Cure fraction model with random effects for regional variation in cancer survival

Assessing regional differences in the survival of cancer patients is important but difficult when separate regions are small or sparsely populated. In this paper, we apply a mixture cure fraction model with random effects to cause‐specific survival data of female breast cancer patients collected by the population‐based Finnish Cancer Registry. Two sets of random effects were used to capture the regional variation in the cure fraction and in the survival of the non‐cured patients, respectively. This hierarchical model was implemented in a Bayesian framework using a Metropolis‐within‐Gibbs algorithm. To avoid poor mixing of the Markov chain, when the variance of either set of random effects was close to zero, posterior simulations were based on a parameter‐expanded model with tailor‐made proposal distributions in Metropolis steps. The random effects allowed the fitting of the cure fraction model to the sparse regional data and the estimation of the regional variation in 10‐year cause‐specific breast cancer survival with a parsimonious number of parameters. Before 1986, the capital of Finland clearly stood out from the rest, but since then all the 21 hospital districts have achieved approximately the same level of survival. Copyright © 2010 John Wiley & Sons, Ltd.     

人源性宫颈癌、子宫内膜癌、卵巢癌异种移植动物模型的建立

目的构建人来源的宫颈癌(cervical cancer,CC)、子宫内膜癌(endometrial cancer,EC)、卵巢癌(ovarian cancer,OC)人源性肿瘤异种移植动物模型,为研究和开发新药及个体化治疗提供实验模型。方法收集2018年2月至2019年4月新疆医科大学第一附属医院CC、EC、OC患者各5例的新鲜手术切除标本,移植至重度免疫缺陷(immunodeficiency,NOG)小鼠和非肥胖糖尿病/重症联合免疫缺陷(non-obese diabetes/severe combined immunodeficiency,NOD/SCLD)小鼠皮下,监测荷瘤小鼠体重和肿瘤体积,对长至500~1 000 mm^3大小的肿瘤进行传代移植,通过苏木精-伊红染色法(hematoxylin-eosin staining,HE)染色及免疫组化(immunohistochemistry,IHC)验证移植肿瘤组织与患者肿瘤组织的病理学一致性。结果本研究收集并移植15例CC、EC、OC肿瘤标本,成功构建CC、EC、OC PDX模型8例,建模成功率为53%。结论模型较好地保留了原发肿瘤的特征,为后续研究开发CC、EC、OC新的治疗方案、临床药物筛选以及个体化治疗提供了实验平台。     

Persisting risk of nickel related lung cancer and nasal cancer among Clydach refiners

Objective

To evaluate the risk of lung cancer and nasal cancer among workers employed at the Clydach nickel refinery, South Wales since 1930 by combining data from the two most recently published papers on this cohort.

Methods

Observed and expected numbers of cancer deaths were extracted for workers who had a minimum of five years service and were employed for the first time between 1902 and 1992. Standardised mortality ratios (SMR) were calculated for subgroups according to year of employment, time since first employment, and process work.

Results

A persisting excess of respiratory cancer was found for workers employed in the period 1930–92, with a lung cancer SMR of 133 (95% CI 103 to 172) and a SMR for nasal cancer of 870 (95% CI 105 to 3141). The lung cancer excess was most clearly seen 20 years or more after first employment and seemed to be confined to process workers. There was no indication of a further reduction in risk since 1930.

Conclusion

The extreme nickel related cancer hazard at the refinery before 1920 was greatly reduced during subsequent years. Some of the carcinogenic exposures seem to have remained after 1930, producing an elevated risk of nasal cancer and a 30% excess of lung cancer in the workforce. There was evidence of a persisting risk among process workers first employed since 1953.     

Estimating multilevel regional variation in excess mortality of cancer patients using integrated nested Laplace approximation

Models of excess mortality with random effects were used to estimate regional variation in relative or net survival of cancer patients. Statistical inference for these models based on the Markov chain Monte Carlo (MCMC) methods is computationally intensive and, therefore, not feasible for routine analyses of cancer register data. This study assessed the performance of the integrated nested Laplace approximation (INLA) in monitoring regional variation in cancer survival. Poisson regression model of excess mortality including both spatially correlated and unstructured random effects was fitted to the data of patients diagnosed with ovarian and breast cancer in Finland during 1955-2014 with follow up from 1960 through 2014 by using the period approach with five-year calendar time windows. We estimated standard deviations associated with variation (i) between hospital districts and (ii) between municipalities within hospital districts. Posterior estimates based on the INLA approach were compared to those based on the MCMC simulation. The estimates of the variation parameters were similar between the two approaches. Variation within hospital districts dominated in the total variation between municipalities. In 2000-2014, the proportion of the average variation within hospital districts was 68% (95% posterior interval: 35%-93%) and 82% (60%-98%) out of the total variation in ovarian and breast cancer, respectively. In the estimation of regional variation, the INLA approach was accurate, fast, and easy to implement by using the R-INLA package.     

肺癌及癌旁组织中微量元素含量分析

目的 :探讨肺癌患者的癌、癌旁和正常组织中微量元素含量的变化。方法 :收集 2 0例肺癌患者癌组织、癌旁组织及正常组织 ,用等离子体发射光谱仪测定Se、Zn、Cu、Fe、Mg、Mn含量。结果 :肺癌患者的正常组织、癌旁组织、癌组织Se、Zn、Mg的含量和Se/Zn的比值逐渐降低 ,但Cu、Fe、Mn的含量和Cu/Zn、Fe/Zn、Mn/Zn的比值则相反而逐渐升高 (P <0 .0 1)。结论 :微量元素含量的变化与肺癌发生、发展有一定的关系 ,对癌变过程的研究和临床治疗的指导具有重要意义     

Participation of regional inhabitants in cancer screening

As part of the strategic planning for increasing participation by community residents in cancer screening, a survey about life style and attitudes toward cancer screening was carried out in Samukawa town, Kanagawa Prefecture. Subjects were males 40 years old or over, and females 30 years old or over selected by random sampling from residents. Number of subjects was 1,916 (822 males, 1,094 females). Self administered anonymous questionnaires were sent and returned by mail. The response rate was 73%. The results were as follows: (1) The reported participation rates for cancer screening under "the Health and Medical Services Law for the Aged" did not reflect the actual participation rate of residents. (2) The major reason for not participation in screening was lack of interest in cancer prevention. (3) Socio-economic status of regular participants in screening was different from persons who did not participate. (4) Persons who did not participate in screening were more passive with regard to obtaining knowledge of cancer than regular participants. (5) Results of this study show that cancer prevention education at various levels such as by clinical offices, TV and radio programs, and newspapers may be effective. In order to increase participation in screening programs, health education that considers the life style characteristics of persons who do not participate in the screening programs is vitally important.     

Breast cancer screening in regional Hispanic populations

Although Hispanics' use of breast cancer screening services has been investigated, to date there have been no published studies of distinct Hispanic populations in different areas of the country. Using the diverse populations and sites involved in the National Hispanic Leadership Initiative on Cancer 'En Acción', this study examines ethno-regional differences in breast cancer screening rates among these groups and explores the correlates of screening participation. Data collected through telephone surveys were analyzed for women 40 years of age and older (n = 2082). After controlling for demographic variables traditionally related to breast cancer screening rates, it was found that ethno-regional differences in breast cancer screening practices clearly persisted. In addition to traditional demographic factors, other variables evidently underlie differences in Hispanics' utilization of breast cancer screening services. These variables may be cultural and should be investigated in future research. Meanwhile, researchers should not refer to the 'Hispanic' population at large without identifying, addressing and clarifying the ethno-regional characteristics of their samples.     

Formaldehyde and cancer: a critical review

Formaldehyde is a naturally occurring chemical found in every human cell. It has been in widespread use for over a century as a disinfectant and preservative agent, and more recently in a number of industrial products. Animal studies indicate that formaldehyde is a rat carcinogen at high levels (>_ 10 ppm) of exposure. Results for lower levels of exposure show less clear-cut carcinogenic effects, and some species, such as mice and hamsters, appear much less sensitive to any carcinogenic potential of formaldehyde. Epidemiologic studies of the effects of formaldehyde exposure among humans provide inconsistent results. In general, these nonexperimental studies suffer from a number of biases and flaws. The epidemiologic studies fall into three categories: formaldehyde industry workers, case-control studies, and studies of professionals who use formaldehyde. Studies of industry workers with known exposure to formaldehyde report little evidence of an excess cancer risk. Nasopharyngeal cancer, the one cancer considered most strongly linked to formaldehyde among humans, appears after close examination to be likely a result of multiple subgroup analyses and misclassification. The case-control studies usually lack any direct measure of formaldehyde exposure and rely instead on hypothetical exposure based on occupational exposure matrices. Most of these studies, after adjustment for confounding factors, fail to find a significant association with putative formaldehyde exposure. The studies that do report a significant association suffer from methodologic problems limiting their interpretation. The investigations of professionals who use formaldehyde in their work, such as embalmers, pathologists, and anatomists, have the advantage over case-control studies of a much higher likelihood of actual formaldehyde exposure. The findings among these individuals, however, are at odds with those of the other two groups, with excesses of deaths from cancer of the brain and leukemia. The inconsistency between professionals and formaldehyde industry workers in cancer risk patterns suggest that formaldehyde is not the etiologic agent. When the epidemiologic data on formaldehyde and human cancer are examined in light of the widely accepted causal criteria of strength of the association, consistency and specificity of results, dose-response effects, and biologic coherence and plausibility, the studies published so far fail to provide credible causal evidence.     

Oropharyngeal cancer epidemic and human papillomavirus

A growing body of research shows that human papillomavirus (HPV) is a common and increasing cause of oropharyngeal squamous cell carcinoma (OSCC). Thus, the International Agency for Research against Cancer has acknowledged HPV as a risk factor for OSCC, in addition to smoking and alcohol consumption. Recently, in Finland, the United Kingdom, the Netherlands, the United States, and Sweden, incidence of OSCC has increased, and an increase in the proportion of HPV-positive tumors was noted. On the basis of these data and reports indicating that patients with HPV-positive cancer have their first sexual experience at a young age and have multiple partners, we postulate that increased incidence of OSCC in the United States and some countries in northern Europe is because of a new, primarily sexually transmitted HPV epidemic. We also suggest that individualized treatment modalities and preventive vaccination should be further explored.     

居民膳食营养状况与食管癌和肝癌死亡率关系

目的了解食管癌与肝癌低发地区山东省淄博市桓台县、食管癌高发地区江苏省淮安市楚州区、肝癌高发地区广西壮族自治区扶绥县等3个地区居民的膳食营养状况,探讨膳食营养状况与食管癌、肝癌之间的关系。方法在3个地区各抽取1个自然村,选择年龄25~65岁,一般健康状况良好者作为调查对象,采用食物频率法,实地入户进行膳食调查。结果3个地区居民营养素的摄入有较大差异。江苏淮安楚州区调查对象的胡萝卜素、硫胺素、维生素E以及硒元素摄入量均低于山东桓台县,广西扶绥县调查对象的蛋白质、脂肪、视黄醇、硫胺素、钙、磷、硒以及膳食纤维摄入量均低于山东桓台县;山东地区调查对象的膳食营养状况明显好于其他2个地区。结论膳食营养因素可能与食管癌、肝癌的发生有一定关系。     

Management of colorectal cancer and diabetes

Colorectal cancer is associated with diabetes mellitus and both of these common conditions are often managed together by a surgeon. The surgical focus is usually upon cancer treatment rather than diabetes management. The relationship between colorectal cancer and diabetes is a complex one and can raise problems in both diagnosis and the management of patients with both conditions. This literature review explores the relationship between diabetes, diabetic treatment and colorectal cancer and addresses the issues that arise in diagnosing and treating this patient group. By highlighting these difficulties, this review aims to improve understanding and to provide clearer insight into both surgical and non-surgical management.     

Association between family history of cancer and breast cancer defined by estrogen and progesterone receptor status

There are recent data to suggest that risk factors for breast cancer may differ according to whether the tumor expresses detectable levels of the estrogen receptor (ER) and progesterone receptor (PR). While a family history of breast cancer is one of the most consistent predictors of the disease, we recently reported a modest inverse association with ER+PR− tumors. However, the definition of a family history of cancer did not consider second-degree relatives or cancer sites that may be etiologically related. The current report presents additional data analysis from the Iowa Women's Health Study, a prospective population-based cohort study conducted among 41,837 postmenopausal women. At baseline in 1986, respondents provided information on family history of cancers of the breast, ovaries, or uterus/endometrium in their mothers, sisters, daughters, maternal and paternal grandmothers, and maternal and paternal aunts. Data on family history of prostate cancer in fathers and brothers and age at onset of breast cancer in mothers and sisters were collected in 1992. Cohort members were followed for cancer incidence through the statewide tumor registry. After 7 years and more than 235,000 person-years of follow-up, 939 incident cases of breast cancer were identified. Information was obtained from the tumor registry on ER (+/−) and PR (+/−) status for 610 cases (65.0%). A family history of breast cancer in first-degree relatives was associated with increased risk (relative risk [RR] = 1.4; 95% confidence interval [CI]: 1.1–1.6) for all receptor-defined subtypes of breast cancer except ER+PR− tumors (RR = 0.7; 95% CI: 0.3–1.4). These results were unchanged when data on second-degree relatives were included. When the onset of breast cancer in relatives occurred at or before the age of 45 years, increased risks were evident only for ER−PR+ and ER−PR− tumors (RR = 2.3 and 3.3, respectively). Conversely, when relatives were affected with breast cancer after the age of 45 years, increased risks were most apparent for ER+PR+ and ER−PR+ tumors (RR = 1.3 and 3.2, respectively). A family history of prostate cancer in first-degree relatives was associated with a 1.2-fold increased risk of breast cancer (95% CI: 0.98–1.50), largely a reflection of the association with ER−PR− tumors (RR = 1.5; 95% CI: 0.8–3.0). The small numbers of cases in some categories and the corresponding wide CIs preclude definitive conclusions, but these data are at least suggestive that joint stratification of breast tumors on ER and PR status may be useful in partitioning breast cancer families into more homogeneous subsets. © 1996 Wiley-Liss, Inc.     

胃癌患者复发恐惧及其与抑郁的相关性研究

目的 探讨胃癌患者癌症复发恐惧及其与抑郁之间的关系,为进一步干预提供依据。方法 采用一般资料问卷、癌症患者恐惧疾病进展简化量表（FoP - Q - SF）、抑郁自评量表(SDS)对212例胃癌患者进行调查分析。结果 胃癌患者癌症复发恐惧总得分(35.43±10.44)分,抑郁程度得分为（57.05±9.52）分。FoP - Q - SF各维度与SDS各维度均呈正相关;多重线性回归分析显示患者年龄、病程、家庭人均收入、FoP - Q - SF是抑郁的影响因素,可解释总体变异度的58.5%,其中FoP - Q - SF独立影响抑郁水平总体变异的36.7%。结论 本研究中胃癌患者癌症复发恐惧处于中等水平,推测可通过降低复发恐惧水平来降低抑郁的发生。     

The hidden treasure-chests of the regional cancer registries

For physicians and patients, knowledge of the treatment results of individual hospitals is of great importance as it is known that hospitals with more experience perform better. Oncological characteristics of cancer patients in the Netherlands are collected by the nine Comprehensive Cancer Centres. The data are available from each affiliated hospital but remain anonymous. A plea is made for more transparency by requiring that the Comprehensive Cancer Centers place their data in the public domain.     

Conditions in utero and cancer risk

There is increasing recognition that conditions in utero are of importance for later cancer risk in several organs, particularly the testis and breast. A review of the most recent literature on this topic is therefore warranted. The PubMed database was searched for relevant recent literature on intrauterine conditions associated with cancer risk later in life, with particular emphasis on the testis, breast, but also studies pertaining to other organs were included. Epidemiological and experimental data support the hypothesis that factors acting in utero play a role in the development of cancer in the testis and breast. For other organs, such as the prostate, urinary system and colorectum, the results are inconclusive. While conditions during foetal life are associated with later cancer risk in the testis and breast, the biological mechanisms are for the most part elusive. They are, however, likely to involve hormonal disturbances, number of cells at risk, and genetic or epigenetic events.