Effects of lead time, length bias, and false-negative assurance on screening for breast cancer

Breast Microcalcifications Studied with 3d Contrast-enhanced High-field Magnetic Resonance Imaging: More Accuracy in the Diagnosis of Breast Cancer

Aims

To evaluate the reliability of magnetic resonance imaging (MRI) performed with three-dimensional (3D) sequences in mammographically detected breast microcalcifications.

Methods

During an 8-month period, a group of 28 patients with mammographically detected microcalcifications suspicious for malignancy underwent MRI. Their ages ranged from 33 to 65 years. Examinations were performed with a 1.5 Tesla MR unit and a 3D T1 weighted sequence. Images were interpreted on the basis of morphologic parameters and dynamic behavior in the uptake of contrast medium (Gd-DTPA). Histologic findings were considered as the gold reference.

Results

Histologic analysis revealed invasive carcinoma in 7 patients, 3 of which were associated with foci of lobular carcinoma in situ. Intraductal carcinoma was diagnosed in 8 patients, 1 of which was associated with a tubular carcinoma. Benign lesions accounted for 13 patients. All the neoplastic conditions showed enhancement on MR images (sensitivity, 100%), whereas early and intense enhancement was noted in 5 of 13 benign lesions (specificity, 61%). The positive predictive value was 75% and negative predictive value, 100%.

Conclusions

Although an overlap in the enhancement behavior of malignant and some benign lesions is clearly evident, a careful interpretation of MR images is helpful in detecting and mainly ruling out breast cancer combined with mammographically suspicious microcalcifications.

Growing incidence of thyroid carcinoma in recent years: Factors underlying overdiagnosis

There is an increasing incidence of well-differentiated thyroid cancer worldwide. Much of the increase is secondary to increased detection of small, low-risk tumors, with questionable clinical significance. This review addresses the factors that contribute to the increasing incidence and considers environmental, and patient-based and clinician-led influences. Articles addressing the causes of the increased incidence were critically reviewed. A complex interplay of environmental, medical, and social pressures has resulted in increased awareness of the thyroid disease risk, increased screening of thyroid cancers, and increased diagnosis of thyroid cancers. Although there is evidence to suggest that the true disease incidence may be changing slightly, most of the increase is related to factors that promote early diagnosis of low-risk lesions, which is resulting in a significant phenomenon of overdiagnosis. An improved understanding of these pressures at a global level will enable healthcare policymakers to react appropriately to this challenge in the future.

MuSIC report III: tumour microcirculation patterns and development of metastasis in long-term follow-up of melanocytic uveal tumours

PURPOSE

To statistically determine differences in microcirculation patterns between nevi and uveal melanomas and the influence of these patterns on metastatic potential in the long-term follow-up of 112 patients with melanocytic uveal tumours. In vivo markers indicating malignancy and metastatic potential have implications for treatment decision.

METHODS

Primary diagnosis and work-up included clinical examination, fundus photography, standardized A and B scan echography as well as evaluation of tumour microcirculation patterns via confocal fluorescein and indocyanine green angiography (ICGA). Patient data were collected from the patient files, the tumour registry or personal contact. Statistical analysis was performed with spss 22.0 using chi-square, Fisher's exact test and Kaplan-Meier survival analysis.

RESULTS

Forty-three uveal melanocytic lesions remained untreated and were retrospectively classified as benign nevi, whereas 69 lesions were malignant melanomas (T1: 32, T2: 28, T3: 6 and T4: 3). 'Silent' and 'arcs without branching' were found significantly more often in nevi (p = 0.001 and p = 0.010), whereas 'parallel with cross-linking' and 'networks' were significantly more frequent in melanomas (p = 0.022 and p = 0.029). The microcirculation pattern 'parallel with cross-linking' proved significantly more frequent in patients who developed metastases (p = 0.001).

CONCLUSIONS

Certain microcirculation patterns may guide us in differentiating uveal nevi from malignant melanomas. A non-invasive prognostic marker can be of great value for borderline lesions in which cytology is less likely taken. 'Parallel with cross-linking' did not only indicate malignancy, but it was also associated with later tumour metastasis.

Effect of implementation of the mass breast cancer screening programme in older women in the Netherlands: population based study

OBJECTIVE

To assess the incidence of early stage and advanced stage breast cancer before and after the implementation of mass screening in women aged 70-75 years in the Netherlands in 1998.

DESIGN

Prospective nationwide population based study.

SETTING

National cancer registry, the Netherlands.

PARTICIPANTS

Patients aged 70-75 years with a diagnosis of invasive or ductal carcinoma in situ breast cancer between 1995 and 2011 (n=25,414). Incidence rates were calculated using population data from Statistics Netherlands.

MAIN OUTCOME MEASURE

Incidence rates of early stage (I, II, or ductal carcinoma in situ) and advanced stage (III and IV) breast cancer before and after implementation of screening. Hypotheses were formulated before data collection.

RESULTS

The incidence of early stage tumours significantly increased after the extension for implementation of screening (248.7 cases per 100,000 women before screening up to 362.9 cases per 100,000 women after implementation of screening, incidence rate ratio 1.46, 95% confidence interval 1.40 to 1.52, P<0.001). However, the incidence of advanced stage breast cancers decreased to a far lesser extent (58.6 cases per 100,000 women before screening to 51.8 cases per 100,000 women after implementation of screening, incidence rate ratio 0.88, 0.81 to 0.97, P<0.001).

CONCLUSIONS

The extension of the upper age limit to 75 years has only led to a small decrease in incidence of advanced stage breast cancer, while that of early stage tumours has strongly increased.

Screening mammography benefit controversies: sorting the evidence

Numerous clinical studies have confirmed that screening women age 40 years and older reduces breast cancer mortality by 30% to 50%. Several factors including faster breast cancer growth rates and lower breast cancer incidence among younger women, as well as shorter life expectancy and more comorbid conditions among older women, should also be considered in screening guidelines. Annual screening beginning at age 40 years and continuing with no upper age limit, as long as a woman has a life expectancy of at least 5 years and no significant comorbid conditions, is currently recommended.

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

Consensus recommendations for advancing breast cancer: risk identification and screening in ethnically diverse younger women

A need exists for a breast cancer risk identification paradigm that utilizes relevant demographic, clinical, and other readily obtainable patient-specific data in order to provide individualized cancer risk assessment, direct screening efforts, and detect breast cancer at an early disease stage in historically underserved populations, such as younger women (under age 40) and minority populations, who represent a disproportionate number of military beneficiaries. Recognizing this unique need for military beneficiaries, a consensus panel was convened by the USA TATRC to review available evidence for individualized breast cancer risk assessment and screening in young (< 40), ethnically diverse women with an overall goal of improving care for military beneficiaries. In the process of review and discussion, it was determined to publish our findings as the panel believes that our recommendations have the potential to reduce health disparities in risk assessment, health promotion, disease prevention, and early cancer detection within and in other underserved populations outside of the military. This paper aims to provide clinicians with an overview of the clinical factors, evidence and recommendations that are being used to advance risk assessment and screening for breast cancer in the military.

Genomic and epigenomic integration identifies a prognostic signature in colon cancer

PURPOSE

The importance of genetic and epigenetic alterations maybe in their aggregate role in altering core pathways in tumorigenesis.

EXPERIMENTAL DESIGN

Merging genome-wide genomic and epigenomic alterations, we identify key genes and pathways altered in colorectal cancers (CRC). DNA methylation analysis was tested for predicting survival in CRC patients using Cox proportional hazard model.

RESULTS

We identified 29 low frequency-mutated genes that are also inactivated by epigenetic mechanisms in CRC. Pathway analysis showed the extracellular matrix (ECM) remodeling pathway is silenced in CRC. Six ECM pathway genes were tested for their prognostic potential in large CRC cohorts (n = 777). DNA methylation of IGFBP3 and EVL predicted for poor survival (IGFBP3: HR = 2.58, 95% CI: 1.37-4.87, P = 0.004; EVL: HR = 2.48, 95% CI: 1.07-5.74, P = 0.034) and simultaneous methylation of multiple genes predicted significantly worse survival (HR = 8.61, 95% CI: 2.16-34.36, P < 0.001 for methylation of IGFBP3, EVL, CD109, and FLNC). DNA methylation of IGFBP3 and EVL was validated as a prognostic marker in an independent contemporary-matched cohort (IGFBP3 HR = 2.06, 95% CI: 1.04-4.09, P = 0.038; EVL HR = 2.23, 95% CI: 1.00-5.0, P = 0.05) and EVL DNA methylation remained significant in a secondary historical validation cohort (HR = 1.41, 95% CI: 1.05-1.89, P = 0.022). Moreover, DNA methylation of selected ECM genes helps to stratify the high-risk stage 2 colon cancers patients who would benefit from adjuvant chemotherapy (HR: 5.85, 95% CI: 2.03-16.83, P = 0.001 for simultaneous methylation of IGFBP3, EVL, and CD109).

CONCLUSIONS

CRC that have silenced genes in ECM pathway components show worse survival suggesting that our finding provides novel prognostic biomarkers for CRC and reflects the high importance of integrative analyses linking genetic and epigenetic abnormalities with pathway disruption in cancer.

A meta-analysis of the clinical effectiveness of school scoliosis screening

STUDY DESIGN

A meta-analysis that systematically reviewed the evaluation studies of a scoliosis screening program reported in the literature.

OBJECTIVE

To evaluate the best current evidence on the clinical effectiveness of school screening for adolescent idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

The use of school scoliosis screening is controversial, and its clinical effectiveness has been diversely reported.

METHODS

Data sources included 3 databases, namely, PubMed, Google scholar, CINAHL database, and the references from identified reviews and studies. Studies were included if: (1) they adopted a retrospective cohort design; (2) were screened using either the forward bending test (FBT), angle of trunk rotation, or Moiré topography; (3) reported results of screening tests and radiographic assessments; (4) screened adolescents only; (5) reported the incidence of curves with a minimum Cobb angle of 10 degrees or greater; and (6) reported the number of referrals for radiography. Reviews, comments, case studies, and editorials were excluded.

RESULTS

Thirty-six studies, including 34 from the 775 initially identified studies and 2 from the references, met the selection criteria. The pooled referral rate for radiography was 5.0%, and the pooled positive predictive values for detecting curves > or =10 degrees , curves > or =20 degrees , and treatment were 28.0%, 5.6%, and 2.6%, respectively. There was substantial heterogeneity across studies. Meta-regression showed that programs using the FBT alone reported a higher referral rate (odds ratio [OR] = 2.91) and lower positive predictive values for curves > or =10 degrees (OR = 0.49) and curves > or =20 degrees (OR = 0.34) than programs using other tests. Only one small study followed students until skeletal maturity and reported the sensitivity of screening; however, the specificity was not reported. No severe publication bias was noted.

CONCLUSION

The use of the FBT alone in school scoliosis screening is insufficient. We need large, retrospective cohort studies with sufficient follow-up to properly assess the clinical effectiveness of school scoliosis screening.

Upper endoscopy as a screening and surveillance tool in esophageal adenocarcinoma: a review of the evidence

Esophageal adenocarcinoma is a rare cancer that is increasing rapidly in incidence. Because gastroesophageal reflux disease (GERD) is a risk factor for the development of this cancer, endoscopic screening of individuals with GERD symptoms and endoscopic surveillance of those who are found to have Barrett's esophagus (BE), the presumed precursor to adenocarcinoma, have been proposed. Although no direct data support endoscopic screening or surveillance, several lines of indirect evidence are available. We apply a set of criteria for the evaluation of screening programs to endoscopic screening of subjects with reflux and endoscopic surveillance of subjects with BE. A critical examination of the data supporting these practices shows that considerable gaps exist in our knowledge regarding endoscopy as a screening test in GERD, making us unable to support this practice based on current evidence. Although no controlled trials exist to substantiate the effectiveness of surveillance programs for subjects with BE, some stronger indirect evidence does support this practice. However, further studies are necessary to substantiate the effectiveness and cost-effectiveness of endoscopic surveillance in BE. Based on the currently available data, consideration should be given to expanding the intervals between endoscopic surveillance sessions.

Screening mammography: proven benefit, continued controversy

Screening mammography, despite its limitations, remains the best means for diagnosing breast cancer in asymptomatic women. Regarding the continuing controversies concerning the age at which screening should start, evidence supports beginning regular screening at age 40 in women at average risk . Similarly, evidence suggests that the screening interval should be yearly, especially in younger women. Rather than an arbitrary age at which screening should stop, the decision on screening elderly women should be made on an individual basis, taking into account level of health and life expectancy. More work needs to be done on determining the optimum screening strategies for high-risk women. As to the interpretation of screening mammography, a certain level of observer variability and of false-negative and false-positive readings are inherent in the process. These should be kept to a minimum through efforts by the interpreting radiologist to improve performance through auditing of individual results and continuing education. The impact of double reading and computer-aided detection in the interpretation of screening mammograms warrants further evaluation in terms of efficacy and cost-effectiveness. Despite these continuing controversies, mortality from breast cancer in the United States has been decreasing steadily for the past 25 years. The magnitude of the decrease has been reported to range from 8% to 25%. Although some of this decrease may be attributable to improvements in the treatment of breast cancer, early detection through screening mammography has undoubtedly played a role in this mortality reduction. The controversies that surround the issue of screening should not detract from the fact that screening mammography has proved to save lives.

Routine follow-up examinations in breast cancer patients have minimal impact on life expectancy: a simulation study

BACKGROUND

Little is known about the effects of routine follow-up examinations on life expectancy in cancer patients. Lately, the benefits of follow-up examinations have been debated, which has given rise to less extensive, though still frequent, follow-up strategies. In this study, a simulation model was applied to evaluate the impact of different follow-up strategies on life expectancy in breast cancer patients.

MATERIALS AND METHODS

A five-state Markov chain model was developed, with which various follow-up strategies with regard to frequency and elaborateness were simulated. Calculations were based on a hypothetical population of breast cancer patients treated with curative intent. Medical aspects were studied, such as life expectancy and the proportion of patients who died from breast cancer. Social and psychological aspects and quality of life were not taken into account. Data from the literature were used to estimate the parameters needed for the model.

RESULTS

The gain in life expectancy with standard follow-up compared to no follow-up examination, was about 2 months in breast cancer patients aged 50 years treated with curative intent. The percentage of patients who died from breast cancer was 45.4% with standard follow-up, versus 45.8% without follow-up. In older women, the gain was even less. Sensitivity analyses showed that the effects on life expectancy were robust.

CONCLUSIONS

Our model showed that standard follow-up had minimal impact on the prognosis of breast cancer patients. It may be unnecessary to continue standard follow-up by medical specialists after the end of the surveillance period of the primary therapy, provided that the patients continue to have easy access to health care facilities in the case of symptoms or concern. However, future research is needed to study quality of life aspects of follow-up.

Telemammography: implementation issues

Telemammography has the potential to improve access to centralized expertise for the interpretation of breast imaging studies. Digital mammography has more demanding spatial resolution requirements than other forms of medical imaging because of the need to detect microcalcifications, the fine details of lesion margins, and subtle architectural distortion. The resolution requirements for mammography have important implications for image acquisition and display technologies. The large size of the resulting image data sets places significant demands on local and wide area networks as well as storage media. Image data compression will be particularly important for telemammography to help make systems practical and affordable. This article describes how existing technologies can be adapted to implement telemammography systems in the near future.

Breast cancer screening

Breast cancer is the most common malignancy among women in the United States; however, recent data demonstrates a decline in the mortality rate, which may be attributed to early detection from screening programs combined with effective therapies for early stage disease. As a result of the prevalence of breast cancer and its association with highly emotional issues, screening recommendations have aroused debate in the scientific, public, and legislative domains. A general consensus supports breast cancer screening among women between the ages of 50 and 70; however, much controversy exists regarding screening for women age 40 to 49 or above age 70. This article explores the issues involved in determining breast cancer screening recommendations among asymptomatic women with average risk in the United States.

Fractal analysis of mammographic lesions: a prospective, blinded trial

Mammography has become the mainstay of breast cancer screening. However, widespread mammography has led to an increase of the number of breast biopsies done for benign disease. Therefore, a method to better discriminate benign from malignant lesions is needed. Fractal analysis is a mathematical method which can quantify complex shapes. It has been previously shown retrospectively that the composite fractal dimensions, D, of malignant mammographic masses is higher than for benign lesions. A prospective study of 75 patients who were recommended to undergo needle localized breast biopsy by independent radiologists had the composite D calculated. Fractal analysis was done without knowledge of the biopsy results. The mean composite D of malignant lesions was higher than benign lesions, 2.545+/-0.067 vs. 1.936+/-0.144 (p=0.00004). Calculation of a receiver-operating characteristic curve showed that a cutoff value of 2.067 had a 100% sensitivity and 63 % specificity (i.e., false positive rate of 37%). Mean D for fibroadenomas was 2.087+/-0.054, fibrocystic disease was 1.877+/-0.167, DCIS was 2.261+/-0.069, and invasive cancer was 2.634+/-0.039 (1-way ANOVA, p=0.00007). These data imply that fractal analysis may be beneficial in discriminating between benign and malignant lesions. However, further study in a larger number of patients with a variety of lesions is needed.

Survival of women ages 40-49 years with breast carcinoma according to method of detection

BACKGROUND

The value of mammographic screening in reducing breast carcinoma mortality among women younger than 50 years continues to be controversial. Previous randomized clinical trials have not been definitive because of inadequate sample sizes, prolonged screening intervals, questionable randomization, and/or cross-contamination between intervention groups. This study uses a historical prospective cohort design to examine differences in prognostic factors at the time of breast carcinoma diagnosis and differences in overall survival among patients ages 40-49 years, according to the method of breast carcinoma detection.

METHODS

Women (n = 971) ages 40-49 years diagnosed with invasive breast carcinoma between 1986 and 1992 were identified by TUMORS (The Upper Midwest Oncology Registry Services). Measures of tumor size, lymph node status, and overall survival were compared with breast carcinoma patients whose tumors were detected by breast self-exam (BSE), clinical breast exam (CBE), patient incidental finding (PI), or mammography.

RESULTS

Mean tumor size among women in the mammography group was smaller than that among women in the BSE, CBE, and PI groups (P < 0.002). Tumors detected by mammography were significantly more likely to be localized than those detected by other methods (P < 0.0001). Patients whose tumors were detected by mammography had significantly better survival than patients in the other detection method groups, especially among those with smaller tumors (P < 0.0001). This difference persisted even after adjustment for lead time bias.

CONCLUSIONS

Women ages 40-49 years whose invasive breast carcinoma is detected by mammography have significantly smaller tumors, more localized disease, and may have a lower risk of mortality than women whose tumors are detected by other methods.

Immediate biopsy versus observation for abnormal findings on mammograms: an analysis of potential outcomes and costs

BACKGROUND

The increased usage of screening mammography has led to an increase in the number of needle localized breast biopsies. The perceived low yield of the biopsies has caused concern about the costs and effectiveness of this procedure. Arguments have centered on what is the appropriate true-positive rate for screening mammography, and which abnormal findings may be observed rather than tested immediately.

METHODS

A decision analysis was done to help answer these questions. Factors evaluated included age of patient at discovery of abnormal finding, the rate of follow-up mammograms eventually requiring biopsy, the potential effects of tumor-doubling time on increasing the stage of disease, quality-of-life issues, and costs.

RESULTS

For an average 50-year-old woman the quality-adjusted life expectancy (QALE) was longer for immediate biopsy by 0 to 3 years, depending on the assumptions on tumor-doubling time; however, immediate biopsy increased the cost per patient from $700 to $900. The QALE was also superior for immediate biopsy if more than 30% of follow-up mammograms required biopsy, and immediate biopsy was more cost effective if more than 36% of follow-up mammograms required biopsy. Patient age did not affect the superiority of immediate biopsy over observation, although quality-of-life issues did.

CONCLUSIONS

Those lesions with a greater than 20% to 30% probability of being malignant, or lesions with potentially short doubling times, should undergo immediate biopsy. Lesions judged to be at lower risk may be observed for 6 months. Either of these recommendations should be adjusted depending on an individual patient's quality-of-life concerns.

Efficacy of breast cancer screening by age. New results from the Swedish Two-County Trial

BACKGROUND

Several studies have found a smaller effect of breast cancer screening on breast cancer mortality in women aged younger than 50 years compared with older women. Various possible reasons have been suggested for this, but none firmly is established.

METHODS

The Swedish Two-County Study is a randomized trial of breast cancer screening of women aged 40-74 years, comprising with 133,065 women with a 13-year follow-up of 2467 cancers. The Breast Cancer Detection Demonstration Project (BCDDP) is a nonrandomized screening program in the United States, with a 14-year follow-up of 3778 cancers in women aged 40-74 years. The Swedish results by age were updated. The lesser effect of screening at ages 40-49 years was investigated in terms of sojourn time (the duration of the preclinical but detectable phase) size, lymph node status, and histologic type of the tumors diagnosed in the Swedish Study and their subsequent effect on survival using survival data from both studies.

RESULTS

In the Swedish Trial, a 30% reduction in mortality associated with the invitation to screening of women aged 40-74 years was maintained after 13-years of follow-up. The reduction was 34% for women aged 50-74 years and 13% for women aged 40-49 years. Results indicated that the reduced effect on mortality for women aged 40-49 years was due to a differential effect of screening on the prognostic factors of tumor size, lymph node status, and histologic type. The mean sojourn times in the age groups 40-49 years, 50-59 years, 60-69 years, and 70-74 years were 1.7, 3.3, 3.8, and 2.6 years, respectively.

CONCLUSIONS

These results suggest that much, although not all, of the smaller effect of screening on mortality in women aged 40-49 years is due to faster progression of a substantial proportion of tumors in this age group and the rapid increase in incidence during this decade of life. It is concluded that the interval between screenings should be shortened to achieve a greater benefit in this age group. It is estimated that a 19% reduction in mortality would result from an annual screening regime.

MBS: a model for risk benefit analysis of breast cancer screening

Breast cancer screening programmes employing mammography are being implemented in various European countries. Different screening protocols are used in demonstration projects and nationwide programmes. To evaluate and improve protocols, a computer model for the evaluation of breast cancer screening has been developed. The availability of such a model can be of great importance in obtaining a better insight into the influence of various parameters. The Monte Carlo computer model is based on random selection from distributions of relevant parameters including tumour onset, tumour growth rate, lifetime expectancy, tumour detection size for screening and spontaneous observation. The radiation risk is calculated for various screening protocols employing multiplicative and additive risk models combined with lifetime expectancy, number of females screened and absorbed dose per screening session. The benefit is calculated on the basis of the reduction in tumour size at detection due to screening compared with spontaneous observation and the survival as a function of tumour diameter. Data from the Swedish two-county study are used to validate the model in terms of prevalence, interval tumour rates and interval tumour diameter distributions. Except for the spontaneous tumour diameter distribution, the model can describe the Swedish two-county study. Specific information is presented on the distributions of relevant parameters.