Efficacy of breast-cancer screening for female relatives of breast-cancer-index cases: Taiwan multicentre cancer screening (TAMCAS)

Evaluating clinical efficacy of hospital-based surveillance with mammography and ultrasonography for breast cancer

Periodic mammography and/or sonography examinations are conducted across numerous hospitals nationalwidely, especially for antedees with a positive mammography screening. Despite the regular practice, clinical efficacy of hospital-based breast cancer surveillance remains unclear. Specifically, the impact of surveillance interval upon survival and prognostic surrogates stratified by menopausal status, as well as malignant transition rate should be deciphered. We retrieved cancer registry to ascertain 841 breast cancers with surveillance history through administration data. Healthy controls underwent breast surveillance and were concurrently free of cancer. More benign diseases rather than cancers were identified from premenopausal women (age ≤50 years) with sonography alone within one year, as well as older women (age >50) with both mammography and sonography one to two years before a cancer or benign diagnosis. Among breast cancers, mammography alone during the antecedent one to two years had a protective effect for diagnosing carcinoma in situ rather than invasive cancer (age-adjusted odds ratio: 0.048, P = 0.016). Three-state time homogeneous Markov model showed that hospital-based breast surveillance within 2 years of disease onset reduced the malignant transition rate by 65.16% (59.79-76.74%). The clinical efficacy of breast cancer surveillance was evidenced.

Birth Cohort Effects in Breast Cancer Incidence: Global Patterns and Trends

Breast cancer is the most common neoplasm in the world among women. The age-specific incidences and onset ages vary widely between Asian and Western countries/regions. Invasive breast cancer cases among women from 1997 to 2011 were abstracted from the International Agency for Research on Cancer and the Taiwan Cancer Registry. Age-period-cohort analysis was performed to examine the trends. The cohort effect was prominent in South Korea, Taiwan, Japan, and Thailand, possibly related to the timing of westernization. The risk of breast cancer initially rose with the birth cohorts in Hong Kong and India (both former British colonies), peaked, and then declined in recent birth cohorts. Unlike other Asian countries/regions, virtually no birth cohort effect was identified in the Philippines (a Spanish colony in 1565 and the first Asian country to adopt Western cultural aspects). Moreover, an at-most negligible birth cohort effect was identified for all ethnic groups (including Asian immigrants) in the United States. This global study identified birth cohort effects in most Asian countries/regions but virtually no impact in Western countries/regions. The timing of westernization was associated with the birth cohort effect.

Accuracy of clinical diagnosis, mammography and ultrasonography in preoperative assessment of breast cancer

BACKGROUND

Cancer of the breast is the most common malignancy affecting women in many parts of the world. Its early detection has, therefore, become necessary to reduce morbidity and mortality from the disease. In sub-Saharan Africa, radiological imaging, histology and management programs are associated with challenges.

OBJECTIVES

This study seeks to assess the validity of clinical diagnosis, mammography and breast ultrasonography in the preoperative assessment of suspected breast cancer patients for accurate detection of the disease to enable appropriate management.

METHODS

A prospective cross-sectional study was carried out in the Radiology Department of Komfo Anokye Teaching Hospital, Kumasi, Ghana, between November 2007 and July 2008 with a sample size of 103. All patients with a clinical suspicion of breast cancer who gave informed consent were recruited, underwent bilateral mammography and whole breast ultrasonography and then biopsy for all BIRADS categories 4 or 5 lesions. The histopathology results were retrieved to complete the study.

RESULT

In this study the definition of malignancy was made using histology as the gold standard. A total of 103 patients were recruited for this study with mean age of 55(±15) years, out of which 52 (50.5%) had malignant lesions. The overall sensitivity of clinical diagnosis was 50.5%. While the overall sensitivity and specificity for mammogram and ultrasound were 73.0%, 80.0% and 100%, 80.4% respectively.

CONCLUSION

In conclusion, this study has demonstrated that clinical diagnosis, ultrasound and mammography can potentially predict breast cancer disease with considerable sensitivity and specificity.

FUNDING

Not declared.

Effect of mammography screening on stage at breast cancer diagnosis: results from the Korea National Cancer Screening Program

In Asian countries, breast densities and the proportion of younger women with breast cancer are higher than those in Western countries. This study was designed to determine differences in stage at diagnosis of breast cancer among Korean women according to screening history. The study population was derived from the Korea National Cancer Screening Program (KNCSP). The study cohort comprised 17,689 women who were newly diagnosed with breast cancer in 2011 and were invited to undergo breast cancer screening via the KNCSP between 2002 and 2011. Ductal carcinoma in situ (DCIS) and localized breast cancer were most frequent in both ever-screened and never-screened patients. Late stage cancer was significantly more frequent in never-screened patients, compared with ever-screened patients. Compared to never-screened women, the odds ratio (OR) for being diagnosed with early stage breast cancer among screened women was 1.41 (95% Confidence Interval [CI] = 1.28–1.55). The OR for being diagnosed with early stage breast cancer was highest among patients who underwent screening three times or more (aOR = 1.89, 95% CI = 1.57–2.29). Screening by mammography was associated with diagnosis of early stage breast cancer in Korean women. However, significant increases in the diagnosis of DCIS and localized breast cancers among ever-screened patients suggest the possibility of overdiagnosis due to screening.

Hospitalization for Inflammatory Bowel Disease is Associated with Increased Risk of Breast Cancer: A Nationwide Cohort Study of an Asian Population

PURPOSE

To learn whether women with inflammatory bowel disease (IBD) exhibit a higher risk of breast cancer.

METHODS

We identified 4,856 women with IBD symptoms from 1998 to 2008 and 19,424 control patients without the disorder, frequency matched by age, sex, and admission year. Both cohorts were followed-up until the end of 2010 to estimate the risk of breast cancer.

RESULTS

Overall, the incidence of breast cancer was similar in the IBD and control cohorts (1.31 vs. 1.25 per 1,000 person-years). The adjusted hazard ratio of breast cancer was 0.95 (95 % confidence interval 0.66-1.36) for the IBD patients. Further analysis revealed that neither Crohn disease nor ulcerative colitis was associated with the risk of developing breast cancer in women. The age-specific analysis indicated that the incidence of breast cancer was highest in the 45- to 65-year-old age group in both cohorts. The incidence of breast cancer was significantly increased in patients who required hospitalization twice or more per year, compared with the control cohort (adjusted hazard ratio 8.45; 95 % confidence interval 4.64-15.4). Moreover, age-specific analysis showed that patients aged less than 65 years old (≤44 or 45-65 years of age) exhibited a strong association between IBD hospitalization and breast cancer risk.

CONCLUSIONS

The risk of breast cancer was positively proportional to the frequency of admission for IBD. Therefore, careful surveillance of breast cancer should be sought for female IBD patients with 2 or more annual hospitalizations.

Risk assessment of multistate progression of breast tumor with state-dependent genetic and environmental covariates

Few studies have focused on the different roles risk factors play in the multistate temporal natural course of breast cancer. We proposed a three-state Markov regression model to predict the risk from free of breast cancer (FBC) to the preclinical screen-detectable phase (PCDP) and from the PCDP to the clinical phase (CP). We searched the initiators and promoters affecting onset and subsequent progression of breast tumor to build up a three-state temporal natural history model with state-dependent genetic and environmental covariates. This risk assessment model was applied to a 1 million Taiwanese women cohort. The proposed model was verified by external validation with another independent data set. We identified three kinds of initiators, including the BRCA gene, seven single nucleotides polymorphism, and breast density. ER, Ki-67, and HER-2 were found as promoters. Body mass index and age at first pregnancy both played a role. Among women carrying the BRCA gene, the 10-year predicted risk for the transition from FBC to CP was 25.83%, 20.31%, and 13.84% for the high-, intermediate-, and low-risk group, respectively. The corresponding figures were 1.55%, 1.22%, and 0.76% among noncarriers. The mean sojourn time of staying at the PCDP ranged from 0.82 years for the highest risk group to 6.21 years for the lowest group. The lack of statistical significance for external validation (x(4)2=5.30,p=0.26) revealed the adequacy of our proposed model. The three-state model with state-dependent covariates of initiators and promoters was proposed for achieving individually tailored screening and also for personalized clinical surveillance of early breast cancer.

Individually tailored screening of breast cancer with genes, tumour phenotypes, clinical attributes, and conventional risk factors

Background:

We demonstrated how to comprehensively translate the existing and updated scientific evidence on genomic discovery, tumour phenotype, clinical features, and conventional risk factors in association with breast cancer to facilitate individually tailored screening for breast cancer.

Methods:

We proposed an individual-risk-score-based approach that translates state-of-the-art scientific evidence into the initiators and promoters affecting onset and subsequent progression of breast tumour underpinning a novel multi-variable three-state temporal natural history model. We applied such a quantitative approach to a population-based Taiwanese women periodical screening cohort.

Results:

Risk prediction for pre-clinical detectable and clinical-detected breast cancer was made by the two risk scores to stratify the underlying population to assess the optimal age to begin screening and the inter-screening interval for each category and to ascertain which high-risk group requires an alternative image technique. The risk-score-based approach significantly reduced the interval cancer rate as a percentage of the expected rate in the absence of screening by 30% and also reduced 8.2% false positive cases compared with triennial universal screening.

Conclusion:

We developed a novel quantitative approach following the principle of translational research to provide a roadmap with state-of-the-art genomic discovery and clinical parameters to facilitate individually tailored breast cancer screening.

Optimal two-stage breast cancer screening for countries with intermediate or low incidence of breast cancer

OBJECTIVES

This study is to identify an optimal cut-off for two-stage breast cancer screening making allowance for variation of the baseline incidence rate and utility values between sensitivity and specificity.

METHODS

We used data from a two-stage breast cancer screening of Taiwanese women aged 50-69 years for whom risk stratification was based on a composite risk score (conventional risk factors); subjects with a risk score greater than the cut-off score were screened using mammography. The Bayesian posterior risk for breast cancer was computed by incorporation of the baseline incidence rate and the risk score. Bayes' maximum utility decision rule was then developed to determine the optimal screening cut-off.

RESULTS

With a risk score of -9 applied to the current two-stage breast cancer screening programme, we could detect one breast cancer case for every 1406 women. Given different predetermined risks, the selected cut-offs were -9 for 1:1200, -8 for 1:800, -4 for 1:600, -1 for 1:400 and 3 for 1:200 for women aged 50-59 years. When the regret utility ratio of positive predictive value to negative predictive value was set at 1:10, the specificity and sensitivity were 58.5% and 70.4%, respectively, and the optimal cut-off was -5.5. When the ratio was set at 10:1, the sensitivity and specificity were 75.5% and 57.1%, respectively, and the optimal cut-off value was -7.5.

CONCLUSIONS

This study demonstrates that Bayes' maximum utility decision rule can be used to determine optimal cut-off values for two-stage breast cancer screening in countries or areas with lower or intermediate incidence of breast cancer.

Validation of a modelling approach for estimating the likely effectiveness of cancer screening using cancer data on prevalence screening and incidence

PURPOSE

This study aims to validate a biostatistical approach to predict the likely effectiveness of screening in reducing advanced disease in the absence of data on incident screen and interval cancers.

METHODS

We derived the predicted relative reduction in advanced stage disease following screening from the expected proportion of advanced disease following screening and the observed proportion of advanced disease detected clinically among the controls. We compared the predicted estimates to those observed in a randomised trial.

RESULTS

Using our method, the predicted estimates of relative reduction in node positive breast cancer following screening were comparable to the observed estimates for the age groups 50-59 and 60-69 in the screening study (predicted 32% vs. observed 40% (p=0.274) and predicted 34% vs. observed 45% (p=0.068), respectively). However, for the age groups 40-49 and 70-74 the predicted values were overestimates of the likely effectiveness of screening compared to the observed values (predicted 38% vs. observed 16% (p=0.014) and predicted 34% vs. observed 0% (p=0.001), respectively).

CONCLUSION

When the number of cancer cases is more than hundred, the method of prediction using only prevalence screen data may be accurate. Where cancers are less common, for example in small populations or young age groups, further data from interval cancers or incidence screens may be necessary.

Recent trends and patterns in breast cancer incidence among Eastern and Southeastern Asian women

BACKGROUND

Incidence of breast cancer is rising in Asian countries, and breast cancer is the most common cancer among Asian women. However, there are few recent descriptive reports on the epidemiology of breast cancer among Eastern and Southeastern Asian populations.

METHODS

We examined incidence trends for invasive breast cancer in women aged ≥20 years from 15 registries in Eastern (China, Japan, the Republic of Korea, Taiwan) and Southeastern Asia (the Philippines, Singapore, Thailand) for the period 1993-2002 mainly using data from Cancer Incidence in Five Continents, Volumes VIII and IX. We compared trends in annual incidence rates and age-specific incidence curves over a 10-year period. We also compared the incidence rates of Asian-Americans with the rates of their Asian counterparts.

RESULTS

Breast cancer incidence rates increased gradually over time in all study populations. Rates were relatively high in Southeastern Asia and became progressively lower along a south-to-north gradient, with a fourfold geographic variation within the study populations. Age-specific incidence curves showed patterns that gradually changed according to incidence rates. Breast cancer incidence among Asian women living in the United States was 1.5-4 times higher than the corresponding incidence rate in the women's respective countries of origin.

CONCLUSION

Breast cancer incidence is expected to continue to increase for the next 10 years in Asia and may approach rates reported among Asian-Americans. The number and mean age of breast cancer cases is expected to increase as the female Asian population ages, the prevalence of certain risk factors changes (early menarche, late menopause, low parity, late age at first live birth, and low prevalence of breastfeeding), and as Asian countries introduce mass screening programs.

Secular trends in breast cancer mortality in five East Asian populations: Hong Kong, Japan, Korea, Singapore and Taiwan

Breast cancer risk is increasing in most Asian female populations, but little is known about the long-term mortality trend of the disease among these populations. We extracted data for Hong Kong (1979-2005), Japan (1963-2006), Korea (1985-2006), and Singapore (1963-2006) from the World Health Organization (WHO) mortality database and for Taiwan (1964-2007) from the Taiwan cancer registry. The annual age-standardized, truncated (to > or =20 years) breast cancer death rates for 11 age groups were estimated and joinpoint regression was applied to detect significant changes in breast cancer mortality. We also compared age-specific mortality rates for three calendar periods (1975-1984, 1985-1994, and 1995-2006). After 1990, breast cancer mortality tended to decrease slightly in Hong Kong and Singapore except for women aged 70+. In Taiwan and Japan, in contrast, breast cancer death rates increased throughout the entire study period. Before the 1990s, breast cancer death rates were almost the same in Taiwan and Japan; thereafter, up to 1996, they rose more steeply in Taiwan and then they began rising more rapidly in Japan than in Taiwan after 1996. The most rapid increases in breast cancer mortality, and for all age groups, were in Korea. Breast cancer mortality trends are expected to maintain the secular trend for the next decade mainly as the prevalence of risk factors changes and population ages in Japan, Korea, and Taiwan. Early detection and treatment improvement will continue to reduce the mortality rates in Hong Kong and Singapore as observed in Western countries.

Cost-effectiveness analysis of a two-stage screening intervention for hepatocellular carcinoma in Taiwan

BACKGROUND/PURPOSE

Hepatocellular carcinoma (HCC) has been the leading cause of cancer death in Taiwan since the 1980s. A two-stage screening intervention was introduced in 1996 and has been implemented in a limited number of hospitals. The present study assessed the costs and health outcomes associated with the introduction of screening intervention, from the perspective of the Taiwanese government. The cost-effectiveness analysis aimed to assist informed decision making by the health authority in Taiwan.

METHODS

A two-phase economic model, 1-year decision analysis and a 60-year Markov simulation, was developed to conceptualize the screening intervention within current practice, and was compared with opportunistic screening alone. Incremental analyses were conducted to compare the incremental costs and outcomes associated with the introduction of the intervention. Sensitivity analyses were performed to investigate the uncertainties that surrounded the model.

RESULTS

The Markov model simulation demonstrated an incremental cost-effectiveness ratio (ICER) of NT$498,000 (US$15,600) per life-year saved, with a 5% discount rate. An ICER of NT$402,000 (US$12,600) per quality-adjusted life-year was achieved by applying utility weights. Sensitivity analysis showed that excess mortality reduction of HCC by screening and HCC incidence rates were the most influential factors on the ICERs. Scenario analysis also indicated that expansion of the HCC screening intervention by focusing on regular monitoring of the high-risk individuals could achieve a more favorable result.

CONCLUSION

Screening the population of high-risk individuals for HCC with the two-stage screening intervention in Taiwan is considered potentially cost-effective compared with opportunistic screening in the target population of an HCC endemic area.

Estimation of natural history parameters of breast cancer based on non-randomized organized screening data: subsidiary analysis of effects of inter-screening interval, sensitivity, and attendance rate on reduction of advanced cancer

Estimating the natural history parameters of breast cancer not only elucidates the disease progression but also make contributions to assessing the impact of inter-screening interval, sensitivity, and attendance rate on reducing advanced breast cancer. We applied three-state and five-state Markov models to data on a two-yearly routine mammography screening in Finland between 1988 and 2000. The mean sojourn time (MST) was computed from estimated transition parameters. Computer simulation was implemented to examine the effect of inter-screening interval, sensitivity, and attendance rate on reducing advanced breast cancers. In three-state model, the MST was 2.02 years, and the sensitivity for detecting preclinical breast cancer was 84.83%. In five-state model, the MST was 2.21 years for localized tumor and 0.82 year for non-localized tumor. Annual, biennial, and triennial screening programs can reduce 53, 37, and 28% of advanced cancer. The effectiveness of intensive screening with poor attendance is the same as that of infrequent screening with high attendance rate. We demonstrated how to estimate the natural history parameters using a service screening program and applied these parameters to assess the impact of inter-screening interval, sensitivity, and attendance rate on reducing advanced cancer. The proposed method makes contribution to further cost-effectiveness analysis. However, these findings had better be validated by using a further long-term follow-up data.

Annual or biennial mammography screening for women at a higher risk with a family history of breast cancer: prognostic indicators of screen-detected cancers in New South Wales, Australia

OBJECTIVE

This study examined whether offering annual mammography screening for women with the risk factor of a family history of breast cancer resulted in more favorable prognostic indicators of diagnosed cancers than the usual approach of biennial screening.

METHODS

The study involved women aged 50-69 years with a family history of breast cancer, defined as having > or = 1 first-degree relative diagnosed with breast cancer, who were diagnosed with a screen-detected invasive breast cancer between 1998 and 2004 in BreastScreen New South Wales (n = 590). The women were grouped according to whether they screened in an area offering annual screening to women with a family history, or were offered the standard biennial screening. The odds of having favorable tumor size, grade, and nodal status prognosis were compared between these screening groups using logistic regression. A comparison group of women without a family history, all offered biennial screening, was also evaluated based on the same area groupings to examine whether any differences were due to the area, rather than the screening interval policy.

RESULTS

Women with a family history who were offered annual screening at BreastScreen NSW were significantly more likely than those who were offered biennial screening to be diagnosed with a tumor < or = 20 mm in size (adjusted odds ratio (AOR) = 1.91, 95% CI: 1.21-3.02), and to have a node-negative tumor (AOR = 1.61, 95% CI: 1.03-2.50). There were also significantly higher odds of being diagnosed with tumors < or = 15 mm (p < 0.001) and < or = 10 mm in size (p = 0.011) in women offered annual screening. There was no significant difference in the odds of a Grade 1 tumor being detected (AOR = 1.26, 95% CI: 0.87-1.81), although the direction of the effect was consistent with that seen for size and nodal status. No significant differences were found in the comparison group of women without a family history.

CONCLUSIONS

Offering annual screening for women aged 50-69 years with a family history of breast cancer significantly increased the odds of being diagnosed with a smaller, node-negative tumors. Further investigation is required to assess whether the improved prognostic indicators translate into significantly better mortality outcomes for women with a family history offered annually screening.

Estimation and prediction system for multi-state disease process: application to analysis of organized screening regime

RATIONALE, AIMS AND OBJECTIVES

The disease progression of cancer and non-malignant chronic disease often involve a multi-state transition. However, estimation of parameters and prediction regarding the multi-state disease process are complex. This study aimed to develop an estimation and prediction system with a computer-assisted software using SAS/SCL as a platform to predict the risk of any outcome arising from the underlying multi-state process with or without the incorporation of individual characteristics.

METHOD

The computer-aided system is first constructed following the theoretical framework of stochastic process. The functions provided in this software include model specification, formulation of likelihood function, parameter estimation, model validation and model prediction. An example of breast cancer screening for a high-risk group in Taiwan was used to demonstrate the usefulness of this software.

RESULTS

The natural history of breast cancer of a three-state disease process has been demonstrated. Two suspected risk factors, late age at first full-term pregnancy and obesity, were considered by the form of the proportional hazard model. Formulation of intensity matrix, likelihood function, assignment of initial values, and parameter constraint and estimation were successfully demonstrated in model specification. Model validation suggested a good fit of the constructed model. The application of model prediction enables one to project the effectiveness of organized screening by different inter-screening intervals from a policy level or from an individual basis.

CONCLUSIONS

A computer-aided estimation and prediction system for multi-state disease process was developed and demonstrated. This system can be applied to data with the property of multi-state transitions in association with events or disease.

BRCA1 and BRCA2: the genetic testing and the current management options for mutation carriers

Approximately 5-10% of breast carcinomas and 10% of ovarian carcinomas are ascribable to a genetic susceptibility. Of these, about 40% are related to genetic mutations in the genes BRCA1 and BRCA2. Despite the increasing demand for genetic testing arising from the patients and their relatives, the genetic testing can be offered yet only to individuals belonging to high-risk families in which the probability that there is a germline mutation in a BRCA gene is high and thus cancer occurrence is likely the expression of a highly penetrant genetic predisposition. In this article, we review how the current knowledge on the biological mechanisms underlying BRCA1 and BRCA2 dysfunction may contribute to the understanding of breast and ovarian cancer predisposition. The most currently employed methods for genetic testing are critically overviewed, together with some indications for the interpretation of the test outcome and the clinical management of mutation carriers.

Analysis of sonographic features for the differentiation of benign and malignant breast tumors of different sizes

OBJECTIVE

To analyze the value of various sonographic features in differentiating benign from malignant breast tumors of different sizes to improve the diagnostic accuracy in small lesions.

METHODS

The sonographic features of 1203 histologically confirmed solid breast lesions were prospectively documented with respect to anteroposterior (AP) diameter/width ratio, shape, margin, echogenicity, echotexture, posterior echo and bilateral refraction sign. The sensitivity, specificity and accuracy of breast ultrasound were calculated for lesions grouped according to size (< or = 1, 1.1-2 and > 2 cm). Univariate and multiple logistic regression analyses including calculation of odds ratios for single sonographic features were used to analyze the significance of the different diagnostic features.

RESULTS

The accuracy of breast sonography in differentiating between benign and malignant tumors < or = 1, 1.1-2 and > 2 cm in size was 75.6%, 86.4% and 88.4%, respectively. Univariate analysis demonstrated that all sonographic features were significant in tumors > or = 1.1 cm. Shape, margin, echogenicity and echotexture were the significant factors in those tumors < or = 1 cm. Multiple logistic regression analysis demonstrated that margin, shape, posterior echo and echogenicity were the significant factors for differential diagnosis in tumors > 2 cm. Echogenicity, margin, shape, bilateral refraction sign and echotexture were the significant factors for tumors 1.1-2 cm. On multiple regression analysis, margin was the only significant factor for tumors < or = 1 cm.

CONCLUSION

Tumor margin is the most important sonographic feature in evaluating breast lesions in any size group. With the combination of significant factors and emphasis on specific features according to size of lesion, the diagnostic accuracy of ultrasound for the differential diagnosis of malignant and benign tumors may be improved.

MRI screening for breast cancer in women with familial or genetic predisposition: design of the Dutch National Study (MRISC)

Mammography screening of women aged 50-70 years for breast cancer has proven to be effective in reducing breast cancer mortality. There is no consensus about the value of breast cancer screening in women aged 40-49 years. Five to ten per cent of all breast cancers are hereditary. One of the options to reduce the risk of breast cancer mortality for women with a familial or genetic predisposition is intensive surveillance. However, the effectiveness of mammography screening for breast cancer in these women, who are mainly younger than 50 years, is unproven. MRI might increase the effectiveness of screening in women with a familial or genetic predisposition. This paper describes the design of the Dutch national study for Magnetic Resonance Imaging (MRI) screening in women with a familial or genetic predisposition. The aims of this study are to investigate: the value of regular surveillance in women with a familial or genetic predisposition for breast cancer, the efficacy of MRI as compared to mammography, cost-effectiveness of regular screening and quality of life during surveillance. Included are women with a lifetime risk of familial breast cancer of 15% or more or BRCA1/2 mutation carriers, who visit one of the Dutch family cancer clinics. The aim is to include 2,500 women. The study started on 1 November 1999. On 1 January 2002, more than 1,700 women, including 210 proven carriers of a BRCA1 or BRCA2 mutation, were included in the study.

Sonographic differentiation of invasive and intraductal carcinomas of the breast

The purpose of this study is to evaluate the diagnostic ability of ultrasound and define the sonographic features of symptomatic intraductal and invasive breast carcinoma. To achieve this the ultrasound features of 488 invasive carcinomas and 65 non-screening detected intraductal carcinomas were compared retrospectively. The features included size, AP/W (anteroposterior diameter/width) ratio, shape, margin, internal echogenicity, internal echotexture, posterior acoustic transmission, bilateral edge shadowing sign and calcifications. The sensitivity and specificity of the detection of calcifications by ultrasound in comparison with mammography were also studied. The accuracy of ultrasound diagnosis is 92.0% for invasive carcinoma of breast and 84.8% for intraductal carcinoma. Differentiation of ultrasound features of intraductal and invasive carcinoma can be based on the internal hypoechogenicity, loss of bilateral edge shadowing, posterior acoustic transmission, irregular shape and non-uniform internal echotexture with odds ratio of 0.3, 0.3, 0.4, 0.5 and 0.5, respectively. Internal echogenicity was the only significant differentiating factor on multiple logistic regression analysis. Non-comedo type ductal carcinoma in situ can be differentiated from comedo type by irregular shape with odds ratio of 0.3. The sensitivity, specificity and accuracy rate for the detection of calcifications in invasive carcinomas by ultrasound were 65.1%, 61.9% and 63.2%; in comedo type intraductal carcinoma 62.5%, 66.7% and 63.6%, and in non-comedo type intraductal carcinoma 30.0%, 86.7% and 64.0%, respectively. The ultrasound appearance of non-screening detected intraductal carcinoma is relatively isoechoic in comparison with invasive carcinoma. More than 60% of microcalcifications in comedo type intraductal carcinoma can be accurately demonstrated by ultrasound. However, the role of ultrasound in detecting symptomatic intraductal carcinoma warrants further study.

Assessing chronic disease progression using non-homogeneous exponential regression Markov models: an illustration using a selective breast cancer screening in Taiwan

Previous research on estimation of the progression of chronic disease, from the normal preclinical screen-detectable phase (PCDP) to the final clinical phase, has usually assumed constant transition rates and has rarely addressed how relevant covariates affect multi-state transitions. The present study proposes two non-homogeneous models using the Weibull distribution and piecewise exponential model, together with covariate functions of the proportional hazard form, to tackle these problems. We illustrate the models by application to a selective breast cancer screening programme. The results of the Weibull model yield estimates of scale and shape parameters for annual preclinical incidence rate as 0.0000058 (SE=0.0000019) and 2.4755 (SE=0.1153), the latter being significantly higher than 1. Annual transition rate was estimated as 0.3153 (SE=0.1385). Relative risks for the effects of late age at first pregnancy (AP) and high body mass index (BMI) on preclinical incidence rate were 1.98 and 2.59, respectively. The corresponding figures on the transition from the PCDP to clinical phase were 1.56 and 1.99, respectively. Non-homogeneous Markov models proposed in this study can be easily applied to rates of progression of chronic disease with increasing or decreasing rates with time and to model the effect of relevant covariates on multi-state transition rates.

Comparison between sonography and mammography for breast cancer diagnosis in oriental women after augmentation mammaplasty

Augmentation mammaplasty has become more popular in Taiwan. Therefore, clinical imaging is necessary to evaluate those patients who develop breast cancers. The purpose of this study was to evaluate the detection of breast diseases after augmentation mammaplasty by means of mammography and sonography. A retrospective follow-up study and analysis of diagnostic methods including mammography, sonography, physical examination, and aspiration cytology was conducted on 105 patients who underwent augmentation mammaplasty at Kaohsiung Medical University Hospital between 1989 and 2001. A total of 105 patients were identified in this study, and mean follow-up was 4 years. Two tumors from 8 cancer patients were visible on standard mammograms, and seven tumors were diagnosed as cancer by sonography. One of 15 benign breast tumors was interpreted as a suspected cancer, and 7 tumors were interpreted as normal findings on mammograms. Fourteen of 15 benign breast tumors were diagnosed correctly except for one suspicious case examined by sonography. Sonography showed the highest rate of diagnostic accuracy (91.3%) and mammograms had the lowest rate (73.9%). The accuracy rate of physical examination was 73.9%, and aspiration cytology was 90.0% accurate. This study affirms that sonography is a more useful diagnostic tool than mammography in Taiwanese women who have undergone augmentation mammaplasty.

Comparison of breast mammography, sonography and physical examination for screening women at high risk of breast cancer in taiwan

Recommended surveillance for screening breast cancer, which includes regular mammography and clinical breast examination, has long been established in Western countries. This strategy may be too costly and unnecessary for countries with low incidences of breast cancer. The purpose of the present study is to compare breast mammography, sonography and physical examination in screening female relatives of breast cancer index cases from the hospital, and their relative efficiency. A total of 935 women over 35 years old, who were relatives of breast cancer patients, were invited to an annual screening by means of a combination of mammography, sonography and physical examination on a single day. A biopsy was performed when any of the three investigations indicated a possibility of malignancy. A total of 21 breast cancers, including sixteen invasive cancers and 5 noninvasive cancers, were detected among the 935 high-risk women. Of the cancers, 18, including 16 invasive cancers and 3 noninvasive cancers, were detected by sonography. In contrast, only 11 invasive cancers were detected by mammography, and 7 by physical examination. There were only 14 cancers detected by a combination of mammography and physical examination. The 7 (33.3%) additional cancers were detected when sonography was added. The sensitivity of sonography was 90.4%, which was higher than mammography (52.4%) and physical examination (33.3%), or even a combination of these two modalities (66.7%). This indicates that sonography is a more accurate screening tool for breast cancer in the high-risk group. Although breast sonography has not yet been recommended as a routine screening tool for breast cancer in Western countries, it may be superior to mammography and physical examination for the screening of Taiwanese high-risk female relatives of breast cancer index cases. If it should also be considered as a routine adjunct screening modality for Taiwanese women with lower rates of breast cancer will need further study.

Effectiveness of breast cancer surveillance in BRCA1/2 gene mutation carriers and women with high familial risk

PURPOSE

Women with a high breast cancer risk due to a familial predisposition may choose between preventive surgery and regular surveillance. The effectiveness of surveillance in high-risk women and especially BRCA1/2 mutation carriers is unknown. We present first results from a single large family cancer clinic.

PATIENTS AND METHODS

Women with breast cancer risk over 15% were examined by physical examination every 6 months and mammography every year. Detection rates and screening parameters were calculated for the total group and separately for different age and genetic risk groups.

RESULTS

At least one examination was performed in 1,198 women: 449 moderate and 621 high-risk women and 128 BRCA1/2 mutation carriers. Within a median follow-up of 3 years, 35 breast cancers were detected (four ductal carcinoma-in-situ; 31 invasive tumors); the average detection rate was 9.7 per 1,000. Detection rates (95% confidence interval) for moderate and high-risk women and BRCA1/2 carriers were 3.3 (1.1 to 8.6), 8.4 (5.4 to 13.2), and 33 (17 to 63) per 1,000 person-years, respectively. The ratio of observed cases versus breast cancers expected in an average-risk population of comparable age was 2.7, 7.0 and 23.7 respectively. Overall, node negativity was 65%; 34% of primary tumors were less than 10 mm; sensitivity was 74%. Results with respect to tumor stage and sensitivity were less favorable in BRCA1/2 carriers and in women under the age of 40.

CONCLUSION

It is possible to identify young women at high risk for breast cancer. The number of cancers detected was significantly greater than expected in an age-matched average-risk population and related to the risk category. Overall, screening parameters were comparable to population screening data, with less favorable results in the youngest age group (< 40) and BRCA1/2 carriers.