The potential impact of breast cancer screening in Hong Kong

First report of introducing population-based breast cancer screening in Poland: experience of the 3-million population region of Lower Silesia

BACKGROUND

To achieve a reduction in breast cancer mortality in Poland a nation-wide population-based screening was introduced in 2007.

AIM

To assess the quality of breast cancer screening programme during the first round of operation in Lower Silesia-a region of over 3 million inhabitants.

METHODS

Women aged 50-69 are invited for screening, with the exception of those undergoing treatment or being followed up after treatment for breast cancer. Biennial two-view screen-film mammography is used as the standard screening test. Quality evaluation was carried out via early performance indicators. These parameters were calculated according to European Guidelines and compared with recommended levels.

RESULTS

Only 40% of women from the eligible population were screened. Among programme attendees the technical recall rate (a repeat mammogram because of technical inadequacy of the screening mammogram) was 0.27%. Further assessment rate (additional diagnostic techniques, either non-invasive or invasive, performed for medical reasons in order to clarify the nature of a perceived abnormality detected at the screening mammography) was 6.2%, while the short-term recall rate (early re-screen mammography at an interval less than the routine round length of the programme) was 2.4%. Cancer detection rate was 6.6/1000 while cancer detection rate expressed as a multiple of the expected breast cancer incidence rate was 3.8. Positive predictive values of the screening test and the further assessment were 11% and 77%, respectively.

CONCLUSION

The general assessment using early indicators reveals that diagnostic service conforms to the European standards on an acceptable or even desirable level. The only exception among these parameters is a too high short-term recall rate, which should be drastically decreased during the next rounds to improve the cost-effectiveness. The main disadvantage of the screening programme at its start is a dramatically poor coverage of the eligible population. If the invitation policy is not significantly intensified the breast cancer mortality rate will not be reduced, despite the good quality of diagnostic service.

Talking Cancer, Saving Lives: Breast Cancer Awareness Training for Health Professionals in Hong Kong

A two-day training program aimed at promoting breast cancer awareness and utilization of breast cancer screening in Hong Kong was presented to a group of breast cancer survivors and mid-level health and social services professionals ( n = 75). Using a training of trainer model, six modules were presented covering biological, psycho-social, sexual, and quality of life issues relating to breast cancer. Self-administered pre-test, post-test, and follow-up measures were used to determine participants' knowledge about breast cancer related issues and their self-perceived competence to discuss these issues professionally. The participant demographic profile was primarily female, mostly married with mean age of 38. Most of the participants attributed the causes of breast cancer to genetic, lifestyle risk, and environmental risk factors (over 60%). Their attitude, on average, was most positive regarding the difference between a support group and psychoeducational support group ( M > 8 on a 0–10 scale). Their knowledge, on average, was lowest regarding familiarity with the types and uses of alternative medicine in Hong Kong ( M < 5 on a 0–10 scale). Paired t-tests comparing pre-test to the first post-test indicated a statistically significant increase in composite scores of competence, cause recognition, and suggested frequency of breast self-exam. This training proved to be a culturally competent approach that facilitates health care providers' service provision to breast cancer survivors in Hong Kong.

Trends and patterns of breast conservation treatment in Hong Kong: 1994-2007

PURPOSE

Breast conservation treatment (BCT) was quite unpopular in Hong Kong until the early 1990s, but the trends and patterns of BCT use in the past 14 years have not been studied since. The purpose of this study was to identify the latest trends and patterns.

METHODS AND MATERIALS

All consecutive cases of female breast cancer referred to a community oncology center in Hong Kong between 1994 and 2007 were retrospectively reviewed. Of the 2,375 women with T1-2 invasive breast cancer who underwent surgery, 1,137 (48%) had T1 (</=2 cm) disease and 1,238 (52%) had T2 (>2 cm-</=5 cm) disease. Median patient age was 51 years (range, 24-95 years); 65% patients had their surgery in public hospitals.

RESULTS

Of the total patient cohort, 2,153 (91%) patients presented with palpable breast masses and only 104 (4%) with mammographically detected cancers. Overall, 721 (30%) and 1,654 (70%) patients underwent BCT and mastectomy, respectively. There was no significant increase in the BCT rates (31%, SD 5%; p = 0.804) or mammographic detection rates (5%, SD 1%; p = 0.125) in Hong Kong between 1994 and 2007. In multivariate analyses, age </=50 years (OR 2.479; p < 0.001), mammographically detected tumors (OR 1.868; p = 0.007), T1 tumors (OR 3.159; p < 0.001), surgeries in private hospitals (OR 1.288; p = 0.018), and negative nodal status (OR 1.886; p < 0.001) were independent factors predictive of a higher likelihood of a woman having BCT.

CONCLUSIONS

Our results indicate a satisfactory acceptance of BCT by patients who are young and have small tumors, node-negative disease, or surgery in private hospitals. However, the continuing unpopularity of breast screening is likely a major factor limiting the broad use of BCT.

The acceptance and feasibility of breast cancer screening in the East

Breast cancer, traditionally a disease prevalent among women in the West, has become an increasing disease burden in the East. In Hong Kong, breast cancer is the number one incident cancer in women. In Asian countries, due to the lower incidence rate, population screening is still controversial. Most screening programs are not population-based, and are either self-financed privately or partially subsidized by the government. Since the first government-subsidized screening program was set up in 1991 in Hong Kong, numerous private and government health centres for women have been set up. A dedicated private Breast Care Centre was set up at the Hong Kong Sanatorium and Hospital (HKSH) in 1999. Over an 8-year period from October 1999 to September 2006, 14,596 women were screened, of whom 11,408 were asymptomatic. This study aims to produce the first report on breast screening experience in the largest cohort of asymptomatic Chinese women in the private sector. An overall malignancy detection rate of 2.3 per 1000 screens and a recall rate of 9.2% were found. Despite culture differences and differences in breast characteristics (denser and smaller breasts), breast screening is feasible and acceptable in the East.

International variation in screening mammography interpretations in community-based programs

BACKGROUND

Variations in mammography interpretations may have important clinical and economic implications. To evaluate international variability in mammography interpretation, we analyzed published reports from community-based screening programs from around the world.

METHODS

A total of 32 publications were identified in MEDLINE that fit the study inclusion criteria. Data abstracted from the publications included features of the population screened, examination technique, and clinical outcomes, including the percentage of mammograms judged to be abnormal, positive predictive value of an abnormal mammogram (PPV(A)), positive predictive value of a biopsy performed (PPV(B)), and percentages of breast cancer patients with ductal carcinoma in situ (DCIS) and minimal disease (DCIS and/or tumor size < or =10 mm). North American screening programs were compared with those from other countries using meta-regression analysis. All statistical tests were two-sided.

RESULTS

Wide ranges were noted for the percentage of mammograms judged to be abnormal (1.2%-15.0%), for PPV(A) (3.4%-48.7%), for PPV(B) (5.0%-85.2%), for percentage diagnosed with DCIS (4.3%-68.1%), and for percentage diagnosed with minimal disease (14.0%-80.6%). The percentage of mammograms judged to be abnormal were 2-4 percentage points higher in North American screening programs than they were in programs from other countries, after adjusting for covariates such as percentage of women who were less than 50 years of age and calendar year in which the mammogram was performed. The percentage of mammograms judged to be abnormal had a negative association with PPV(A) and PPV(B) (both P<.001) and a positive association with the frequency of DCIS cases diagnosed (P =.008) and the number of DCIS cases diagnosed per 1000 screens (P =.024); no consistent relationship was observed with the proportion of breast cancer diagnoses reported as having minimal disease or the number of minimal disease cases diagnosed per 1000 screens.

CONCLUSION

North American screening programs appear to interpret a higher percentage of mammograms as abnormal than programs from other countries without evident benefit in the yield of cancers detected per 1000 screens, although an increase in DCIS detection was noted.

Will screening mammography in the East do more harm than good?

OBJECTIVES

We sought to systematically review the evidence for population-based mammography as applied to a Chinese population.

METHODS

Primary reports for meta-analysis were identified by a search of MEDLINE and the Cochrane Library. Outcome measures included breast cancer-related mortality, the number needed to be screened to prevent 1 death, and the positive predictive value of mammography.

RESULTS

Pooled relative risk for breast cancer-related death in the screened group was 0.80 (95% confidence interval = 0.71, 0.90). Applied to Hong Kong, this figure translates into a number needed to screen of 1 302 healthy women screened annually for 10 years to prevent 1 death.

CONCLUSIONS

Evidence is insufficient to justify population-based breast cancer screening by mammography for women in Hong Kong and other Asian populations with low breast cancer prevalence.

Ductal carcinoma in situ of the breast in Singapore: recent trends and clinical implications

BACKGROUND

Breast ductal carcinoma in-situ (DCIS) is increasingly being diagnosed as a result of screening mammography and better pathological recognition. With this and the rising breast cancer incidence in Singapore, DCIS is poised to become a bigger part of surgical practice. Principles of screening, diagnosis and management of DCIS have also been rapidly evolving. Against this background, a clinicopathological audit of recent cases of DCIS in our centre was performed.

METHODS

Thirty-eight cases of DCIS diagnosed in the period 1997-2000 were retrospectively analysed. Histological examination and immunohistochemical studies for oestrogen and progesterone receptor expression were performed.

RESULTS

In the present study, DCIS was most common in the group of patients who were <50 years (58%) as compared to an American series' where the corresponding group were > or =60 years (36%). Compared to a previous local study a decade ago, the present series showed that: (i) DCIS constituted a higher proportion of all breast cancers (6.4% vs 3.7%); (ii) a larger proportion of patients had disease detected by mammography (47% vs 10%); (iii) conservative breast excision was the only definitive surgery in 39% of cases (vs approximately 30%); and (iv) the mean size of lesions is smaller (13.5 mm vs 24.4 mm). Histologically, 26% of tumours were high grade, 71% had necrosis while 32% were oestrogen receptor (ER) and progesterone receptor (PR) negative. High grade tumours were associated with the presence of necrosis (P = 0.018), ER negativity (P = 0.015) and PR negativity (P = 0.001).

CONCLUSIONS

This study reveals interesting trends of DCIS in Singapore. The sizeable proportion of hormone receptor-negative tumours may have implications for the hormonal adjuvant therapy of DCIS.

Genetic imbalances in pT2 breast cancers of southern Chinese women

While much information has been reported on the genetic alterations in breast cancers of Caucasians, little is known about the Oriental populations where breast cancers currently rank the second most common neoplasm. As a first step toward understanding the underlying genetics changes in this population, we used comparative genomic hybridization (CGH) to the genome-wide analysis of forty pT2 tumors from patients of a racially homogenous population in southern China. A complex pattern of genetic alterations emerged with the commonest chromosomal gains identified on 1q (58%), 8q (55%), 11q13 (25%), 16p (28%), 17q (53%) and 20q (35%), and frequent losses on 8p (38%), 11q (28%), 13q (30%) and 18q (25%). When breast cancers with and without lymph-node metastasis were compared, a higher copy gain of 10p was identified in the node-positive group (P=.036). An overall increase in the average number of genetic aberrations was also identified in the late onset group (>45 years)(P=.042) with a higher incidence of genetic losses noted (P=.035). In particular, losses on 16q were detected in 30% of the late onset patients but none in the early onsets (P=0.049). In this study, we have illustrated the pattern of genetic changes in breast tumors of southern Chinese females. While frequent 1q, 8q, 17q and 20q gains, and common 8p and 13q deletions detected were consistent to those aberrations reported from the Caucasian populations, the difference in genetic changes associated in lymph-node metastasis and age of onset identified should provide the basis for additional investigations into the underlying tumorigenesis in the Oriental population.