Thomas C. Tucker

Global surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2)

BACKGROUND Worldwide data for cancer survival are scarce. We aimed to initiate worldwide surveillance of cancer survival by central analysis of population-based registry data, as a metric of the effectiveness of health systems, and to inform global policy on cancer control. METHODS Individual tumour records were submitted by 279 population-based cancer registries in 67 countries for 25·7 million adults (age 15-99 years) and 75,000 children (age 0-14 years) diagnosed with cancer during 1995-2009 and followed up to Dec 31, 2009, or later. We looked at cancers of the stomach, colon, rectum, liver, lung, breast (women), cervix, ovary, and prostate in adults, and adult and childhood leukaemia. Standardised quality control procedures were applied; errors were corrected by the registry concerned. We estimated 5-year net survival, adjusted for background mortality in every country or region by age (single year), sex, and calendar year, and by race or ethnic origin in some countries. Estimates were age-standardised with the International Cancer Survival Standard weights. FINDINGS 5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005-09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15-19% in North America, and as low as 7-9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10-20% between 1995-99 and 2005-09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995-99 and 2005-09 have generally been slight. For women diagnosed with ovarian cancer in 2005-09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005-09 was high (54-58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18-23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease. INTERPRETATION International comparison of survival trends reveals very wide differences that are likely to be attributable to differences in access to early diagnosis and optimum treatment. Continuous worldwide surveillance of cancer survival should become an indispensable source of information for cancer patients and researchers and a stimulus for politicians to improve health policy and health-care systems. FUNDING Canadian Partnership Against Cancer (Toronto, Canada), Cancer Focus Northern Ireland (Belfast, UK), Cancer Institute New South Wales (Sydney, Australia), Cancer Research UK (London, UK), Centers for Disease Control and Prevention (Atlanta, GA, USA), Swiss Re (London, UK), Swiss Cancer Research foundation (Bern, Switzerland), Swiss Cancer League (Bern, Switzerland), and University of Kentucky (Lexington, KY, USA).

Ten-year relative survival for epithelial ovarian cancer.

OBJECTIVE: Most patients with epithelial ovarian cancer who are alive at 5 years have active disease. Thus, 10-year survival rather than 5-year survival may be a more appropriate endpoint. Relative survival adjusts for the general survival of the United States population for that race, sex, age, and date at which the diagnosis was coded. Our objective was to estimate relative survival in epithelial ovarian cancer over the course of 10 years. METHODS: Using the Surveillance, Epidemiology and End Results 1995–2007 database, epithelial ovarian cancer cases were identified. Using the actuarial life table method, relative survival over the course of 10 years was calculated, stratified by stage, classification of residence, surgery as the first course of treatment, race, and age. RESULTS: There were 40,692 patients who met inclusion criteria. The overall relative survival was 65%, 44%, and 36% at 2, 5, and 10 years, respectively. The slope of decline in relative survival was reduced for years 5–10 as compared with years 1–5 after diagnosis. Relative survival at 5 years was 89%, 70%, 36%, and 17%, and at 10 years relative survival was 84%, 59%, 23%, and 8% for stages I, II III, and IV, respectively. At all stages, patients with nonsurgical primary treatment and those with advanced age had reduced relative survival. CONCLUSIONS: The 10-year relative survival for stage III is higher than expected. This information provides the physician and the patient with more accurate prognostic information. LEVEL OF EVIDENCE: III

Cancer in Appalachia, 2001–2003

Researchers have not been able to examine cancer incidence rates in Appalachia because high‐quality data have not been uniformly available across the region. This study is the first to report cancer incidence rates for a large proportion of the Appalachian population and describe the differences in incidence rates between Northern, Central, and Southern Appalachia.

Disparities in the application of adjuvant radiotherapy after breast-conserving surgery for early stage breast cancer: impact on overall survival.

Definitive local therapy of early stage breast cancer includes adjuvant radiotherapy after breast‐conserving surgery (BCS). The authors analyzed factors that influence the receipt of radiotherapy therapy and their resultant impact on outcome.

Arsenic and chromium in drinking water promote tumorigenesis in a mouse colitis-associated colorectal cancer model and the potential mechanism is ROS-mediated Wnt/β-catenin signaling pathway

Exposure to carcinogenic metals, such as trivalent arsenic [As(III)] and hexavalent chromium [Cr(VI)], through drinking water is a major global public health problem and is associated with various cancers. However, the mechanism of their carcinogenicity remains unclear. In this study, we used azoxymethane/dextran sodium sulfate (AOM/DSS)-induced mouse colitis-associated colorectal cancer model to investigate their tumorigenesis. Our results demonstrate that exposure to As(III) or Cr(VI), alone or in combination, together with AOM/DSS pretreatment has a promotion effect, increasing the colorectal tumor incidence, multiplicity, size, and grade, as well as cell inflammatory response. Two-dimensional differential gel electrophoresis coupled with mass spectrometry revealed that As(III) or Cr(VI) treatment alone significantly changed the density of proteins. The expression of β-catenin and phospho-GSK was increased by treatment of carcinogenic metals alone. Concomitantly, the expression of NADPH oxidase1 (NOX1) and the level of 8-OHdG were also increased by treatment of carcinogenic metals alone. Antioxidant enzymes, such as superoxide dismutase (SOD) and catalase, were decreased. Similarly, in an in vitro system, exposure of CRL-1807 to carcinogenic metals increased reactive oxygen species (ROS) generation, the expression of β-catenin, phospho-GSK, and NOX1. Inhibition of ROS generation by addition of SOD or catalase inhibited β-catenin expression and activity. Our study provides a new animal model to study the carcinogenicity of As(III) and Cr(VI) and suggests that As(III) and Cr(VI) promote colorectal cancer tumorigenesis, at least partly, through ROS-mediated Wnt/β-catenin signaling pathway.

Increasing Mastectomy Rates Among all Age Groups for Early Stage Breast Cancer: A 10‐Year Study of Surgical Choice

Abstract:  First‐line surgical options for early stage breast cancer and ductal carcinoma in situ include breast conserving surgery or mastectomy. We analyzed factors that influence the receipt of mastectomy and resultant trends over time. Registry analysis was carried out for 21,869 women who underwent up‐front surgical treatment for stage 0, I or II breast cancer between 1998 and 2007 using data from the Kentucky Cancer Registry. We examined the trend of treatment over time and assessed the probability of receiving mastectomy using multivariate logistic regression. Overall, 54.5% of women received breast conservation and 45.5% received mastectomy over a 10‐year period (annual BCS rate range: 46.9–61.2%). The overall mastectomy rate substantially decreased from 53.1% in 1998 to 38.8% in 2005 (p < 0.0001), but then increased to 45% in 2007 (p < 0.001). Between 2005 and 2007, the increase in mastectomies in the age groups of <50 years, 50–69 years, and ≥70 years was 7.5% (p = 0.0351), 4.9% (p = 0.0132) and, 8.0% (p = 0.0283), respectively. On multivariate analysis, the rate of receiving mastectomy was drastically higher for women with stage I or II (versus in situ) disease and moderate or poorly differentiated (versus well differentiated) histology. The rate was modestly higher for uninsured and government‐insured (versus privately insured) patients, patients older than 70 years (versus younger), rural (versus urban) location, receptor negative (versus receptor positive) disease, and unusual histologies (versus ductal and lobular histology). There was no statistically significant difference in surgical choice with regard to race. Determinants of mastectomy for in situ and early stage breast cancer include stage, histology, age, insurance status, county of residence, receptor status. The rate of mastectomy declined until 2005 and is now increasing across all age groups, especially for women < 50 years and ≥70 years.

Heterogeneity of Ovarian Cancer: Relationships Among Histological Group, Stage of Disease, Tumor Markers, Patient Characteristics, and Survival

Epidemiological studies have established associations between various reproductive factors and risk of ovarian cancer; it has also been observed that some of these risk factors are only associated with specific histological subgroups. To investigate the correlation of genetic alterations with these risk factors, we examined a consecutive series of 158 ovarian cancer cases treated at the University of Kentucky (1990–96). Common molecular genetic alterations (LOH on chromosome 17, P53 alterations, K-RAS mutations), histological and clinical characteristics of the disease, demographic patient information and survival were evaluated. These latter data were from the Kentucky Cancer Registry. Univariate analysis showed higher frequencies of chromosome 17 loss and P53 mutations in tumors of advanced stage and grade, and in older and post-menopausal women. Non-mucinous tumors were more likely to be classified as late stage, high-grade cancers, and to have chromosome 17 loss and P53 mutations. Survival analysis indicated that stage was the only independent significant variable. When stage was the outcome variable in multiple logistic regression analysis, histology and chromosome 17 loss were significantly associated with poor survival. This case-case study provides evidence that ovarian cancers of mucinous and non-mucinous histology are significantly different with respect to clinical characteristics, survival and molecular alterations. It also lends support to the hypothesis that ovarian cancer is a heterogeneous disease with distinct etiological factors and clinical outcomes, which may require different approaches to treatment.

Association of vitamin D receptor gene variants, adiposity and colon cancer

Vitamin D receptor (VDR) gene variants have been variably associated with risk of colon cancer in epidemiologic studies. We sought to further clarify the relationship between colon cancer and three single-nucleotide polymorphisms (SNPs) in the VDR gene (Cdx-2, FokI and TaqI) in a population-based case-control study of 250 incident cases and 246 controls. Colon cancer cases were more frequently homozygous for the Cdx-2 A allele (9.2 versus 4.1%, P = 0.06). Cdx-2 AA homozygotes were at increased risk with an unadjusted odds ratio (OR) of 2.47 [95% confidence interval (CI): 1.13-5.37, P = 0.022]; adjustment for age, sex, body mass index (BMI), non-steroidal anti-inflammatory use and family history of colorectal cancer yielded an OR of 2.27 (CI: 0.95-5.41, P = 0.065). Carriers of the FokI TT genotype were also at increased risk with an adjusted OR of 1.87 (CI: 1.03-3.38, P = 0.038). Haplotype analyses showed significant increased colon cancer risk for carriers of the Cdx-2-FokI A-T haplotype and the FokI-TaqI T-G haplotype. The three-SNP Cdx-2-FokI-TaqI (A-T-G) haplotype showed a similar association with an adjusted OR of 3.63 (CI: 1.01-13.07). A strong positive association was observed for the Cdx-2 variant among individuals with low BMI or low waist circumference. Our results suggest that genetic variation at the VDR locus, in particular Cdx-2 and FokI SNPs, may influence colon cancer risk and these associations may be modified by adiposity.

Reactive oxygen species mediate arsenic induced cell transformation and tumorigenesis through Wnt/β-catenin pathway in human colorectal adenocarcinoma DLD1 cells

Long term exposure to arsenic can increase incidence of human cancers, such as skin, lung, and colon rectum. The mechanism of arsenic induced carcinogenesis is still unclear. It is generally believed that reactive oxygen species (ROS) may play an important role in this process. In the present study, we investigate the possible linkage between ROS, β-catenin and arsenic induced transformation and tumorigenesis in human colorectal adenocarcinoma cell line, DLD1 cells. Our results show that arsenic was able to activate p47(phox) and p67(phox), two key proteins for activation of NADPH oxidase. Arsenic was also able to generate ROS in DLD1 cells. Arsenic increased β-catenin expression level and its promoter activity. ROS played a major role in arsenic-induced β-catenin activation. Treatment of DLD1 cells by arsenic enhanced both transformation and tumorigenesis of these cells. The tumor volumes of arsenic treated group were much larger than those without arsenic treatment. Addition of either superoxide dismutase (SOD) or catalase reduced arsenic induced cell transformation and tumor formation. The results indicate that ROS are involved in arsenic induced cell transformation and tumor formation possible through Wnt/β-catenin pathway in human colorectal adenocarcinoma cell line DLD1 cells.

A Common 8q24 Variant and the Risk of Colon Cancer: A Population-Based Case-Control Study

Three recent studies identified common variants on 8q24 that confer modestly increased susceptibility to colorectal cancer. Here, we replicate the association in a population-based case-control study of colon cancer, including 561 cases and 721 unrelated controls. The rs6983267 marker was significantly associated with colon cancer risk. Compared with those homozygous for the T allele, the heterozygous and homozygous carriers for the G allele had an age-adjusted odds ratio of 1.39 (95% confidence interval, 1.03-1.88) and 1.68 (95% confidence interval, 1.21-2.33), respectively. An additive model showed strong evidence for a gene-dose response relationship (Ptrend = 0.0022). The association remained statistically significant when restricted to Caucasians only (527 cases and 679 controls; Ptrend = 0.0056). Further adjustment for other known risk factors did not alter the results. Stratified analysis revealed no evidence for effect modification by family history of colorectal cancer, age, or gender. These data replicate the association identified from recent studies, providing additional evidence supporting the rs6983267 genetic polymorphism as a marker predisposing to colon cancer. (Cancer Epidemiol Biomarkers Prev 2008;17(2):339–42)