talcum powder and cancer

http://www.cancer.org/cancer/cancercauses/othercarcinogens/athome/talcum-powder-and-cancer

"For any individual woman, if there is an increased risk, the overall increase is likely to very be small. Still, talc is widely used in many products, so it is important to determine if the increased risk is real. Research in this area continues."

"Until more information is available, people concerned about using talcum powder may want to avoid or limit their use of consumer products that contain it."

"추가적인 정보가 나타날때까지 탈컴 가루 사용이 걱정스러운 사람들은 그것을 포함하는 소비재의 사용을 피하거나 제한하기를 원할 수 있다."

이게 탈컴 가루에 대한 미국암협회의 공식적인 견해이고, 2016년 5월 3일에 개정되었다.

http://www.theguardian.com/lifeandstyle/2016/feb/29/is-it-safe-to-use-talcum-baby-powder-ovarian-cancer-johnson-johnson

Last year, a court awarded a woman in California $13m for developing a mesothelioma (a tumour of the lining of the lungs) from using talc with asbestos in it – the tiny fibres in talc are easily inhaled. Removing the asbestos, however, did not stop some studies continuing to link talc with ovarian cancer. A 2003 meta-analysis looking at 16 studies involving 11,933 women found talc was associated with a higher risk of ovarian cancer, but a 2014 study of 61,576 women found no such link. The International Agency for Research on Cancer (part of the WHO) has classified talc applied to the genitals as “possibly carcinogenic”. The studies that have found the weak links have been case-control studies that compare the use of talc by women with ovarian cancer to those without it. They rely on self-reported talc use, which is not terribly reliable.

몇달전의 가디안 기사가 그래도 좀 차분하다.

난소암의 위험이 증가한다는 논문을 언급하고 있어서 찾아보았다.

http://www.ncbi.nlm.nih.gov/pubmed/12820486

Perineal application of cosmetic talc and risk of invasive epithelial ovarian cancer: a meta-analysis of 11,933 subjects from sixteen observational studies.
Huncharek M1, Geschwind JF, Kupelnick B.Author informationAbstract
OBJECTIVE:
Prior epidemiological studies suggest an association between perineal cosmetic talc use and increased risk of epithelial ovarian cancer. A meta-analysis was performed to evaluate this suspected association.MATERIALS AND METHODS:
Using previously described methods, a protocol was developed for a meta-analysis examining the association between perineal talc use versus non-use and the development of invasive epithelial ovarian cancer. Literature search techniques, study inclusion criteria and statistical procedures were prospectively defined. Data from observational studies were pooled using a general variance based meta-analytic method employing confidence intervals previously described by Greenland. The outcome of interest was a summary relative risk (RRs) reflecting the risk of ovarian cancer development associated with perineal talc use versus non-use. Sensitivity analyses were performed when necessary to explain any observed statistical heterogeneity.RESULTS:
Sixteen observational studies meeting protocol specified inclusion criteria were located via a comprehensive literature search. These studies enrolled a total of 11,933 subjects. Analysis for heterogeneity demonstrated that the data were homogenous (p = 0.17) and could be combined in a meta-analysis. Pooling all sixteen studies yielded a RRs of 1.33 (CI = 1.16-1.45), a statistically significant result suggesting a 33% increased risk of ovarian cancer with perineal talc use. Despite this finding, the data showed a lack of a clear dose-response relationship making the RRs of questionable validity. Further sensitivity analyses showed that hospital-based studies showed no relationship between talc use and ovarian cancer risk, i.e. RRs 1.19 (0.99-1.41) versus population-based studies (RRs = 1.38, CI = 1.25-1.52). This suggests that selection bias and/or uncontrolled confouding may result in a spurious positive association between talc use and ovarian cancer risk in population-based studies.CONCLUSION:
The available observational data do not support the existence of a causal relationship between perineal talc exposure and an increased risk of epithelial ovarian cancer. Selection bias and uncontrolled confouding may account for the positive associations seen in prior epidemiological studies.

통계적으로 난소암의 위험이 33% 증가한다는 결과가 나왔지만, 이런저런 이유로 인과관계의 존재를 지지하지 않는다는 것이다.

http://www.ncbi.nlm.nih.gov/pubmed/25214560

Perineal powder use and risk of ovarian cancer.
Houghton SC1, Reeves KW1, Hankinson SE1, Crawford L1, Lane D1, Wactawski-Wende J1, Thomson CA1, Ockene JK1, Sturgeon SR2.
Author information

Abstract
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.

탈컴 가루 사용이 난소암 위험에 영향을 준 것으로 보이지 않는다는 것이다.


두 논문이 관련된 가장 광범위한 연구로 보이고 이런 수준의 증거가 있으면 난소암의 책임을 기업에 지우는 것은 내 생각에는 완전히 정신나간 짓이다.

징벌적 배상에 대한 판결을 내린 일부 주 법원의 판결은 창조론을 학교에서 가르치려고 끊임없이 시도하는 일부 주들의 결정과 일맥상통하는 듯하다.

과학적 상식이 부족한 배심원들이 인종적, 계급적, 감정적 결론을 내리는 미국 배심원 제도의 한계도 보여주는 듯하다. oj심슨사건, 애플디자인 특허 등.

미주리주에 대해 조사해본 적 없으나 트럼프를 극렬 지지한다는 남부, 저소득, 보수, 백인 하류층과 관련성도 의심된다.

나는 상급심에서 뒤집히거나 제한될 가능성이 높다고 본다.

또 이런 미국의 병적인 판결을 한국의 문제와 관련해 무슨 교과서적인 지침인 것처럼 언급하는 것은 누구에게도 득이 되지 않을 것으로 본다.