Risk of Colorectal Cancer in a Brazilian Population is Differentially Associated with the Intake of Processed Meat and Vitamin E.

The incidence and mortality rates of colorectal cancer (CRC) in Northeast Brazil are increasing. To study the association between CRC and diet, data were obtained from 64 patients with CRC and 123 sex- and age-matched controls. The dietary details were recorded using a validated food frequency questionnaire. Nutrient intake was calculated using Dietsys software (National Cancer Institute, Maryland, USA). In a binary logistic regression model of dietary components (model 1), the chance of CRC increased by 0.2% (odds ratio [OR] = 1.002; 95% confidence interval [CI]: 1.000-1.004) for each gram of processed meat intake per week (p < 0.010). Consumption of eggs decreased the chance by 0.1% per gram (OR = 0.999; 95% CI: 0.998-1.000; p < 0.050). The use of oil (including olive oil) for served food decreased the chance by 1.8% (OR = 0.982; 95% CI: 0.970-0.992) for each time consumed (p < 0.010). In a model of nutritional factors (model 2), intake of vitamin E decreased the chance by 16.8% (OR = 0.832; 95% CI: 0.725-0.940) for each milligram intake per week (p < 0.010). In model 1 and 2 smoking increased the chance of CRC by 10.294 (95%CI: 4.240-27.670) and 2.496 (95% CI: 1.425-3.566) times (p < 0.010; p < 0.010), respectively.

Haplotypes of single cancer driver genes and their local ancestry in a highly admixed long-lived population of Northeast Brazil.

Admixed populations have not been examined in detail in cancer genetic studies. Here, we inferred the local ancestry of cancer-associated single nucleotide polymorphisms (SNPs) and haplotypes of a highly admixed Brazilian population. SNP array was used to genotype 73 unrelated individuals aged 80-102 years. Local ancestry inference was performed by merging genotyped regions with phase three data from the 1000 Genomes Project Consortium using RFmix. The average ancestry tract length was 9.12-81.71 megabases. Strong linkage disequilibrium was detected in 48 haplotypes containing 35 SNPs in 10 cancer driver genes. All together, 19 risk and eight protective alleles were identified in 23 out of 48 haplotypes. Homozygous individuals were mainly of European ancestry, whereas heterozygotes had at least one Native American and one African ancestry tract. Native-American ancestry for homozygous individuals with risk alleles for HNF1B, CDH1, and BRCA1 was inferred for the first time. Results indicated that analysis of SNP polymorphism in the present admixed population has a high potential to identify new ancestry-associated alleles and haplotypes that modify cancer susceptibility differentially in distinct human populations. Future case-control studies with populations with a complex history of admixture could help elucidate ancestry-associated biological differences in cancer incidence and therapeutic outcomes.

Women's knowledge about risk factors of breast cancer in a Brazilian community.

Knowledge about risk factors for breast cancer was identified as an important variable that affects women's avoidance behavior and their screening performance. The present study assessed women's knowledge about risk factors and associated socio-economic variables. Data from 417 women aged 20-86 years were obtained in Caicó, Rio Grande do Norte, Brazil. In agreement with the recognition of 26 potential risk factors and prevention behaviors, two groups with good (N = 203) and poor (N = 214) knowledge were formed, respectively. Having a close relative with cancer remained the unique significant variable in the adjusted model. Women without any close relative with cancer, were 1.54 (95% confidence interval [CI] 1.036-2.288) times as likely to have poor knowledge, compared to women who had a close relative with cancer (p = 0.033). Other socio-economic variables, including income, employment status and educational level had no significant association with knowledge (p = 0.450, p = 0.914, p = 0.639, respectively). Of 417 women, 302 (72.42%), 339 (81.29%), and 309 (74.10%), respectively, did not identify "physical inactivity," "overweight after menopause," and "no breastfeeding of children" as risk factors. Knowledge could help to avoid risk factors and motivate prevention behavior. Information about risk factors should be disseminated in health campaigns.

Resolution and reconciliation of non-binary gene trees with transfers, duplications and losses.

Summary: Gene trees reconstructed from sequence alignments contain poorly supported branches when the phylogenetic signal in the sequences is insufficient to determine them all. When a species tree is available, the signal of gains and losses of genes can be used to correctly resolve the unsupported parts of the gene history. However finding a most parsimonious binary resolution of a non-binary tree obtained by contracting the unsupported branches is NP-hard if transfer events are considered as possible gene scale events, in addition to gene origination, duplication and loss. We propose an exact, parameterized algorithm to solve this problem in single-exponential time, where the parameter is the number of connected branches of the gene tree that show low support from the sequence alignment or, equivalently, the maximum number of children of any node of the gene tree once the low-support branches have been collapsed. This improves on the best known algorithm by an exponential factor. We propose a way to choose among optimal solutions based on the available information. We show the usability of this principle on several simulated and biological datasets. The results are comparable in quality to several other tested methods having similar goals, but our approach provides a lower running time and a guarantee that the produced solution is optimal. Availability and Implementation: Our algorithm has been integrated into the ecceTERA phylogeny package, available at http://mbb.univ-montp2.fr/MBB/download_sources/16__ecceTERA and which can be run online at http://mbb.univ-montp2.fr/MBB/subsection/softExec.php?soft=eccetera . Contact: celine.scornavacca@umontpellier.fr. Supplementary information: Supplementary data are available at Bioinformatics online.

On the fixed parameter tractability of agreement-based phylogenetic distances.

Three important and related measures for summarizing the dissimilarity in phylogenetic trees are the minimum number of hybridization events required to fit two phylogenetic trees onto a single phylogenetic network (the hybridization number), the (rooted) subtree prune and regraft distance (the rSPR distance) and the tree bisection and reconnection distance (the TBR distance) between two phylogenetic trees. The respective problems of computing these measures are known to be NP-hard, but also fixed-parameter tractable in their respective natural parameters. This means that, while they are hard to compute in general, for cases in which a parameter (here the hybridization number and rSPR/TBR distance, respectively) is small, the problem can be solved efficiently even for large input trees. Here, we present new analyses showing that the use of the "cluster reduction" rule-already defined for the hybridization number and the rSPR distance and introduced here for the TBR distance-can transform any [Formula: see text]-time algorithm for any of these problems into an [Formula: see text]-time one, where n is the number of leaves of the phylogenetic trees, p is the natural parameter and k is a much stronger (that is, smaller) parameter: the minimum level of a phylogenetic network displaying both trees.

Exact approaches for scaffolding.

This paper presents new structural and algorithmic results around the scaffolding problem, which occurs prominently in next generation sequencing. The problem can be formalized as an optimization problem on a special graph, the "scaffold graph". We prove that the problem is polynomial if this graph is a tree by providing a dynamic programming algorithm for this case. This algorithm serves as a basis to deduce an exact algorithm for general graphs using a tree decomposition of the input. We explore other structural parameters, proving a linear-size problem kernel with respect to the size of a feedback-edge set on a restricted version of Scaffolding. Finally, we examine some parameters of scaffold graphs, which are based on real-world genomes, revealing that the feedback edge set is significantly smaller than the input size.

Molecular breast cancer subtypes and therapies in a public hospital of northeastern Brazil.

BACKGROUND: The frequencies of molecular breast cancer subtypes vary among different human populations. The Northeastern region of Brazil has a mixed population of African, Indigenous and European ancestry. This retrospective study investigated breast cancer subtypes and applied therapies in a public hospital of Northeastern Brazil. METHODS: Data of 633 patients with invasive breast cancer from 2005 to 2011 were obtained from medical records. Status of hormone receptor (HR), HER2 and Ki67 expression index of 269 out of 633 patients were used to define subtypes of Luminal A and B, HER2 and triple negative (TN) breast cancer. Expression index of Ki67 ≥ 14% was applied to distinguish Luminal A from Luminal B subtypes. RESULTS: Overall, 185 (68.77%) and 132 (49.07%) patients showed positive hormone receptor (HR+) and positive HER2 (HER2+) tumors. The mean age ranged from 53.33 to 58.25 years for patients with tumors of Luminal B and Luminal A subtypes, respectively (p = 0.0182). In general, 67.39% of patients with TN tumors aged over 50 and 19.57% aged between 31 and 40 years (p = 0.0046). The rate of small tumors (T1: ≤ 2.0 cm) varied from 22.73% to 52.46% for TN and Luminal A subtypes (p = 0.0088). The rate of high graded (G3) tumors was increased for HER2 and TN subtypes (35.29% and 34.28%) compared to Luminal A and Luminal B subtypes (3.92% and 12.62%), respectively (p < 0.0001). The five-year survival rate ranged from 92.86% to 75.00%, for Luminal A, HER2 and TN subtypes, respectively (HR: 0.260 to 1.015; 95% CI: 0.043 to 3.594; p = 0.2589). Patients with HER2 positive (HER2+) breast tumors did not receive immunotherapy and chemotherapy application varied from 54.84% to 86.49% for Luminal A and HER2 subtypes, respectively (p = 0.0131). CONCLUSIONS: The results of this study revealed a high percentage of HER2+ breast tumors and an increased rate of patients with TN tumors aged over 50 years. This emphasizes the need for establishing immunotherapy as an additional therapeutic option to improve clinical outcomes for patients with HER2+ tumors and to investigate the risk factors of TN breast cancer.

A positive association between consanguinity and fertility in communities of Paraíba, Northeast Brazil.

BACKGROUND: Consanguinity of human populations can but does not have to be associated with increased fertility. A recent study involving communities of Northeast Brazil revealed increased levels of endogamy. SUBJECTS AND METHODS: Data from 20 451 interviewed couples and their 74 289 children were analysed. AIM: The present study aimed to compare fertility between consanguineous and unrelated couples of these communities. RESULTS: Consanguineous and unrelated couples of the 39 communities had an average of 4.3 (SD = 0.9) and 3.5 (SD = 0.8) children (p < 0.0001), respectively. Average offspring number of consanguineous couples varied from 3.9 (SD = 1.1) to 5.6 (SD = 3.4) for couples related at the level of third cousins and double first cousin/uncle-niece, respectively (p < 0.005). The correlation coefficient between Human Development Index and fertility was -0.38 (p = 0.0179) and -0.23 (p = 0.17) for unrelated and related couples, respectively. CONCLUSION: Results indicated an overall positive association between consanguinity and fertility. Fertility tended to be increased, for closely related couples, compared to those related more distantly.

Factors that Affect Performance of Clinical Breast Examination and Mammography Screening among Brazilian Women.

BACKGROUND: In the Brazilian health system, community health facilities consist of multidisciplinary teams that focus on family health, whereas health centers treat mainly illnesses of registered patients. In the present study we compared socio-economic factors and performance of mammography screening (MS) and clinical breast exam (CBE),  respectively, among women who used both types of public health service centers. METHODS: The present study included 180 women aged ≥40 years, who used different health service centers within the same municipal district. Of all 180 women, 110 (41.1%) and 70 (38.9%) used a health center and a community health facility. Logistic regression analysis was performed to calculate odds ratios (ORs) and confidence intervals (CIs) of variables. RESULTS: Regression modeling indicated that women who used the community health facility, performed annual MS 9.52 (OR= 0.105; 95%CI: 0.03- 0.36) times more often (p <0.001). In this model retirement and gynecological service use ≤ each second year, increased annual MS performance 8.16 (95%CI: 1.55- 54.32) and 7.78 (95%CI: 2.54- 23.79) times (p <0.001; p <0.001). Among 113 (62.8%) women who reported strong fear of MS, the chance of its performance was 35.71 (OR= 0.028; 95%CI: 0.02- 0.32) times decreased (p= 0.05). In a second model use of gynecological service ≤ each second year, increased chance of annual CBE performance 7.92 (95%CI: 3.25- 19.29) times (p <0.001). Women who used the community health facility performed annual and bi-annual CBE 2.90 (OR= 0.345; 95%CI: 0.14- 0.86) and 2.97 (OR= 0.337; 95%CI: 0.12- 0.92) times more often, compared to women who used the health center (p =0.030). CONCLUSIONS: Performance of MS and CBE varied both considerable among women who used different types of health service centers. Gynecological service use, fear and socioeconomic variables, additionally influenced regular performance of MS and CBE.

Consanguineous unions and the burden of disability: a population-based study in communities of Northeastern Brazil.

OBJECTIVES: The aim of this study was to identify communities at high risk of transmitting recessive genetic disorders by measuring levels of endogamy and offspring's rate of disabilities. METHODS: In a house-to-house population based-survey in the state of Paraíba, 20,462 couples were interviewed regarding kinship relation, number of siblings and offspring affected by mental or physical disabilities. RESULTS: The rate of consanguineous unions in the communities ranged from 6.0% to 41.14%, showing an average value of 20.19% ± 9.13%. The overall average inbreeding coefficient (F) was 0.00602 ± 0.00253, ranging from 0.00134 to 0.01182. Communities situated on the backlands had an increased average value of F compared to those closer to the seashore (P = 0.024). The average rate of disabled offspring varied from 2.96% ± 0.68% for unrelated unions to 10.44% ± 16.86% for related couples at the level of double first cousins or uncle-niece. The Spearman correlation coefficient between the overall rate of disabled offspring from all couples together and F was 0.510 (P < 0.01). CONCLUSION: Inbreeding increases the risk of disability which is unevenly distributed, varying considerably even in neighboring communities with similar Human Development Index and population density. Higher inbreeding communities are mostly located on the more economically underdeveloped backlands than on the coastal region. The identification of communities at high risk for genetic disorders could serve as basis for the establishment of Community Genetics programs.

Treewidth-based algorithms for the small parsimony problem on networks.

BACKGROUND: Phylogenetic reconstruction is one of the paramount challenges of contemporary bioinformatics. A subtask of existing tree reconstruction algorithms is modeled by the SMALL PARSIMONY problem: given a tree T and an assignment of character-states to its leaves, assign states to the internal nodes of T such as to minimize the parsimony score, that is, the number of edges of T connecting nodes with different states. While this problem is polynomial-time solvable on trees, the matter is more complicated if T contains reticulate events such as hybridizations or recombinations, i.e. when T is a network. Indeed, three different versions of the parsimony score on networks have been proposed and each of them is NP-hard to decide. Existing parameterized algorithms focus on combining the number c of possible character-states with the number of reticulate events (per biconnected component). RESULTS: We consider the parameter treewidth t of the underlying undirected graph of the input network, presenting dynamic programming algorithms for (slight generalizations of) all three versions of the parsimony problem on size-n networks running in times [Formula: see text], [Formula: see text], and [Formula: see text], respectively. Our algorithms use a formulation of the treewidth that may facilitate formalizing treewidth-based dynamic programming algorithms on phylogenetic networks for other problems. CONCLUSIONS: Our algorithms allow the computation of the three popular parsimony scores, modeling the evolutionary development of a (multistate) character on a given phylogenetic network of low treewidth. Our results subsume and improve previously known algorithm for all three variants. While our results rely on being given a "good" tree-decomposition of the input, encouraging theoretical results as well as practical implementations producing them are publicly available. We present a reformulation of tree decompositions in terms of "agreeing trees" on the same set of nodes. As this formulation may come more natural to researchers and engineers developing algorithms for phylogenetic networks, we hope to render exploiting the input network's treewidth as parameter more accessible to this audience.

On a greedy approach for genome scaffolding.

BACKGROUND: Scaffolding is a bioinformatics problem aimed at completing the contig assembly process by determining the relative position and orientation of these contigs. It can be seen as a paths and cycles cover problem of a particular graph called the "scaffold graph". RESULTS: We provide some NP-hardness and inapproximability results on this problem. We also adapt a greedy approximation algorithm on complete graphs so that it works on a special class aiming to be close to real instances. The described algorithm is the first polynomial-time approximation algorithm designed for this problem on non-complete graphs. CONCLUSION: Tests on a set of simulated instances show that our algorithm provides better results than the version on complete graphs.

Risk factors for breast cancer and their association with molecular subtypes in a population of Northeast Brazil.

BACKGROUND: The risk factors for breast cancer (BC) among women in Brazilian populations are poorly understood. To date, few Brazilian studies have addressed the potential association between risk factors and molecular BC subtypes. This case-control study aimed to identify risk factors for BC in a population of Northeast Brazil. METHODS: Data from 313 patients with invasive BC and 321 healthy controls were obtained from medical records from two cancer treatment centres and personal interviews. Of the 313 BC patients, 224 (71.6%) had reached menopause. The following distribution of subtypes was found among 301 patients: (1) Luminal A: 54 (17.9%); (2) Luminal B: 175 (58.1%); (3) HER2/neu: 29 (9.7%); and (4) triple-negative breast cancer (TNBC): 43 (14.3%). Odds ratios (ORs) and confidence intervals (CIs) were determined using regression analysis. RESULTS: Regression modelling indicated that family history, obesity (≥ 30.0 kg/m2), alcohol consumption and contraceptive use increased the overall risk of BC 1.78 (95% CI: 1.22-2.59), 1.69 (95% CI: 1.08-2.63), 2.21 (95% CI: 1.44-3.39) and 2.99 (95% CI: 2.09-4.28) times, respectively. After stratification for menopausal status, alcohol consumption increased the risk of BC 4.15 (95% CI: 2.13-8.11) times, and obesity, as a single variable, increased the risk of BC 2.02 (95% CI: 1.22-3.37) times, only among postmenopausal women. In a case-control analysis, the risk of TNBC and Luminal B breast cancer were 4.06 (95% CI: 1.58-10.42) and 1.87 times (95% CI: 1.13-3.11) higher, respectively, in obese women than in non-obese women. Furthermore, alcohol consumption increased the risk of Luminal A and B subtypes 7.08 (3.40-14.73) and 1.77 (1.07-2.92) times, respectively. CONCLUSION: Family history, contraceptive use, obesity and alcohol consumption increased the risk of BC. Obesity and alcohol consumption differentially increased risk of TNBC and Luminal molecular subtypes.

Shorter delay to treatment by integrated diagnostic services and NGO-provided support among breast cancer patients in two Brazilian referral centres.

BACKGROUND: The diagnosis of breast cancer requires a complicated series of diagnostic exams. The present study addressed the delay of patients who used publicly and privately financed diagnostic services. Non-governmental organizations (NGOs) donated diagnostic mammograms and biopsies. DESIGN AND METHODS: Data from 304 patients were obtained from two Brazilian referral centres. In one referral centre (FAP), diagnostic mammography, clinic-histopathological exam and immunohistochemistry were outsourced, whereas in the other centre (HNL), these services were integrated. Cox regression, Kaplan-Meier analysis and non-parametric tests were used to compare variables and time intervals. RESULTS: If diagnostic mammography was financed privately and covered by private health insurance, the likelihood of a delay of >90 days between the first medical visit and the initiation of treatment decreased 2.15-fold (95%CI: 1.06- 4.36; p=0.033) and 4.44-fold (95%CI: 1.58-12.46; p=0.004), respectively. If the clinic-histopathological exam was outsourced (FAP) and publicly or privately financed, the median time between diagnostic mammography and the diagnostic result was 53 and 65 days in the integrated (HNL) and outsourced public system, compared to 29 days in the outsourced private system (p<0.050). The median time between the first medical visit and the diagnostic results of patients who were supported by NGOs, who financed their diagnostic services privately, and who used exclusively public diagnostic services was, respectively, 28.0, 48.5 and 77.5 days (p<0.050). CONCLUSION: Patients who used privately financed health services had shorter delays. Compared to outsourcing, the integration of the publicly financed clinic- histopathological exam diminished the delay. The support of patients by NGOs accelerated patient flow.

Socioeconomic Factors and Health Status Disparities Associated with Difficulty in ADLs and IADLs among Long-Lived Populations in Brazil: A Cross-Sectional Study.

OBJECTIVE: To evaluate the association between socioeconomic factors, health status, and Functional Capacity (FC) in the oldest senior citizens in a metropolis and a poor rural region of Brazil. METHOD: Cross-sectional study of 417 seniors aged ≥80 years, data collected through Brazil's Health, Well-being and Aging survey. FC assessed by self-reporting of difficulties in Activities of Daily Living (ADLs) and Instrumental Activities of Daily Living (IADLs). Chi-square tests and multiple logistic regression analyses were performed using "R" statistical software. RESULTS: Socioeconomic and demographic inequalities in Brazil can influence FC in seniors aged 80 years and older. Comparatively, urban long-lived people had a higher prevalence of difficulties for ADLs and rural ones showed more difficulties for IADLs. Among urban oldest seniors, female gender and lower-income were correlated with difficulties for IADLs. Among rural oldest seniors, female gender, stroke, joint disease, and inadequate weight independently were correlated with difficulties for ADLs, while the number of chronic diseases was associated with difficulties for IADLs. CONCLUSION: Financial constraints may favor the development of functional limitations among older seniors in large urban centers. In poor rural areas, inadequate nutritional status and chronic diseases may increase their susceptibility to functional decline.

Breast Cancer Risk Perception and Mammography Screening Behavior of Women in Northeast Brazil.

Background: Previous studies suggest that education and income affect Brazilian women's breast cancer prevention behavior. The present study focused on the impact of perceived and estimated risk on mammography screening (MS) behavior. Materials and Methods: Information regarding socioeconomic variables and risk perception was obtained from 396 healthy women aged 40-79 years. Perceived comparative risk was measured on a seven-point Likert scale. A Breast Cancer Risk Assessment Tool of 5-year risk to develop breast cancer was used to determine objective risk. Estimated comparative risk was determined as categories of perceived risk relative to the objective risk. Regression analysis was applied to determine odds ratios (ORs) and confidence intervals (95% CIs) of variables. Results: Asked about the potential of MS to lower risk of death because of breast cancer, 215 (54.29%) responded that it does not lower risk. Women with low perceived comparative risk had a twofold (OR = 0.493; 95% CI: 0.24-1.00) decreased chance to participate in MS annually, compared with women with high-perceived comparative risk (p = 0.020). Women without family history had a 7.6-fold (OR = 0.132; 95% CI: 0.07-0.25) decreased chance of having a high-perceived comparative risk (p = 0.000). If compared with underestimation, the overestimation and accurate estimation of comparative risk tended to be associated with a decreased chance of MS attendance (p = 0.017). Regression modeling indicated that low educational level, no occupation, and no family history decreased the chance of women having MS (p = 0.040; p = 0.010; p = 0.022). Conclusions: Risk perception depended on family history. Present data did not indicate that overestimation, or accurate estimation of comparative risk, increased chance of MS attendance. Educational level, occupation status, and family history, instead, determined MS performance.

The structure of first-cousin marriages in Brazil.

This paper deals with the frequency and structure of first-cousin marriages, by far the most important and frequent type of consanguineous mating in human populations. Based on the analysis of large amounts of data from the world literature and from large Brazilian samples recently collected, we suggest some explanations for the asymmetry of sexes among the parental sibs of first-cousin marriages. We suggest also a simple manner to correct the method that uses population surnames to assess the different Wright fixation indexes FIS, FST and FIT taking into account not only alternative methods of surname transmission, but also the asymmetries that are almost always observed in the distribution of sexes among the parental sibs of first-cousins.

Availability of Diagnostic Services and their Impact on Patient Flow in Two Brazilian Referral Centres of Breast Cancer Treatment.

BACKGROUND: System delay (SD) is a leading cause of advanced stage of disease and poor prognosis among Brazilian breast cancer patients. METHODS: Cox regression and Kaplan-Meier analysis were used to identify variables that contributed to SD among 128 breast cancer patients. Time intervals between first medical consultation and treatment initiation were compared among patients of two referral centres: Patients of a referral centre with outsourced (FAP), respectively, integrated (HNL) diagnostic services. RESULTS: Women who used a specialized private clinic at the beginning of patient flow had an 2.32 fold increased chance (95% CI: 1.17 - 4.60; p = 0.016) of hospital admission within 90 days after first medical consultation, compared to women who used a public health care provider (HCP). Of 73 and 34 patients of the FAP hospital and the HNL, respectively, 10 (13.7%) and 11 (32.5%) used one HCP prior to hospital admission (p = 0.000). The median time between first medical consultation and treatment initiation was 150 days. The median time between first medical consultation and hospital admission was 136.0 and 52.0 days for patients of the FAP hospital, respectively the HNL (p < 0.050). The median time between first medical consultation and diagnostic mammography was 36.5 and 23.0 days for patients from the FAP hospital and the HNL (p < 0.050). CONCLUSIONS: Usage of public diagnostic services was associated with increased SD, whereas the usage of private diagnostic services diminished it. The usage of a lower number of HCPs accelerated patient flow.

Differential Impact of Education Level, Occupation and Marital Status on Performance of the Papanicolaou Test among Women from Various Regions in Brazil

Background: In Brazil, little is known regarding the underlying causes of differences among populations regarding socio-economic variables that affect women's cervical cancer screening behavior. The present study focused on socio-economic variables that affect women's performance of the Papanicolaou test, comparing two distinct Brazilian populations. Methods: We collected data regarding performance of the Papanicolaou test and socio-economic variables from 559 women in Mato Grosso do Sul (MS), in the Central East region, and 338 women in Paraíba (PB), in the Northeast region of Brazil. Nominal logistic regression modeling was performed to identify independent variables for both groups of data. Results: Of the women interviewed from MS and PB, 116 out of 599 (19.37%) and 94 out of 338 (27.81%), respectively, had not performed the Papanicolaou test within the last three years (p = 0.025). Low educational level characterized 570 (95.16%) and 203 (60.06%) of women from MS and PB, respectively (p = 0.000). Women in PB who had a low educational level and were unemployed had a 2.96-fold (OR = 0.338; 95% CI: 0.121 - 0.939) and 2.40-fold (OR = 0.416; 95% CI: 0.199 - 0.869) lower chance, respectively, to have performed the Papanicolaou test ≥ three times, or once within the last three years (p = 0.029; p = 0.014). The chance of women in MS who did not live in a stable relationship to have performed the test ≥ three times was 1.79-fold (OR = 0.560; 95% CI: 0.348 ­ 0.901) lower compared to women who reported a stable relationship (p = 0.039). Conclusions: High educational level, employment, and having a stable interpersonal relationship positively associated with performance of the Papanicolaou test among women in PB and MS. Despite having predominantly a low educational level, women in MS performed the Papanicolaou test more frequently than those in PB.