Journal of Cancer Epidemiology最新文献

Background: Two hypotheses attempt to explain the increase of thyroid cancer (TC) incidence: overdetection by excessive diagnostic scrutiny and a true increase in new cases brought about by environmental factors. Changes in the mechanism of detection and the risk of incidentally diagnosed TC could result in an increase of TC incidence.

Methods: Retrospective cohort study. We identified incident cases of TC from the pathological reports of patients in a HMO and review of clinical records. The results were analyzed in two periods: 2003-2007 and 2008-2012. Incidence rates expressed per 100,000 person-years (with 95% CI) and relative risk of incidence rates of incidental and nonincidental TC were estimated.

Results: The relative risk of incidentally detecting a thyroid cancer in 2008-2012 compared to 2003-2007 was 6.06 (95%CI 1.84-20.04). Clinical evaluations detected 31 (75.6%) cancers in the period 2003-2007 and 70 (51.8%) cancers in the period 2008-2012 (p<0.007). Although tumor median size was significantly lower in the period 2008-2012 (10 vs. 14 mm, p<0.03), tumors greater than 40 mm (4.3%) were only present in 2008-2012. The female/male ratio decreased between analyzed periods from 8 (3-21) to 4 (3-7).

Conclusions: Our findings partially support the hypothesis of increased incidence due to overdetection but do not explain the changes in the increase of larger tumors and decrease in the female/male ratio, which could be secondary to the influence of unidentified environmental factors.

Background: Laryngeal cancer is the second most common cancer in the head and neck. Since laryngeal cancer management is a complex process, there is still no standard strategy to treat this disease in order to increase the survival rate of the patients especially among those with advanced form of the disease.

Methods: A cohort study was undertaken to analyze factors predicting survival of the patients in advanced stage laryngeal cancer in the Southern Iran among all patients newly diagnosed with laryngeal cancer between 2000 and 2015.

Results: Data of a total number of 415 patients who have had been diagnosed with advanced laryngeal cancer during this period was used for analysis. The patients' 1-, 3-, 5-, and 10-year survival rates were 81%, 62%, 53%, and 38%, respectively. Multivariable Cox regression analyses indicated a significant relationship between patients' survival and age at diagnosis (P < 0.001), disease stage (P = 0.002), tumor grade (P = 0.008), positive L. node (P = 0.008), and type of treatment (P < 0.001). As expected, treatment strategy was identified as the most effective factor in survival of the patients. According to the results, patients who undergone surgical treatment experienced a longer survival than those who received other treatments.

Conclusion: This study showed that the survival of patients depends on several factors, among which, treatment strategy is the most important. Combination of total laryngectomy plus chemoradiation provides superior local control and better survival compared to either radiotherapy or chemoradiation in patients with advanced laryngeal cancer.

Objective: Medical chart abstraction is the gold standard for collecting breast cancer treatment data for monitoring and research. A less costly alternative is the use of administrative databases. This study will evaluate administrative data in comparison to medical charts for breast cancer treatment information.

Study design and setting: A retrospective cohort design identified 2,401 women in the Ontario Breast Screening Program diagnosed with invasive breast cancer from 2006 to 2009. Treatment data were obtained from the Activity Level Reporting and Canadian Institute of Health Information databases. Medical charts were abstracted at cancer centres. Sensitivity, specificity, positive and negative predictive value, and kappa were calculated for receipt and type of treatment, and agreement was assessed for dates. Logistic regression evaluated factors influencing agreement.

Results: Sensitivity and specificity for receipt of radiotherapy (92.0%, 99.3%), chemotherapy (77.7%, 99.2%), and surgery (95.8%, 100%) were high but decreased slightly for specific radiotherapy anatomic locations, chemotherapy protocols, and surgeries. Agreement increased by radiotherapy year (trend test, p < 0.0001). Stage II/III compared to stage I cancer decreased odds of agreement for chemotherapy (OR = 0.66, 95% CI: 0.48-0.91) and increased agreement for partial mastectomy (OR = 3.36, 95% CI: 2.27-4.99). Exact agreement in treatment dates varied from 83.0% to 96.5%.

Conclusion: Administrative data can be accurately utilized for future breast cancer treatment studies.

Inflammatory breast cancer (IBC) is a rare yet aggressive form of breast cancer. We examined differences in patient demographics and outcomes in IBC compared to locally advanced breast cancer (LABC) and all other breast cancer patients from the Breast and Prostate Cancer Data Quality and Patterns of Care Study (POC-BP), containing information from cancer registries in seven states. Out of 7,624 cases of invasive carcinoma, IBC and LABC accounted for 2.2% (N = 170) and 4.9% (N = 375), respectively. IBC patients were more likely to have a higher number (P = 0.03) and severity (P = 0.01) of comorbidities than other breast cancer patients. Among IBC patients, a higher percentage of patients with metastatic disease versus nonmetastatic disease were black, on Medicaid, and from areas of higher poverty and more urban areas. Black and Hispanic IBC patients had worse overall and breast cancer-specific survival than white patients; moreover, IBC patients with Medicaid, patients from urban areas, and patients from areas of higher poverty and lower education had worse outcomes. These data highlight the effects of disparities in race and socioeconomic status on the incidence of IBC as well as IBC outcomes. Further work is needed to reveal the causes behind these disparities and methods to improve IBC outcomes.

Objectives. The study objective was to determine how insurance status relates to treatment receipt and overall survival for patients with early-stage pancreatic exocrine carcinoma. Methods. SEER data were evaluated for 17,234 patients diagnosed with Stage I/II pancreatic exocrine carcinoma. Multivariate regression models controlled for personal characteristics to determine whether insurance status was independently associated with overall survival and receipt of radiation/surgery. Results. Odds of receiving radiation were 1.50 and 1.75 times higher for insured patients compared to Medicaid and uninsured patients, respectively (p < 0.01). Insured patients had 1.68 and 1.57 times increased odds of receiving surgery compared to Medicaid and uninsured patients (p < 0.01). Risk of death was 1.33 times greater (p < 0.01) in Medicaid patients compared to insured patients; when further adjusted for treatment, the risk of death was attenuated but remained significant (HR = 1.16, p < 0.01). Risk of death was 1.16 times higher for uninsured patients compared to insured patients (p = 0.02); when further adjusted for treatment, the risk of death was no longer significant (HR = 1.01, p = 0.83). Conclusions. Uninsured and Medicaid-insured patients experience lower treatment rates compared to patients who have other insurances. The increased likelihood of treatment appears to explain the insured group's survival advantage.

It is not yet clear whether white blood cell DNA global methylation is associated with breast cancer risk. In this review we examine the relationships between multiple breast cancer risk factors and three markers of global DNA methylation: LINE-1, 5-mdC, and Alu. A literature search was conducted using Pubmed up to April 1, 2016, using combinations of relevant outcomes such as "WBC methylation," "blood methylation," "blood LINE-1 methylation," and a comprehensive list of known and suspected breast cancer risk factors. Overall, the vast majority of reports in the literature have focused on LINE-1. There was reasonably consistent evidence across the studies examined that males have higher levels of LINE-1 methylation in WBC DNA than females. None of the other demographic, lifestyle, dietary, or health condition risk factors were consistently associated with LINE-1 DNA methylation across studies. With the possible exception of sex, there was also little evidence that the wide range of breast cancer risk factors we examined were associated with either of the other two global DNA methylation markers: 5-mdC and Alu. One possible implication of the observed lack of association between global WBC DNA methylation and known breast cancer risk factors is that the association between global WBC DNA methylation and breast cancer, if it exists, is due to a disease effect.

Background: Incorporation of molecular analysis of the epidermal growth factor receptor (EGFR) gene into routine clinical practice represents a milestone for personalized therapy of the non-small-cell lung cancer (NSCLC). However, the genetic testing of EGFR mutations has not yet become a routine clinical practice in developing countries. In view of different prevalence of such mutations among different ethnicities and geographic regions, as well as the limited existing data from Latin America, our aim was to study the frequency of major types of activating mutations of the EGFR gene in NSCLC patients from Uruguay.

Methods: We examined EGFR mutations in exons 18 through 21 in 289 NSCLC Uruguayan patients by PCR-direct sequencing.

Results: EGFR mutations were detected in 53 of the 289 (18.3%) patients, more frequently in women (23.4%) than in men (14.5%). The distribution by exon was similar to that generally reported in the literature.

Conclusions: This first epidemiological study of EGFR mutations in Uruguay reveals a wide spectrum of mutations and an overall prevalence of 18.3%. The background ethnic structure of the Uruguayan population could play an important role in explaining our findings.

Background: Hispanics diagnosed with cutaneous melanoma are more likely to present at advanced stages but the reasons for this are unknown. We identify census tracts at high risk for late stage melanoma diagnosis (LSMD) and examine the contextual predictors of LSMD in California, Texas, and Florida.

Methods: We conducted a cross-sectional study using geocoded state cancer registry data. Using hierarchical multilevel logistic regression models we estimated ORs and 95% confidence intervals for the impact of socioeconomic, Hispanic ethnic concentration, index of dissimilarity, and health resource availability measures on LSMD.

Results: We identified 12,493 cases. In California, late stage cases were significantly more likely to reside within census tracts composed mostly of Hispanics and immigrants. In Texas, LSMD was associated with residence in areas of socioeconomic deprivation and a higher proportion of immigrants. In Florida, living in areas of low education attainment, high levels of poverty, and a high percentage of Hispanic residents was significantly associated with LSMD. Residential segregation did not independently affect LSMD.

Conclusion: The influence of contextual predictors on LSMD varied in magnitude and strength by state, highlighting both the cosegregation of social adversity and poverty and the complexity of their interactions.