Aggressiveness of 'true' interval invasive ductal carcinomas of the breast in postmenopausal women

MR imaging features and tumor biomarkers of screen-detected and non-screen detected breast cancers: preliminary results of a comparative study

PURPOSE

To investigate differences in clinical features, MRI findings and tumor biomarker characteristics in screen-detected (SCD) and non-screendetected (NSCD) cancers.

MATERIAL AND METHODS

A total of 62 women (mean age, 48.4 years; range, 33-68 years) with biopsy confirmed breast cancer who underwent preoperative breast MRI were retrospectively evaluated by two expert radiologists. The women were divided into two groups according to the mode of cancer detection (Group A: screen- detected, Group B: non-screen/symptomatic cancer) and clinical, histopathological, MRI characteristics and biomarker features in each group were evaluated.

RESULTS

NSCD tumors had significantly greater size (3.5 cm vs. 2.1 cm) and Ki-67 expression (68.4% vs. 41.7%) in comparison to SCD cancers. NSCD cancers were less likely to have strongly positive progesterone receptors (Pr) and more likely to have Ki-67 > 15% or positive nodal status (47.4% vs. 8.3%). Increased breast density (ACR C and D: 78.9% vs. 50%ACR A and B) and intense background parenchymal enhancement (BPE, moderate/marked: 42.1% vs. 8.3% minimal/mild) were significantly more frequent in NSCD cases.

CONCLUSION

NSCD cancers had higher prevalence of poor prognostic characteristics in comparison to SCD tumors, including larger tumor size, higher Ki-67 index, and positive nodes. Increased fibroglandular tissue and intense BPE were both strongly associated with NSCD cancers, supporting their use as potential MR biomarkers in breast cancer risk models.

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.

Interval cancers after skin cancer screening: incidence, tumour characteristics and risk factors for cutaneous melanoma

BACKGROUND

The rate of interval cancers is an established indicator for the performance of a cancer-screening programme.

METHODS

We examined the incidence, tumour characteristics and risk factors of melanoma interval cancers that occurred in participants of the SCREEN project, which was carried out 2003/2004 in Schleswig-Holstein, Germany. Data from 350 306 SCREEN participants, who had been screened negative for melanoma, were linked to data of the state cancer registry. Melanoma interval cancers were defined as melanomas diagnosed within 4-24 months after SCREEN examination. Results were compared with melanomas of the pre-SCREEN era (1999-2002), extracted from the cancer registry.

RESULTS

The overall relative incidence of melanoma interval cancers in terms of observed/expected ratio was 0.93 (95% CI: 0.82-1.05; in situ: 1.61 (1.32-1.95), invasive: 0.71 (0.60-0.84)). Compared with melanomas of the pre-SCREEN era, the interval melanomas were thinner and had a slightly greater proportion of lentigo maligna melanomas whereas nodular melanomas were less frequent.

INTERPRETATION

The results indicate a moderate performance of the SCREEN intervention with an excess of in situ melanomas. In part, the findings might be due to specifics of the SCREEN project, in particular a short-term follow-up of patients at high risk for melanoma.

A comparison of clinical-pathological characteristics between symptomatic and interval breast cancer

BACKGROUND

An association between interval breast cancers (cancer detected after a normal mammogram and before the next scheduled mammogram) and tumour aggressiveness has been postulated which may reflect their relatively poor overall prognosis. The aim of this study was to evaluate known prognostic features of screen detected breast cancers compared to interval breast cancers.

METHODS

Patients diagnosed with breast cancer between January 2010 and 2013 at a single unit of the National Breast Screening Program (NBSP) in Ireland and those between the ages of 50 and 65 diagnosed at a symptomatic breast clinic were included in the study. Patients who had not had a screening mammogram within the proceeding two years or had a previous history of breast cancer were excluded. Data were retrospectively collected on patient demographics, tumour type, grade, hormone receptor status and stage of disease at presentation.

RESULTS

There were 915 patients included in the study, with 92% (n = 844) diagnosed through the NBSP. Ductal carcinoma in-situ accounted for 19% (n = 160) of screen-detected breast cancers but only 2.8% of interval cancers (p < 0.05). The most common type of invasive cancer was invasive ductal carcinoma. Tumour grade was significantly higher in interval breast cancers (p < 0.05). Interval cancers were identified at a significantly higher stage (Stage 1 versus 2; p < 0.001) than screen-detected cancers. Interval breast cancers were less likely to be ER positive (76% versus 81%; p < 0.05) and significantly more likely to over-express HER2 (20% vs 10%, p < 0.05) than screen-detected cancers.

CONCLUSION

This study highlights the fact that interval cancers appear to have a number of adverse prognostic markers for overall breast cancer survival when compared to women with screen-detected breast cancers. Interval cancers were more likely to be invasive, of a higher grade and stage and with a greater predominance of HER2 and triple negative molecular subtypes. Therefore this heterogeneous group of tumours may be biologically more aggressive and account disproportionately to overall breast cancer mortality.

Using tumor phenotype, histological tumor distribution, and mammographic appearance to explain the survival differences between screen-detected and clinically detected breast cancers

In the era of mass screening for breast cancer with mammography, it has been noted that conventional tumor attributes and mammographic appearance are insufficient to account for the better prognosis of screen-detected tumors. Such prognostication may require additional updated pathological information regarding tumor phenotype (e.g., basal status) and histological tumor distribution (focality). We investigated this hypothesis using a Bayesian approach to analyze breast cancer data from Dalarna County, Sweden. We used data for tumors diagnosed in the Swedish Two-County Trial and early service screening period, 1977-1995, and from the mature service screening period, 1996-1998. In the early period of mammographic screening (1977-1995), the crude hazard ratio (HR) of breast cancer death for screen-detected cases compared with symptomatic ones was 0.22 (95% CI: 0.17-0.29) compared with 0.53 (95% CI: 0.34-0.76) when adjusted for conventional tumor attributes only. Using the data from the mature service screening period, 1996-1998, the HR was 0.23 (95% CI: 0.08-0.44) unadjusted and 0.71 (95% CI: 0.26-1.47) after adjustment for tumor phenotype, mammographic appearance, histological tumor distribution, and conventional tumor attributes. The area under the ROC curve (AUC) for the prediction of breast cancer deaths using these variables without the detection mode was 0.82, only slightly less than that observed when additionally including the detection mode (AUC=0.83). Using Freedman statistics, conventional tumor attributes and mammographic appearances explained 58% (95% CI: 57.5-58.6%) of the difference of breast cancer survival between the screen-detected and the clinically detected breast cancers, whereas the corresponding figure was increased to 77% (95% CI: 75.6-77.6%) when adding the two information on tumor phenotype and histological tumor distribution. The results indicated that conventional tumor attributes and mammographic appearance are not sufficient to be interim markers for explaining the survival difference between screen-detected and clinically detected cancers in the era marked by the widespread use of mammography. Additional information on tumor phenotype and histological distribution may be added as effective interim markers for explaining the benefit of the early detection of breast cancer with mammography.

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.

Differential expression of prognostic biomarkers between interval and screen-detected breast cancers: does age or family history matter?

The aim of this study was to compare tumor expression of prognostic biomarkers between interval breast cancers and screen-detected breast cancers overall, and according to age at diagnosis and familial risk. Tissue micro-arrays were constructed from 98 breast cancers (47 interval and 51 screen-detected) diagnosed in women in the Cancer Genetics Network. Arrays were immuno-stained to compare protein expression of six biomarkers including estrogen and progesterone receptor (ER/PR), Her2/neu, EGFR, cytokeratin 5/6, and Ki67. Fisher's Exact test was used to compare expression between interval and screen-detected cancers. Interval cancers were larger (P = 0.04), higher stage (P < 0.001), and more likely to have lobular histology (P = 0.01) than screen-detected cancers. Overall, interval cancers more often overexpressed EGFR (P = 0.01) and were somewhat more likely to be ER- (55% vs. 43%, P = 0.3), and triple negative (ER-/PR-/Her2-) (21 vs. 12%, P = 0.26). A greater difference in the proportion of interval versus screen-detected tumors that were ER- (53 vs. 35%; P = 0.29), PR- (35 vs. 21%; P = 0.25) and EGFR+ (17 vs. 0%; P = 0.02) was evident among women over 50. There was a trend toward differential expression among women with familial risk for PR- (P = 0.005) and triple negative status (P = 0.02). This study provides new data indicating that EGFR may be important in the etiology of interval cancer and be a possible therapeutic target. Our data also suggest that biological differences between interval and screen-detected cancers are more defined in older women. Future studies to confirm this finding and to elucidate novel markers for characterizing interval cancers may be more beneficial to this subgroup.

Copy number imbalances between screen- and symptom-detected breast cancers and impact on disease-free survival

Screening mammography results in the increased detection of indolent tumors. We hypothesized that screen- and symptom-detected tumors would show genotypic differences as copy number imbalances (CNI) that, in part, explain differences in the clinical behavior between screen- and symptom-detected breast tumors. We evaluated 850 women aged 40 and above diagnosed with stage I and II breast cancer at the University of Texas MD Anderson Cancer Center between 1985 and 2000 with information available on method of tumor detection (screen vs. symptoms). CNIs in screen- and symptom-detected tumors were identified using high-density molecular inversion probe arrays. Cox proportional modeling was used to estimate the effect of method of tumor detection on disease-free survival after adjusting for age, stage, and the CNIs. The majority of tumors were symptom detected (n = 603) compared with screen detected (n = 247). Copy number gains in chromosomes 2p, 3q, 8q, 11p, and 20q were associated with method of breast cancer detection (P < 0.00001). We estimated that 32% and 63% of the survival advantage of screen detection was accounted for by age, stage, nuclear grade, and Ki67 in women aged 50 to 70 and aged 40 to 87, respectively. In each age category, an additional 20% of the survival advantage was accounted for by CNIs associated with method of detection. Specific CNIs differ between screen- and symptom-detected tumors and explain part of the survival advantage associated with screen-detected tumors. Measurement of tumor genotype has the potential to improve discrimination between indolent and aggressive screen-detected tumors and aids patient and physician decision making about use of surgical and adjuvant treatments.

Tumor characteristics associated with mammographic detection of breast cancer in the Ontario breast screening program

BACKGROUND

Few studies have compared the prognostic value of tumor characteristics by type of breast cancer diagnosed in the interval between mammographic screenings with screen-detected breast cancers.

METHODS

We conducted a case-case study within the cohort of women (n = 431 480) in the Ontario Breast Screening Program who were aged 50 years and older and were screened between January 1, 1994, and December 31, 2002. Interval cancers, defined as breast cancers diagnosed within 24 months after a negative screening mammogram, were designated as true interval cancers (n = 288) or missed interval cancers (n = 87) if they were not identified at the time of screening but were identified in retrospect. Screen-detected breast cancers (n = 450) were selected to match interval cancers. Tumors were evaluated for stage, grade, mitotic index, histology, and expression of hormone receptors and odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by conditional logistic regression.

RESULTS

Both true and missed interval cancers were of higher stage and grade than matched screen-detected breast cancers. However, true interval cancers had a higher mitotic index (OR = 3.13, 95% CI = 1.81 to 5.42), a higher percentage of nonductal histology (OR = 1.94, 95% CI = 1.05 to 3.59), and were more likely to be both estrogen receptor-negative (OR = 2.09, 95% CI = 1.32 to 3.30) and progesterone receptor-negative (OR = 2.49, 95% CI = 1.68 to 3.70) compared with matched screen-detected tumors.

CONCLUSIONS

In this study, interval cancers were of higher stage and grade compared with screen-detected cancers. True interval cancers were more likely to have additional adverse prognostic features of estrogen and progesterone receptor negativity and nonductal morphology. The findings suggest a need for more sensitive screening modalities to detect true interval breast cancers and different approaches for early detection of fast-growing tumors.