Grupo de Epidemiologia de Cancro, Centro de Investigação do IPO Porto (CI-IPOP), Instituto Português de Oncologia do Porto (IPO Porto), Porto, Portugal
Ms. Jessica Rodrigues
Grupo de Epidemiologia de Cancro, Centro de Investigação do IPO Porto (CI-IPOP), Instituto Português de Oncologia do Porto (IPO Porto), Porto, Portugal
Background: Breast (BrC), colorectal (CRC) and lung (LC) cancers are the three most common and deadly cancers in women. Cancer screening entails an increase in early stage disease detection but is hampered by high false-positive rates and overdiagnosis/overtreatment. Aberrant DNA methylation occurs early in cancer and may be detected in circulating cell-free DNA (ccfDNA), constituting a valuable biomarker and enabling non-invasive testing for cancer detection. We aimed to develop a ccfDNA methylation-based test for simultaneous detection of BrC, CRC and LC. Methods: CcfDNA from BrC, CRC and LC patients and asymptomatic controls were extracted from plasma, sodium-bisulfite modified and whole-genome amplified. APC, FOXA1, MGMT, RARβ2, RASSF1A, SCGB3A1, SEPT9, SHOX2 and SOX17 promoter methylation levels were determined by multiplex quantitative methylation-specific PCR. Associations between methylation and standard clinicopathological parameters were assessed. Biomarkers’ diagnostic performance was also evaluated. Results: A “PanCancer” panel (APC, FOXA1, RASSF1A) detected the three major cancers with 72% sensitivity and 74% specificity, whereas a “CancerType” panel (SCGB3A1, SEPT9 and SOX17) indicated the most likely cancer topography, with over 80% specificity, although with limited sensitivity. Conclusions: CcfDNA’s methylation assessment allows for simultaneous screening of BrC, CRC and LC, complementing current modalities, perfecting cancer suspects’ triage, increasing compliance and cost-effectiveness.
Background: Lung cancer (LCa) is the most frequently diagnosed and lethal cancer worldwide. Histopathological subtyping, which has important therapeutic and prognostic implications, requires material collection through invasive procedures, which might be insufficient to enable definitive diagnosis. Aberrant DNA methylation is an early event in carcinogenesis, detectable in circulating cell-free DNA (ccfDNA). Herein, we aimed to assess methylation of selected genes in ccfDNA from LCa patients and determine its accuracy for tumor subtyping. Methods: Methylation levels of APC, HOXA9, RARβ2, and RASSF1A were assessed in three independent study groups (study group #1: 152 tissue samples; study group #2: 129 plasma samples; study group #3: 28 benign lesions of lung) using quantitative methylation-specific PCR. Associations between gene promoter methylation levels and LCa subtypes were evaluated using non-parametric tests. Receiver operating characteristic (ROC) curve analysis was performed. Results: In study group #2, HOXA9 and RASSF1A displayed higher methylation levels in small-cell lung cancer (SCLC) than in non-small-cell lung cancer (NSCLC). HOXA9 displayed high sensitivity (63.8%), whereas RASSF1A disclosed high specificity (96.2%) for SCLC detection in ccfDNA. Furthermore, HOXA9 methylation levels showed to be higher in squamous cell carcinoma in comparison with adenocarcinoma in study group #1. Conclusions: Methylation level assessments in ccfDNA may provide a minimally invasive procedure for LCa subtyping, complementing standard diagnostic procedures.
28 April 2021 in British Journal of Educational Psychology
The COVID‐19 pandemic led to potential delays in diagnosis and treatment of cancer patients, which may negatively affect the prognosis of these patients. Our study aimed to quantify the impact of COVID‐19 on the short‐term survival of cancer patients by comparing a period of 4 months after the outbreak began (2 March 2020) with an equal period from 2019. All cancer cases of the esophagus, stomach, colon and rectum, pancreas, lung, skin‐melanoma, breast, cervix, and prostate, from the Portuguese Oncology Institute of Porto (IPO‐Porto) and diagnosed between 2 March and 1 July of 2019 (before COVID‐19) and 2020 (after COVID‐19) were identified. Information regarding sociodemographic, clinical and treatment characteristics were collected from the cancer registry database and clinical files. Vital status was assessed to 31 October of the respective years. Cox proportional hazards regression was used to estimate crude and propensity score‐adjusted hazards ratio (HR) and 95% confidence intervals (95% CIs) of death. During follow‐up to 31 October, there were 154 (11.8%) deaths observed before COVID‐19 and 131 (17.2%) after COVID‐19, corresponding to crude and adjusted HRs (95% CI) of 1.51 (1.20‐1.91) and 1.10 (0.86‐1.40), respectively. Significantly higher adjusted hazards of death were observed for patients with Stage III cancer (HR = 2.37; 95% CI: 1.14‐4.94) and those undergoing surgical treatment (HR = 3.97; 95% CI: 1.14‐13.77) or receiving radiotherapy (HR = 1.96; 95% CI: 1.96‐3.74), while patients who did not receive any treatment had a lower mortality hazards (HR = 0.62; 95% CI: 0.46‐0.83). The higher overall short‐term mortality observed during the COVID‐19 pandemic largely reflects the effects of the epidemic on the case‐mix of patients being diagnosed with cancer.
Background: Global variations in survival for brain tumors are very wide when all histological types are considered together. Appraisal of international differences should be informed by the distribution of histology, but little is known beyond Europe and North America. Methods: The source for the analysis was the CONCORD database, a program of global surveillance of cancer survival trends, which includes the tumor records of individual patients from more than 300 population-based cancer registries. We considered all patients aged 0-99 years who were diagnosed with a primary brain tumor during 2000-2014, whether malignant or nonmalignant. We presented the histology distribution of these tumors, for patients diagnosed during 2000-2004, 2005-2009, and 2010-2014. Results: Records were submitted from 60 countries on 5 continents, 67 331 for children and 671 085 for adults. After exclusion of irrelevant morphology codes, the final study population comprised 60 783 children and 602 112 adults. Only 59 of 60 countries covered in CONCORD-3 were included because none of the Mexican records were eligible. We defined 12 histology groups for children, and 11 for adults. In children (0-14 years), the proportion of low-grade astrocytomas ranged between 6% and 50%. Medulloblastoma was the most common subtype in countries where low-grade astrocytoma was less commonly reported. In adults (15-99 years), the proportion of glioblastomas varied between 9% and 69%. International comparisons were made difficult by wide differences in the proportion of tumors with unspecified histology, which accounted for up to 52% of diagnoses in children and up to 65% in adults. Conclusions: To our knowledge, this is the first account of the global histology distribution of brain tumors, in children and adults. Our findings provide insights into the practices and the quality of cancer registration worldwide.