Marianna de Camargo Cancela

Oral cavity cancer in developed and in developing countries: population-based incidence.

The incidence of oral cavity cancer (OCC) is not well documented because it is rarely described in accord with the anatomic definition but is usually grouped with oropharyngeal subsites. We studied the incidence of OCC in developed and in developing countries.

Primary oral melanoma: Population-based incidence

Primary oral melanoma (POM) is a rare form of melanoma, generally diagnosed at a late stage and has poor prognosis. Epidemiological information has scarcely been reported in the literature over the past 40 years. Analyzing the Cancer Incidence in Five Continents volume IX (CI5-IX) database we found a total of 124,436 oral cavity cancers reported from all population-based cancer registries and 319 cases of POM reported by 67 cancer registries. To our knowledge this is the largest number of POM cases analyzed and accounts for 0.26% of all oral cavity cancers. ASR(W) for POM do not exceed 0.01 per 100,000 persons-year in all regions. The most common anatomic sites were palate (47%) and gum (27.6%) and a detailed oral mucosa examination and biopsies of nodular or macular lesions in these sites, especially on elderly patients, is advised to be routinely performed.

Leukemia mortality trends among children, adolescents, and young adults in Latin America

OBJECTIVE To describe and compare trends in leukemia mortality among children (0-14 years of age) and adolescents and young adults (AYA, 15-24 years of age) in 12 countries in Latin America during 1980-2004. METHODS Data from the World Health Organization mortality database was analyzed using a joinpoint regression model to identify significant mortality rate changes over time and to estimate annual percent change. RESULTS Leukemia is ranked first among cancer-related causes of death among children and AYA in Latin America. In children, the global percentage changes indicate increased rates for both sexes in Colombia, Ecuador, and Mexico, with substantially higher rates for Mexico. In AYA, significant increases were observed for both sexes in Mexico; Ecuador saw some increase for both sexes; and Colombia and Uruguay had increases in females only. Downward trends were observed in Argentina for both sexes, and in Costa Rica for males only. There were no major changes in the other countries analyzed. CONCLUSIONS Leukemia mortality rates among AYA are declining, but show less significant decreases than rates among children. The study results point to a global need for further advances, specifically for AYA, similar to those made by childhood leukemia therapeutic protocols. Also, specialized oncological centers exist in most countries of Latin America, but they are often inaccessible. Special attention should be given to Mexico due to the significant increase in mortality rates.

International incidence of oropharyngeal cancer: A population-based study

The incidence of oropharyngeal cancer is not well documented as it is rarely described according to the anatomic definition but usually grouped with oral cavity subsites. The aim of this study was to calculate oropharyngeal cancer incidence and compare it to oral cavity cancer incidence. Age-standardized incidence rates (ASR) of oropharyngeal cancer were calculated for the period between 1998 and 2002, based on data from Cancer Incidence in 5 Continents, Volume IX (CI5-IX). These ASRs were compared with previously published oral cavity cancer data. Among males, the highest ASRs were observed in France, Slovakia, Slovenia and Brazil. The highest oral cavity/oropharyngeal cancer rate ratio was observed in Pakistan, among males (6.2) and females (13.5). The results provide an overview of oropharyngeal cancer incidence and constitute a basis for the development of primary and secondary prevention, according to geographical variations and topography.

Trends in the incidence of oral cavity and oropharyngeal cancers in Spain

The purpose of this study was to analyze and compare incidence trends of oral cavity and oropharyngeal cancers, using data from population‐based Spanish cancer registries.

Abstracting stage in population-based cancer registries: The example of oral cavity and oropharynx cancers

Population-based cancer registries (PBCRs) are instruments to provide cancer incidence to promote cancer control and etiological research. A setting of mandatory (standard) variables is routinely collected for patient and tumor. One recommended variable is tumor stage, which supplies information on disease status and is an essential prognostic factor. However, it is not considered as necessary information to be collected by the PBCR. There are studies showing the value of stage as a prognostic variable to evaluate survival, socio-economic status, race and ethnics differences. Our aim is to analyze the feasibility of PBCRs in abstracting TNM for oral cavity and oropharynx. These topographies were selected due to the clinical accessibility of stage tumors by visual inspection and palpation. About 23% of the PBCRs who contributed to CI5-IX indicated their collection of TNM stage for all cancer sites. We analyzed 23,935 cases of oral cavity (OCC) and oropharynx cancer (OPC) from 13 PBCRs. Complete TNM stage for OCC was 52.7% for males and 47.6% for females; for OPC, it was 56% in both genders. Incomplete stage on OCC and OPC ranged from 22 to 25%. Missing was about 18-27% (most common in oral cavity). Missing stage was significantly higher in males for OCC aged > or =70 years, OR 1,64 (1.39-1.94). Our results demonstrate that OPC tend to have more stage, when compared with OCC. Even if it can be diagnosed by visual inspection, these results highlight the fact that information on stage can be a reliable indicator of access to healthcare and diagnosis awareness. Our results demonstrate that is feasible for PBCR to collect stage, although improving completeness of this information needs further technical training and international recommendation to adopt TNM stage as a standard variable for the PBCRs.

Cutaneous melanoma in Latin America: a population-based descriptive study

Cutaneous melanoma incidences vary between geographic regions and are a health concern for Caucasians and for all ethnic populations. In Latin America, data from population-based cancer registries of cutaneous melanoma incidence rates have rarely been reported. We searched the Cancer Incidence in Five Continents volume IX (CI5-IX) database for cutaneous melanoma and select cases by topography (C43) from 11 population-based cancer registries in Latin America. Between 1998 and 2002, a total of 4,465 cutaneous melanoma cases were reported in Latin America. The average age-standardized incidence rates (per 100,000 persons-year) was 4.6 (male) and 4.3 (female). This study presents an overview of cutaneous melanoma incidence in Latin America, highlighting the need to enhance coverage of population-based cancer registries in Latin America, to allow for a better understanding of this neoplasm in the region. Thus it can help in implementing primary prevention programs for the whole Latino population. At this point in time, early detection messages should target young women and older men in Latin America.

Mechanisms and mediation in survival analysis: towards an integrated analytical framework

BackgroundA wide-ranging debate has taken place in recent years on mediation analysis and causal modelling, raising profound theoretical, philosophical and methodological questions. The authors build on the results of these discussions to work towards an integrated approach to the analysis of research questions that situate survival outcomes in relation to complex causal pathways with multiple mediators. The background to this contribution is the increasingly urgent need for policy-relevant research on the nature of inequalities in health and healthcare.MethodsThe authors begin by summarising debates on causal inference, mediated effects and statistical models, showing that these three strands of research have powerful synergies. They review a range of approaches which seek to extend existing survival models to obtain valid estimates of mediation effects. They then argue for an alternative strategy, which involves integrating survival outcomes within Structural Equation Models via the discrete-time survival model. This approach can provide an integrated framework for studying mediation effects in relation to survival outcomes, an issue of great relevance in applied health research. The authors provide an example of how these techniques can be used to explore whether the social class position of patients has a significant indirect effect on the hazard of death from colon cancer.ResultsThe results suggest that the indirect effects of social class on survival are substantial and negative (-0.23 overall). In addition to the substantial direct effect of this variable (-0.60), its indirect effects account for more than one quarter of the total effect. The two main pathways for this indirect effect, via emergency admission (-0.12), on the one hand, and hospital caseload, on the other, (-0.10) are of similar size.ConclusionsThe discrete-time survival model provides an attractive way of integrating time-to-event data within the field of Structural Equation Modelling. The authors demonstrate the efficacy of this approach in identifying complex causal pathways that mediate the effects of a socio-economic baseline covariate on the hazard of death from colon cancer. The results show that this approach has the potential to shed light on a class of research questions which is of particular relevance in health research.

Prevalence of multimorbidity in the Brazilian adult population according to socioeconomic and demographic characteristics

Knowledge on the occurrence of multimorbidity is important from the viewpoint of public policies, as this condition increases the consumption of medicines as well as the utilization and expenses of health services, affecting life quality of the population. The objective of this study was to estimate prevalence of self-reported multimorbidity in Brazilian adults (≥18 years old) according to socioeconomic and demographic characteristics. A descriptive study is presented herein, based on data from the National Health Survey, which was a household-based survey carried out in Brazil in 2013. Data on 60,202 adult participants over the age of 18 were included. Prevalences and its respective confidence intervals (95%) were estimated according to sex, age, education level, marital status, self-reported skin color, area of residence, occupation and federative units (states). Poisson regression models univariate and multivariate were used to evaluate the association between socioeconomic and demographic variables with multimorbidity. To observe the combinations of chronic conditions the most common groups in pairs, trios, quartets and quintets of chronic diseases were observed. The prevalence of multimorbidity was 23.6% and was higher among women, in individuals over 60 years of age, people with low educational levels, people living with partner, in urban areas and among unemployed persons. The states of the South and Southeast regions presented higher prevalence. The most common groups of chronic diseases were metabolic and musculoskeletal diseases. The results demonstrated high prevalence of multimorbidity in Brazil. The study also revealed that a considerable share of the economically active population presented two or more chronic diseases. Data of this research indicated that socioeconomic and demographic aspects must be considered during the planning of health services and development of prevention and treatment strategies for chronic diseases, and consequently, multimorbidity.

Causes and outcomes of emergency presentation of rectal cancer

Emergency presentation of rectal cancer carries a relatively poor prognosis, but the roles and interactions of causative factors remain unclear. We describe an innovative statistical approach which distinguishes between direct and indirect effects of a number of contextual, patient and tumour factors on emergency presentation and outcome of rectal cancer. All patients diagnosed with rectal cancer in Ireland 2004–2008 were included. Registry information, linked to hospital discharge data, provided data on patient demographics, comorbidity and health insurance; population density and deprivation of area of residence; tumour type, site, grade and stage; treatment type and optimality; and emergency presentation and hospital caseload. Data were modelled using a structural equation model with a discrete‐time survival outcome, allowing us to estimate direct and mediated effects of the above factors on hazard, and their inter‐relationships. Two thousand seven hundred and fifty patients were included in the analysis. Around 12% had emergency presentations, which increased hazard by 80%. Affluence, private patient status and being married reduced hazard indirectly by reducing emergency presentation. Older patients had more emergency presentations, while married patients, private patients or those living in less deprived areas had fewer than expected. Patients presenting as an emergency were less likely to receive optimal treatment or to have this in a high caseload hospital. Apart from stage, emergency admission was the strongest determinant of poor survival. The factors contributing to emergency admission in this study are similar to those associated with diagnostic delay. The socio‐economic gradient found suggests that patient education and earlier access to endoscopic investigation for public patients could reduce emergency presentation.