Interval Cancers in Understanding Screening Outcomes

Interval breast cancers are not detected at routine screening and are diagnosed in the interval between screening examinations. A variety of factors contribute to interval cancers, including patient and tumor characteristics as well as the screening technique and frequency. The interval cancer rate is an important metric by which the effectiveness of screening may be assessed and may serve as a surrogate for mortality benefit.

Radiological features of screening-detected and interval breast cancers and subsequent survival in Eastern Finnish women

Interval breast cancers are diagnosed between scheduled screenings and differ in many respects from screening-detected cancers. Studies comparing the survival of patients with interval and screening-detected cancers have reported differing results. The aim of this study was to investigate the radiological and histopathological features and growth rates of screening-detected and interval breast cancers and subsequent survival. This retrospective study included 942 female patients aged 50-69 years with breast cancers treated and followed-up at Kuopio University Hospital between January 2010 and December 2016. The screening-detected and interval cancers were classified as true, minimal-signs, missed, or occult. The radiological features were assessed on mammograms by one of two specialist breast radiologists with over 15 years of experience. A χ2 test was used to examine the association between radiological and pathological variables; an unpaired t test was used to compare the growth rates of missed and minimal-signs cancers; and the Kaplan-Meier estimator was used to examine survival after screening-detected and interval cancers. Sixty occult cancers were excluded, so a total of 882 women (mean age 60.4 ± 5.5 years) were included, in whom 581 had screening-detected cancers and 301 interval cancers. Disease-specific survival, overall survival and disease-free survival were all worse after interval cancer than after screening-detected cancer (p < 0.001), with a mean follow-up period of 8.2 years. There were no statistically significant differences in survival between the subgroups of screening-detected or interval cancers. Missed interval cancers had faster growth rates (0.47% ± 0.77%/day) than missed screening-detected cancers (0.21% ± 0.11%/day). Most cancers (77.2%) occurred in low-density breasts (< 25%). The most common lesion types were masses (73.9%) and calcifications (13.4%), whereas distortions (1.8%) and asymmetries (1.7%) were the least common. Survival was worse after interval cancers than after screening-detected cancers, attributed to their more-aggressive histopathological characteristics, more nodal and distant metastases, and faster growth rates.

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.

Severity and risk factors of interval breast cancer in Queensland, Australia: a population-based study

BACKGROUND

Interval breast cancers (BC) are those diagnosed within 24 months of a negative mammogram. This study estimates the odds of being diagnosed with high-severity BC among screen-detected, interval, and other symptom-detected BC (no screening history within 2 years); and explores factors associated with being diagnosed with interval BC.

METHODS

Telephone interviews and self-administered questionnaires were conducted among women (n = 3,326) diagnosed with BC in 2010-2013 in Queensland. Respondents were categorised into screen-detected, interval, and other symptom-detected BCs. Data were analysed using logistic regressions with multiple imputation.

RESULTS

Compared with screen-detected BC, interval BC had higher odds of late-stage (OR = 3.50, 2.9-4.3), high-grade (OR = 2.36, 1.9-2.9) and triple-negative cancers (OR = 2.55, 1.9-3.5). Compared with other symptom-detected BC, interval BC had lower odds of late stage (OR = 0.75, 0.6-0.9), but higher odds of triple-negative cancers (OR = 1.68, 1.2-2.3). Among women who had a negative mammogram (n = 2,145), 69.8% were diagnosed at their next mammogram, while 30.2% were diagnosed with an interval cancer. Those with an interval cancer were more likely to have healthy weight (OR = 1.37, 1.1-1.7), received hormone replacement therapy (2-10 years: OR = 1.33, 1.0-1.7; > 10 years: OR = 1.55, 1.1-2.2), conducted monthly breast self-examinations (BSE) (OR = 1.66, 1.2-2.3) and had previous mammogram in a public facility (OR = 1.52, 1.2-2.0).

CONCLUSION

These results highlight the benefits of screening even among those with an interval cancer. Women-conducted BSE were more likely to have interval BC which may reflect their increased ability to notice symptoms between screening intervals.

Interval breast cancer is associated with interferon immune response

BACKGROUND

The aggressive nature of breast cancers detected between planned mammographic screens, so-called interval cancers, remains elusive. Here, we aim to characterise underlying molecular features of interval cancer.

METHODS

From 672 patients with invasive breast cancer, we analysed gene expression differences between 90 'true' interval cancer cases (i.e. women with low-dense breasts defined as per cent mammographic density <25%) and 310 screen-detected tumours while accounting for PAM50 subtypes and thus overall tumour aggressiveness. We computed an interval cancer gene expression profile (IC-Gx) in a total of 2270 breast tumours (regardless of interval cancer status) and tested for association with expression-based immune subtypes in breast cancer. In addition, we investigated the contribution of inherited and somatic genetic variants in distinct features of interval cancer.

RESULTS

We identified 8331 genes nominally associated with interval cancer (P-value < 0.05, fold-change > 1.5). Gene set enrichment analysis showed immune-related pathways as key processes altered in interval cancer. Our IC-Gx, based on 47 genes with the strongest associations (false discovery rate < 0.05), was found to be associated mainly with immune subtypes involving interferon response. We isolated an interaction network of interval cancer and interferon genes for which a significant load of somatic and germline variants in class I interferon genes was observed.

CONCLUSION

We identified novel molecular features of interval breast cancer highlighting interferon pathways as a potential target for prevention or treatment.

Combining method of detection and 70-gene signature for enhanced prognostication of breast cancer

PURPOSE

Studies have shown that screen detection by national screening programs is independently associated with better prognosis of breast cancer. The aim of this study is to evaluate the association between tumor biology according to the 70-gene signature (70-GS) and survival of patients with screen-detected and interval breast cancers.

METHODS

All Dutch breast cancer patients enrolled in the MINDACT trial (EORTC-10041/BIG3-04) accrued 2007-2011, who participated in the national screening program (biennial screening, ages 50-75) were included (n = 1102). Distant Metastasis-Free Interval (DMFI) was evaluated according to the 70-GS for patients with screen-detected (n = 754) and interval cancers (n = 348).

RESULTS

Patients with screen-detected cancers had 8-year DMFI rates of 98.2% for 70-GS ultralow-, 94.6% for low-, and 93.8% for high-risk tumors (p = 0.4). For interval cancers, there was a significantly lower 8-year DMFI rate for patients with 70-GS high-risk tumors (85.2%) compared to low- (92.2%) and ultralow-risk tumors (97.4%, p = 0.0023). Among patients with 70-GS high-risk tumors, a significant difference in 8-year DMFI rate was observed between interval (85.2%, n = 166) versus screen-detected cancers (93.8%, n = 238; p = 0.002) with a HR of 2.3 (95%CI 1.2-4.4, p = 0.010) adjusted for clinical-pathological characteristics and adjuvant systemic treatment.

CONCLUSION

Among patients with 70-GS high-risk tumors, a significant difference in DMFI was observed between screen-detected and interval cancers, suggesting that method of detection is an additional prognostic factor in this subgroup and should be taken into account when deciding on adjuvant treatment strategies.

Differences between screen-detected and interval breast cancers among BRCA mutation carriers

BACKGROUND

BRCA mutation carriers have an elevated lifetime breast cancer risk and remain at risk for interval cancer development. We sought to compare BRCA mutation carriers with screen-detected versus interval breast cancers.

METHODS

Women with a known BRCA mutation prior to a breast cancer diagnosis were identified. Clinical and pathologic factors, and imaging within 18 months of diagnosis were compared among screen-detected versus interval cancers. Interval cancers were those detected by physical exam among women undergoing regular screening.

RESULTS

Of 124 breast cancers, 92 were screen and 22 clinically detected, of which 11 were interval cancers among regular screeners, and 10 were incidentally found on prophylactic mastectomy. Women with interval cancers were younger, had lower body mass indexes, and were more likely to be Black than those with screen-detected cancers (p < 0.05). Interval cancers were all invasive, larger, more likely to be node positive, and more likely to require axillary lymph node dissection and chemotherapy (p < 0.05). No significant differences were seen by BRCA mutation, mammographic density, MRI background parenchymal enhancement, tumor grade, or receptor status between cohorts. Women screened with both mammogram and MRI had significantly lower proportions of interval cancers compared to women screened with only mammogram or MRI alone (p < 0.05).

CONCLUSIONS

Interval breast cancers among BRCA mutation carriers have worse clinicopathologic features than screen-detected tumors, and require more-aggressive medical and surgical therapy. Imaging with mammogram and MRI is associated with lower interval cancer development and should be utilized among this high-risk population.

Breast Cancer Screening Program in Lithuania: Interval Cancers and Program Sensitivity After 7 Years of Mammography Screening

OBJECTIVE

Analysis of interval cancers is critical in determining the sensitivity of screening and represents an objective measure of the quality of mammography screening program (MSP).

METHODS

Period analyzed: from 2006 to 2012. The rate of screen-detected, interval cancers and program sensitivity were measured. A comparison of screen-detected and interval cancers was performed.

RESULTS

During the period of the study, 429 473 women were screened and 1297 were found to have cancer. The overall screen-detected cancer rate was 30.2 per 10 000 women screened. Four hundred thirty-one case of interval cancers have occurred during the period of the study. The interval cancer ratio (ICR) was 0.25. Overall sensitivity of MSP amounted to 75.1%. Slightly lower sensitivity was found among the youngest age-group, especially for those with lobular cancers. Interval cancers were bigger in size, more often with metastases in lymph nodes, than screen-detected cancers, but these differences were not statistically significant.

CONCLUSIONS

Overall program sensitivity in Lithuania is about 75%, ICR is 0.25, and these parameters are comparable to other European countries.

Tumour characteristics of bilateral screen-detected cancers and bilateral interval cancers in women participating at biennial screening mammography

BACKGROUND

Unilateral interval breast cancers show less favourable prognostic features than unilateral screen-detected cancers, but data on tumour characteristics of bilateral interval cancers in a systematically screened population are sparse. Therefore, we compared tumour characteristics of bilateral interval cancers with those of bilateral screen-detected cancers.

METHODS

We included all 468,720 screening mammograms of women who underwent biennial screening mammography in the South of the Netherlands between January 2005 and January 2015. We collected breast imaging reports, biopsy results and surgical reports of all recalled women and of all women who presented with interval breast cancer. In women with synchronous bilateral breast cancer, the tumour with the highest tumour stage was defined as the index cancer. For comparison of data between both groups Fisher exact test and Chi-square test were used.

RESULTS

Synchronous bilateral cancer was diagnosed in 2.2% of screen-detected cancers (64/2947) and in 3.2% of interval cancers (24/753) (P = 0.1). Index tumours of bilateral screen-detected cancers and interval cancers showed similar characteristics, except for a larger proportion of T-stage 2 or worse (T2+) cancers among interval cancers (16/24 (66.7%) versus 23/58 (39.7%) (P = 0.03). Index cancers, compared to contralateral cancers, were less frequently stage T1 in both bilateral screen-detected cancers and bilateral interval cancers (35/64 (60.3%) versus 40/64 (88.9%) (P = 0.001) and 8/24 (33.3%) versus 18/24 (85.7%) (P < 0.001), respectively). In bilateral screen-detected cancers, contralateral cancers were more often stage 1a-c (P < 0.001) compared to index cancers. In bilateral index cancers, index cancers were more often of the lobular subtype (P < 0.001).

CONCLUSION

Index cancers of bilateral screen-detected cancers and bilateral interval cancers show significant differences in tumour size, whereas nodal status, receptor status and final surgical treatment are comparable. In bilateral screen-detected cancer, index cancers had a significantly higher tumour stage. In bilateral screen-detected cancer, index cancers were more often the ductal invasive subtype compared to contralateral cancers.

Differences in Breast Cancer Characteristics by Mammography Screening Participation or Non-Participation

BACKGROUND

The goal of the German Mammography Screening Program (MSP) is to enable the early detection and less intensive treatment of breast cancer. We compared tumor characteristics and prognostic markers in breast cancers that were detected by screening in the MSP, in the interval after a negative screening, or among non-participants in screening.

METHODS

This retrospective series includes all of the 1531 cases of invasive and in situ breast cancer (DCIS, ductal carcinoma in situ) that were newly diagnosed in two certified breast care centers in Münster in the period 2006-2012 among women in the MSP target population. Complete information on the tumor characteristics, tumor biology, and primary surgical treatment were available for all cases. The mode of cancer detection was determined from the state cancer registry of North Rhine-Westphalia. Due to the retrospective design of this case series, there was no randomized allocation.

RESULTS

The 874 cases of breast cancer among MSP participants (714 detected by screening, 160 in the interval after a negative screen) and the 657 cases among non-participants arose in women of similar age (mean, 60.2 versus 59.3 years). MSP participants with breast cancer had DCIS more commonly than non-participants did (23% versus 13%); invasive carcinomas were smaller (74% versus 55% in the T1 stage), less commonly node-positive (25% versus 31%), less commonly high-grade (19% versus 27%), and less commonly triple-negative (7% versus 12%); MSP participants received neoadjuvant treatment less frequently (2% versus 8%) and more frequently underwent breast-conserving surgery (75% versus 62%). They less commonly had a guideline-based indication for adjuvant chemotherapy (46% versus 52%).

CONCLUSION

MSP participants with invasive breast cancer can generally be treated with less intensive surgical and systemic therapy than non-participants, even if interval cancers are also taken into account. Future studies should also investigate quality of life after a diagnosis of invasive carcinoma in screening participants.

PAM50 and Risk of Recurrence Scores for Interval Breast Cancers

Breast cancers detected after a negative breast screening examination and prior to the next screening are referred to as interval cancers. These cancers generally have poor clinical characteristics compared with screen-detected cancers, but associations between interval cancer and genomic cancer characteristics are not well understood. Mammographically screened women diagnosed with primary invasive breast cancer from 1993 to 2013 (n = 370) were identified by linking the Carolina Breast Cancer Study and the Carolina Mammography Registry. Among women with a registry-identified screening mammogram 0 to 24 months before diagnosis, cancers were classified as screen-detected (N = 165) or interval-detected (N = 205). Using logistic regression, we examined the association of mode of detection with cancer characteristics (clinical, IHC, and genomic), overall, and in analyses stratified on mammographic density and race. Interval cancer was associated with large tumors [>2 cm; OR, 2.3; 95% confidence interval (CI), 1.5-3.7], positive nodal status (OR, 1.8; 95% CI, 1.1-2.8), and triple-negative subtype (OR, 2.5; 95% CI, 1.1-5.5). Interval cancers were more likely to have non-Luminal A subtype (OR, 2.9; 95% CI, 1.5-5.7), whereas screen-detected cancers tended to be more indolent (96% had low risk of recurrence genomic scores; 71% were PAM50 Luminal A). When stratifying by mammographic density and race, associations between interval detection and poor prognostic features were similar by race and density status. Strong associations between interval cancers and poor-prognosis genomic features (non-Luminal A subtype and high risk of recurrence score) suggest that aggressive tumor biology is an important contributor to interval cancer rates. Cancer Prev Res; 11(6); 327-36. ©2018 AACR.

Impact of Detection Method and Age on Survival Outcomes in Triple-Negative Breast Cancer: A Population-Based Cohort Analysis

BACKGROUND

Most investigations have compared triple-negative breast cancer (TNBC) to non-TNBC to elucidate clinical or epidemiologic differences between subtypes. We examined a contemporary cohort of patients with primary TNBC by detection and age at diagnosis within a population-based breast screening program to examine survival outcomes.

PATIENTS AND METHODS

All women with a diagnosis of primary TNBC between January 1, 2005, and December 31, 2012, in Nova Scotia, Canada, were included. Clinicopathologic and detection variables were abstracted from the Nova Scotia Breast Screening Program. Patient charts were abstracted for adjuvant therapies and survival outcomes, supplemented by provincial vital statistical data.

RESULTS

A total of 412 patients comprised the study population, with almost half aged over 60 years (46.3%) and 30.2% having screen-detected disease. There were no significant differences in prognostic variables between age groups. Younger patients were more likely to receive adjuvant chemotherapy (96.3% ≤ 49 years vs. 31.2% ≥ 70 years), but there were no differences in disease-free or breast cancer-specific survival between the age groups. For those with disease recurrence, median time to recurrence and death was shorter for younger patients (17 vs. 26 months, 16 vs. 33 months respectively; age 40-49 vs. 70+). Those with screen-detected disease had better disease-free, breast cancer-specific, and overall survival outcomes.

CONCLUSION

Detection method may play a role in TNBC survival outcomes, thus supporting novel screening strategies for TNBC. Shorter time to survival events in the younger patient groups suggests that TNBC is a clinically heterogeneous disease despite similarities in prognostic factors across age.

Aggressive primary treatments with favourable 5-year survival for screen-interval breast cancers

Background

To assess the impact of the participation in screening programme according to the mode of detection on the early diagnosis, treatment, and specific survival outcomes in women with breast cancer.

Methods

Women diagnosed with invasive breast cancer in Poitou-Charentes region (France) between 2008 and 2009 were classified into three groups, using data linkage of cancer registry, vital statistics and French organized screening programme: the screening programme (SP), interval cancer (IC), and non-screening programme detected cancer (NSP) groups. Specific survival rates were analysed using the Kaplan–Meier method and Cox proportional hazard models.

Results

Among 1613 patients, 65.7% (n = 1059) participated in a screening programme. The interval cancer rate was 17.1% (n = 181). Tumours in the IC group were diagnosed at a more advanced stage, i.e. with further regional lymph node metastasis or local spread, than those in the SP group (p < 0.001), but with significantly fewer metastases at diagnosis than in the NSP group (p < 0.001). ICs underwent more aggressive primary treatments than the two other groups, with 28% of radical mastectomy and 67% undergoing chemotherapy. The five-year survival rate for IC group were 92.0% (95% CI, 89.9–94.0%).

Conclusions

Interval cancers had more aggressive features than screen-detected cancers but were diagnosed at a less advanced stage compared to non-screen detected cancers. Despite having cancers missed by the screening programme, women who participate in the screening process seem to benefit from early treatment. These results must be confirmed with long-term follow-up.

Errors in Mammography Cannot be Solved Through Technology Alone

Mammography has been the frontline screening tool for breast cancer for decades. However, high error rates in the form of false negatives (FNs) and false positives (FPs) have persisted despite technological improvements. Radiologists still miss between 10% and 30% of cancers while 80% of woman recalled for additional views have normal outcomes, with 40% of biopsied lesions being benign. Research show that the majority of cancers missed is actually visible and looked at, but either go unnoticed or are deemed to be benign. Causal agents for these errors include human related characteristics resulting in contributory search, perception and decision-making behaviours. Technical, patient and lesion factors are also important relating to positioning, compression, patient size, breast density and presence of breast implants as well as the nature and subtype of the cancer itself, where features such as architectural distortion and triple-negative cancers remain challenging to detect on screening. A better understanding of these causal agents as well as the adoption of technological and educational interventions, which audits reader performance and provide immediate perceptual feedback, should help. This paper reviews the current status of our knowledge around error rates in mammography and explores the factors impacting it. It also presents potential solutions for maximizing diagnostic efficacy thus benefiting the millions of women who undergo this procedure each year.

Incidence and tumour characteristics of bilateral and unilateral interval breast cancers at screening mammography

BACKGROUND

Detected by screening mammography, bilateral breast cancer has a different pathological profile compared to unilateral breast cancer. We investigated the incidence of bilateral interval breast cancers and compared their characteristics with those of unilateral interval breast cancers.

METHODS

We included all 468,720 screening mammograms of women who underwent biennial screening mammography in the South of the Netherlands between January 2005 and January 2015. We collected breast imaging reports, biopsy results and surgical reports of all referred women and of all women who presented with interval breast cancer. The tumour with the highest tumour stage (index cancer) was used for comparison with unilateral interval cancers.

RESULTS

A total of 753 interval cancers were detected, of which 24 (3.2%) were bilateral. Among the invasive interval cancers, bilateral cancers more frequently showed a lobular histology than unilateral cancers (37.5% (9/24) vs. 16.1% (111/691), P = .01). There is a trend towards a larger proportion of bilateral than unilateral interval cancers graded 1 (45.8% (11/24) vs. 27.8% (192/691), P = .08). There were no other statistically significant differences in tumour characteristics. Also, the proportion of interval cancers showing significant mammographic abnormalities at the latest screen was comparable for unilateral and bilateral interval cancers (23.0% vs. 25.0%, P = .9).

DISCUSSION

Bilateral interval cancers comprise a small proportion of all interval cancers. Except of a higher proportion of invasive lobular cancers and a more favourable histological grade of invasive cancers, tumour characteristics are comparable for bilateral and unilateral interval breast cancers.

Prognostic impact of interval breast cancer detection in women with pT1a N0M0 breast cancer with HER2-positive status: Results from a multicentre population-based cancer registry study

BACKGROUND

Although human epidermal growth factor receptor 2 (HER2) overexpression is associated with poor prognosis, patients (pts) with pT1a N0M0 breast cancers (BCs) have an excellent outcome across all subtypes. Interval cancers (ICs) have poorer survival than screen-detected (SD) tumours, and an association has been reported between ICs and HER2 overexpression. We aimed to determine, in a general population of pT1a N0M0 BCs with known screening status, whether HER2-positive ICs have a poorer outcome than HER2-positive SD cancers.

METHODS

We evaluated all incident pT1a N0M0 BCs (n = 874) collected in the Emilia-Romagna region (Italy) from 2003 to 2009 and diagnosed in women aged 50-69. Pts unexposed to screening, with unknown HER2 status and/or treated with adjuvant trastuzumab were excluded from analysis.

RESULTS

Sixty-one percent of the BCs were SD, whereas 19% were ICs. BCs with high histologic grade, hormone receptor-negative or HER2-positive status (odds ratio=1.7; 95% confidence interval [CI]: 1.1-2.7) were more likely ICs. Median follow-up was 115 months. The 10-year invasive disease-free survival (iDFS) for HER2-positive ICs was lower than that for HER2-positive SD cancers: 75.0% (95% CI: 55.5%-94.5%) versus 93.8% (95% CI: 86.5%-100%). An interaction between ICs and HER2-positive status was found for poorer iDFS after adjusting for prognostic variables (HR = 5.3; 95% CI: 1.6-16.7).

CONCLUSIONS

IC detection may identify pts with HER2-positive pT1a N0M0 tumours in whom the rate of recurrence justifies consideration for conventional, anti-HER2, adjuvant treatment.

Interval Breast Cancer Versus Screen-Detected Cancer: Comparison of Clinicopathologic Characteristics in a Single-Center Analysis

BACKGROUND

The introduction of breast screening programs has raised the problem of interval breast cancers (IBC). The aims of this study were to analyze the impact of IBC on the screening program, to compare IBC and screen-detected cancers (SDC), and to identify possible predictors of mortality.

PATIENTS AND METHODS

Patients with breast cancer diagnosed during the regional breast screening program between January 2008 and December 2013 at a single center in Italy were included. Demographic, preoperative, and postoperative data were prospectively collected and retrospectively analyzed.

RESULTS

Five hundred thirty-four patients were enrolled; 106 women (19.9%) had IBC and 428 women (80.1%) SDC. IBC presented more aggressive features compared to SDC, such as tumor invasiveness (95% vs. 85%; P = .005), tumor size (≥ pT2 37% vs. 21%; P = .001), grade (G3 39% vs. 17%; P < .001), and St Gallen molecular subtype (triple negative 22% vs. 7%; P < .001), resulting in higher distant recurrence rate (8% vs. 2%; P = .009) and worse overall and disease-free survival (P = .03 and P = .001, respectively). Cox multivariate regression analysis identified St Gallen molecular subtype as the only predictor of mortality in patients with breast cancer (P = .03).

CONCLUSION

IBC accounted for one-fifth of all breast cancers diagnosed in women who followed the regional screening program. Furthermore, IBC appeared to have more aggressive features compared to SDC, leading to worse survival. These worse survivals depended on St Gallen molecular subtype.

Opportunities for improving triple-negative breast cancer outcomes: results of a population-based study

Triple‐negative breast cancer (TNBC) is associated with a poor prognosis. Surgery, radiotherapy, chemotherapy, and referral for genetic counseling are the standard of care. We assessed TNBC prevalence, management, and outcome using data from the population‐based Geneva cancer registry. 2591 women had a first invasive stage I‐III breast cancer diagnosed between 2003 and 2011. We compared TNBC to other breast cancers (OBC) by χ²‐test and logistic regression. Kaplan–Meier survival curves, up to 31‐12‐2014, were compared using log‐rank test. TNBC risk of mortality overall (OS) and for breast cancer (BCSS) was evaluated through Cox models. Linkage with the Oncogenetics and Cancer Prevention Unit (OCPU) database of the Geneva University Hospitals provided genetic counseling information. TNBC patients (n = 192, 7.4%) were younger, more often born in Africa or Central‐South America than OBC, had larger and more advanced tumors. 18% of TNBC patients did not receive chemotherapy. Thirty‐one (17%) TNBC women consulted the OCPU, 39% among those aged <40 years. Ten‐year survival was lower in TNBC than OBC (72% vs. 82% for BCSS; P < 0.001; 80% vs. 91% for OS; P < 0.001). The mortality risks remained significant after adjustment for other prognostic variables. The strongest determinants of mortality were age, place of birth, and lymph node status. A substantial proportion of TNBC patients in Geneva did not receive optimal care. Over 60% of eligible women did not receive genetic counseling and 18% did not receive chemotherapy. To improve TNBC prognosis, comprehensive care as recommended by standard guidelines should be offered to all patients.

Growing concern following compression mammography

A patient without clinical symptoms had a mammogram in October 2008. The procedure caused intense persistent pain, swelling and development of a haematoma following mediolateral left breast compression. Three months later, a 9×11 cm mass developed within the same region. Core biopsies showed a necrotizing high-grade ductal carcinoma, with a high mitotic index. Owing to its extensive size, the patient began chemotherapy followed by trastuzumab and later radiotherapy to obtain clear margins for a subsequent mastectomy. The mastectomy in October 2009 revealed an inflammatory carcinoma, with 2 of 3 nodes infiltrated by the tumour. The stage IIIC tumour, oestrogen and progesterone receptor negative, was highly HER2 positive. A recurrence led to further chemotherapy in February 2011. In July 2011, another recurrence was removed from the mastectomy scar. She died of progressive disease in 2012. In this article, we discuss the potential influence of compression on the natural history of the tumour.

Expected 10-year treatment cost of breast cancer detected within and outside a public screening program in Norway

BACKGROUND

The shift towards earlier stages of disease advancement at diagnosis when introducing mammography screening is expected to affect the treatment costs of breast cancer.

MATERIALS AND METHODS

We collected data on hospital resource use in Norway following a breast cancer diagnosis for the period 1 January, 2008 through 31 December, 2009 for women aged 50-69 years, diagnosed with breast cancer during the period 1 January, 1999 through 31 December, 2009. We estimated treatment costs using a function that included the probability of being at risk for receiving treatment, estimated by means of the Cox proportional hazard model.

RESULTS

In total, 16,045 patients were included for the analyses among which 10.5 % died during the study period. The mean 10-year per-person treatment cost was €31,940 (95 % CI €31,030-32,880), and lower for cancers detected within the public screening program (€30,730) than for those detected elsewhere (€36,230). For ductal carcinoma in situ (DCIS) and cancers in stages I thru IV, treatment costs were €15,740, €23,570, €46,550, €55,230 and €60,430, respectively. Interval cancers occurring within the screening program were generally more resource demanding than both cancers detected at screening or elsewhere.

CONCLUSIONS

Ten-year treatment costs increased by increasing stage at diagnosis. Patients whose cancer was detected within the public screening program had lower treatment costs than those detected elsewhere. Interval cancers had higher costs than others.

Performance indicators evaluation of the population-based breast cancer screening programme in Northern Portugal using the European Guidelines

OBJECTIVE

To evaluate the first 10 years of operation of the population-based breast cancer screening programme implemented in the Northern Region of Portugal, using selected recommended standard performance indicators.

METHODS

Data from women aged 50-69 screened with two-view mammography, biennially, in the period 2000-2009, were included. Main performance indicators were compared with the recommended levels of the European Guidelines.

RESULTS

A total of 202,039 screening examinations were performed, 71,731 (35.5%) in the initial screening and 130,308 (64.5%) in the subsequent screening. Coverage rate by examination reached 74.3% of the target population, in the last period evaluated. Recall rates were 8.1% and 2.4% and cancer detection rates were 4.4/1000 and 2.9/1000 respectively, for initial and subsequent screenings. The breast cancer detection rate, expressed as a multiple of the background expected incidence was 3.1 in initial screen and 2.2 in subsequent screen. The incidence of invasive interval cancers met the desirable recommended levels both the first and second years since last screening examination, in the initial and subsequent screenings. Invasive tumours <15mm were 50.4% and 53.8% of the invasive cancers detected in initial and subsequent screenings. Less favourable size, grading and biomarkers expression were found in interval cancers compared to screen-detected cancers.

CONCLUSIONS

Breast cancer screening programme in the Northern Region of Portugal was well accepted by the population. Most of the performance indicators were consistent with the desirable levels of the European Guidelines, which indicate an effective screening programme. Future research should verify the consistency of some of these results by using updated information from a larger population.

Triple-negative breast cancer: what is known about it?

Triple-negative breast cancer (TNBC) is considered a rare diagnosis. This malignancy targets a specific population of women and has risk factors differing from those of other breast cancers. TNBC exhibits distinct pathologic features that result in aggressive metastasis and poor prognosis. Pathologically, TNBC cancer cells are characterized by negative receptors for progesterone and estrogen and by the lack of over-expression of human epidermal growth factor receptor 2, which limits chemotherapeutic treatment options for women with TNBC. Nurses can assist in early detection by offering patient education about the little known risk factors for TNBC. Psychosocial issues can overwhelm patients diagnosed with breast cancer. This article provides suggestions for nurses as they guide women who are experiencing an atypical breast cancer diagnosis with an uncertain prognosis and limited treatment options.

Multi-level factors influence the implementation and use of complex innovations in cancer care: a multiple case study of synoptic reporting

BACKGROUND

The implementation of innovations (i.e., new tools and practices) in healthcare organizations remains a significant challenge. The objective of this study was to examine the key interpersonal, organizational, and system level factors that influenced the implementation and use of synoptic reporting tools in three specific areas of cancer care.

METHODS

Using case study methodology, we studied three cases in Nova Scotia, Canada, wherein synoptic reporting tools were implemented within clinical departments/programs. Synoptic reporting tools capture and present information about a medical or surgical procedure in a structured, checklist-like format and typically report only items critical for understanding the disease and subsequent impacts on patient care. Data were collected through semi-structured interviews with key informants, document analysis, nonparticipant observation, and tool use/examination. Analysis involved production of case histories, in-depth analysis of each case, and a cross-case analysis. Numerous techniques were used during the research design, data collection, and data analysis stages to increase the rigour of this study.

RESULTS

The analysis revealed five common factors that were particularly influential to implementation and use of synoptic reporting tools across the three cases: stakeholder involvement, managing the change process (e.g., building demand, communication, training and support), champions and respected colleagues, administrative and managerial support, and innovation attributes (e.g., complexity, compatibility with interests and values). The direction of influence (facilitating or impeding) of each of these factors differed across and within cases.

CONCLUSIONS

The findings demonstrate the importance of a multi-level contextual analysis to gaining both breadth and depth to our understanding of innovation implementation and use in health care. They also provide new insights into several important issues under-reported in the literature on moving innovations into healthcare practice, including the role of middle managers in implementation efforts and the importance of attending to the interpersonal aspects of implementation.

Evaluation of the interval cancer rate and its determinants on the Girona Health Region's early breast cancer detection program

BACKGROUND

The main aim of this study is to estimate the rate of false negative and true IC on the Program for the Early Detection of Breast Cancer (PEDBC) run by the Girona Health Region (GHR) and compare the clinicopathological characteristics of these tumors with those detected within the same program.

METHODS

A retrospective cohort study including all women participating on the Girona PEDBC between 2000 and 2006, with negative mammography screening. The IC included are those detected between the first and second round of screening and between the second and third round.

RESULTS

We identified a total of 43 IC, representing an incidence rate of 0.70 cases per 1,000 screened women. Of the 43 probable IC, we were able to classify a total of 22 (51.2%) cases. Of these 22 cases, 54.5% were classified as true interval tumors, 13.6% false negatives, 18.2% occult tumors and the remaining 13.6% minimal sign.We found significant differences in some clinicopathological characteristics of the IC comparing with the tumors detected within the program during the same period.

CONCLUSIONS

The IC rate for the PEDBC is within the expected parameters, with a high proportion of cases of true interval cancers (54.5%) and a low proportion of false negatives (13.6%). The results show that the proportional incidence of IC is within the limits set by European Guidelines. Furthermore, it has been confirmed that IC display more aggressive clinicopathological characteristics than screening breast cancers.

Local recurrence in women with stage I breast cancer: declining rates over time in a large, population-based cohort

PURPOSE

To evaluate whether local recurrence (LR) risk has changed over time among women with stage I breast cancer treated with breast-conserving therapy.

METHODS AND MATERIALS

Subjects were 5974 women aged ≥50 years diagnosis with pT1N0 breast cancer from 1989 to 2006, treated with breast-conserving surgery and radiation therapy. Clinicopathologic characteristics, treatment, and LR outcomes were compared among 4 cohorts stratified by year of diagnosis: 1989 to 1993 (n=1077), 1994 to 1998 (n=1633), 1999 to 2002 (n=1622), and 2003 to 2006 (n=1642). Multivariable analysis was performed, with year of diagnosis as a continuous variable.

RESULTS

Median follow-up time was 8.6 years. Among patients diagnosed in 1989 to 1993, 1994 to 1998, 1999 to 2002, and 2003 to 2006, the proportions of grade 1 tumors increased (16% vs 29% vs 40% vs 39%, respectively, P<.001). Surgical margin clearance rates increased from 82% to 93% to 95% and 88%, respectively (P<.001). Over time, the proportions of unknown estrogen receptor (ER) status decreased (29% vs 10% vs 1.2% vs 0.5%, respectively, P<.001), whereas ER-positive tumors increased (56% vs 77% vs 86% vs 86%, respectively, P<.001). Hormone therapy use increased (23% vs 23% vs 62% vs 73%, respectively, P<.001), and chemotherapy use increased (2% vs 5% vs 10% vs 13%, respectively, P<.001). The 5-year cumulative incidence rates of LR over the 4 time periods were 2.8% vs 1.7% vs 0.9% vs 0.8%, respectively (Gray's test, P<.001). On competing risk multivariable analysis, year of diagnosis was significantly associated with decreased LR (hazard ratio, 0.92 per year, P=.0003). Relative to grade 1 histology, grades 2, 3, and unknown were associated with increased LR. Hormone therapy use was associated with reduced LR.

CONCLUSION

Significant changes in the multimodality management of stage I breast cancer have occurred over the past 2 decades. More favorable-risk tumors were diagnosed, and margin clearance and systemic therapy use increased. These changes contributed to the observed declining LR rates among patients treated with breast-conserving therapy.

The incidence and 10-year survival of interval breast cancers in Wales

AIM

To evaluate the number of interval cancers (IC) within one screening cycle and the overall 10-year survival of IC, including its four main classifications, and compare that to screen-detected cancers (SDC).

MATERIALS AND METHODS

Within Breast Test Wales (BTW), all SDC between the years 1998 and 2001 were included. IC that occurred between 1998 and 2003 that had undergone screening between the years 1998 and 2001 were also included. These IC were classified into true interval (TI), false negative (FN), occult cancer (OCC), and unclassified cancer (UCC). BTW received notification of all deaths of women that had undergone screening; thus, the 10-year all-cause survival rate was calculated from the date of diagnosis and death.

RESULTS

During the study period, 199,082 women attended screening. Of these, 1020 (0.51%) women had SDC and 692 (0.38%) women developed IC. Of the 692 IC, 391 (57.8%) were TI, 120 (17.7%) were FN, 68 (10%) were OCC, and 98 (14.5%) were UCC; 15 (2.2%) were not classified. After a 10-year follow-up period, the 10-year survival rate (all-cause) for SDC was 81.6%, overall for all of IC was 72.4% (OR = 1.67, p < 0.001), TI was 77.5% (OR = 1.00, p = 0.99), FN was 55% (OR = 2.36, p < 0.001), OCC was 54.4% (OR = 3.17, p < 0.001), and UCC was 87.8% (OR = 0.61, p = 0.19).

CONCLUSIONS

The overall 10-year survival of IC was significantly different to SDC. However, within this, the prognosis of TI was similar to SDC, whereas FN and OCC had significantly worse long-term survival. Further research is required to identify the underlying cause of poor survival of FN and OCC.

Tumor phenotype and breast density in distinct categories of interval cancer: results of population-based mammography screening in Spain

INTRODUCTION

Interval cancers are tumors arising after a negative screening episode and before the next screening invitation. They can be classified into true interval cancers, false-negatives, minimal-sign cancers, and occult tumors based on mammographic findings in screening and diagnostic mammograms. This study aimed to describe tumor-related characteristics and the association of breast density and tumor phenotype within four interval cancer categories.

METHODS

We included 2,245 invasive tumors (1,297 screening-detected and 948 interval cancers) diagnosed from 2000 to 2009 among 645,764 women aged 45 to 69 who underwent biennial screening in Spain. Interval cancers were classified by a semi-informed retrospective review into true interval cancers (n = 455), false-negatives (n = 224), minimal-sign (n = 166), and occult tumors (n = 103). Breast density was evaluated using Boyd's scale and was conflated into: <25%; 25 to 50%; 50 to 75%; >75%. Tumor-related information was obtained from cancer registries and clinical records. Tumor phenotype was defined as follows: luminal A: ER+/HER2- or PR+/HER2-; luminal B: ER+/HER2+ or PR+/HER2+; HER2: ER-/PR-/HER2+; triple-negative: ER-/PR-/HER2-. The association of tumor phenotype and breast density was assessed using a multinomial logistic regression model. Adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. All statistical tests were two-sided.

RESULTS

Forty-eight percent of interval cancers were true interval cancers and 23.6% false-negatives. True interval cancers were associated with HER2 and triple-negative phenotypes (OR = 1.91 (95% CI:1.22-2.96), OR = 2.07 (95% CI:1.42-3.01), respectively) and extremely dense breasts (>75%) (OR = 1.67 (95% CI:1.08-2.56)). However, among true interval cancers a higher proportion of triple-negative tumors was observed in predominantly fatty breasts (<25%) than in denser breasts (28.7%, 21.4%, 11.3% and 14.3%, respectively; <0.001). False-negatives and occult tumors had similar phenotypic characteristics to screening-detected cancers, extreme breast density being strongly associated with occult tumors (OR = 6.23 (95% CI:2.65-14.66)). Minimal-sign cancers were biologically close to true interval cancers but showed no association with breast density.

CONCLUSIONS

Our findings revealed that both the distribution of tumor phenotype and breast density play specific and independent roles in each category of interval cancer. Further research is needed to understand the biological basis of the overrepresentation of triple-negative phenotype among predominantly fatty breasts in true interval cancers.

Gene expression profiling in true interval breast cancer reveals overactivation of the mTOR signaling pathway

BACKGROUND

The development and progression of true interval breast cancers (tumors that truly appear after a negative screening mammogram) is known to be different from screen-detected cancers. However, the worse clinical behavior of true interval cancers is not fully understood from a biologic basis. We described the differential patterns of gene expression through microarray analysis in true interval and screen-detected cancers.

METHODS

An unsupervised exploratory gene expression profile analysis was performed on 10 samples (true interval cancers = 5; screen-detected cancers = 5) using Affymetrix Human Gene 1.0ST arrays and interpreted by Ingenuity Pathway Analysis. Differential expression of selected genes was confirmed in a validation series of 91 tumors (n = 12; n = 79) by immunohistochemistry and in 24 tumors (n = 8; n = 16) by reverse transcription quantitative PCR (RT-qPCR), in true interval and screen-detected cancers, respectively.

RESULTS

Exploratory gene expression analysis identified 1,060 differentially expressed genes (unadjusted P < 0.05) between study groups. On the basis of biologic implications, four genes were further validated: ceruloplasmin (CP) and ribosomal protein S6 kinase, 70 kDa, polypeptide 2 (RPS6KB2), both upregulated in true interval cancers; and phosphatase and tensin homolog (PTEN) and transforming growth factor beta receptor III (TGFBR3), downregulated in true interval cancers. Their differential expression was confirmed by RT-qPCR and immunohistochemistry, consistent with mTOR pathway overexpression in true interval cancers.

CONCLUSIONS

True interval and screen-detected cancers show differential expression profile both at gene and protein levels. The mTOR signaling is significantly upregulated in true interval cancers, suggesting this pathway may mediate their aggressiveness.

IMPACT

Linking epidemiologic factors and mTOR activation may be the basis for future personalized screening strategies in women at risk of true interval cancers.

Prognosis in women with interval breast cancer: population based observational cohort study

OBJECTIVE

To compare the prognosis in women with interval breast cancer (cancer detected after a normal screening mammogram and before the next scheduled mammogram) with breast cancer detected among women not yet invited to mammography screening (non-screened).

DESIGN

Population based observational study.

SETTING

Norwegian breast cancer screening programme, implemented in different counties from 1996 to 2005.

PARTICIPANTS

7116 women with a diagnosis of breast cancer at age 50 to 72 years; 1816 had interval breast cancer and 5300 had a diagnosis of breast cancer but had not yet been invited to screening.

MAIN OUTCOME MEASURES

Characteristics of the breast tumours, and survival of the women using Kaplan Meier curves and multivariable Cox proportional hazard models.

RESULTS

Although interval cancers on average were slightly larger than the cancers in women not invited to screening, the histological type or status of axillary lymph nodes did not differ noticeably between the two groups. Among interval cancers, there were no appreciable trends in size, nodal status, grade, or hormone receptor positivity associated with time since the last normal mammogram as a marker of growth rate. After 10 years of follow-up, the survival rates were 79.1% (95% confidence interval 75.4% to 82.3%) among women with interval cancers and 76.8% (75.3% to 78.2%) among women in the non-screened cancer group (hazard ratio 0.98, 95% confidence interval 0.84 to 1.15; P=0.53). Analyses stratified by time since last normal mammogram, age at diagnosis, or screening round showed similar results.

CONCLUSION

The prognosis of women with interval breast cancers was the same as that of women with breast cancers diagnosed without mammography screening.

Exploring the interpersonal-, organization-, and system-level factors that influence the implementation and use of an innovation-synoptic reporting-in cancer care

Background

The dominant method of reporting findings from diagnostic and surgical procedures is the narrative report. In cancer care, this report inconsistently provides the information required to understand the cancer and make informed patient care decisions. Another method of reporting, the synoptic report, captures specific data items in a structured manner and contains only items critical for patient care. Research demonstrates that synoptic reports vastly improve the quality of reporting. However, synoptic reporting represents a complex innovation in cancer care, with implementation and use requiring fundamental shifts in physician behaviour and practice, and support from the organization and larger system. The objective of this study is to examine the key interpersonal, organizational, and system-level factors that influence the implementation and use of synoptic reporting in cancer care.

Methods

This study involves three initiatives in Nova Scotia, Canada, that have implemented synoptic reporting within their departments/programs. Case study methodology will be used to study these initiatives (the cases) in-depth, explore which factors were barriers or facilitators of implementation and use, examine relationships amongst factors, and uncover which factors appear to be similar and distinct across cases. The cases were selected as they converge and differ with respect to factors that are likely to influence the implementation and use of an innovation in practice. Data will be collected through in-depth interviews, document analysis, observation of training sessions, and examination/use of the synoptic reporting tools. An audit will be performed to determine/quantify use. Analysis will involve production of a case record/history for each case, in-depth analysis of each case, and cross-case analysis, where findings will be compared and contrasted across cases to develop theoretically informed, generalisable knowledge that can be applied to other settings/contexts. Ethical approval was granted for this study.

Discussion

This study will contribute to our knowledge base on the multi-level factors, and the relationships amongst factors in specific contexts, that influence implementation and use of innovations such as synoptic reporting in healthcare. Such knowledge is critical to improving our understanding of implementation processes in clinical settings, and to helping researchers, clinicians, and managers/administrators develop and implement ways to more effectively integrate innovations into routine clinical care.

Could screening participation bias symptom interpretation? An interview study on women's interpretations of and responses to cancer symptoms between mammography screening rounds

OBJECTIVES

To explore how women with negative mammography screening results, but who were later diagnosed with interval breast cancer, reacted when they observed breast symptoms that could indicate malignancy in-between screening rounds.

DESIGN

Semistructured individual interviews with women who have been diagnosed with breast cancer during mammography screening intervals.

SETTING

Two breast diagnostic units covering two counties in Norway.

PARTICIPANTS

26 women diagnosed with interval breast cancer.

RESULTS

Women with a screening negative result react in two ways when experiencing a possible symptom of breast cancer. Among 24 women with a self-detected palpable lesion, 14 sought medical advice immediately. Their argument was to dispose of potential cancer as soon as possible. Ten women delayed seeking medical advice, explaining their delay as a result of practical difficulties such as holidays, uncertainty about the symptom, and previous experiences of healthcare services' ability to handle diffuse symptoms. Also, a recent negative mammography scan led some women to assume that the palpable lesion was benign and wait for the next screening round.

CONCLUSIONS

Participating in mammography screening may contribute to a postponed reaction to breast cancer symptoms, although most women acted rapidly when detecting a palpable breast lesion. Furthermore, screening participation does not necessarily increase awareness of breast cancer symptoms.

Elevated PCNA+ tumor-associated macrophages in breast cancer are associated with early recurrence and non-Caucasian ethnicity

African American and Hispanic women develop more triple negative breast cancer at younger ages than Caucasian women. The frequently observed association between race and socioeconomic status (SES) has confounded our understanding of the outcomes disparities seen in these groups. Given the association between inflammatory cells and high-grade, triple negative tumors, we sought to investigate whether differences in the presence of these cells varies by race. We evaluated breast tumor specimens for the presence PCNA+ tumor-associated macrophages (TAMs) in consecutive cases from a county hospital serving primarily un- or under-insured patients. All patients in this cohort had elevated PCNA + TAM levels. Higher PCNA + TAM counts were associated with hormone receptor (HR) negative tumors and non-Caucasian ethnicity. Hispanic women specifically had significantly higher PCNA + TAM counts than Caucasian patients and shorter disease-free survival. These findings implicate immune function in the development of aggressive breast cancer and suggest a possible link between SES and the inflammatory response.