Early diagnosis, not differential treatment, explains better survival in service screening

A 3D Radiomics-Based Artificial Neural Network Model for Benign Versus Malignant Vertebral Compression Fracture Classification in MRI

To train an artificial neural network model using 3D radiomic features to differentiate benign from malignant vertebral compression fractures (VCFs) on MRI. This retrospective study analyzed sagittal T1-weighted lumbar spine MRIs from 91 patients (average age of 64.24 ± 11.75 years) diagnosed with benign or malignant VCFs from 2010 to 2019, of them 47 (51.6%) had benign VCFs and 44 (48.4%) had malignant VCFs. The lumbar fractures were three-dimensionally segmented and had their radiomic features extracted and selected with the wrapper method. The training set consisted of 100 fractured vertebral bodies from 61 patients (average age of 63.2 ± 12.5 years), and the test set was comprised of 30 fractured vertebral bodies from 30 patients (average age of 66.4 ± 9.9 years). Classification was performed with the multilayer perceptron neural network with a back-propagation algorithm. To validate the model, the tenfold cross-validation technique and an independent test set (holdout) were used. The performance of the model was evaluated using the average with a 95% confidence interval for the ROC AUC, accuracy, sensitivity, and specificity (considering the threshold = 0.5). In the internal validation test, the best model reached a ROC AUC of 0.98, an accuracy of 95% (95/100), a sensitivity of 93.5% (43/46), and specificity of 96.3% (52/54). In the validation with independent test set, the model achieved a ROC AUC of 0.97, an accuracy of 93.3% (28/30), a sensitivity of 93.3% (14/15), and a specificity of 93.3% (14/15). The model proposed in this study using radiomic features could differentiate benign from malignant vertebral compression fractures with excellent performance and is promising as an aid to radiologists in the characterization of VCFs.

Aptamer-Based Probes for Cancer Diagnostics and Treatment

Aptamers are single-stranded DNA or RNA oligomers that have the ability to generate unique and diverse tertiary structures that bind to cognate molecules with high specificity. In recent years, aptamer researches have witnessed a huge surge, owing to its unique properties, such as high specificity and binding affinity, low immunogenicity and toxicity, and simplicity of synthesis with negligible batch-to-batch variation. Aptamers may bind to targets, such as various cancer biomarkers, making them applicable for a wide range of cancer diagnosis and treatment. In cancer diagnostic applications, aptamers are used as molecular probes instead of antibodies. They have the potential to detect various cancer-associated biomarkers. For cancer therapeutic purposes, aptamers can serve as therapeutic or delivery agents. The chemical stabilization and modification strategies for aptamers may expand their serum half-life and shelf life. However, aptamer-based probes for cancer diagnosis and therapy still face several challenges for successful clinical translation. A deeper understanding of nucleic acid chemistry, tissue distribution, and pharmacokinetics is required in the development of aptamer-based probes. This review summarizes their application in cancer diagnostics and treatments based on different localization of target biomarkers, as well as current challenges and future prospects.

Evaluating the effectiveness of population-based breast cancer service screening: an analysis of parsimonious patient survival information with the time-varying Cox model

BACKGROUND

This study is aimed at estimating the unbiased effectiveness of population-based breast cancer service screening based on case survival information alone rather than large-scale individual screening data pursuant to the intention-to-treat principle of a randomized-controlled trial.

METHODS

A novel time-dependent switched design with two modalities of cancer detection (screen-detected vs clinically detected) was proposed to evaluate the effectiveness of breast cancer screening. We used data on 767 patients from Kopparberg in the Swedish Two-County trial and on 78 587 patients in the Taiwan population-based service screening. We estimated the relative rate of the screen-detected vs the clinically detected with adjustment for both truncation and lead-time biases. The absolute effectiveness in terms of the number needed to screen (NNS) for averting one death from breast cancer was estimated.

RESULTS

The relative rate of effectiveness was estimated as 33%, which was consistent with the 37% reported from the original Swedish randomized-controlled trial. The corresponding estimate for the Taiwan screening programme was 42%, which was also very close to that estimated using individual screening history data (41%). Both relative estimates were further applied to yield 446 and 806 of NNS for averting one death from breast cancer for the corresponding two data sets.

CONCLUSION

The proposed time-dependent switched design and analysis with two modalities of case survival information provides a very efficient means for estimating the unbiased estimates of relative and absolute effectiveness of population-based breast cancer service screening dispensing with a large amount of individual screening history data.

Prediction and interpretation of cancer survival using graph convolution neural networks

The survival rate of cancer has increased significantly during the past two decades for breast, prostate, testicular, and colon cancer, while the brain and pancreatic cancers have a much lower median survival rate that has not improved much over the last forty years. This has imposed the challenge of finding gene markers for early cancer detection and treatment strategies. Different methods including regression-based Cox-PH, artificial neural networks, and recently deep learning algorithms have been proposed to predict the survival rate for cancers. We established in this work a novel graph convolution neural network (GCNN) approach called Surv_GCNN to predict the survival rate for 13 different cancer types using the TCGA dataset. For each cancer type, 6 Surv_GCNN models with graphs generated by correlation analysis, GeneMania database, and correlation + GeneMania were trained with and without clinical data to predict the risk score (RS). The performance of the 6 Surv_GCNN models was compared with two other existing models, Cox-PH and Cox-nnet. The results showed that Cox-PH has the worst performance among 8 tested models across the 13 cancer types while Surv_GCNN models with clinical data reported the best overall performance, outperforming other competing models in 7 out of 13 cancer types including BLCA, BRCA, COAD, LUSC, SARC, STAD, and UCEC. A novel network-based interpretation of Surv_GCNN was also proposed to identify potential gene markers for breast cancer. The signatures learned by the nodes in the hidden layer of Surv_GCNN were identified and were linked to potential gene markers by network modularization. The identified gene markers for breast cancer have been compared to a total of 213 gene markers from three widely cited lists for breast cancer survival analysis. About 57% of gene markers obtained by Surv_GCNN with correlation + GeneMania graph either overlap or directly interact with the 213 genes, confirming the effectiveness of the identified markers by Surv_GCNN.

Differences in breast cancer risk after benign breast disease by type of screening diagnosis

Introduction

We aimed to assess differences in breast cancer risk across benign breast disease diagnosed at prevalent or incident screens.

Materials and methods

We conducted a retrospective cohort study with data from 629,087 women participating in a long-standing population-based breast cancer screening program in Spain. Each benign breast disease was classified as non-proliferative, proliferative without atypia, or proliferative with atypia, and whether it was diagnosed in a prevalent or incident screen. We used partly conditional Cox hazard regression to estimate the adjusted hazard ratios of the risk of breast cancer.

Results

Compared with women without benign breast disease, the risk of breast cancer was significantly higher (p-value = 0.005) in women with benign breast disease diagnosed in an incident screen (aHR, 2.67; 95%CI: 2.24–3.19) than in those with benign breast disease diagnosed in a prevalent screen (aHR, 1.87; 95%CI: 1.57–2.24). The highest risk was found in women with a proliferative benign breast disease with atypia (aHR, 4.35; 95%CI: 2.09–9.08, and 3.35; 95%CI: 1.51–7.40 for those diagnosed at incident and prevalent screens, respectively), while the lowest was found in women with non-proliferative benign breast disease (aHR, 2.39; 95%CI: 1.95–2.93, and 1.63; 95%CI: 1.32–2.02 for those diagnosed at incident and prevalent screens, respectively).

Conclusion

Our study showed that the risk of breast cancer conferred by a benign breast disease differed according to type of screen (prevalent or incident). To our knowledge, this is the first study to analyse the impact of the screening type on benign breast disease prognosis.

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Breast cancer risk after a benign breast disease varied with the screening type.

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Incident benign breast disease had a higher breast cancer risk than prevalent.

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The risk remained increased regardless of benign breast disease subtype.

Evidence for reducing cancer-specific mortality due to screening for breast cancer in Europe: A systematic review

BACKGROUND

The aim of this study was to quantify the impact of organised mammography screening on breast cancer mortality across European regions. Therefore, a systematic review was performed including different types of studies from all European regions and stringently used clearly defined quality appraisal to summarise the best evidence.

METHODS

Six databases were searched including Embase, Medline and Web of Science from inception to March 2018. To identify all eligible studies which assessed the effect of organised screening on breast cancer mortality, two reviewers independently applied predefined inclusion and exclusion criteria. Original studies in English with a minimum follow-up of five years that were randomised controlled trials (RCTs) or observational studies were included. The Cochrane risk of bias instrument and the Newcastle-Ottawa Scale were used to assess the risk of bias.

RESULTS

Of the 5015 references initially retrieved, 60 were included in the final analysis. Those comprised 36 cohort studies, 17 case-control studies and 7 RCTs. None were from Eastern Europe. The quality of the included studies varied: Nineteen of these studies were of very good or good quality. Of those, the reduction in breast cancer mortality in attenders versus non-attenders ranged between 33% and 43% (Northern Europe), 43%-45% (Southern Europe) and 12%-58% (Western Europe). The estimates ranged between 4% and 31% in invited versus non-invited.

CONCLUSION

This systematic review provides evidence that organised screening reduces breast cancer mortality in all European regions where screening was implemented and monitored, while quantification is still lacking for Eastern Europe. The wide range of estimates indicates large differences in the evaluation designs between studies, rather than in the effectiveness of screening.

Differences in Stage and Treatment of Breast Cancer across Italy Point to Inequalities in access to and Availability of Proper Care

Aims and background

Population-based cancer registry studies of patterns of care can help elucidate reasons for differences in breast cancer survival across Italy documented by previous studies. The aims of the present study were to investigate across-country variation in stage at presentation and standard care for breast cancer cases diagnosed in Italy in the early 2000s.

Methods

Samples of adult (≥15 years) women with breast cancer diagnosed in 2003–2005 were randomly selected in 9 Italian cancer registries. Logistic regression models were used to estimate the odds of receiving breast-conserving surgery plus radiotherapy (BCS + RT) in each cancer registry, age group, and disease stage category compared with the entire sample (reference); the z test was used to evaluate differences in proportions of stage at diagnosis, employment of chemotherapy in node-positive (N+) disease, and use of endocrine treatment in estrogen-receptor positive (ER+) and negative (ER-) tumors across Italy.

Results

Stage at diagnosis was earlier in northern/central registries than in southern areas. Compared with the reference, the odds of receiving BCS + RT was significantly lower in Trapani, Sassari and Naples (southern Italy) after adjusting for age and stage at diagnosis. Among N+ patients, 73% received adjuvant chemotherapy (range, 51% [Biella, northern Italy] to 87% [Ragusa, southern Italy]). Eighty percent of ER+ cancers (range, 50% [Biella, northern Italy] to 97% [Ragusa, southern Italy]) and 18% of ER-cancers (range, 6% [Modena, northern Italy] to 28% [Umbria, central Italy]) were treated with hormonal therapy.

Conclusions

Disparities in stage distributions and conservative surgery in breast cancer persist across Italy. On a positive note, we found lower variations in the use of systemic treatment between Italian regions.

Highly sensitive antibody-aptamer sensor for vascular endothelial growth factor based on hybridization chain reaction and pH meter/indicator

Vascular endothelial growth factor (VEGF) is a crucial signaling protein for the tumor growth and metastasis, which is also acted as the biomarkers for various diseases. In this research, we fabricate an aptamer-antibody sensor for point-of-care test of VEGF. Firstly, target VEGF is captured by antibody immobilized on the microplate, and then binds with aptamer to form the sandwich structure. Next, with the assist of glucose oxidase (GOx)-functionalized ssDNAs, hybridization chain reaction occurs using the aptamer as the primer. Thus, GOx are greatly gathered on the microplate, which catalyzes the oxidization of glucose, leading to the pH change. As a result, the detect limit at a signal-to-noise was estimated to be 0.5pg/mL of target by pH meter, and 1.6pg/mL of VEGF was able to be distinguished by naked eyes. Meanwhile, this method has been used assay VEGF in the serum with the satisfactory results.

Relationship between the method of detection and prognostic factors for breast cancer in a community with a screening programme

Objectives

To analyse and compare the prognostic factors of breast cancer in the target population of our community-screening programme as a function of the method of detection and to analyse the differences in the prognostic factors as a function of the patient's age and the screening episode.

Setting

A Breast Cancer-Screening Programme (BCSP) in Northeast Spain.

Methods

Observational study of all primary malignant breast lesions diagnosed in a woman between 50 and 69 years of age between 18 October 1995 and 31 December 2002. The 16 centres that women from the target population might have attended were contacted.

Results

A total of 225 (37.2%) of the lesions included were diagnosed through the BCSP, 59 (9.7%) interval cancers were detected, and 321 (53.1%) were detected through other circuits. Node involvement was significantly lower in the lesions detected at screening (32%) in comparison to the interval cancers (41.8%) and those detected through other circuits (47.5%). A significantly larger percentage of the interval tumours (28.6%) and the lesions diagnosed outside the BCSP (22.1%) scored 5.4 on the Nottingham Prognostic Index (NPI) than those diagnosed within the programme (10.9%). The relation between the NPI and the detection method was only statistically significant in the 65-69-year-old age group. The NPI score of the tumours detected by the BCSP showed a statistically significant association with age.

Conclusion

This analysis has shown notable differences in some prognostic factors for breast cancer according to the method of detection. Association between age and the a priori prognosis of the malignant lesions arises.

Aptamer-initiated on-particle template-independent enzymatic polymerization (aptamer-OTEP) for electrochemical analysis of tumor biomarkers

Herein, an aptamer-initiated on-particle template-independent enzymatic polymerization (aptamer-OTEP) strategy for electrochemical aptasensor (E-aptasensor) is developed for analysis of cancer biomarker carcino-embryonic antigen (CEA). A pair of DNA aptamers is employed which can be specifically bond with CEA simultaneously. One of the aptamer is thiolated at 3'-terminal and immobilized onto the gold electrode as a capture probe, while the other one has a thiol group at its 5'-terminal and is modified onto the gold nanoparticles surface to form a nanoprobe. In the present of target, the two aptamers can "sandwich" the target, thus the nanoprobe is attached to the electrode. Then terminal deoxynucleotidyl transferase (TdT) is employed to catalyze the incorporation of biotin labeled dNTPs into the 3'-OH terminals of the DNA aptamer on the nanoprobe. The as-generated long DNA oligo tentacles allow specific binding of numerous avidin modified horseradish peroxidase (Av-HRP), resulting in tens of thousands of HRP catalyzed reduction of hydrogen peroxide and sharply increasing electrochemical signals. Taking advantage of the enzyme based nucleic acid amplification and nanoprobe, this strategy is demonstrated to possess the outstanding amplification efficiency.

Explaining the Better Prognosis of Screening-Exposed Breast Cancers: Influence of Tumor Characteristics and Treatment

BACKGROUND

In England, population mammographic screening has been offered to women for over 20 years. Overall decrease in breast cancer mortality rates and improvements in cancer awareness and organization of medical care over this period call for a more current evaluation of the mediators behind the better prognosis of screening-exposed breast cancers.

METHODS

A case-control study was conducted within the English National Breast Screening Program. Women who died from primary breast cancer in 2008 to 2009 were matched (by year of birth, screening invitation, and area) to controls that received a diagnosis of invasive breast cancer at the time of the case diagnosis but survived the case death. Data were analyzed by unconditional logistic regression with adjustment for matching factors.

RESULTS

The unadjusted OR for dying from breast cancer associated with ever having attended breast screening was 0.44 [95% confidence interval (CI), 0.33-0.58]. After adjustment for lead time, overdiagnosis, and self-selection, the OR increased to 0.69 (95% CI, 0.50-0.94). Adjusting for tumor size, lymph node status, stage, grade, histopathology, and laterality accounted for all the screening effect (OR, 1.00; 95% CI, 0.71-1.40). Further adjustment for treatment factors only had a minimal impact on the OR (OR, 1.02; 95% CI, 0.72-1.45).

CONCLUSIONS

Our results suggest that earlier diagnosis, as reflected by tumor characteristics, remains the major mediator of the improvement in breast cancer survival due to participation in mammographic screening.

IMPACT

Mammographic screening continues to prevent breast cancer-related deaths in the epoch of adjuvant systemic therapy.

A comparison of clinicopathological characteristics and long-term survival outcomes between symptomatic and screen-detected breast cancer in Japanese women

BACKGROUND

Several studies from other countries have reported that patients with screen-detected breast cancer have better survival than those with symptomatic breast cancer. However, no such comparison has been performed in Japan. Therefore, we aimed to compare the clinicopathological characteristics and survival rates between symptomatic and screen-detected breast cancer in Japanese women.

METHODS

From January 2000 to December 2004, 977 and 182 women with symptomatic or screen-detected breast cancer, respectively, underwent surgery at a single Japanese hospital. We retrospectively reviewed these patients' clinicopathological data. Likelihood of death was estimated using the Kaplan-Meier method and the log-rank test. Multivariate analysis including mode of detection, tumor size, lymph node status, hormone receptor status, and adjuvant therapy administration was performed using the Cox proportional hazards model.

RESULTS

Screen-detected breast cancer was associated with increased rate of breast-conserving surgery, non-invasive carcinoma, smaller tumor size, decreased lymph node involvement, increased hormone receptor positivity, and decreased adjuvant chemotherapy administration. Compared to women with symptomatic tumors, those with screen-detected tumors had improved overall and breast cancer-specific survival rates. Factors associated with survival in univariate analysis were screen detection, tumor size, lymph node status, progesterone receptor status, and adjuvant chemotherapy administration.

CONCLUSIONS

Breast cancer screening in Japanese women has led to increases in the rates of breast-conserving surgery, hormone receptor positivity, and survival rates along with reductions in axillary lymph node dissection and adjuvant chemotherapy administration.

The role of miR-200a in mammalian epithelial cell transformation

Cancer is a multistep disease that begins with malignant cell transformation and frequently culminates in metastasis. MicroRNAs (miRNAs) are small regulatory 21-25 nt RNA molecules and are frequently deregulated in cancer. miR-200a is a member of the miR-200 family, which are known inhibitors of the epithelial-to-mesenchymal transition. As such, the tumor-suppressive role of miR-200a in oncogenesis has been well documented; however, recent studies have found a proliferative role for this miRNA as well as a prometastatic role in the later steps of cancer progression. Little is known about the role of this miRNA in the early stages of cancer, namely, malignant cell transformation. Here, we show that miR-200a alone transforms an immortalized rat epithelial cell line, and miR-200a cooperates with Ras to enhance malignant transformation of an immortalized human epithelial cell line. Furthermore, miR-200a induces cell transformation and tumorigenesis in immunocompromised mice by cooperating with a Ras mutant that activates only the RalGEF effector pathway, but not Ras mutants activating PI3K or Raf effector pathways. This transformative ability is in accordance with miR-200a targeting Fog2 and p53 to activate Akt and directly repress p53 protein levels, respectively. These results demonstrate an oncogenic role for miR-200a and provide a specific cellular context where miR-200a acts as an oncomiR rather than a tumor suppressor by cooperating with an oncogene in malignant cell transformation.

Supplementary Breast Ultrasound Screening in Asian Women with Negative But Dense Mammograms—A Pilot Study

Introduction: Dense breasts are common in Asian women and they limit the sensitivity of mammography. This study evaluates the performance of supplementary breast ultrasound screening in Asian women with dense mammograms. Materials and Methods: The study was approved by the hospital’s Institutional Review Board. A prospective clinical trial was performed between September 2002 and November 2004. Asymptomatic Asian women with negative and dense mammograms were offered supplementary ultrasound screening for breast cancer. Ultrasound assessment was categorised as U1 to U4. U1 and U2 cases were recommended routine interval screening mammography. U3 cases were recommended follow-up ultrasound in 6 months and routine interval screening mammography and U4 cases were recommended biopsy. Results: One hundred and forty-one women with mean age of 45.1 years were enrolled into the study. Mean scan time was 13.0 minutes (± 5.6 minutes) for bilateral vs 11.0 minutes (± 1.4 minutes) for unilateral scans. There were 10 patients and 14 patients in the in the U3 and U4 categories, respectively. Two U4 category patients were diagnosed with malignancy—a-6 mm ductal carcinoma-in-situ and a 13-mm invasive ductal carcinoma. The breast cancer detection rate was 1.4%. Sensitivity and specificity were 100% (2/2) and 88.5% (92/104) respectively. The positive predictive value was 14.3% (2/14) and the negative predictive value was 100% (92/92). Conclusion: This pilot study reveals the usefulness of supplementary ultrasound screening in detecting early stage mammographically and clinically occult breast cancers in Asian women with dense breasts. A larger long-term study is, however, needed to assess its feasibility and impact on breast cancer prognosis. Key words: Asian, Breast, Dense, Screening, Ultrasound

Mammography screening and breast cancer mortality in Australia: an aggregate cohort study

BACKGROUND

Evidence that mammography screening reduces breast cancer mortality derives from trials, with observational studies broadly supporting trial findings. The purpose of this study was to evaluate the national mammographic screening programme, BreastScreen Australia, using aggregate screening and breast cancer mortality data.

METHODS

Breast cancer mortality from 1990 to 2004 in the whole Australian population was assessed in relation to screening exposure in the target of women aged 50-69 years. Population cohorts were defined by year of screening (and diagnosis), five-year age group at screening (and diagnosis), and local area of residence at screening (and diagnosis). Biennial screening data for BreastScreen Australia were related to cumulated mortality from breast cancer in an event analysis using Poisson regression, and in a time-to-event analysis using Cox proportional hazards regression. Results were adjusted for repeated measures and the potential effects of mammography outside BreastScreen Australia, regionality, and area socio-economic status.

RESULTS

From the adjusted Poisson regression model, a 22% (95% CI:12-31%) reduction in six-year cumulated mortality from breast cancer was predicted for screening participation of approximately 60%, compared with no screening; 21% (95% CI:11-30%) for the most recently reported screening participation of 56%; and 25% (95% CI:15-35%) for the programme target of 70% biennial screening participation. Corresponding estimates from the Cox proportional hazard regression model were 30% (95% CI:17-41%), 28% (95% CI:16-38%) and 34% (95% CI:20-46%).

CONCLUSIONS

Despite data limitations, the results of this nationwide study are consistent with the trial evidence, and with results of other service studies of mammography screening. With sufficient participation, mammography screening substantially reduces mortality from breast cancer.

Comparison between screen-detected and symptomatic breast cancers according to molecular subtypes

Breast cancer screening programs make it possible to detect early cancer, thus reducing breast cancer mortality. We studied the clinicopathologic characteristics and prognosis of screen-detected invasive breast cancer compared with symptomatic breast cancer. And we compared the result according to molecular subtypes (luminal A, luminal B, Her2, and triple negative), with the goal of identifying the role of screening in each subtypes. From January 2002 to June 2008, 3,141 patients who underwent surgery for the treatment of invasive ductal carcinoma at Samsung Medical Center were included. Among them, 1,025 patients were screen-detected, and 2,116 patients who were screened over 2 years or never were symptomatic. We retrospectively reviewed the clinical and pathologic data. Screen-detected breast cancer was associated with older age, smaller tumor size, more hormone-receptor positive, less lymph node involvement, earlier stage, and reduced mortality compared with symptomatic breast cancer (P < 0.001). According to the molecular subtype, luminal A was most common (63.6%) and showed the most obvious survival benefit in screen-detected tumors in comparison with symptomatic tumors (5-year OS: 99.7 vs. 96.5%, 5-year DFS: 96.4 vs. 90.7%). Screen detection was independently associated with improved overall and disease-free survival outcomes after adjustment for covariates (HR 0.32, P = 0.035; HR 0.58, P = 0.020, respectively) only in the luminal A subtype. Differences in pathological features such as tumor size, nodal status, grade, and age at diagnosis with different molecular subtype distributions may explain the survival advantage of patients with screen-detected breast cancer. Screening programs seem to have a different efficacy depending on the molecular subtype of the breast cancer, especially in the luminal A subtype, for which screen detection acts as an independent prognostic factor itself.

The role of mammography screening attendance and detection mode in predicting breast cancer survival-is there added prognostic value?

INTRODUCTION

The aim of this study was to examine whether screening exposure status, defined as detection mode (screening, interval or symptomatic) combined with breast cancer screening attendance prior to diagnosis, had any additional value over detection mode in predicting breast cancer survival. We also assessed the effect of hormone replacement therapy (HRT) on the association of detection mode with breast cancer survival.

METHODS

We analysed and compared the associations of both screening exposure status and detection mode with 5-year breast cancer survival on a cohort of 3013 breast cancer patients, aged 50-74 years in Sweden. We used Cox proportional hazards modelling with adjustments for tumour size, grade, estrogen receptor (ER) and progesterone receptor (PR) status and lymph node involvement. We repeated the analyses after stratification for HRT use.

RESULTS

Multivariate hazard ratios (HR) for cancers detected in patients at subsequent screens, interval cancers and symptomatic cancers in patients with and without previous screening attendance were 1.3 (95%CI 0.7-2.3), 1.8 (95%CI 1.0-3.2), 1.8 (95%CI 0.9-3.6) and 2.2 (95%CI 1.2-4.1) respectively, compared with cancers detected at the first screen. The regression model including screening exposure status had no additional prognostic value over the model including detection mode (P=0.63). HRT users showed a more favourable survival than non-users; this was not influenced by detection mode.

CONCLUSION

The number of routine screening examinations attended in the 5-year period prior to diagnosis had no additional prognostic value over detection mode in predicting breast cancer survival.

Socioeconomic status as determinant for participation in mammography screening: assessing the difference between using women's own versus their partner's

OBJECTIVES

Earlier research has shown that participation in mammography screening tends to vary across socioeconomic levels. We assessed the difference between using the woman's own socioeconomic status (SES) and using that of her household or partner as determinant of participation in mammography screening.

METHODS

Participation data from two mammography screening programs in Denmark were linked to a national SES classification system providing data for each citizen, their partner, and household. We calculated the odds ratio of non-participation across SES levels using the woman's own, the household's, and her partner's SES status, respectively.

RESULTS

When using the woman's own SES, the odds ratio of non-participation showed a clear U-shape across SES levels, in both programs. When using the partner's SES the difference in non-participation across SES levels was significantly smaller (p < 0.001).

CONCLUSIONS

To what extent SES was a determinant for screening participation strongly depended on whether using the woman's own SES or that of her partner. In a public health perspective it is important to take this into account when addressing the problem of non-attendance in screening.

Variation in 'standard care' for breast cancer across Europe: a EUROCARE-3 high resolution study

On a population-based sample of 13,500 European breast cancer patients mostly diagnosed in 1996-1998 and archived by 26 cancer registries, we used logistic regression to estimate odds of conservative surgery plus radiotherapy (BCS+RT) versus other surgery, in T1N0M0 cases by country, adjusted for age and tumour size. We also examined: BCS+RT in relation to total national expenditure on health (TNEH); chemotherapy use in N+ patients; tamoxifen use in oestrogen-positive patients; and whether 10 nodes were examined in lymphadenectomies. Stage, diagnostic examinations and treatments were obtained from clinical records. T1N0M0 cases were 33.0% of the total. 55.0% of T1N0M0 received BCS+RT, range 9.0% (Estonia) to 78.0% (France). Compared to France, odds of BCS+RT were lower in all other countries, even after adjusting for covariates. Women of 70-99 years had 67% lower odds of BCS+RT than women of 15-39 years. BCS+RT was 20% in low TNEH, 58% in medium TNEH, and 64% in high TNEH countries. Chemotherapy was given to 63.0% of N+ and 90.7% of premenopausal N+ (15-49 years), with marked variation by country, mainly in post-menopause (50-99 years). Hormonal therapy was given to 55.5% of oestrogen-positive cases, 44.6% at 15-49 years and 58.8% at 50-99 years; with marked variation across countries especially in premenopause. The variation in breast cancer care across Europe prior to the development of European guidelines was striking; older women received BCS+RT much less than younger women; and adherence to 'standard care' varied even among countries with medium/high TNEH, suggesting sub-optimal resource allocation.

EUROCARE-4. Survival of cancer patients diagnosed in 1995-1999. Results and commentary

EUROCARE-4 analysed about three million adult cancer cases from 82 cancer registries in 23 European countries, diagnosed in 1995-1999 and followed to December 2003. For each cancer site, the mean European area-weighted observed and relative survival at 1-, 3-, and 5-years by age and sex are presented. Country-specific 1- and 5-year relative survival is also shown, together with 5-year relative survival conditional to surviving 1-year. Within-country variation in survival is analysed for selected cancers. Survival for most solid cancers, whose prognosis depends largely on stage at diagnosis (breast, colorectum, stomach, skin melanoma), was highest in Finland, Sweden, Norway and Iceland, lower in the UK and Denmark, and lowest in the Czech Republic, Poland and Slovenia. France, Switzerland and Italy generally had high survival, slightly below that in the northern countries. There were between-region differences in the survival for haematologic malignancies, possibly due to differences in the availability of effective treatments. Survival of elderly patients was low probably due to advanced stage at diagnosis, comorbidities, difficult access or lack of availability of appropriate care. For all cancers, 5-year survival conditional to surviving 1-year was higher and varied less with region, than the overall relative survival.

Survival trends in European cancer patients diagnosed from 1988 to 1999

We analysed data from 49 cancer registries in 18 European countries over the period 1988-1999 to delineate time trends in cancer survival. Survival increased in Europe over the study period for all cancer sites that were considered. There were major survival increases in 5 year age-adjusted relative survival for prostate (from 58% to 79%), colon and rectum (from 48% to 54% men and women), and breast (from 74% to 83%). Improvements were also significant for stomach (from 22% to 24%), male larynx (from 62% to 64%), skin melanoma (from 78% to 83%), Hodgkin disease (from 77% to 83%), non-Hodgkin lymphoma (from 49% to 56%), leukaemias (from 37% to 42%), and for all cancers combined (from 34% to 39% in men, and from 52% to 59% in women). Survival did not change significantly for female larynx, lung, cervix or ovary. The largest increases in survival typically occurred in countries with the lowest survival, and contributed to the overall reduction of survival disparities across Europe over the study period. Differences in the extent of PSA testing and mammographic screening, and increasing use of colonoscopy and faecal blood testing together with improving cancer care are probably the major underlying reasons for the improvements in survival for cancers of prostate, breast, colon and rectum. The marked survival improvements in countries with poor survival may indicate that these countries have made efforts to adopt the new diagnostic procedures and the standardised therapeutic protocols in use in more affluent countries.

Cancer screenings, diagnostic technology evolution, and cancer control

Screening should allow for the anticipation of cancer diagnosis at an earlier stage, when curative treatment is possible. Screening for cervical, large bowel, and breast cancer were shown to be effective in reducing mortality. The wide acceptance of the screening concept led to the wide diffusion also of screening of uncertain benefit against prostate cancer and skin melanoma. Diagnostic technologies are continuously evolving, and new tests are proposed to improve existing screenings or as screening tests for additional cancer sites (e.g., lung cancer). Cancer screening, however, is a complex and costly intervention that does not result only in benefits but also may cause harm. A major emerging problem of screening is overdiagnosis, or the detection of cases that would have not progressed to the symptomatic phase in the absence of screening. Thus, both experimental and observational evaluation studies are needed to reduce harm caused by screenings and to select effective interventions among many proposed innovations. Finally, the research of markers to assess the aggressive nature of screen-detected lesions is of great importance to improve screenings ' harm/benefit ratio.

Effectiveness of service screening: a case-control study to assess breast cancer mortality reduction

The aim of this study was the evaluation of the impact of service screening programmes on breast cancer mortality in five regions of Italy. We conducted a matched case-control study with four controls for each case. Cases were defined as breast cancer deaths occurred not later than 31 December 2002. Controls were sampled from the local municipality list and matched by date of birth. Screening histories were assessed by the local, computerised, screening database and subjects were classified as either invited or not-yet-invited and as either screened or unscreened. There were a total of 1750 breast cancer deaths within the 50 to 74-year-old breast cancer cases and a total of 7000 controls. The logistic conditional estimate of the cumulative odds ratios comparing invited with not-yet-invited women was 0.75 (95% CI: 0.62-0.92). Restricting the analyses to invited women, the odds ratio of screened to never-respondent women corrected for self-selection bias was 0.55 (95% CI: 0.36-0.85). The introduction of breast cancer screening programmes in Italy is associated with a reduction in breast cancer mortality attributable to the additional impact of service screening over and above the background access to mammography.

Breast cancer screening: evidence for false reassurance?

Tumour stage distribution at repeated mammography screening is, unexpectedly, often not more favourable than stage distribution at first screenings. False reassurance, i.e., delayed symptom presentation due to having participated in earlier screening rounds, might be associated with this, and unfavourably affect prognosis. To assess the role of false reassurance in mammography screening, a consecutive group of 155 breast cancer patients visiting a breast clinic in Rotterdam (The Netherlands) completed a questionnaire on screening history and self-observed breast abnormalities. The length of time between the initial discovery of breast abnormalities and first consultation of a general practitioner ("symptom-GP period") was compared between patients with ("screening group") and without a previous screening history ("control group"), using Kaplan-Meier survival curves and log-rank testing. Of the 155 patients, 84 (54%) had participated in the Dutch screening programme at least once before tumour detection; 32 (38%) of whom had noticed symptoms. They did not significantly differ from control patients (n = 42) in symptom-GP period (symptom-GP period > or = 30 days: 31.2% in the symptomatic screened group, 31.0% in the control group; p = 0.9). Only 2 out of 53 patients (3.8%) with screen-detected cancer had noticed symptoms prior to screening, reporting symptom-GP periods of 2.5 and 4 years. The median period between the first GP- and breast clinic visit was 7.0 days (95% C.I. 5.9-8.1) in symptomatic screened patients and 6.0 days (95% C.I. 4.0-8.0) in control patients. Our results show that false reassurance played, at most, only a minor role in breast cancer screening.

Evaluation of service mammography screening impact in Italy. The contribution of hazard analysis

12,987 invasive breast cancer cases were diagnosed in women aged 50-69 upto the year 2001 in nine Italian areas where a screening programme was active. Cases were followed up in 2005 for a total of 1921 breast cancer failures. The 10-year survival rates were 85.3% for the invited group against 75.6% for the non-invited. A time dependent analysis was performed using 5-year intervals. Crude hazard ratios for the invited group in comparison to the not invited group were 0.52 and 0.64 respectively in the (0-5) year and [5-10] year time windows. Hazard ratio adjusted for tumour characteristics was 0.96 in the [5-10] year time window, suggesting minimal or any length bias. Consistent with the results of randomised trials, these analyses of service screening data document a mortality reduction of 36% at 5-10 years after diagnosis.

Socio-demographic determinants of participation in mammography screening

Our objective was to use individual data on socio-demographic characteristics to identify predictors of participation in mammography screening and control to what extent they can explain the regional difference. We used data from mammography screening programmes in Copenhagen, 1991-1999, and Funen, 1993-2001, Denmark. Target groups were identified from the Population Register, screening data came from the health authority, and socio-demographic data from Statistics Denmark. Included were women eligible for at least 3 screens. The crude RR of never use versus always use was 3.21 (95%CI, 3.07-3.35) for Copenhagen versus Funen, and the adjusted RR was 2.55 (95%CI, 2.43-2.67). The adjusted RR for never use among women without contact to a primary care physician was 2.50 (95% CI, 2.31-2.71) and 2.89 (95% CI, 2.66-3.14), and for women without dental care 2.94 (95% CI, 2.77-3.12) and 2.88 (95% CI, 2.68-3.10) for Copenhagen and Funen, respectively. Other important predictive factors for nonparticipation were not being married and not being Danish. In conclusion, to enhance participation in mammography screening programmes special attention needs to be given to women not using other primary health care services. All women in Copenhagen, irrespective of their socio-demographic characteristics, had low participation. Screening programmes have to find ways to handle this urbanity factor.

A comparison of trends in incidence and mortality rates of breast cancer, incidence to mortality ratio and stage at diagnosis between Arab and Jewish women in Israel, 1979–2002

In Israel, breast cancer is the most common malignancy in women, but there are large intra-population differences. The aim of this study was to compare the incidence and mortality, incidence to mortality rate ratio and stage at diagnosis of breast cancer between Arab and Jewish women in Israel. Data on all cases of breast cancer, stage at diagnosis and mortality were obtained from the National Cancer Registry and the Central Bureau of Statistics. Trends in age-specific and age-adjusted incidence and mortality rates, rate ratios and stage at diagnosis were examined for Arab and Jewish women during 1979-2002. Five-year survival rates for 1995-1999 were compared by stage. Among Arab women, age-adjusted incidence rates increased by 202.1%, from 14.1 per 100,000 in 1979-1981 to 42.6 in 2000-2002. Among Jewish women, the rates increased by 45.7%, from 71.1 per 100,000 women in 1979-1981 to 103.6 in 2000-2002. Incidence to mortality rate ratio increased for both population groups, but it is still lower among Arab women. In every age group, Arab women were more likely to be diagnosed at a more advanced stage of the disease. The rise in breast cancer incidence and mortality rates and the later stage of diagnosis among Arab women emphasize the urgent need for increasing early detection of breast cancer in the Arab population by improving rates of compliance with screening mammography.

Tumor antigen-based immunotherapy and immunoprevention of cancer

Any approach to the treatment and prevention of cancer must face the daunting reality that each cancer may be as individual as the patient in whom it has evolved. The challenge is also to develop a therapy that would eradicate that which is abnormal while preserving what is normal. For many years, therapies have been sought that could target a specific abnormal cancerous processes, such as rapid division or increased vascular flow, but with only limited success. Unfortunately, these successes have also been accompanied by varying degrees of toxicity and there is currently no standard therapy that can eradicate clinical disease and prevent recurrence while leaving normal tissue unharmed. However, approaches directed towards manipulating tumor-specific immunity hold promise for effective treatment and lasting cure. These approaches are based on the exceptional specificity of the immune system, the potential for long-term protective memory, and the accumulated evidence that affected individuals have spontaneous immune responses against their own tumors.