首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The number of involved lymph nodes exhibits considerable heterogeneity within populations. Here, the implications of population heterogeneity are explored with respect to the kinematics of nodal metastases. Data from the National Cancer Institute's Surveillance, Epidemiology, and End Results program for 224656 breast, 12404 gastric, 18015 rectal, 4117 cervical and 2443 laryngeal cancers as well as 9118 melanomas were used to construct frequency distributions for the number of involved nodes which were then fitted to the negative binomial distribution. The negative binomial distribution described the heterogeneity in nodal involvement well. The patterns of nodal involvement can be explained by either of two models: one where involved nodes could seed further nodal metastases, the other where the number of nodal metastases in any individual was randomly distributed, with the deviations between patients accounted for by population heterogeneity. Since the number of sampled nodes similarly approximated a negative binomial distribution, random involvement with superimposed population heterogeneity would more credibly explain both sets of observations.  相似文献   

2.
The objective was to examine changes in trace elements due to thyroid cancer in humans. Serum levels and tissue contents of trace elements (Zn, Cu, Mn, Mg, Fe and Se) were measured in 43 patients with thyroid cancer before and 4 days after surgery were compared to normal values. The serum levels of zinc in cancer patients were lower than those of normal subjects. Surgical removal of the cancer resulted in the restoration of these levels. Although serum Cu levels in patients were not different from normal, but post-operatively these levels rose significantly (p < 0.001). Levels of Fe, Mg and Mn were significantly lower (p < 0.001) post-operatively. There was no significant change in Serum Se levels. The thyroid tissue contents of these trace elements did not show a difference between the normal (Juxta-tumor) thyroid tissue and the cancerous lesion. Out of the six trace elements examined, the decrease of serum levels of zinc in cancer patients may be linked to the disease condition. It is suggested that this change: (a) may be used to demonstrate successful cancer surgery and (b) may have implications for a long-term follow-up of thyroid cancer patients.  相似文献   

3.
微生物与人体共生共存,主要分布在口腔、鼻腔、阴道、肠道、皮肤等部位,目前的研究已经表明微生物的分布特异性、种群的动态变化在人体恶性肿瘤的发生发展过程中发挥着重要的作用,为该领域今后的临床诊疗带来了全新的机遇和挑战。因此,笔者着重阐述微生物在口腔癌、胃癌、胆囊癌、胰腺癌、结直肠癌等常见恶性肿瘤中的作用及临床研究进展。旨在帮助临床医师了解目前微生物肿瘤学的发展现状及机遇与挑战。  相似文献   

4.
最近的一项研究报导,采用流式细胞仪分选技术从人胃癌细胞株中分离出CD44胃癌干细胞. 20~30×103个CD44+细胞入NOD/SCID 鼠腹部皮下和胃浆膜下能形成胃癌移植瘤, 100×103个CD44的细胞入NOD/SCID 鼠体内不形成肿瘤.采用无血清、无粘附间质的干细胞体外培养方法,发现CD44的细胞能形成肿瘤微球体,具有自我更新能力,而CD44的细胞则不形成球形克隆.上述的实验结果说明,在人胃癌细胞株中存在胃癌肿瘤干细胞.据此可以相信,胃癌干细胞是胃癌细胞中具有自我更新及分化潜能的一小群细胞,不能被目前的化疗、放疗等抗癌治疗措施所杀灭,是胃癌术后复发、肿瘤进展扩散转移的根源.胃癌干细胞可能来源于骨髓干细胞.随着对胃癌肿瘤干细胞生物学研究的深入,必将为胃癌的临床诊断和治疗提供新的策略.  相似文献   

5.
ObjectiveTo study the impact of the COVID-19 pandemic and consequent lockdown on the number of diagnoses of gynaecological malignancies in the Netherlands.MethodsWe performed a retrospective cohort study using data from the Netherlands Cancer Registry (NCR) on women of 18 years and older diagnosed with invasive endometrial, ovarian, cervical or vulvar cancer in the period 2017–2021. Analyses were stratified for age, socioeconomical status (SES) and region.ResultsThe incidence rate of gynaecological cancer was 67/100.000 (n = 4832) before (2017–2019) and 68/100.000 (n = 4833) during (2020) the COVID-19 pandemic. Comparing the number of diagnoses of the two periods for the four types of cancer separately showed no significant difference. During the first wave of COVID-19 (March-June 2020), a clear decrease in number of gynaecological cancer diagnoses was visible (20–34 %). Subsequently, large increases in number of diagnoses were visible (11–29 %). No significant differences in incidence were found between different age groups, SES and regions. In 2021 an increase of 5.9 % in number of diagnoses was seen.ConclusionIn the Netherlands, a clear drop in number of diagnoses was visible for all four types of gynaecological cancers during the first wave, with a subsequent increase in number of diagnoses in the second part of 2020 and in 2021. No differences between SES groups were found. This illustrates good organisation of and access to health care in the Netherlands.  相似文献   

6.
Estrogens along with progesterone/progestins, and other hormones, are important determinants of cancer in the breast, endometrium and ovary. Estrogens may increase the risk of breast cancer through various mechanisms and at various phases of life, with a possible synergistic effect of progesterone/progestins. Exposure to high doses of placental hormones, such as estrogens and/or progesterone, during pregnancy may play a pivotal role in reducing subsequent breast cancer susceptibility. Estrogens cause endometrial cancer, an effect that can be reduced, prevented or reversed by progesterone/progestin — if allowed to act for a sufficiently long period of each cycle. The role of sex hormones seems important for ovarian carcinogenesis. Intake of combined oral contraceptives has a substantial and well-documented protective effect on endometrial and ovarian cancer risks. Epidemiological observations and experimental data from an animal model indicate that estrogens may have an adverse effect, while progesterone/progestins have a risk reducing effect directly on the ovarian epithelium. Thus, estrogens and other sex hormones have potential effects on the three most important female cancers. Research has yet to define how some of the risk factors can be modified or treatment regimens can be improved to reduce these cancer risks.  相似文献   

7.
BackgroundTo assess the impact of comorbidity, measured by the Charlson Comorbidity Index (CCI), on survival in breast, colorectal and lung cancer.MethodsWe identified 3455 breast cancer, 3336 colorectal cancer and 2654 lung cancer patients through the Hospital del Mar cancer registry. The prevalence of comorbidities according to the CCI was calculated. Kaplan-Meier curves and the log-rank test were used to compare survival curves for each cancer location. Cox regression was used to calculate survival hazard ratios and 1-, 3- and 5-year mortality rate ratios adjusted by age, sex, CCI, place of first consultation, stage, treatment and period of diagnosis.ResultsThe overall unadjusted 5-year follow-up survival proportion was 82.6% for breast cancer, 55.7% for colorectal cancer, and 16.3% for lung cancer. Overall survival was associated with CCI  3 in breast cancer (HR: 2.33 95%CI: 1.76–3.08), colorectal cancer (HR: 1.39; 95%CI: 1.13–1.70) and lung cancer (HR: 1.22; 95%CI: 1.06–1.40). In breast cancer, the higher the CCI, the higher the adjusted mortality rate ratio and differences were greater in 5-year than in 1-year follow-up survival.ConclusionsComorbidity is a significant predictor of overall survival in cancer patients; however, it has a stronger impact on survival in breast cancer than in colorectal and lung cancer.  相似文献   

8.
BackgroundThe occurrence of colorectal cancer (CRC) in Estonia has been characterised by increasing incidence, low survival and no screening. The study aimed to examine long-term incidence and survival trends of CRC in Estonia with specific focus on subsite and stage.MethodsWe analysed CRC incidence and relative survival using Estonian Cancer Registry data on all cases of colorectal cancer (ICD-10 C18–21) diagnosed in 1995–2014. TNM classification was used to categorise stage.ResultsAge-standardized incidence of colon cancer increased both in men and women at a rate of approximately 1% per year. Significant increase was seen for right-sided tumours, but not for left-sided tumours. Rectal cancer incidence increased significantly only in men and anal cancer incidence only in women. Age-standardized five-year relative survival for colon cancer increased from 50% in 1995–1999 to 59% in 2010–2014; for rectal cancer, from 38% to 56%. Colon cancer survival improved significantly for left-sided tumours (from 51% to 62%) and stage IV disease (from 6% to 15%). For rectal cancer, significant survival gain was seen for stage II (from 58% to 75%), stage III (from 34% to 70%) and stage IV (from 1% to 12%).ConclusionIn the pre-screening era in Estonia, increase in colon cancer incidence was limited to right-sided tumours. Large stage-specific survival gain, particularly for rectal cancer, was probably due to better staging and advances in multimodality treatment. Nonetheless, more than one quarter of new CRC cases are diagnosed at stage IV, emphasising the need for an efficient screening program.  相似文献   

9.
BackgroundHead and neck squamous cell carcinomas (HNSCC) have not been fully examined in the Asian diasporas in the US, despite certain Asian countries having the highest incidence of specific HNSCCs.MethodsNational Cancer Database was used to compare 1046 Chinese, 887 South Asian (Indian/Pakistani), and 499 Filipino males to 156,927 Non-Hispanic White (NHW) males diagnosed with HNSCC between 2004−2013. Multinomial logistic regression was used to assess the association of race/ethnicity with two outcomes – site group and late-stage diagnosis. Temporal trends were explored for site groups and subsites.ResultsSouth Asians had a greater proportion of oral cavity cancer [OCC] compared to NHWs (59 % vs. 25 %; ORadj =7.3 (95 % CI: 5.9–9.0)). In contrast, Chinese (64 % vs. 9%; ORadj =34.0 (95 % CI: 26.5–43.6)) and Filipinos (47 % vs. 9%; ORadj =10.0 (95 % CI: 7.8–12.9)) had a greater proportion of non-oropharyngeal cancer compared to NHWs. All three Asian subgroups had a higher likelihood of being diagnosed by age 40 (14 % Chinese, 10 % South Asian and 8% Filipino compared to 3% in NHW; p < 0.001). Chinese males had lower odds of late-stage diagnosis, compared to NHWs. South Asian cases doubled from 2004 to 2013 largely due to an increase in OCC cases (34 cases in 2004 to 86 in 2013).ConclusionAsian diasporas are at a higher likelihood of specific HNSCCs. Risk factors, screening and survival need to be studied further, and policy changes are needed to promote screening and to discourage high-risk habits in these Asian subgroups.  相似文献   

10.
The pliability of cancer cells to mutate into several different phenotypes in an attempt to find one that will survive and colonize at the metastatic site is a tremendous "hurdle" to overcome in designing novel cancer therapeutics. New targets of therapy are essential if we are to effectively overcome the evasiveness of cancer. The interaction between the tumor cell and the surrounding microenvironment creates a vicious cycle that perpetuates disease survival and progression. The future of cancer therapy resides in the ability to focus on the recruited and exploited relationships of the cancer cell with the host environment. These therapies target cancer cell growth early and interrupt the vicious cycle that is created by the tumor cells interacting with bone components by inhibiting osteoclasts, osteoblasts, stromal cells, and endothelial cells. They alter the bone microenvironment, creating a hostile "soil" that prevents the "seed" from developing into bone metastases and represent a potential new platform for the development of prostate cancer therapeutics.  相似文献   

11.
17β-Hydroxysteroid dehydrogenases (17HSDs) catalyze the interconversions between active 17β-hydroxysteroids and less-active 17-ketosteroids thereby affecting the availability of biologically active estrogens and androgens in a variety of tissues. The enzymes have different enzymatic properties and characteristic cell-specific expression patterns, suggesting differential physiological functions for the enzymes. Epidemiological and endocrine evidence indicate that estrogens play a key role in the etiology of breast cancer while androgens are involved in mechanisms controlling the growth of prostatic cells, both normal and malignant. Recently, we have developed, using LNCaP prostate cancer cell lines, a cell model to study the progression of prostate cancer. In the model LNCaP cells are transformed in culture condition to more aggressive cells, able to grow in suspension cultures. Our results suggest that substantial changes in androgen and estrogen metabolism occur in the cells during the process. These changes lead to increased production of active estrogens during transformation of the cells. Data from studies of breast cell lines and tissues suggest that the oxidative 17HSD type 2 may predominate in human non-malignant breast epithelial cells, while the reductive 17HSD type 1 activity prevails in malignant cells. Deprivation of an estrogen response by using specific 17HSD type 1 inhibitors is a tempting approach to treat estrogen-dependent breast cancer. Our recent studies demonstrate that in addition to sex hormone target tissues, estrogens may be important in the development of cancer in some other tissues previously not considered as estrogen target tissues such as colon. Our data show that the abundant expression of 17HSD type 2 present in normal colonic mucosa is significantly decreased during colon cancer development.  相似文献   

12.
Cancer comprises a collection of diseases that occur in almost any tissue and it is characterized by an abnormal and uncontrolled cell growth that results in tumor formation and propagation to other tissues, causing tissue and organ malfunction and death. Despite the undeniable improvement in cancer diagnostics and therapy, there is an urgent need for new therapeutic and preventive strategies with improved efficacy and fewer side effects. In this context, purinergic signaling emerges as an interesting candidate as a cancer biomarker or therapeutic target. There is abundant evidence that tumor cells have significant changes in the expression of purinergic receptors, which comprise the G-protein coupled P2Y and AdoR families of receptors and the ligand-gated ion channel P2X receptors. Tumor cells also exhibit changes in the expression of nucleotidases and other enzymes involved in nucleotide metabolism, and the concentrations of extracellular nucleotides are significantly higher than those observed in normal cells. In this review, we will focus on the potential role of purinergic signaling in the ten most lethal cancers (lung, breast, colorectal, liver, stomach, prostate, cervical, esophagus, pancreas, and ovary), which together are responsible for more than 5 million annual deaths.  相似文献   

13.
The recent article by Liu et al. provided for highly interesting reading. Interestingly, recent data suggests that coumarin may exert significant anti-neoplastic effects in a number of systemic malignancies. Coumarin is also of clinical benefit in mammary malignancies. For instance, it attenuates the extent of extremity lymphedema following breast cancer surgery and radiation therapy. In one recent study, an almost 12.5 % decline in the volume of upper extremity lymphedema was noticed. As a result, quality of life is significantly improved. Similar attenuation of tumor growth has been seen in pulmonary malignancies. It mediates these anti-neoplastic effects by attenuating Bcl-2 expression within the tumor cells. On the other hand, Bax expression within the tumor cells is markedly accentuated. These changes have recently been confirmed in A549 cells.  相似文献   

14.
The diagnosis of secondary tumours represents one of the most important fields in the application of fine needle aspiration cytology (FNAC). We studied two patients, one with a history of breast cancer and one with a previous tumour of the thyroid, who showed a second mass, in the thyroid and in the breast, respectively, during follow up. The aim of our study was to evaluate if cytology, performed on FNAC smears, may distinguish a metastatic lesion from a second primary tumour, or if further immunocytochemistry should be performed. Our data demonstrate that, while cytology may be indicative of a second primary tumour, the histotype should be confirmed by immunocytochemical staining.  相似文献   

15.
《Biomarkers》2013,18(7):632-637
Abstract

Background: There was few study concentrated on the correlation between the evaluated tumor markers and lymph node metastasis. In this study, we aimed to evaluate the correlation between the CA724, CA242, CA199, CEA and the lymph node metastasis of gastric cancer and assess the prognostic value of them in different N stage patients.

Methods: We analyzed the correlation between serum level of CA724, CA242, CA199, CEA and lymph node metastasis in 1501 gastric cancer patients.

Results: Lymph node metastasis of gastric cancer was related with tumor location, Bormann type, tumor size, histological type, depth of invasion and TNM stage (p?<?0.05). The values of CA724, CA242, CA199 and CEA were positively correlated with the metastatic lymph node counts and the N stage (p?<?0.05). The later the N stage was, the levels of CA724, CA242 and CA199 were higher. The later the N stage was, the positive rates of tumor markers were higher (p?<?0.05). In comparing with single tumor markers, the positive rates of tumor markers combination were higher. The combination of CA724?+?CA242?+?CA199?+?CEA had highest positive rate. The higher CEA level related to N1 stage patients while higher CA199 was related with poor prognosis for N1 stage patients. For N0 and N2 stage patients, evaluation of CA724 indicated poorer prognosis. For N1 and N2 stage gastric patients, the patients with increased CA242 inclined to have shorter survival time.

Conclusions: The tumor makers CA724, CA242, CA199 and CEA were evaluated significantly in the gastric patients with later N stage. The combination of these four tumor markers maybe prefer diagnostic index of gastric cancer and its lymph node metastasis. These tumor markers can be a possible indicator of poorer prognosis in different N stage patients.  相似文献   

16.
BackgroundCancer is the leading cause of death in Canada and the estimated annual spending associated with cancer is approximately $7.5 billion. Projecting the future burden of cancer in Canada is essential for health planning and evaluation. We aimed to estimate the future incidence of cancer in Canada to 2042.MethodsAge-sex-region-specific cancer incidence data were obtained for the years 1983-2012 and cancer incidence was projected from 2013 to 2042 for the top five cancer sites. The modelling algorithm combined a mixture of cancer projection methods to select the best-fitted model. When the chosen model produced by the modelling algorithm resulted in estimates that were not consistent with expert opinion, an alternate model was selected that took into consideration historical changes in policy, screening and lifestyle behaviours. Incidence projections were made for Canada and its provinces.ResultsLung cancer incidence is estimated to rise to 14,866 cases in men and 19,162 in women in 2042. Colorectal cancer incidence is estimated to rise to 28,146 in men and 21,102 in women. Cases of bladder cancer are projected to rise to 10,708 and 3,364 in men and women, respectively. Breast cancer incidence is predicted to rise to 40,712 and prostate cancer incidence is projected to rise to 92,949.ConclusionThese cancer incidence projections up to 2042 can be used for planning cancer control strategies and prevention programs. Given the ongoing changes in the prevalence of risk factors and in cancer prevention policies, these estimates should be interpreted with caution.  相似文献   

17.
The cytogenetic endpoints in peripheral blood lymphocytes: chromosomal aberrations (CA), sister chromatid exchange (SCE) and micronuclei (MN) are established biomarkers of exposure for mutagens or carcinogens in the work environment. However, it is not clear whether these biomarkers also may serve as biomarkers for genotoxic effects which will result in an enhanced cancer risk. In order to assess this problem, Nordic and Italian cohorts were established, and preliminary results from these two studies indicated a predictive value of CA frequency for cancer risk, whereas no such associations were observed for SCE or MN. A collaborative study between the Nordic and Italian research groups, will enable a more thorough evaluation of the cancer predictivity of the cytogenetic endpoints. We here report on the establishment of a joint data base comprising 5271 subjects, examined 1965–1988 for at least one cytogenetic biomarker. Totally, 3540 subjects had been examined for CA, 2702 for SCE and 1496 for MN. These cohorts have been followed-up with respect to subsequent cancer mortality or cancer incidence, and the expected values have been calculated from rates derived from the general populations in each country. Stratified cohort analyses will be performed with respect to the levels of the cytogenetic biomarkers. The importance of potential effect modifiers such as gender, age at test, and time since test, will be evaluated using Poisson regression models. The remaining two potential effect modifiers, occupational exposures and smoking, will be assessed in a case-referent study within the study base.  相似文献   

18.
AimThe goal of this study was to determine whether a delay in starting treatment via surgery or neoadjuvant chemotherapy is related to a decrease in cancer-specific survival (CSS) in women with operable breast cancer (BrCr).BackgroundLimited medical infrastructure and a lack of cancer prevention awareness in low- and middle-income countries have caused high BrCr incidence and mortality rates.MethodsWe analyzed a retrospective cohort of 720 women treated at a single center from 2005 to 2012. CSS estimates were obtained by the Kaplan-Meier method. A Cox model of proportional risks was performed to obtain the risk of dying from BrCr. We also obtained the risk according to the category of treatment initiation.ResultsWomen with locally advanced stages and without hormone receptor expression were more likely to initiate treatment after 45 days. Patients in Stage IIIA had a 78.1% survival if treatment was initiated before 45 days (95% CI, 0.70–0.84) and 63.6% survival if treatment was started after 45 days (95% CI, 0.44–0.78; p < 0.001). Patients in Stage IIIB had a 62.9% survival if treatment was initiated before 45 days (95% CI, 0.53–0.72) and 57.4% survival if treatment started after 45 days (95% CI, 0.31-0.89; p < 0.001). Prognostic factors in which lower survival was recognized were Stage IIIA, Stage IIIB, treatment initiation after 45 days, and triple-negative tumors.ConclusionsThe initiation of treatment within the first 45 days of diagnosis of BrCr in women portends better survival compared with those who began treatment longer than 45 days from diagnosis.  相似文献   

19.
Backgroundsome recent studies have suggested that the risks of colon and rectal cancer increase with exposure to higher concentrations of nitrates in drinking water. This study is a meta-analysis of relevant studies.Methodsliterature published up to June 2021 was accessed and final results abstracted. Two cohort studies and seven case-control studies were analysed, and one case-control study not used because of limited data. Mixed effects meta-regression analysis was used to assess trends in colon cancer, rectal cancer, and colon cancer considered together, with nitrate concentrations in drinking water.ResultsThe usually accepted exposure upper limit for nitrates is 11.3 mg/l NO3-N. However most studies assess a lower range, with only one study providing data over 8 mg/l. Colorectal cancer risk increased by 2.4% (95% limits 0.4–4.5%) per unit increase in nitrate concentration, over a range from very low values to mid-range values. Extrapolation to higher dosages has insufficient data. The trend for rectal cancer is less than that for colon cancer.ConclusionThe increase in colorectal cancer risk with increasing nitrate concentration is lower than in some recent studies, and applies only over a small range. Extrapolation of these results to higher nitrate levels is not warranted. The studies vary greatly in their design, the nitrate concentrations assessed, and in their results. This association is weak and inconsistent, and may be influenced by bias and confounding factors. Any association of drinking water nitrates with colorectal cancer risk is small, and is uncertain.  相似文献   

20.
DNA copy number aberrations (CNAs) are a hallmark of cancer genomes. However, little is known about how such changes affect global gene expression. We develop a modeling framework, EPoC (Endogenous Perturbation analysis of Cancer), to (1) detect disease‐driving CNAs and their effect on target mRNA expression, and to (2) stratify cancer patients into long‐ and short‐term survivors. Our method constructs causal network models of gene expression by combining genome‐wide DNA‐ and RNA‐level data. Prognostic scores are obtained from a singular value decomposition of the networks. By applying EPoC to glioblastoma data from The Cancer Genome Atlas consortium, we demonstrate that the resulting network models contain known disease‐relevant hub genes, reveal interesting candidate hubs, and uncover predictors of patient survival. Targeted validations in four glioblastoma cell lines support selected predictions, and implicate the p53‐interacting protein Necdin in suppressing glioblastoma cell growth. We conclude that large‐scale network modeling of the effects of CNAs on gene expression may provide insights into the biology of human cancer. Free software in MATLAB and R is provided.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号