5,049 research outputs found
Unmodifiable variables related to thyroid cancer incidence
The incidence of thyroid cancer is significantly different between male and female patients. Thyroid cancer is also the only form of cancer where age can be considered a staging variable. Identifying biological prognostic factors such as age or sex is important as it helps select an optimal personalized therapy. The present analysis is an observational, prospective study that enrolled all patients with thyroid disease who were operated upon at a single center. The study aimed to determine the most frequent age at presentation, the predominance of one sex over the other, the incidence of malignant thyroid disease, and the relative risk for each sex to develop thyroid carcinoma. The incidence of thyroid carcinoma was higher for women than for men, with a higher relative risk in the female subgroup. Incidence was also highest in the 50-60-year-old group. Given that studies show better survival for women and for younger patients, even when presenting with advanced disease, compared with older, male patients, such prognostic indicators should be a factor in the treatment decision
DNA polymerase B deficiency is linked to aggressive breast cancer: a comprehensive analysis of gene copy number, mRNA and protein expression in multiple cohorts
Short arm of chromosome 8 is a hot spot for chromosomal breaks, losses and amplifications in breast cancer. Although such genetic changes may have phenotypic consequences, the identity of candidate gene(s) remains to be clearly defined. Pol β gene is localized to chromosome 8p12 - p11 and encodes a key DNA base excision repair protein. Pol β may be a tumour suppressor and involved in breast cancer pathogenesis. We conducted the first and the largest study to comprehensively evaluate pol β in breast cancer. We investigated pol β gene copy number changes in two cohorts (n=128 & n=1952), pol β mRNA expression in two cohorts (n=249 & n=1952) and pol β protein expression in two cohorts (n=1406 & n=252). Artificial neural network analysis for pol β interacting genes was performed in 249 tumours. For mechanistic insights, pol β gene copy number changes, mRNA and protein levels were investigated together in 1 28 tumours and validated in 1952 tumours. Low pol β mRNA expression as well as low pol β protein expression was associated high grade, lymph node positivity, pleomorphism, triple negative, basal - like phenotypes and poor survival (ps<0.001). In oestrogen receptor (ER) positive sub - group that received tamoxifen, low pol β protein remains associated with aggressive phenotype and poor survival (ps<0.001). Artificial neural network analysis revealed ER as a top pol β interacting gene. Mechanistically, there was strong positive correlation between pol β gene copy number changes and pol β mRNA expression (p<0.0000001) and between pol β mRNA and pol β protein expression (p<0.0000001). This is the first study to provide evidence that pol β deficiency is linked to aggressive breast cancer and may have prognostic and predictive significance in patients
Risk algorithm using serial biomarker measurements doubles the number of screen-detected cancers compared with a single-threshold rule in the United Kingdom collaborative trial of ovarian cancer screening
PURPOSE: Cancer screening strategies have commonly adopted single-biomarker thresholds to identify abnormality. We investigated the impact of serial biomarker change interpreted through a risk algorithm on cancer detection rates.
PATIENTS AND METHODS: In the United Kingdom Collaborative Trial of Ovarian Cancer Screening, 46,237 women, age 50 years or older underwent incidence screening by using the multimodal strategy (MMS) in which annual serum cancer antigen 125 (CA-125) was interpreted with the risk of ovarian cancer algorithm (ROCA). Women were triaged by the ROCA: normal risk, returned to annual screening; intermediate risk, repeat CA-125; and elevated risk, repeat CA-125 and transvaginal ultrasound. Women with persistently increased risk were clinically evaluated. All participants were followed through national cancer and/or death registries. Performance characteristics of a single-threshold rule and the ROCA were compared by using receiver operating characteristic curves.
RESULTS: After 296,911 women-years of annual incidence screening, 640 women underwent surgery. Of those, 133 had primary invasive epithelial ovarian or tubal cancers (iEOCs). In all, 22 interval iEOCs occurred within 1 year of screening, of which one was detected by ROCA but was managed conservatively after clinical assessment. The sensitivity and specificity of MMS for detection of iEOCs were 85.8% (95% CI, 79.3% to 90.9%) and 99.8% (95% CI, 99.8% to 99.8%), respectively, with 4.8 surgeries per iEOC. ROCA alone detected 87.1% (135 of 155) of the iEOCs. Using fixed CA-125 cutoffs at the last annual screen of more than 35, more than 30, and more than 22 U/mL would have identified 41.3% (64 of 155), 48.4% (75 of 155), and 66.5% (103 of 155), respectively. The area under the curve for ROCA (0.915) was significantly (P = .0027) higher than that for a single-threshold rule (0.869).
CONCLUSION: Screening by using ROCA doubled the number of screen-detected iEOCs compared with a fixed cutoff. In the context of cancer screening, reliance on predefined single-threshold rules may result in biomarkers of value being discarded
Oral cancer in the UK: to screen or not to screen.
Although oral squamous cell carcinoma accounts for only a small proportion of malignant neoplasms in the UK, oral cancer incidence and mortality rates have been rising in recent years. The natural history of oral cancer is not adequately understood at present and there is very little information about the epidemiology of precancerous lesions in the UK. There are also insufficient data to provide firm evidence that the percentage of cases arising de novo is greater in the UK and the Western world as compared to the Indian subcontinent. Screening for oral cancer by visual examination is simple, inexpensive and causes little discomfort; however, there is no evidence for the effectiveness of screening for oral cancer either in reducing mortality from the disease or in reducing the incidence of invasive disease by detection and treatment of precancerous lesions. There is currently insufficient evidence to recommend population screening for oral cancer in the UK. Measures aimed at primary prevention of the disease may be a more feasible method of disease control at present
Chromosomal radiosensitivity of human immunodeficiency virus positive/negative cervical cancer patients in South Africa
Cervical cancer is the second most common cancer amongst South African women and is the leading cause of cancer-associated mortality in this region. Several international studies on radiation-induced DNA damage in lymphocytes of cervical cancer patients have remained inconclusive. Despite the high incidence of cervical cancer in South Africa, and the extensive use of radiotherapy to treat it, the chromosomal radiosensitivity of South African cervical cancer patients has not been studied to date. Since a high number of these patients are human immunodeficiency virus (HIV)-positive, the effect of HIV infection on chromosomal radiosensitivity was also investigated. Blood samples from 35 cervical cancer patients (20 HIV-negative and 15 HIV-positive) and 20 healthy controls were exposed to X-rays at doses of 6 MV of 2 and 4 Gy in vitro. Chromosomal radiosensitivity was assessed using the micronucleus (MN) assay. MN scores were obtained using the Metafer 4 platform, an automated microscopic system. Three scoring methods of the MNScore module of Metafer were applied and compared. Cervical cancer patients had higher MN values than healthy controls, with HIV-positive patients having the highest MN values. Differences between groups were significant when using a scoring method that corrects for false positive and false negative MN. The present study suggested increased chromosomal radiosensitivity in HIV-positive South African cervical cancer patients
HER2 Status in Premalignant, Early, and Advanced Neoplastic Lesions of the Stomach
Objectives. HER2 expression in gastric cancer (GC) has received attention as
a potential target for therapy with Trastuzumab. We reviewed the current knowledge on HER2
status in premalignant gastric lesions and in early (EGC) and advanced (AGC) GC to discuss
the possible pathogenetic and prognostic roles of HER2 overexpression in GC. Results.
HER2 overexpression was documented in gastric low-grade (LG) and high-grade intraepithelial neoplasia
(HG-IEN), with higher frequency in gastric type dysplasia. HER2 overexpression was significantly
associated with disease recurrence and poor prognosis in EGC representing an independent risk
factor for lymph node metastases. HER2 overexpression was more frequent in AGC characterized
by high grade, advanced stage, and high Ki-67 labeling index. The discordance in HER2
status was evidenced between primitive GC and synchronous or metachronous
metastases. Conclusions. HER2 overexpression in premalignant gastric
lesions suggests its potential involvement in the early steps of gastric carcinogenesis.
The assessment of HER2 status in EGC may be helpful for the identification of patients
who are at low risk for developing nodal metastases. Finally, the possible discordance in
HER2 status between primary GC and its synchronous metastases support routine assessment
of HER2 both in the primary GC and in its metastatic lesions
Pathogenesis of ovarian cancer: current perspectives
Objective: To present a review of current knowledge of the pathogenesis of ovarian cancer and its clinical implications.Data Source: Extensive literature search was conducted to identify relevant studies.Study Selection: Studies in the English language about or related to pathogenesis of ovarian cancer were selected.Data Extraction: Applicable findings from selected studies were extracted as reported in the studies.Data Synthesis: Proposed theories of pathogenesis, and source population of ovarian tumour cells are discussed, and classification of ovarian cancer presented. Clinical implications of these new insights are also presented. Traditionally, epithelial ovarian tumours are thought to arise from the ovarian surface epithelium. Proposed factors that drive ovarian tumourigenesis include incessant-ovulation, gonadotropin stimulation, inflammation, and hormonal stimulation. There is evidence suggesting that ovarian tumour cells arise from extra-ovarian sites with secondary involvement of the ovary; the most prevalent and aggressive histological type (serous tumours) being of tubal origin. Ovarian cancer is now classified as type I and II or type I, II and III on the basis of shared mutations, histogenetic pathways, and behaviour.Conclusion: The pathogenesis of ovarian cancer has not been established. Adoption of extra-ovarian origin of tumour cells may have implications for prevention, screening, and treatment of ovarian cancer.Key Words: Ovarian cancer, pathogenesis, Müllerian, extra- Müllerian, extra-ovarian, incessant-ovulation, ovarian surface epithelium, hormonal
International cancer microbiome consortium consensus statement on the role of the human microbiome in carcinogenesis
Objective In this consensus statement, an international panel of experts deliver their opinions on key questions regarding the contribution of the human microbiome to carcinogenesis.Design International experts in oncology and/or microbiome research were approached by personal communication to form a panel. A structured, iterative, methodology based around a 1-day roundtable discussion was employed to derive expert consensus on key questions in microbiome-oncology research.Results Some 18 experts convened for the roundtable discussion and five key questions were identified regarding: (1) the relevance of dysbiosis/an altered gut microbiome to carcinogenesis; (2) potential mechanisms of microbiota-induced carcinogenesis; (3) conceptual frameworks describing how the human microbiome may drive carcinogenesis; (4) causation versus association; and (5) future directions for research in the field.The panel considered that, despite mechanistic and supporting evidence from animal and human studies, there is currently no direct evidence that the human commensal microbiome is a key determinant in the aetiopathogenesis of cancer. The panel cited the lack of large longitudinal, cohort studies as a principal deciding factor and agreed that this should be a future research priority. However, while acknowledging gaps in the evidence, expert opinion was that the microbiome, alongside environmental factors and an epigenetically/genetically vulnerable host, represents one apex of a tripartite, multidirectional interactome that drives carcinogenesis.Conclusion Data from longitudinal cohort studies are needed to confirm the role of the human microbiome as a key driver in the aetiopathogenesis of cancer
Electromagnetic fields and environmental health
Invisible electromagnetic fields (EMFs) permeate the modern living environment. They emanate from sources such as electric power lines, home appliances, medical devices, mobile phones and their base stations. Microwave power transmission, a near-future technology that could soon be in practical use, may become a major producer of EMFs. Therefore, electromagnetic environments, including static magnetic fields and low- and high-frequency EMFs, are likely to increase worldwide. In late May 2011, the International Agency for Research on Cancer (IARC), a subagency of the World Health Organization (WHO), met to evaluate the carcinogenicity of radiofrequency (RF) EMFs from mobile phones. This meeting1 provided a good opportunity for deliberation on the effects of EMFs on human health and to consider future approaches to this issue. The report conclusions, outlined in this paper, suggest there is limited evidence for the carcinogenic effect of RF-EMFs, resulting in RF-EMFs being classified as possibly carcinogenic, but that more studies are necessary to draw quantitative conclusions
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