racial-Ethnic and Socioeconomic Disparities in Guideline-Adherent Treatment for Endometrial Cancer

OBJECTIVE

To evaluate the association of race-ethnicity and neighborhood socioeconomic status with adherence to National Comprehensive Cancer Network guidelines for endometrial carcinoma.

METHODS

Data are from the SEER (Surveillance, Epidemiology, and End Results) cancer registry of women diagnosed with endometrial carcinoma for the years 2006-2015. The sample included 83,883 women after inclusion and exclusion criteria were applied. Descriptive statistics, bivariate analyses, univariate, and multivariate logistic regression models were performed to evaluate the association between race-ethnicity and neighborhood socioeconomic status with adherence to treatment guidelines.

RESULTS

After controlling for demographic and clinical covariates, Black (odds ratio [OR] 0.89, P<.001), Latina (OR .92, P<.001), and American Indian or Alaska Native (OR 0.82, P=.034) women had lower odds of receiving adherent treatment and Asian (OR 1.14, P<.001) and Native Hawaiian or Pacific Islander (OR 1.19 P=.012) women had higher odds of receiving adherent treatment compared with White women. After controlling for covariates, there was a gradient by neighborhood socioeconomic status: women in the high-middle (OR 0.89, P<.001), middle (OR 0.84, P<.001), low-middle (OR 0.80, P<.001), and lowest (OR 0.73, P<.001) neighborhood socioeconomic status categories had lower odds of receiving adherent treatment than the those in the highest neighborhood socioeconomic status group.

CONCLUSIONS

Findings from this study suggest there are racial-ethnic and neighborhood socioeconomic disparities in National Comprehensive Cancer Network treatment adherence for endometrial cancer. Standard treatment therapies should not differ based on sociodemographics. Interventions are needed to ensure that equitable cancer treatment practices are available for all individuals, regardless of racial-ethnic or socioeconomic background.

Impact of Rurality on Stage IV Ovarian Cancer at Diagnosis: A Midwest Cancer Registry Cohort Study

PURPOSE

We aim to understand if rurality impacts patients' odds of presenting with stage IV ovarian cancer at diagnosis independent of distance to primary care provider and the socioeconomic status of a patient's residential census tract.

METHODS

A cohort of 1,000 women with ovarian cancer in Iowa, Kansas, and Missouri were sampled and analyzed from the cancer registries' statewide population data. The sample contained those with a histologically confirmed primary ovarian cancer diagnosis in 2011-2012. All variables were captured through an extension of standard registry protocol using standardized definitions and abstraction manuals. Chi-square tests and a multivariable logistic regression model were used.

FINDINGS

At diagnosis, 111 women in our sample had stage IV cancer and 889 had stage I-III. Compared to patients with stage I-III cancer, patients with stage IV disease had a higher average age, more comorbidities, and were more often living in rural areas. Multivariate analysis showed that rural women (vs metropolitan) had a greater odds of having stage IV ovarian cancer at diagnosis (odds ratio = 2.41 and 95% confidence interval = 1.33-4.39).

CONCLUSION

Rural ovarian cancer patients have greater odds of having stage IV cancer at diagnosis in Midwestern states independent of the distance they lived from their primary care physician and the socioeconomic status of their residential census tract. Rural women's greater odds of stage IV cancer at diagnosis could affect treatment options and mortality. Further investigation is needed into reasons for these findings.

Uterine cancer in breast cancer survivors: a systematic review

PURPOSE

Epidemiological evidence on the risk factors for uterine/endometrial cancer in breast cancer (BCa) survivors is limited and inconsistent. Therefore, we critically reviewed and summarized available evidence related to the risk factors for uterine/endometrial cancer in BCa survivors.

METHODS

We conducted a literature search through PubMed, Web of Science Core Collection/Cited Reference Search, as well as through manual searches of the bibliographies of the articles identified in electronic searches. We included in this review studies that were published up to November 30, 2018 that were accessible in full-text format and were published in English.

RESULTS

Of the 27 eligible studies, 96% had > 700 participants, 74% were prospective cohorts, 70% originated outside of the US, 44% reported as having pre-/postmenopausal women, and 26% reported having racially heterogeneous populations. Risk factors positively associated with uterine/endometrial cancer risk among BCa survivors included age at BCa diagnosis > 50 years, African American race, greater BMI/weight gain, and Tamoxifen treatment. For other lifestyle, reproductive and clinical factors, associations were either not significant (parity) or inconsistent (HRT use, menopausal status, smoking status) or had limited evidence (alcohol intake, family history of cancer, age at first birth, oral contraceptive use, age at menopause, comorbidities).

CONCLUSION

We identified several methodological concerns and limitations across epidemiological studies on potential risk factors for uterine/endometrial cancer in BCa survivors, including lack of details on uterine/endometrial cancer case ascertainment, varying and imprecise definitions of important covariates, insufficient adjustment for potential confounders, and small numbers of uterine/endometrial cancer cases in the overall as well as stratified analyses. Based on the available evidence, older age and higher body weight measures appear to be a shared risk factor for uterine/endometrial cancer in the general population as well as in BCa survivors. In addition, there is suggestive evidence that African American BCa survivors have a higher risk of uterine/endometrial cancer as compared to their White counterparts. There is also evidence that Tamoxifen contributes to uterine/endometrial cancer in BCa survivors. Given limitations of existing studies, more thorough investigation of these associations is warranted to identify additional preventive strategies needed for BCa survivors to reduce uterine/endometrial cancer risk and improve overall survival.

A Prospective Analysis of Circulating Plasma Metabolites Associated with Ovarian Cancer Risk

Ovarian cancer has few known risk factors, hampering identification of high-risk women. We assessed the association of prediagnostic plasma metabolites (N = 420) with risk of epithelial ovarian cancer, including both borderline and invasive tumors. A total of 252 cases and 252 matched controls from the Nurses' Health Studies were included. Multivariable logistic regression was used to estimate ORs and 95% confidence intervals (CI), comparing the 90th-10th percentile in metabolite levels, using the permutation-based Westfall and Young approach to account for testing multiple correlated hypotheses. Weighted gene coexpression network analysis (WGCNA; n = 10 metabolite modules) and metabolite set enrichment analysis (n = 23 metabolite classes) were also evaluated. An increase in pseudouridine levels from the 10th to the 90th percentile was associated with a 2.5-fold increased risk of overall ovarian cancer (OR = 2.56; 95% CI, 1.48-4.45; P = 0.001/adjusted P = 0.15); a similar risk estimate was observed for serous/poorly differentiated tumors (n = 176 cases; comparable OR = 2.38; 95% CI, 1.33-4.32; P = 0.004/adjusted P = 0.55). For nonserous tumors (n = 34 cases), pseudouridine and C36:2 phosphatidylcholine plasmalogen had the strongest statistical associations (OR = 9.84; 95% CI, 2.89-37.82; P < 0.001/adjusted P = 0.07; and OR = 0.11; 95% CI, 0.03-0.35; P < 0.001/adjusted P = 0.06, respectively). Five WGCNA modules and 9 classes were associated with risk overall at FDR ≤ 0.20. Triacylglycerols (TAG) showed heterogeneity by tumor aggressiveness (case-only heterogeneity P < 0.0001). The TAG association with risk overall and serous tumors differed by acyl carbon content and saturation. In summary, this study suggests that pseudouridine may be a novel risk factor for ovarian cancer and that TAGs may also be important, particularly for rapidly fatal tumors, with associations differing by structural features. SIGNIFICANCE: Pseudouridine represents a potential novel risk factor for ovarian cancer and triglycerides may be important particularly in rapidly fatal ovarian tumors.

Prediagnostic Leukocyte Telomere Length and Pancreatic Cancer Survival

BACKGROUND

Leukocyte telomere length has been associated with risk of subsequent pancreatic cancer. Few prospective studies have evaluated the association of prediagnostic leukocyte telomere length with pancreatic cancer survival.

METHODS

We prospectively examined the association of prediagnostic leukocyte telomere length with overall survival (OS) time among 423 participants diagnosed with pancreatic adenocarcinoma between 1984 and 2008 within the Health Professionals Follow-up Study, Nurses' Health Study, Physicians' Health Study, and Women's Health Initiative. We measured prediagnostic leukocyte telomere length in banked blood samples using quantitative PCR. Cox proportional hazards models were used to estimate HRs for OS with adjustment for potential confounders. We also evaluated 10 SNPs at the telomerase reverse transcriptase locus.

RESULTS

Shorter prediagnostic leukocyte telomere length was associated with reduced OS among patients with pancreatic cancer (P trend = 0.04). The multivariable-adjusted HR for OS comparing the lowest with highest quintiles of leukocyte telomere length was 1.39 (95% confidence interval, 1.01-1.93), corresponding to a 3-month difference in median OS time. In an analysis excluding cases with blood collected within 2 years of cancer diagnosis, the association was moderately stronger (HR, 1.55; 95% confidence interval, 1.09-2.21; comparing the lowest with highest quintiles; P trend = 0.01). No prognostic association or effect modification for the prognostic association of prediagnostic leukocyte telomere length was noted in relation to the studied SNPs.

CONCLUSIONS

Prediagnostic leukocyte telomere length was associated with pancreatic cancer survival.

IMPACT

Prediagnostic leukocyte telomere length can be a prognostic biomarker in pancreatic cancer.

Impact of Coexisting Uterine Adenomyosis on the Survival Outcome of Patients with Endometrial Cancer: A Retrospective Cohort Study

Objective:

To determine the effects of uterine adenomyosis on endometrial cancerrecurrence rates.

Methods:

This retrospective cohort study reviewed all consecutive patients diagnosed with endometrial cancerwho underwent total hysterectomy-based surgical staging at Srinagarind Hospital between January, 2010 and January, 2016. The patientswere divided into two groups:a uterine adenomyosisgroup and a non-adenomyosis group. Patient demographics, type of surgery, histopathology, stage of endometrial cancer, adjuvant treatment, and survival outcomes were compared.

Results:

A total 350 patients were enrolled, with 132 (37.71%) in the adenomyosis group and 218 (62.29%) in the non-adenomyosis group. Deep myometrial invasion and lymphovascular space invasion (LVSI) were more commonly found among patients who had no adenomyosis compared to those with adenomyosis(52.8% vs 39.4%, P=0.02 and 53.2% vs. 38.6%, P=0.01). There were no significant differences in terms of five-year recurrence-free survival (HR=1.47; 95%CI 0.88-2.44) and five-year overall survival (HR=0.81; 95%CI 0.43-1.53) between the two comparison groups.

Conclusion:

Coexisting uterine adenomyosis in endometrial cancer wasassociated withdeep myometrial invasion and LVSI but did not have significant impact on survival.

Social Integration, Marital Status, and Ovarian Cancer Risk: A 20-Year Prospective Cohort Study

OBJECTIVE

Low social integration and divorce/widowhood are chronic psychosocial stressors that may affect health. When assessed after cancer diagnosis, they have been associated with poorer survival, but their role in cancer development, particularly ovarian cancer (OvCA), is less understood. We investigated whether social integration and marital status were related to OvCA risk in a large population-based study.

METHODS

Women from the Nurses' Health Study completed the Berkman-Syme Social Network Index and reported their marital status every 4 years starting in 1992 (N = 72,206), and were followed up until 2012 (20-year follow-up period). Multivariate Cox regression models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) of OvCA risk, considering relevant potential confounders, in lagged analyses whereby psychosocial indicators were assessed 4 to 8 years (n = 436 cases) and 8 to 12 years (n = 306 cases) before diagnosis to account for the effects of prediagnostic symptoms on social measures. Secondary analyses evaluated the stability of and cumulative exposure to these social factors on OvCA risk.

RESULTS

Being socially isolated versus integrated was related to an increased OvCA risk 8 to 12 years later (HR = 1.51, 95% CI = 1.07-2.13), but not 4 to 8 years later. Compared with married women, OvCA risk was significantly higher in widowed but not in separated/divorced individuals, with both time periods (e.g., 8-12 years later: HRwidowed = 1.57 [95% CI = 1.15-2.14] versus HRseparated/divorced = 1.13 [95% CI = 0.74-1.72]). Estimates were comparable or stronger when investigating stability in and cumulative effects of social indicators.

CONCLUSIONS

Results suggest higher OvCA risk among socially isolated and widowed women, particularly when such psychosocial stressors were experienced a decade before diagnosis or were sustained over time.

Statin use and pancreatic cancer risk in two prospective cohort studies

BACKGROUND

Statins, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, are common lipid-lowering agents and may reduce the risk of several cancer types including pancreatic cancer. However, the association between statin use and pancreatic cancer risk has not been fully evaluated in prospective studies.

METHODS

We studied the association between statin use and incident pancreatic cancer in 113,059 participants from the prospective Nurses' Health Study and Health Professionals Follow-up Study. Statin use was self-reported via study questionnaires and updated biennially. Hazard ratios (HRs) and 95% confidence intervals (CIs) for incidence of pancreatic cancer were estimated using multivariable Cox proportional hazards models with adjustment for potential confounders.

RESULTS

In total, 583 participants developed incident pancreatic cancer during 1.4 million person-years of follow-up. No difference was identified in pancreatic cancer risk for regular versus non-regular statin users (multivariable-adjusted HR 0.98; 95% CI 0.82-1.16). There was no significant heterogeneity in the association of statin use with pancreatic cancer risk between the cohorts. Similarly, longer duration of regular statin use was not associated with decreased risk of pancreatic cancer (P_trend = 0.65). The results remained similar when we examined statin use status at baseline or accounting for 4-year latency period. We observed no statistically significant effect modification for the association of statin use with pancreatic cancer risk by body mass index, smoking status, or diabetes mellitus status (all P_interaction > 0.21).

CONCLUSIONS

Regular statin use was not associated with pancreatic cancer risk in two large prospective cohort studies in the U.S.

Prediagnosis Use of Statins Associates With Increased Survival Times of Patients With Pancreatic Cancer

BACKGROUND & AIMS

Statin medications, most commonly prescribed to reduce lipid levels and prevent cardiovascular disease, may be associated with longer survival times of patients with cancer. However, the association of statins with outcomes of patients with pancreatic adenocarcinoma is not clear.

METHODS

We analyzed the association of statin use before a diagnosis of pancreatic cancer with survival times of 648 participants in the Nurses' Health Study and Health Professionals Follow-up Study who were diagnosed with pancreatic adenocarcinoma from 2000 through 2013. We estimated hazard ratios (HRs) for overall mortality using Cox proportional hazards models with adjustment for potential confounders. We assessed the temporal association between prediagnosis statin use and cancer survival by 2-year lag periods to account for a possible latency period between statin use and cancer survival.

RESULTS

Regular statin use before diagnosis of pancreatic cancer was associated with modestly prolonged survival compared with nonregular use (adjusted HR, 0.82; 95% CI, 0.69-0.97; P = .02). A 1-month longer median survival was observed in regular statin users compared with nonregular users. Regular statin use within the 2 years prior to cancer diagnosis was most strongly associated with longer survival. We observed no statistically significant effect modification by smoking status, body mass index, diabetes, or cancer stage (all Pinteraction > .53). Regular statin use before diagnosis was similarly associated with survival in the Nurses' Health Study (HR, 0.79; 95% CI, 0.64-0.97) and Health Professionals Follow-up Study (HR, 0.86; 95% CI, 0.63-1.15).

CONCLUSIONS

Regular statin use before diagnosis of pancreatic cancer was associated with modest increases in survival times in 2 large prospective cohort studies.