Are international differences in breast cancer survival between Australia and the UK present amongst both screen-detected women and non-screen-detected women? survival estimates for women diagnosed in West Midlands and New South Wales 1997-2006

Method of primary breast cancer detection and the disease-free interval, adjusting for lead time

BACKGROUND

Little is known about the impact of screen-detected breast cancer compared with clinically detected breast cancer on the disease-free interval (ie, free from locoregional recurrences, distant metastasis, contralateral breast cancer). Moreover, it is thought that most studies overestimate the beneficial effect of screening, as they do not adjust for lead time. We investigated the association between method of breast cancer detection and disease-free interval, taking lead time into account.

METHODS

Women aged 50-76 years, diagnosed with breast cancer between 2005 and 2008 were selected from the Netherlands Cancer Registry. Women diagnosed in 2005 were divided into screen-detected and clinically detected cancer and had a follow-up of 10 years (2005 cohort). Women diagnosed in 2006-2008 were divided into screen-detected, interval, and nonscreen-related cancer and had a follow-up of 5 years (2006-2008 cohort). A previously published method was used to adjust for lead time. Analyses were repeated correcting for confounding variables instead of lead time.

RESULTS

The 2005 cohort included 6215 women. Women with screen-detected cancer had an improved disease-free interval compared with women with clinically detected cancer (hazard ratio [HR] = 0.77, 95% confidence interval [CI] = 0.68 to 0.87). The 2006-2008 cohort included 15 176 women. Women with screen-detected or interval cancer had an improved disease-free interval compared with women with nonscreen-related cancer (HR = 0.76, 95% CI = 0.66 to 0.88; HR = 0.88, 95% CI = 0.78 to 0.99, respectively). Correcting for confounders instead of lead time did not change associations.

CONCLUSION

Women with screen-detected cancer had an improved disease-free interval compared with women with a nonscreen-related or clinically detected cancer, after correction for lead time.

Evaluation of a population-based breast cancer screening in North China

BACKGROUND

Despite mammography-based screening for breast cancer has been conducted in many countries, there are still little data on participation and diagnostic yield in population-based breast cancer screening in China.

METHODS

We enrolled 151,973 eligible women from four cities in Hebei Province within the period 2013-2021 and followed up until December 31, 2021. Participants aged 40-74 who assessed as high risk were invited to undergo breast ultrasound and mammography examination. Overall and group-specific participation rates were calculated. Multivariable analyses were used to estimate the factors associated with participation rates. The diagnostic yield of both screening and no screening groups was calculated. We further analyzed the stage distribution and molecular subtype of breast cancer cases by different modes of cancer detection.

RESULTS

A total of 42,547 participants were evaluated to be high risk of breast cancer. Among them, 23,009 subjects undertook screening services, with participation rate of 54.08%. Multivariable logistic regression model showed that aged 45-64, high education level, postmenopausal, current smoking, alcohol consumption, family history of breast cancer, and benign breast disease were associated with increased participation of screening. After median follow-up of 3.79 years, there were 456 breast cancer diagnoses of which 65 were screen-detected breast cancers (SBCs), 27 were interval breast cancers (IBCs), 68 were no screening cancers, and 296 were cancers detected outside the screening program. Among them, 92 participants in the screening group (0.40%) and 364 in the non-screening group (0.28%) had breast cancer detected, which resulted in an odds ratio of 1.42 (95% CI 1.13-1.78; P = 0.003). We observed a higher detection rate of breast cancer in the screening group, with ORs of 2.42 (95% CI 1.72-3.41) for early stage (stages 0-I) and 2.12 (95% CI 1.26-3.54) for luminal A subtype. SBCs had higher proportion of early stage (71.93%) and luminal A subtype (47.22%) than other groups.

CONCLUSIONS

The significant differences in breast cancer diagnosis between the screening and non-screening group imply an urgent need for increased breast cancer awareness and early detection in China.

Survival after breast cancer according to participation in organised or opportunistic screening and deprivation

BACKGROUND

Many studies have investigated the survival of women by comparing those who participated in organised screening with those who did not. However, among those who do not participate in organised screening, some women undergo opportunistic screening, but these women remain difficult to identify, particularly in France. Therefore, the aim of this study was to identify opportunistic screening, and then to study survival after breast cancer separately according to participation in organised, opportunistic or no screening, and taking into account sociodemographic inequalities.

METHODS

The study population was identified from 3 French cancer registries, whose data was crossed with the screening coordination centers and the National Health Data System to identify the different type of screening. The European Deprivation Index was used to define the level of deprivation. We estimated net survival using the Pohar-Perme method.

RESULTS

The 5-year net survival probabilities were higher for women who attended organised screening (97.0 %) than for women with opportunistic screening (94.1 %) or non-attenders (78.1 %). According to the level of deprivation, a significant difference was observed between the groups of women screened by organised and opportunistic screening, compared to the non-attenders.

CONCLUSION

The identification of opportunistic screening is an important element in identifying women who do not screening. It enables to us to see that women who do not attend any screening have a much higher loss-of-opportunity in terms of survival than those who participate in organised or opportunistic screening, and even more so in the most deprived areas.

Adverse health effects after breast cancer up to 14 years after diagnosis

BACKGROUND

The number of breast cancer survivors increases, but information about long-term adverse health effects in breast cancer survivors is sparse. We aimed to get an overview of the health effects for which survivors visit their general practitioner up to 14 years after diagnosis.

METHODS

We retrieved data on 11,671 women diagnosed with breast cancer in 2000-2016 and 23,242 age and sex matched controls from the PSCCR-Breast Cancer, a database containing data about cancer diagnosis, treatment and primary healthcare. We built Cox regression models for 685 health effects, with time until the health effect as the outcome and survivor/control and cancer treatment as predictors. Models were built separately for four age groups (aged 18/44, 45/59, 60/74 and 75/89) and two follow-up periods (1/4 and 5/14 years after diagnosis).

RESULTS

229 health effects occurred statistically significantly more often in survivors than in controls (p < 0.05). Health effects varied by age, time since diagnosis and treatment, but coughing, respiratory and urinary infections, fatigue, sleep problems, osteoporosis and lymphedema were statistically significantly increased in breast cancer survivors. Osteoporosis and chest symptoms were associated with hormone therapy; respiratory and skin infections with chemotherapy and lymphedema and skin infections with axillary dissection.

CONCLUSIONS

Breast cancer survivors may experience numerous adverse health effects up to 14 years after diagnosis. Insight in individual risks may assist healthcare professionals in managing patient expectations and improve monitoring, detection and treatment of adverse health effects.

Impact of deprivation on breast cancer survival among women eligible for mammographic screening in the West Midlands (UK) and New South Wales (Australia): Women diagnosed 1997-2006

Women diagnosed with breast cancer in the UK display marked differences in survival between categories defined by socio-economic deprivation. Timeliness of diagnosis is one of the possible explanations for these patterns. Women whose cancer is screen-detected are more likely to be diagnosed at an earlier stage. We examined deprivation and screening-specific survival in order to evaluate the role of early diagnosis upon deprivation-specific survival differences in the West Midlands (UK) and New South Wales (Australia). We estimated net survival for women aged 50-65 years at diagnosis and whom had been continuously eligible for screening from the age of 50. Records for 5,628 women in West Midlands (98.5% of those eligible, mean age at diagnosis 53.7 years) and 6,396 women in New South Wales (99.9% of those eligible, mean age at diagnosis 53.8 years). In New South Wales, survival was similar amongst affluent and deprived women, regardless of whether their cancer was screen-detected or not. In the West Midlands, there were large and persistent differences in survival between affluent and deprived women. Deprivation differences were similar between the screen-detected and non-screen detected groups. These differences are unlikely to be solely explained by artefact, or by patient or tumour factors. Further investigations into the timeliness and appropriateness of the treatments received by women with breast cancer across the social spectrum in the UK are warranted.