Perineal talc exposure and epithelial ovarian cancer risk in the Central Valley of California

Intimate Care Products and Incidence of Hormone-Related Cancers: A Quantitative Bias Analysis

PURPOSE

Intimate care products may contain substances associated with increased risk of hormone-related cancers. The relationship between genital talc use and ovarian cancer, in particular, has been well studied, but concerns about recall bias and exposure misclassification have precluded conclusions. We examined the association between intimate care products and female hormone-related cancers, accounting for potential biases, using data from a US-based cohort study.

METHODS

The Sister Study enrolled 50,884 women who had a sister with breast cancer. Data on genital talc use and douching were collected at enrollment (2003-2009) and follow-up (2017-2019). We used Cox proportional hazards models to estimate hazard ratios (HRs) for associations between intimate care product use and breast, ovarian, and uterine cancers. To account for potential exposure misclassification and recall bias, we conducted quantitative bias analyses under various exposure reassignment assumptions.

RESULTS

Across considered scenarios, 41%-64% of participants douched and 35%-56% used genital talc. In models adjusted for exposure misclassification, genital talc use was positively associated with ovarian cancer (HR range, 1.17-3.34) Frequent douching and douching during young adulthood were positively associated with ovarian cancer, but neither douching nor talc was associated with breast or uterine cancer. Differential reporting of talc use by cases and noncases likely produces positive biases, but correcting for error still resulted in HRs above 1.0. For example, HR, 1.40 (95% CI, 1.04 to 1.89) when 25% of exposed cases and 10% of unexposed noncases had talc status reassigned.

CONCLUSION

Although results show how differential recall would upwardly bias estimates, corrected results support a positive association between use of intimate care products, including genital talc, and ovarian cancer.

A systematic review of the epidemiology evidence on talc and cancer

Over the past several decades, there have been many epidemiology studies on talc and cancer published in the scientific literature, and several reviews and meta-analyses of talc and respiratory, female reproductive, and stomach cancers, specifically. To help provide a resource for the evaluation of talc as a potential human carcinogen, we applied a consistent set of examination methods and criteria for all epidemiology studies that examined the association between talc exposure (by various routes) and cancers (of various types). We identified 30 cohort, 35 case-control, and 12 pooled studies that evaluated occupational, medicinal, and personal-care product talc exposure and cancers of the respiratory system, the female reproductive tract, the gastrointestinal tract, the urinary system, the lymphohematopoietic system, the prostate, male genital organs, and the central nervous system, as well as skin, eye, bone, connective tissue, peritoneal, and breast cancers. We tabulated study characteristics, quality, and results in a systematic manner, and evaluated all cancer types for which studies of at least three unique populations were available in a narrative review. We focused on study quality aspects most likely to impact the interpretation of results. We found that only one study, of medicinal talc use, evaluated direct exposure measurements for any individuals, though some used semi-quantitative exposure metrics, and few studies adequately assessed potential confounders. The only consistent associations were with ovarian cancer in case-control studies and these associations were likely impacted by recall and potentially other biases. This systematic review indicates that epidemiology studies do not support a causal association between occupational, medicinal, or personal talc exposure and any cancer in humans.

Systematic review of the association between talc and female reproductive tract cancers

Talc is a hydrous magnesium sheet silicate used in cosmetic powders, ceramics, paints, rubber, and many other products. We conducted a systematic review of the potential carcinogenicity of genitally applied talc in humans. Our systematic review methods adhere to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and incorporated aspects from the US Institute of Medicine (IOM, now the National Academy of Medicine) and several US EPA frameworks for systematic reviews, evaluating and integrating the epidemiological, animal, and mechanistic literature on talc and cancer. We conducted a comprehensive literature search. Detailed data abstraction and study quality evaluation, adapting the Toxic Substances Control Act (TSCA) framework, were central to our analysis. The literature search and selection process identified 40 primary studies that assessed exposure to talc and female reproductive cancer risks in humans (n = 36) and animals (n = 4). The results of our evaluation emphasize the importance of considering biological plausibility and study quality in systematic review. Integrating all streams of evidence according to the IOM framework yielded classifications of suggestive evidence of no association between perineal application of talcum powders and risk of ovarian cancer at human-relevant exposure levels. We also concluded that there is suggestive evidence of no association between genital talc application and endometrial cancer, and insufficient evidence to determine whether a causal association exists between genital talc application and cervical cancer based on a smaller but largely null body of literature.

Association Between the Frequent Use of Perineal Talcum Powder Products and Ovarian Cancer: a Systematic Review and Meta-analysis

BACKGROUND

Risk of ovarian cancer in women with frequent perineal talcum powder product is not well understood. Prior systematic reviews focused on ever use. The purpose of this study is to estimate the association between frequent (at least 2 times per week) perineal talcum powder use and ovarian cancer.

METHODS

A systematic review and meta-analysis was conducted according to meta-analysis of observational studies in epidemiology guidelines. Study protocol was prospectively registered at PROSPERO (registration number CRD42020172720). Searches were performed in PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials databases from their inception to August 2, 2021. Case-control and cohort studies were included if they reported frequent perineal talcum powder use and an adjusted odds ratio or hazard ratio for ovarian cancer. Review for inclusion, data extraction, and quality assessment (using the Newcastle-Ottawa Scale [NOS]) were performed independently by two reviewers. Pooled adjusted odds ratios with 95% confidence intervals were generated from the random effects model. Heterogeneity was quantified with I² statistic. Funnel plot and Eger's test were performed to assess publication bias. Subgroup and sensitivity analyses were performed for testing the robustness of the overall findings.

RESULTS

Initial database searches returned 761 unique citations and after review, eleven studies describing 66,876 patients, and 6542 cancers were included (Cohen's κ = 0.88). Publication quality was high (median NOS = 8, range: 4 to 9). Frequent talcum powder use was associated with an elevated risk of ovarian cancer (adjusted pooled summary odds ratio 1.47 (95% CI 1.31, 1.65, P<0.0001). There was no evidence of bias and low heterogeneity (I²= 24%, P=0.22). There was no meaningful difference limiting analysis to publications with a NOS quality score of 8 or 9 or limiting studies based on study design.

CONCLUSIONS

This review suggests an increased risk of ovarian cancer associated with frequent perineal powder exposure of 31-65%.

Talc, body powder, and ovarian cancer: A summary of the epidemiologic evidence

Many women apply powder to the genital area as a drying agent. Talc, an inert mineral with a high capacity to absorb water, has historically been a major component of body powders. Due to its similarity and co-occurrence with asbestos, the association of body powder/talc use and gynecological cancer risk, specifically ovarian cancer risk, has been a long-standing research question. Retrospective case-control studies have shown associations between genital powder use and ovarian cancer risk, with summary relative risk estimates from meta-analyses and pooled analyses ranging from 1.24 to 1.35 for ever versus never use. In contrast, prospective cohort studies have not shown a statistically significant association until recently, when a pooled analysis of four large cohorts demonstrated a weak, but statistically significant association among women with patent reproductive tracts (hazard ratio 1.13). Taken together, the epidemiological data from case-control studies and cohort studies suggest that there may be a small, positive association between genital powder use and ovarian cancer. The causal factors underlying this association are not clear. Proposed factors include talc, other minerals, such as asbestos or quartz, that are known carcinogens and may contaminate talc products, or other powder ingredients that could cause inflammation of the reproductive tracts. Given the rarity of ovarian cancer in the general population, the small increase in relative risk translates to a very low increase in absolute risk. Further research is needed to understand the underpinnings of the observed association between genital powder use and ovarian cancer risk.

Primary Ovarian Mesothelioma: A Case Series with Electron Microscopy Examination and Review of the Literature

Primary ovarian mesothelioma is a rare, aggressive neoplastic disease with a poor prognosis. At onset, the tumor is only rarely limited to the ovaries and usually already widespread in the peritoneum. The rarity of this entity and the difficulties differentiating it from either ovarian carcinoma or peritoneal mesothelioma may lead to frequent misdiagnoses and may raise some concerns about its histogenesis. Thus, reporting such rare cases is fundamental to gain greater awareness of this neoplasm and try to answer unsolved questions. Herein, we described four cases of histological diagnoses of ovarian mesothelioma extrapolated by the regional mesothelioma register of Apulia (southern Italy). In all cases, a detailed medical history was collected according to national mesothelioma register guidelines. A broad panel of antibodies was used for immunohistochemistry to confirm the diagnoses. Moreover, ovarian tissue samples were also examined by transmission and scanning electron microscopy, detecting asbestos fibers and talc crystals in two cases. Because of the few cases described, we reviewed the English literature in the Medline database, focusing on articles about ovarian mesothelioma "misclassification", "misdiagnosis", "diagnostic challenge" or "diagnostic pitfall" and on unsolved questions about its histogenesis and possible risk factors.

Serous Ovarian Cancer Caused by Exposure to Asbestos and Fibrous Talc in Cosmetic Talc Powders-A Case Series

OBJECTIVE

Asbestos is a known cause of ovarian cancer. We report 10 cases of serous ovarian cancer among users of Johnson & Johnson (J&J) asbestos-containing "cosmetic" talc products.

METHODS

We conducted an asbestos exposure assessment during talc application and analyzed surgical tissues and talc containers for asbestos and talc.

RESULTS

Talc was found in all cases and tremolite and/or anthophyllite asbestos was found in 8/10 cases. The asbestos fibers found in the "cosmetic" talc containers matched those found in tissues. We estimated inhaled asbestos dose ranged from 0.38 to 5.18 fiber years.

CONCLUSION

We provide evidence that the inhaled dose of asbestos/fibrous talc from "cosmetic" talc use causes ovarian cancer. The unique combination of the types of asbestiform minerals detected in cancerous tissue and "cosmetic" talc is a fingerprint for exposure to asbestos-containing talc.

A critical review of talc and ovarian cancer

The association between perineal talc use and ovarian cancer has been evaluated in several epidemiology studies. Some case-control studies reported weak positive associations, while other case-control and three large prospective cohort investigations found this association to be null. A weight-of-evidence evaluation was conducted of the epidemiology, toxicity, exposure, transport, in vitro, and mechanistic evidence to determine whether, collectively, these data support a causal association. Our review of the literature indicated that, while both case-control and cohort studies may be impacted by bias, the possibility of recall and other biases from the low participation rates and retrospective self-reporting of talc exposure cannot be ruled out for any of the case-control studies. The hypothesis that talc exposure induces ovarian cancer is only supported if one discounts the null results of the cohort studies and the fact that significant bias and/or confounding are likely reasons for the associations reported in some case-control investigations. In addition, one would need to ignore the evidence from animal experiments that show no marked association with cancer, in vitro and genotoxicity studies that did not indicate a carcinogenic mechanism of action for talc, and mechanistic and transport investigations that did not support the retrograde transport of talc to the ovaries. An alternative hypothesis that talc does not produce ovarian cancer, and that bias and confounding contribute the reported positive associations in case-control studies, is better supported by the evidence across all scientific disciplines. It is concluded that the evidence does not support a causal association between perineal talc use and ovarian cancer.

Data on systematic review and meta-analysis of epidemiologic evidence on the association between perineal use of talc powder and risk of ovarian cancer

This paper describes data from a systematic review and meta-analysis [1] conducted to identify and evaluate published peer reviewed evidence on the association between perineal use of talc powder and risk of ovarian cancer. These data were collected from multiple electronic bibliographic databases, as well as from grey literature sources, without applying time, language or other filters. A meta-analysis was conducted to quantitatively assess the ovarian cancer risk in relation to talc use and other potential risk factors.

The effect of talc particles on phagocytes in co-culture with ovarian cancer cells

Talc and titanium dioxide are naturally occurring water-insoluble mined products usually available in the form of particulate matter. This study was prompted by epidemiological observations suggesting that perineal use of talc powder is associated with increased risk of ovarian cancer, particularly in a milieu with higher estrogen. We aimed to test the effects of talc vs. control particles on the ability of prototypical macrophage cell lines to curb the growth of ovarian cancer cells in culture in the presence of estrogen. We found that murine ovarian surface epithelial cells (MOSEC), a prototype of certain forms of ovarian cancer, were present in larger numbers after co-culture with macrophages treated to a combination of talc and estradiol than to either agent alone or vehicle. Control particles (titanium dioxide, concentrated urban air particulates or diesel exhaust particles) did not have this effect. Co-exposure of macrophages to talc and estradiol has led to increased production of reactive oxygen species and changes in expression of macrophage genes pertinent in cancer development and immunosurveillance. These findings suggest that in vitro exposure to talc, particularly in a high-estrogen environment, may compromise immunosurveillance functions of macrophages and prompt further studies to elucidate this mechanism.

Migration of Talc From the Perineum to Multiple Pelvic Organ Sites

OBJECTIVES

Genital talc use is associated with increased risk for ovarian carcinoma in epidemiologic studies. Finding talc in pelvic tissues in women with ovarian carcinoma who have used talc is important in documenting exposure and assessing talc's biologic potential, but tissue-based morphology studies have been rarely reported.

METHODS

We report five patient cases with documented perineal talc use, each of whom had talc (by both polarized light and scanning electron microscopy) in multiple pelvic sites distant from the perineum. Six negative-exposure control patients were also analyzed.

RESULTS

Talc particles were found in exposed patients, typically within two or more of the following locations: pelvic region lymph nodes, cervix, uterine corpus, fallopian tubes, and ovaries.

CONCLUSIONS

Our report adds new insights into the biologic potential of talc and suggests additional anatomic sites that should be closely examined for talc by oncologic surgical pathologists in the setting of perineal talc use.

Critical review of the association between perineal use of talc powder and risk of ovarian cancer

Over the past four decades, there has been increasing concern that perineal use of talc powder, a commonly used personal care product, might be associated with an increased risk of ovarian cancer.

OBJECTIVES

To critically review all available human epidemiological data on the relationship between perineal use of talc powder and ovarian cancer, with consideration of other relevant experimental evidence.

METHODOLOGY

We identified 30 human studies for qualitative assessment of evidence, including 27 that were retained for further quantitative analysis.

RESULTS

A positive association between perineal use of talc powder and ovarian cancer was found [OR: 1.28 (95% CI: 1.20-1.37)]. A significant risk was noted in Hispanics and Whites, in women applying talc to underwear, in pre-menopausal women and in post-menopausal women receiving hormonal therapy. A negative association was noted with tubal ligation.

CONCLUSION

Perineal use of talc powder is a possible cause of human ovarian cancer.

A case of lung adenocarcinoma complicated by pulmonary talcosis occurring in a patient employed in the confectionery industry

A 73-year-old Japanese man, who worked at a confectionery company for more than 20 years, was diagnosed with a 28 mm nodular lesion in the superior lobe of the right lung by whole-body computed tomography examination. A biopsy revealed the presence of adenocarcinoma. With a diagnosis of a primary lung cancer, a right upper lobectomy was performed. A nodular lesion, 25 × 23 mm in size, was observed in the upper right lobe lung field, and was diagnosed histopathologically as a papillary adenocarcinoma. In addition, fibrous scars in the central part of the tumor showed numerous Langhans and/or foreign body giant cells, and histiocytic cells that had phagocytized numerous small transparent crystals, together with coal powder deposition. The extracted crystals were observed with a scanning electron microscope, and although plate-like structures were observed, ferruginous bodies suggestive of asbestos were not found. The crystals were demonstrated to be talc by powder X-ray diffraction. Herein, we investigated a case of lung adenocarcinoma in a patient with talcosis, with discussions based on a literature search. This collision of talcosis and lung adenocarcinoma adds to an increasing body of knowledge on an apparent association between talc and cancer cases.

Delineating Potential Transcriptomic Association with Organochlorine Pesticides in the Etiology of Epithelial Ovarian Cancer

Background

Recent studies have shown that there is an increased risk of Epithelial Ovarian Cancer (EOC) with Organochlorine Pesticides (OCPs). However, the alteration in the gene expression profile has not been explored so far. The goal of the present study is to understand the probable molecular mechanism of OCPs toxicity towards discovery of dysregulation of signaling pathway associated with differential gene expression and candidate transcriptomic set of markers in the pathophysiology of EOC in OCPs exposed population.

Methods

The OCP levels were estimated by gas chromatography and whole genome differential expression study was carried out using expression microarray and candidate genes were validated using Real time RT-PCR.

Results

Significant level of OCP residues such as β-hexachlorocyclohexane (β-HCH), Heptachlor, Heptachlor epoxide B (HTEB), dichlorodiphenyldichloroethylene (p'p'-DDE) and endosulfan-I was found between healthy and EOC patients. The transcriptome profile of several genes revealed regulation of various important cellular processes such as metabolism, inflammation, cytoskeleton dysregulation of TGF and WNT pathway in EOC cases with high OCPs.

Conclusion

This study provides the first evidence showing that differentially expressed genes and dysregulation of signaling pathways might be associated with significant level of OCPs exposure in ovary tissue of epithelial ovarian cancer patients. Moreover, significant correlation of these genes with OCPs revealed that OCPs exposure played vital role in dysregulation of related pathways in the etiology of EOC.

Douching, Talc Use, and Risk of Ovarian Cancer

BACKGROUND

Douching was recently reported to be associated with elevated levels of urinary metabolites of endocrine disrupting phthalates, but there is no literature on douching in relation to ovarian cancer. Numerous case-control studies of genital talc use have reported an increased risk of ovarian cancer, but prospective cohort studies have not uniformly confirmed this association. Behavioral correlation between talc use and douching could produce confounding.

METHODS

The Sister Study (2003-2009) enrolled and followed 50,884 women in the US and Puerto Rico who had a sister diagnosed with breast cancer. At baseline, participants were asked about douching and talc use during the previous 12 months. During follow-up (median of 6.6 years), 154 participants reported a diagnosis of ovarian cancer. We computed adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for ovarian cancer risk using the Cox proportional hazards model.

RESULTS

There was little association between baseline perineal talc use and subsequent ovarian cancer (HR: 0.73, CI: 0.44, 1.2). Douching was more common among talc users (odds ratio: 2.1, CI: 2.0, 2.3), and douching at baseline was associated with increased subsequent risk of ovarian cancer (HR: 1.8, CI: 1.2, 2.8).

CONCLUSIONS

Douching but not talc use was associated with increased risk of ovarian cancer in the Sister Study.

The Association Between Talc Use and Ovarian Cancer: A Retrospective Case-Control Study in Two US States

Supplemental Digital Content is available in the text.

Multiple studies of ovarian cancer and genital talc use have led only to consensus about possible carcinogenicity. Seeking greater clarity, we examined this association in 2,041 cases with epithelial ovarian cancer and 2,100 age- and-residence-matched controls.

Association between Body Powder Use and Ovarian Cancer: The African American Cancer Epidemiology Study (AACES)

BACKGROUND

Epidemiologic studies indicate increased ovarian cancer risk among women who use genital powder, but this has not been thoroughly investigated in African American (AA) women, a group with a high prevalence of use. We evaluate the relationship between use of genital powder and nongenital powder in invasive epithelial ovarian cancer (EOC).

METHODS

Subjects are 584 cases and 745 controls enrolled in the African American Cancer Epidemiology Study (AACES), an ongoing, population-based case-control study of EOC in AA women in 11 geographic locations in the United States. AA controls were frequency matched to cases on residence and age. Logistic regression was used to calculate ORs and 95% confidence intervals (CI) for associations between genital and nongenital powder exposure and EOC risk, controlling for potential confounders.

RESULTS

Powder use was common (62.8% of cases and 52.9% of controls). Genital powder was associated with an increased risk of EOC (OR = 1.44; 95% CI, 1.11-1.86) and a dose-response relationship was found for duration of use and number of lifetime applications (P < 0.05). Nongenital use was also associated with EOC risk, particularly among nonserous EOC cases (OR = 2.28; 95% CI, 1.39-3.74). An association between powder use and upper respiratory conditions suggests an enhanced inflammatory response may explain the association between body powder and EOC.

CONCLUSIONS

In a study of AA women, body powder use was significantly associated with EOC risk.

IMPACT

The results support that body powder is a modifiable risk factor for EOC among AA women. Cancer Epidemiol Biomarkers Prev; 25(10); 1411-7. ©2016 AACRSee related commentary by Trabert, p. 1369.

Safety Assessment of Talc as Used in Cosmetics

The Cosmetic Ingredient Review Expert Panel (Panel) assessed the safety of talc for use in cosmetics. The safety of talc has been the subject of much debate through the years, partly because the relationship between talc and asbestos is commonly misunderstood. Industry specifications state that cosmetic-grade talc must contain no detectable fibrous, asbestos minerals. Therefore, the large amount of available animal and clinical data the Panel relied on in assessing the safety of talc only included those studies on talc that did not contain asbestos. The Panel concluded that talc is safe for use in cosmetics in the present practices of use and concentration (some cosmetic products are entirely composed of talc). Talc should not be applied to the skin when the epidermal barrier is missing or significantly disrupted.

African Americans and Hispanics Remain at Lower Risk of Ovarian Cancer Than Non-Hispanic Whites after Considering Nongenetic Risk Factors and Oophorectomy Rates

BACKGROUND

Risk factors for invasive epithelial ovarian cancer (IEOC) among Hispanics and African Americans are understudied despite notable differences in incidence relative to non-Hispanic whites.

METHODS

We used multivariate logistic regression to examine parity, oral contraceptive use, tubal ligation, endometriosis, family history of ovarian cancer, and talc use and risk of IEOC among Hispanics (308 cases and 380 controls), African Americans (128 cases and 143 controls), and non-Hispanic whites (1,265 cases and 1,868 controls) using four case-control studies we conducted in Los Angeles County. We expressed each of these factors in the form of increasing risk and calculated population attributable risk percentage (PAR%) estimates for the six risk factors separately and jointly in the three groups.

RESULTS

The risk associations with these six well-accepted factors were comparable in the three groups. The significant racial/ethnic differences in the prevalence of these factors and differences in their oophorectomy rates explained 31% of the lower incidence in African Americans compared with non-Hispanic whites, but only 13% of the lower incidence in Hispanics. The PAR%s ranged from 27.5% to 31.0% for no tubal ligation, 15.9% to 22.2% for not using oral contraceptives, and 12.2% to 15.1% for using talc in the three groups.

CONCLUSIONS

All six risk factors are comparably important in the three groups. Differences in the prevalence of these factors and their oophorectomy rates explained approximately one third of the difference in incidence between African Americans and non-Hispanic whites.

IMPACT

Devising strategies to lessen the burden of IEOC will be applicable to all three racial/ethnic groups.

[Professional risk factors associated with the cancer of the ovary. Literature review]

The aim of this work was to review the available literature on occupational risk factors associated with ovarian cancer. A PubMed search was performed using an algorithm with the following search terms: ovary, ovarian, exposure, work, occupation. Relevant articles were selected through assessment of titles and abstracts as well as through the reference lists of related articles. A total of 54 studies were selected for this review, including 17 studies on asbestos exposure and risk of ovarian cancer and, 16 studies on other occupational factors (5 cohort studies and 11 case control studies). An increased risk of ovarian cancer has been reported for several occupations (teachers, administration employees, nurses, religious workers) and various industrial sectors (biomedical research, telephony industry, hairdresser and beautician, printing factories) with inconsistent results. Moreover, in many of these studies, individual risk factors of ovarian cancers were not considered. Despite methodological limitations of published studies, a significantly increased risk for ovarian cancer associated with asbestos exposure have been consistently reported.

Targeted immune therapy of ovarian cancer

Clinical outcomes, such as recurrence-free survival and overall survival, in ovarian cancer are quite variable, independent of common characteristics such as stage, response to therapy, and grade. This disparity in outcomes warrants further exploration and therapeutic targeting into the interaction between the tumor and host. One compelling host characteristic that contributes both to the initiation and progression of ovarian cancer is the immune system. Hundreds of studies have confirmed a prominent role for the immune system in modifying the clinical course of the disease. Recent studies also show that anti-tumor immunity is often negated by immune regulatory cells present in the tumor microenvironment. Regulatory immune cells also directly enhance the pathogenesis through the release of various cytokines and chemokines, which together form an integrated pathological network. Thus, in the future, research into immunotherapy targeting ovarian cancer will probably become increasingly focused on combination approaches that simultaneously augment immunity while preventing local immune suppression. In this article, we summarize important immunological targets that influence ovarian cancer outcome as well as include an update on newer immunotherapeutic strategies.

Perineal powder use and risk of ovarian cancer

BACKGROUND

Case-control studies have reported an increased risk of ovarian cancer among talc users; however, the only cohort study to date found no association except for an increase in serous invasive ovarian cancers. The purpose of this analysis was to assess perineal powder use and risk of ovarian cancer prospectively in the Women's Health Initiative Observational Study cohort.

METHODS

Perineal powder use was assessed at baseline by self-report regarding application to genitals, sanitary napkins, or diaphragms and duration of use. The primary outcome was self-reported ovarian cancer centrally adjudicated by physicians. Cox proportional hazard regression was used to estimate risk, adjusting for covariates, including person-time until diagnosis of ovarian cancer (n = 429), death, loss to follow-up, or September 17, 2012. All statistical tests were two-sided.

RESULTS

Among 61576 postmenopausal women, followed for a mean of 12.4 years without a history of cancer or bilateral oophorectomy, 52.6% reported ever using perineal powder. Ever use of perineal powder (hazard ratio [HR]adj = 1.06, 95% confidence interval [CI] = 0.87 to 1.28) was not associated with risk of ovarian cancer compared with never use. Individually, ever use of powder on the genitals (HRadj = 1.12, 95% CI = 0.92 to 1.36), sanitary napkins (HRadj = 0.95, 95% CI = 0.76 to 1.20), or diaphragms (HRadj = 0.92, 95% CI = 0.68 to 1.23) was not associated with risk of ovarian cancer compared with never use, nor were there associations with increasing durations of use. Estimates did not differ when stratified by age or tubal ligation status.

CONCLUSION

Based on our results, perineal powder use does not appear to influence ovarian cancer risk.

The immune system in the pathogenesis of ovarian cancer

Clinical outcomes in ovarian cancer are heterogeneous even when considering common features such as stage, response to therapy, and grade. This disparity in outcomes warrants further exploration into tumor and host characteristics. One compelling host characteristic is the immune response to ovarian cancer. While several studies have confirmed a prominent role for the immune system in modifying the clinical course of the disease, recent genetic and protein analyses also suggest a role in disease incidence. Recent studies also show that anti-tumor immunity is often negated by immune suppressive cells present in the tumor microenvironment. These suppressive immune cells also directly enhance the pathogenesis through the release of various cytokines and chemokines, which together form an integrated pathologic network. Thus, future research into immunotherapy targeting ovarian cancer will likely become increasingly focused on combination approaches that simultaneously augment immunity while preventing local immune suppression or by disrupting critical cytokine networks.

Genital powder use and risk of ovarian cancer: a pooled analysis of 8,525 cases and 9,859 controls

Genital powder use has been associated with risk of epithelial ovarian cancer in some, but not all, epidemiologic investigations, possibly reflecting the carcinogenic effects of talc particles found in most of these products. Whether risk increases with number of genital powder applications and for all histologic types of ovarian cancer also remains uncertain. Therefore, we estimated the association between self-reported genital powder use and epithelial ovarian cancer risk in eight population-based case-control studies. Individual data from each study were collected and harmonized. Lifetime number of genital powder applications was estimated from duration and frequency of use. Pooled ORs were calculated using conditional logistic regression matched on study and age and adjusted for potential confounders. Subtype-specific risks were estimated according to tumor behavior and histology. 8,525 cases and 9,859 controls were included in the analyses. Genital powder use was associated with a modest increased risk of epithelial ovarian cancer [OR, 1.24; 95% confidence interval (CI), 1.15-1.33] relative to women who never used powder. Risk was elevated for invasive serous (OR, 1.20; 95% CI, 1.09-1.32), endometrioid (OR, 1.22; 95% CI, 1.04-1.43), and clear cell (OR, 1.24; 95% CI, 1.01-1.52) tumors, and for borderline serous tumors (OR, 1.46; 95% CI, 1.24-1.72). Among genital powder users, we observed no significant trend (P = 0.17) in risk with increasing number of lifetime applications (assessed in quartiles). We noted no increase in risk among women who only reported nongenital powder use. In summary, genital powder use is a modifiable exposure associated with small-to-moderate increases in risk of most histologic subtypes of epithelial ovarian cancer.

Detection of toxic metals (lead and chromium) in talcum powder using laser induced breakdown spectroscopy

A laser induced breakdown spectroscopic (LIBS) system was developed using a 266 nm laser and a high-resolution spectrograph (Andor SR 500 i-A) to detect the trace levels of the highly toxic metals such as lead and chromium present in different brands of talcum powder available in the local market. The strongest atomic transition lines of lead (Pb) (405.7 nm) and chromium (Cr) (425.4 nm) were used as spectral markers to simultaneously detect lead and chromium. The LIBS system was calibrated for these two heavy metals, and the system was able to detect 15-20 parts per million (ppm) of lead and 20-30 ppm of chromium in the talcum powder sample. The limits of detection of the LIBS system were also estimated, and they are 1.96 and 1.72 ppm per million respectively for lead and chromium. This study is highly significant due to the use of cosmetic products that could affect the health of millions of people around the globe.

Perineal powder use and risk of endometrial cancer in postmenopausal women

BACKGROUND

Most known endometrial cancer risk factors involve genetics or exposure to unopposed estrogens; less is known about risk due to environmental exposures. While several studies have found an increased risk of ovarian cancer associated with perineal powder use, only two studies have addressed perineal powder use and endometrial cancer risk.

METHODS

We used Cox proportional hazards regression to examine the association between perineal powder use and endometrial cancer risk using the Women's Health Initiative Observational Study Research Materials obtained from the National Heart, Lung, and Blood Institute Biological Specimen and Data Repository Coordinating Center.

RESULTS

Of the 48,526 women in our primary analysis, 25,181 (52 %) reported ever use of perineal powder. During 364,134 person-years of follow-up, 447 participants were diagnosed with endometrial cancer. Ever use of perineal powder was not associated with increased risk of endometrial cancer (multivariable-adjusted hazard ratio, 1.06; 95 % confidence interval, 0.87-1.28). External use of powder on the genitals and/or on sanitary napkins was also not significantly associated with risk of endometrial cancer. However, use of powder on a diaphragm for twenty or more years was associated with a threefold increase in risk of endometrial cancer compared to women who never used perineal powder (multivariable-adjusted hazard ratio, 3.06; 95 % CI, 2.00-4.70).

CONCLUSIONS

Any duration of external use of perineal powder was not associated with increased risk of endometrial cancer; however, long-term use of powder on a diaphragm may increase the risk of endometrial cancer.

Use of talcum powder and endometrial cancer risk

PURPOSE

Use of talcum powder in the perineal area has been associated with an increased risk of ovarian cancer, and a recent cohort study found a positive association with endometrial cancer. We sought to confirm this association using data from the Australian National Endometrial Cancer Study (ANECS).

METHODS

ANECS was a population-based case-control study conducted from 2005 to 2007, in which 1,399 women with newly diagnosed histologically confirmed primary endometrial cancer and 740 control women provided risk factor information via telephone interview. Unconditional logistic regression was used to estimate odds ratios adjusting for potential confounders.

RESULTS

We found no significant association between ever use of talc in the perineal area (OR 0.88, 95% CI: 0.68-1.14) or upper body area (OR 0.90, 95% CI: 0.71-1.14) and risk of endometrial cancer. The results were similar when stratified by subtype. Composite variables combining frequency and duration of talc use were also not significantly associated with risk (any perineal area use p = 0.07 and any upper body use p = 0.49).

CONCLUSIONS

The absence of any increase in risk and the similarity of our results for talc use on the upper body and in the perineal area do not support the hypothesis that use of talc in the perineal area is associated with an increased risk of endometrial cancer. Our data do not confirm the positive association between perineal talc use and endometrial cancer observed in the only previous study.

Tubal ligation and the risk of ovarian cancer: review and meta-analysis

BACKGROUND

The reduction of ovarian cancer (OC) risk in women with a history of tubal ligation (TL) has been reported repeatedly, mostly on small populations. We have aimed to provide a critical overview of the studies available to date and to conduct a meta-analysis.

METHODS

There were 40 relevant studies identified. The studies were divided into two groups for strict and extended meta-analysis, respectively. Subgroup analysis was performed for age, time dependency since TL, histological types of OC and BReast CAncer (BRCA) mutation.

RESULTS

Meta-analysis of 13 strictly selected studies showed a reduced risk of epithelial OC by 34%. The protective effect of TL was confirmed even in a subgroup of women 10-14 years after the procedure. The risk reduction was confirmed for the endometrioid (RR = 0.40) and serous (RR = 0.73) cancers but not for mucinous.

CONCLUSIONS

The review of relevant articles, as well as the meta-analysis of selected studies, yields consistent data on a significant reduction of OC risk in women who had undergone TL. The results of this meta-analysis should provide an impulse for further research on the etiology of ovarian epithelial cancers, focusing particularly on the importance of retrograde transport of endometrial cells.

Perineal use of talcum powder and endometrial cancer risk

BACKGROUND

Several studies have reported a positive association between perineal use of talcum powder among adult women and ovarian cancer risk. However, the relationship between talcum powder use and other gynecologic malignancies such as endometrial cancer has not been examined, and little information is available on nonhormonal risk factors for endometrial cancer.

METHODS

Perineal use of talcum powder was assessed in 1982 in the Nurses' Health Study. Approximately 40% of women who responded to the questions about perineal use of talcum powder reported ever use. Cox proportional hazards models were used to estimate the incidence rate ratio of endometrial cancer and 95% confidence interval (CI), adjusted for body mass index and other potential confounders. We evaluated the relationship among all women and stratified by menopausal status.

RESULTS

Our analysis included 66,028 women with 599 incident cases of invasive endometrial adenocarcinoma diagnosed between 1982 and 2004. Although no association was observed overall, the association varied by menopausal status (P interaction=0.02) and a positive association was observed among postmenopausal women; ever use of talcum powder was associated with a 21% increase in risk of endometrial cancer (95% CI, 1.02-1.44), whereas regular use (at least once a week) was associated with a 24% increase in risk (95% CI, 1.03-1.48). In addition, we observed a borderline increase in risk with increasing frequency of use (P trend=0.04).

CONCLUSIONS

Our results suggest that perineal talcum powder use increases the risk of endometrial cancer, particularly among postmenopausal women.

IMPACT

Future and larger studies are needed to confirm this association and investigate potential mechanisms.

Risk factors for epithelial ovarian cancer by histologic subtype

Previous epidemiologic studies suggest that the major histologic subtypes of epithelial ovarian cancer may have different risk factor profiles; however, no known prospective study has systematically examined differences in risk by subtype. The authors used Cox proportional hazards regression, stratified by histologic subtype and time period, to examine the association between ovarian cancer risk factors and incidence of serous invasive, endometrioid, and mucinous ovarian cancers in the US Nurses' Health Study (1976-2006) and Nurses' Health Study II (1989-2005). For each exposure, they calculated P-heterogeneity using a likelihood ratio test comparing models with separate estimates for the 3 subtypes versus a single estimate across subtypes. Analysis included 221,866 women and 721 cases with the histologies of interest (496 serous invasive, 139 endometrioid, 86 mucinous). In analyses of reproductive/hormonal exposures, the associations with age, duration of breastfeeding, age at natural menopause, and duration of estrogen use differed significantly by subtype (all P-heterogeneity < or =0.05). The associations with several nonreproductive exposures also appeared to vary by subtype, but only the association with smoking differed significantly (P-heterogeneity = 0.03). Results suggest that associations with several ovarian cancer risk factors vary by subtype, and these differences are consistent with known similarities between each major histologic subtype and its normal tissue counterpart.

Current understanding of risk factors for ovarian cancer

OPINION STATEMENT

Ovarian cancer is the deadliest gynecologic cancer. Unlike many cancers such as breast, cervical and colon cancers, there is no easily clinically identifiable pre-malignant phase of this malignancy making early identification difficult. Similarly, unlike lung, head and neck, and skin cancers, there is not easily identifiable risk factor making prevention short of oophorectomy difficult. Even so, theories as to the causative factors of ovarian cancer continue to evolve making our understanding of the genesis of ovarian cancer more clear. Genetics, parity, environment, hormonal factors, and inflammation all play an important and pivotal role in the development of ovarian cancer. The most current understanding of these elements and their respective contribution to the development of this cancer are presented in this chapter.

Epidemiological and genetic factors associated with ovarian cancer

The purpose of this article was to provide a comprehensive review of the epidemiological and genetic factors associated with ovarian cancer. A more complete understanding of the determinants of ovarian cancer may lead to the development of better screening and detection methods for this disease. The first section of this article reviews current literature on screening and early detection of ovarian cancer. The second section reviews the epidemiology of ovarian cancer, specifically highlighting the risk factors associated with the development of this disease. The article concludes with a discussion of how oncology nurses can apply this information to improve patient care.

Markers of inflammation and risk of ovarian cancer in Los Angeles County

Factors that increase inflammation have been suggested to influence the development of ovarian cancer, but these factors have not been well studied. To further investigate this question, we studied the role of talc use, history of endometrioisis and use of non-steroidal anti-inflammatory drugs (NSAIDs) and risk of ovarian cancer in a population-based case-control study in Los Angeles County involving 609 women with newly diagnosed epithelial ovarian cancer and 688 population-based control women. Risk of ovarian cancer increased significantly with increasing frequency and duration of talc use; compared to never users risk was highest among long-duration (20+ years), frequent (at least daily) talc users (adjusted relative risk (RR) = 2.08, 95% confidence interval (CI) = 1.34-3.23). A history of physician-diagnosed endometriosis was statistically significantly associated with risk (RR = 1.66, 95% CI = 1.01-2.75). Women who were talc users and had a history of endometriosis showed a 3-fold increased risk (RR = 3.12, 95% CI = 1.36-7.22). Contrary to the hypothesis that risk of ovarian cancer may be reduced by use of NSAIDs; risk increased with increasing frequency (per 7 times/week, RR = 1.27, 95% CI = 1.14-1.43) and years of NSAID use (per 5 years of use, RR = 1.25, 95% CI = 1.10-1.42); this was consistent across types of NSAIDs. We conclude that risk of ovarian cancer is significantly associated with talc use and with a history of endometriosis, as has been found in previous studies. The NSAID finding was unexpected and suggests that factors associated with inflammation are associated with ovarian cancer risk. This result needs confirmation with careful attention to the reasons for NSAID use.

Talc use, variants of the GSTM1, GSTT1, and NAT2 genes, and risk of epithelial ovarian cancer

Epidemiologic evidence suggests a possible association between genital use of talcum powder and risk of epithelial ovarian cancer; however, the biological basis for this association is not clear. We analyzed interactions between talc use and genes in detoxification pathways [glutathione S-transferase M1 (GSTM1), glutathione S-transferase T1 (GSTT1), and N-acetyltransferase 2 (NAT2)] to assess whether the talc/ovarian cancer association is modified by variants of genes potentially involved in the response to talc. Our analysis included 1,175 cases and 1,202 controls from a New England-based case-control study and 210 cases and 600 controls from the prospective Nurses' Health Study. We genotyped participants for the GSTM1 and GSTT1 gene deletions and three NAT2 polymorphisms. We used logistic regression to analyze the main effect of talc use, genotype, and gene-talc interactions in each population and pooled the estimates using a random-effects model. Regular talc use was associated with increased ovarian cancer risk in the combined study population (RR, 1.36; 95% CI, 1.14-1.63; P(trend) < 0.001). Independent of talc, the genes examined were not clearly associated with risk. However, the talc/ovarian cancer association varied by GSTT1 genotype and combined GSTM1/GSTT1 genotype. In the pooled analysis, the association with talc was stronger among women with the GSTT1-null genotype (P(interaction) = 0.03), particularly in combination with the GSTM1-present genotype (P(interaction) = 0.03). There was no clear evidence of an interaction with GSTM1 alone or NAT2. These results suggest that women with certain genetic variants may have a higher risk of ovarian cancer associated with genital talc use. Additional research is needed on these interactions and the underlying biological mechanisms.

Occupational exposures and ovarian cancer in textile workers

BACKGROUND

Occupational risk factors for ovarian cancer have been investigated only to a limited extent. We conducted a case-cohort study to examine associations between occupational exposures and ovarian cancer in the textile industry.

METHODS

We compared 261 incident ovarian cancer cases diagnosed between 1989 and 1998 with an age-stratified reference subcohort (n = 3199) from a cohort of 267,400 textile workers in Shanghai, China. Occupational exposures were assessed by job-exposure matrices designed for the textile industry, and estimates of quantitative cotton dust and endotoxin. We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) with Cox proportional hazards modeling adapted for the case-cohort design.

RESULTS

A decreased risk of ovarian cancer was associated with ever having worked in cotton manufacturing production (HR = 0.7; 95% CI = 0.4-1.0). An increased risk was associated with ever having worked in textile finishing (2.1; 0.9-5.0). We found an increasing risk of ovarian cancer associated with cumulative exposure to silica dust (for <10 years exposure, HR = 6.8 [CI = 0.6-76]; for > or =10 years, 5.6 [1.3-23.6]), although these results are based on only 8 exposed subcohort women (0.3%) and 4 cases (1.3%). We also detected inverse risk gradients for cumulative exposures to endotoxin when exposures were lagged by 20 years (in highest quartile, HR = 0.6 [CI = 0.4-1.1]).

CONCLUSION

Silica dust may increase the risk of ovarian cancer, and cotton dust and endotoxin may reduce risk.

Perineal talc use and ovarian cancer: a critical review

Talc, like asbestos, is a silicate that has been studied in relation to cancer risk. Several studies conducted over the past 25 years found an association between perineal talc powders and ovarian cancer. The summary relative risk is about 1.3 (95% confidence intervals 1.2-1.5) and these data have been interpreted as supporting a causal role. In this review article, we discuss the chemical and morphological features of talc and asbestos, and explain why despite their similar chemical classification talc does not possess asbestos-like carcinogenic properties. The heterogeneity in the perineal dusting studies has raised important concerns over the validity of the exposure measurements, and the lack of a consistent dose-response effect limits making causal inferences. Perhaps more importantly, whereas it is unknown whether external talc dust enters the female reproductive tract, measures of internal talc exposure such as talc-dusted diaphragms and latex condoms show no relationship with ovarian cancer risk. In addition, the therapeutic use of high dose cosmetic grade talc for pleurodesis has not been shown to cause cancer in patients receiving these treatment modalities. Talc is not genotoxic. Mechanistic, pathology and animal model studies have not found evidence for a carcinogenic effect. In summary, these data collectively do not indicate that cosmetic talc causes ovarian cancer.

Ovarian cancer hormonal and environmental risk effect

To understand the influence of hormonal and environmental factors on the risk of ovarian cancer, it is important to remember the established risk factors and postulated mechanisms that lead to the development of ovarian cancer. Several risk factors have been identified as increasing the risk of epithelial ovarian cancer, including low pariety, infertility, early age of menarche, and late age of menopause. This article discusses the different hypotheses and focuses on hormonal and environmental risk factors, as well the chemoprevention of epithelial ovarian cancer.

Talcum powder, chronic pelvic inflammation and NSAIDs in relation to risk of epithelial ovarian cancer

Chronic inflammation has been proposed as the possible causal mechanism that explains the observed association between certain risk factors, such as the use of talcum powder (talc) in the pelvic region and epithelial ovarian cancer. To address this issue we evaluated the potential role of chronic local ovarian inflammation in the development of the major subtypes of epithelial ovarian cancer. Factors potentially linked to ovarian inflammation were examined in an Australia-wide case-control study comprising 1,576 women with invasive and low malignant potential (LMP) ovarian tumours and 1,509 population-based controls. We confirmed a statistically significant increase in ovarian cancer risk associated with use of talc in the pelvic region (adjusted odds ratio 1.17, 95% CI: 1.01-1.36) that was strongest for the serous and endometrioid subtypes although the latter was not statistically significant (adjusted odds ratios 1.21, 95% CI 1.03-1.44 and 1.18, 95% CI 0.81-1.70, respectively). Other factors potentially associated with ovarian inflammation (pelvic inflammatory disease, human papilloma virus infection and mumps) were not associated with risk but, like others, we found an increased risk of endometrioid and clear cell ovarian cancer only among women with a history of endometriosis. Regular use of aspirin and other nonsteroidal anti-inflammatory drugs was inversely associated with risk of LMP mucinous ovarian tumours only. We conclude that on balance chronic inflammation does not play a major role in the development of ovarian cancer.

Asbestos fibers in ovarian tissue from Norwegian pulp and paper workers

An elevated risk of ovarian cancer has been observed in Norwegian pulp and paper workers who were possibly occupationally exposed to asbestos. The present study was initiated to investigate if the increased risk could be associated with asbestos fibers in ovarian tissue from workers in this industry. Normal ovarian tissue specimens from three groups of women were included in the study. The case group included specimens from 46 women diagnosed with ovarian cancer in the period 1953-2000, and who had been working in one or more pulp and paper mills between 1920 and 1993. Normal ovarian tissue specimens from two control groups without occupational history from pulp and paper work were selected from the Cancer Registry database. Tissue blocks were digested and prepared for transmission electron microscopy. Number of fibers per gram wet weight was calculated. Asbestos fibers were found in normal ovarian tissue from two subjects in the case group, while no fibers were found in the control groups. The two asbestos positive cases had been working as paper sorter/packer and chlorine plant worker, respectively. Both were possibly secondary exposed to asbestos from family members working as insulators. We conclude that the findings in this study did not allow drawing any firm conclusion about an association between occupational exposure to asbestos and ovarian cancer in Norwegian pulp and paper workers. Our study confirms that asbestos fibers may reach the ovaries and demonstrates that the applied method is appropriate for identification of the fibers.