Growth pattern of ductal carcinoma in situ (DCIS): a retrospective analysis based on mammographic findings

Mammographic surveillance after breast cancer

Early detection of local recurrence has been shown to improve survival. What is unclear is how frequently mammography should be performed, how long surveillance should continue and how the answers to these questions vary with tumour pathology, patients age, and surgery type. Many of these questions are not directly answerable from the current literature. While some of these questions will be answered by the Mammo-50 study, evidence from local recurrence rates, tumour biology, and the lead time of mammography can be used to guide policy. Young age is the strongest predictor of local recurrence and given the short lead time of screening in women under 50, these women require annual mammography. Women over 50 with HER-2 positive and triple negative breast cancer have higher rates of local recurrence after breast conserving surgery than women with luminal cancers. Women with HER-2 positive and triple negative breast cancer also have a higher rate of recurrence in years 1-3 post surgery. Annual mammography in year 1-4 would appear justified. Women over 50 with luminal cancers have low rates of local recurrence and no early peak. Recurrence growth will be low due to tumour biology and hormone therapy. Biennial mammography after year 2 would seem appropriate. Women over 50 following mastectomy have no early peak in contralateral cancers so the frequency should be determined by the lead time of screening. This would suggest 2 yearly mammography for women aged 50-60 while 3 yearly mammography may suffice for women over 60.

Tailored radiation dose according to margin width for patients with ductal carcinoma in situ after breast-conserving surgery

A 2 mm resection margin is considered adequate for ductal carcinoma in situ (DCIS). We assessed the effectiveness of a tailored radiation dose for margins < 2 mm and the appropriate margin width for high-risk DCIS. We retrospectively evaluated 137 patients who received adjuvant radiotherapy after breast-conserving surgery for DCIS between 2013 and 2019. The patients were divided into three- positive, close (< 2 mm), and negative (≥ 2 mm) margin groups. Radiation dose to the tumor bed in equivalent dose in 2 Gy fractions were a median of 66.25 Gy, 61.81 Gy, and 59.75 Gy for positive, close, and negative margin groups, respectively. During a median follow-up of 58 months, the crude rates of local recurrence were 15.0%, 6.7%, and 4.6% in the positive, close, and negative margin groups, respectively. The positive margin group had a significantly lower 5-year local recurrence-free survival (LRFS) rate compared to the close and negative margin groups in propensity-weighted log-rank analysis (84.82%, 93.27%, and 93.20%, respectively; p = 0.008). The difference in 5-year LRFS between patients with the high- and non-high-grade tumors decreased as the margin width increased (80.4% vs. 100.0% for margin ≥ 2 mm, p < 0.001; 92.3% vs. 100.0% for margin ≥ 6 mm, p = 0.123). With the radiation dose tailored for margin widths, positive margins were associated with poorer local control than negative margins, whereas close margins were not. Widely clear margins (≥ 2 mm) were related to favorable local control for high-grade DCIS.

Spatial genomics maps the structure, nature and evolution of cancer clones

Genome sequencing of cancers often reveals mosaics of different subclones present in the same tumour1-3. Although these are believed to arise according to the principles of somatic evolution, the exact spatial growth patterns and underlying mechanisms remain elusive4,5. Here, to address this need, we developed a workflow that generates detailed quantitative maps of genetic subclone composition across whole-tumour sections. These provide the basis for studying clonal growth patterns, and the histological characteristics, microanatomy and microenvironmental composition of each clone. The approach rests on whole-genome sequencing, followed by highly multiplexed base-specific in situ sequencing, single-cell resolved transcriptomics and dedicated algorithms to link these layers. Applying the base-specific in situ sequencing workflow to eight tissue sections from two multifocal primary breast cancers revealed intricate subclonal growth patterns that were validated by microdissection. In a case of ductal carcinoma in situ, polyclonal neoplastic expansions occurred at the macroscopic scale but segregated within microanatomical structures. Across the stages of ductal carcinoma in situ, invasive cancer and lymph node metastasis, subclone territories are shown to exhibit distinct transcriptional and histological features and cellular microenvironments. These results provide examples of the benefits afforded by spatial genomics for deciphering the mechanisms underlying cancer evolution and microenvironmental ecology.

Unresected screen-detected ductal carcinoma in situ: Outcomes of 311 women in the Forget-Me-Not 2 study

BACKGROUND AND AIM

The natural history of ductal carcinoma in situ (DCIS) is poorly understood. The aim of this cohort study was to determine the outcomes of women who had no surgery for screen-detected DCIS in the 6 months following diagnosis.

METHODS

English breast screening databases were retrospectively searched for women diagnosed with DCIS without invasive cancer at screening and who had no record of surgery within 6 months of diagnosis. These were cross-referenced with cancer registry data. Details of the potentially eligible women were sent to the relevant breast screening units for verification and for completion of data forms detailing clinical, radiological and pathological findings, non-surgical treatment and subsequent clinical course.

RESULTS

Data for 311 eligible women (median age 62 years) were available. 60 women developed invasive cancer, 56 ipsilateral and 4 contralateral. Ipsilateral invasion risk increased approximately linearly with time for at least 10 years. The 10-year cumulative risk of ipsilateral invasion was 9% (95% CI 4-21%), 39% (24-58%) and 36% (24-50%) for low, intermediate and high grade DCIS respectively and was higher in younger women, in those with larger DCIS lesions and in those with microinvasion. Most invasive cancers that developed were grade 2 or 3.

CONCLUSION

The findings suggest that active surveillance may be a reasonable alternative to surgery in patients with low grade DCIS but that women with intermediate or high grade disease should continue to be offered surgery. This highlights the importance of reproducible grading of DCIS to ensure patients receive appropriate treatment.

Section Discrepancy and Diagnostic Performance of Breast Lesions in Two-dimensional Ultrasound by Dynamic Videos versus Static Images

Background: Benign or malignant breast lesions with typical ultrasonic characteristics could be easily and correctly diagnosed with two-dimensional ultrasound (2D US). However, diagnosis of atypical lesions remains a challenge. Most atypical lesions have different ultrasonographic features with probe direction variation. Thus, the interpretation of ultrasonographic features based on static images empirically collected by sonographers might be inaccurate. We aimed to investigate the section discrepancy and diagnostic performance of breast lesions in 2D US by dynamic videos versus static images.Methods: Static images and dynamic videos based on two perpendicular planes of 468 breast lesions were collected and evaluated. The Breast Imaging and Reporting Data System (BI-RADS&#x00AE;) US lexicon was used. Category 3 was used as the cut-off point, and section discrepancy was defined as two perpendicular planes showing different BI-RADS categories (3 versus 4A, 4B, 4C, and 5).Results: This retrospective study included 315 benign and 153 malignant lesions. There were 53 and 50 lesions with section discrepancy during static and dynamic observations, respectively. The proportion of benign lesions with section discrepancy was significantly higher than that of malignant lesions (P &#x003C; 0.05) either in dynamic or static observation, and the contingency coefficient was 0.2 between section discrepancy and histopathology. Duct changes were more clearly depicted in dynamic videos than in static images (P &#x003C; 0.05) both in malignant and benign lesions. Calcification and architectural distortion were more sensitively detected by dynamic videos than with static images (P &#x003C; 0.05) in malignant lesions. The interpretation of &#x201C;margin&#x201D; significantly differed in benign lesions between static images and dynamic videos (P &#x003C; 0.05). The areas under the curve of static image-horizontal, static image-sagittal, dynamic video-horizontal, and dynamic video-sagittal were 0.807, 0.820, 0.837, and 0.846, respectively. The specificities of dynamic videos were higher than those of static images (P &#x003C; 0.05).Conclusion: Breast lesions have section discrepancy in 2D US. Observations based on dynamic videos could more accurately reflect lesion features and increase the specificity of US in the differentiation of atypical breast lesions.

A Multiscale Agent-Based Model of Ductal Carcinoma In Situ

OBJECTIVE

we present a multiscale agent-based model of Ductal Carcinoma in Situ (DCIS) in order to gain a detailed understanding of the cell-scale population dynamics, phenotypic distributions, and the associated interplay of important molecular signaling pathways that are involved in DCIS ductal invasion into the duct cavity (a process we refer to as duct advance rate here).

METHODS

DCIS is modeled mathematically through a hybridized discrete cell-scale model and a continuum molecular scale model, which are explicitly linked through a bidirectional feedback mechanism.

RESULTS

we find that duct advance rates occur in two distinct phases, characterized by an early exponential population expansion, followed by a long-term steady linear phase of population expansion, a result that is consistent with other modeling work. We further found that the rates were influenced most strongly by endocrine and paracrine signaling intensity, as well as by the effects of cell density induced quiescence within the DCIS population.

CONCLUSION

our model analysis identified a complex interplay between phenotypic diversity that may provide a tumor adaptation mechanism to overcome proliferation limiting conditions, allowing for dynamic shifts in phenotypic populations in response to variation in molecular signaling intensity. Further, sensitivity analysis determined DCIS axial advance rates and calcification rates were most sensitive to cell cycle time variation.

SIGNIFICANCE

this model may serve as a useful tool to study the cell-scale dynamics involved in DCIS initiation and intraductal invasion, and may provide insights into promising areas of future experimental research.

Reliability of preoperative breast biopsies showing ductal carcinoma in situ and implications for non-operative treatment: a cohort study

PURPOSE

The future of non-operative management of DCIS relies on distinguishing lesions requiring treatment from those needing only active surveillance. More accurate preoperative staging and grading of DCIS would be helpful. We identified determinants of upstaging preoperative breast biopsies showing ductal carcinoma in situ (DCIS) to invasive breast cancer (IBC), or of upgrading them to higher-grade DCIS, following examination of the surgically excised specimen.

METHODS

We studied all women with DCIS at preoperative biopsy in a large specialist cancer centre during 2000-2014. Information from clinical records, mammography, and pathology specimens from both preoperative biopsy and excised specimen were abstracted. Women suspected of having IBC during biopsy were excluded.

RESULTS

Among 606 preoperative biopsies showing DCIS, 15.0% (95% confidence interval 12.3-18.1) were upstaged to IBC and a further 14.6% (11.3-18.4) upgraded to higher-grade DCIS. The risk of upstaging increased with presence of a palpable lump (21.1% vs 13.0%, pdifference = 0.04), while the risk of upgrading increased with presence of necrosis on biopsy (33.0% vs 9.5%, pdifference < 0.001) and with use of 14G core-needle rather than 9G vacuum-assisted biopsy (22.8% vs 7.0%, pdifference < 0.001). Larger mammographic size increased the risk of both upgrading (pheterogeneity = 0.01) and upstaging (pheterogeneity = 0.004).

CONCLUSIONS

The risk of upstaging of DCIS in preoperative biopsies is lower than previously estimated and justifies conducting randomized clinical trials testing the safety of active surveillance for lower grade DCIS. Selection of women with low grade DCIS for such trials, or for active surveillance, may be improved by consideration of the additional factors identified in this study.

Growth Dynamics of Mammographic Calcifications: Differentiating Ductal Carcinoma in Situ from Benign Breast Disease

Background Most ductal carcinoma in situ (DCIS) lesions are first detected on screening mammograms as calcifications. However, false-positive biopsy rates for calcifications range from 30% to 87%. Improved methods to differentiate benign from malignant calcifications are thus needed. Purpose To quantify the growth rates of DCIS and benign breast disease that manifest as mammographic calcifications. Materials and Methods All calcifications (n = 2359) for which a stereotactic biopsy was performed from 2008 through 2015 at Duke University Medical Center were retrospectively identified. Mammograms from all cases of DCIS (n = 404) were reviewed for calcifications that were visible on mammograms taken at least 6 months before biopsy. Women with at least one prior mammogram with visible calcifications were age- and race-matched 1:2 to women with a benign breast biopsy and calcifications visible on prior mammograms. The long axis of the calcifications was measured on all mammograms. Multivariable adjusted linear mixed-effects models estimated the association of calcification growth rates with patholo findings. Hierarchical clustering accounted for matching benign and DCIS groups. Results A total of 74 DCIS calcifications and 148 benign calcifications were included for final analysis. The median patient age was 62 years (interquartile range, 51-71 years). No significant difference in breast density (P > .05) or number of available mammograms (P > .05) was detected between groups. Calcifications associated with DCIS were larger than those associated with benign breast disease at biopsy (median, 10 mm vs 6 mm, respectively; P < .001). After adjustment, the relative annual increase in the long-axis length of DCIS calcifications was greater than that of benign breast calcifications (96% [95% confidence interval: 72%, 224%] vs 68% [95% confidence interval: 56%, 80%] per year, respectively; P < .001). Conclusion Ductal carcinoma in situ calcifications are more extensive at diagnosis and grow faster in extent than those associated with benign breast disease. The rate of calcification change may help to discriminate benign from malignant calcifications. © RSNA, 2019 Online supplemental material is available for this article.

Progress Towards Computational 3-D Multicellular Systems Biology

Tumors cannot be understood in isolation from their microenvironment. Tumor and stromal cells change phenotype based upon biochemical and biophysical inputs from their surroundings, even as they interact with and remodel the microenvironment. Cancer should be investigated as an adaptive, multicellular system in a dynamical microenvironment. Computational modeling offers the potential to detangle this complex system, but the modeling platform must ideally account for tumor heterogeneity, substrate and signaling factor biotransport, cell and tissue biophysics, tissue and vascular remodeling, microvascular and interstitial flow, and links between all these sub-systems. Such a platform should leverage high-throughput experimental data, while using open data standards for reproducibility. In this chapter, we review advances by our groups in these key areas, particularly in advanced models of tissue mechanics and interstitial flow, open source simulation software, high-throughput phenotypic screening, and multicellular data standards. In the future, we expect a transformation of computational cancer biology from individual groups modeling isolated parts of cancer, to coalitions of groups combining compatible tools to simulate the 3-D multicellular systems biology of cancer tissues.

Breast segmentectomy with rotation mammoplasty as an oncoplastic approach to extensive ductal carcinoma in situ

Background

The aim of this study was to assess the usefulness of the breast segmentectomy with rotation mammoplasty (BSRMP) in conserving therapy for an extensive ductal carcinoma in situ (DCIS) with or without an invasive component.

Methods

Thirty-six women with DCIS visible as large area of microcalcifications distributed out of the retroareolar area regardless of the quadrant were studied prospectively. All the patients underwent BSRMP and axillary procedure (31 sentinel node biopsy, 5 axillary dissection) followed by radiotherapy. In each case, follow-up was carried out carefully and special effort was made to identify postoperative complications. Cosmetic result was judged 6 months after radiotherapy by the patient herself and two surgeons being rated as poor, mediocre, medium, good or excellent.

Results

Operation was completed without any difficulties in all the cases. Appropriate BSRMP was easily done after the skin marking. Regardless of the type of axillary approach, it was conveniently performed. Wound was healed by primary adhesion; skin or breast tissue necrosis did not develop. Neither haematoma nor surgical site infection was observed. In none of the patient, centralisation of the nipple-areola complex (NAC) was needed. Three patients (8.3 %) with close margins (1 mm or less) successfully underwent subsequent re-excision. The scar did not result in any impairment of arm movement. Cosmetic outcome was evaluated by the women as excellent and good in 55 (87 %) and 8 (13 %) cases, respectively, while by the surgeons as excellent, good and medium in 52 (82 %), 8 (13 %), and 3 cases (5 %), respectively.

Conclusions

BSRMP is a simple and safe technique achieving good cosmetic results without NAC centralisation and giving the wide and easy access to axilla for both sentinel node biopsy and lymphadenectomy. It can be helpful in cases of extensive, radially spreading tumours (in particular DCIS or invasive cancers with intraductal component), eccentric lesions, or superficially located cancers when the neighbouring skin is excised. However, due to its limitations (long incision, difficult subsequent mastectomy, possibility of scar placement in the visible area of decollete), a careful patients’ selection should be done. Further studies are needed to assess long-term cosmetic outcomes including delayed post-radiotherapy effects.

Anisotropy of Solid Breast Lesions in 2D Shear Wave Elastography is an Indicator of Malignancy

RATIONALE AND OBJECTIVES

To investigate if anisotropy at two-dimensional shear wave elastography (SWE) suggests malignancy and whether it correlates with prognostic and predictive factors in breast cancer.

MATERIALS AND METHODS

Study group A of 244 solid breast lesions was imaged with SWE between April 2013 and May 2014. Each lesion was imaged in radial and in antiradial planes, and the maximum elasticity, mean elasticity, and standard deviation were recorded and correlated with benign/malignant status, and if malignant, correlated with conventional predictive and prognostic factors. The results were compared to a study group B of 968 solid breast lesions, which were imaged in sagittal and in axial planes between 2010 and 2013.

RESULTS

Neither benign nor malignant lesion anisotropy is plane dependent. However, malignant lesions are more anisotropic than benign lesions (P ≤ 0.001). Anisotropy correlates with increasing elasticity parameters, breast imaging-reporting and data system categories, core biopsy result, and tumor grade. Large cancers are significantly more anisotropic than small cancers (P ≤ 0.001). The optimal anisotropy cutoff threshold for benign/malignant differentiation of 150 kPa(2) achieves the best sensitivity (74%) with a reasonable specificity (63%).

CONCLUSIONS

Anisotropy may be useful during benign/malignant differentiation of solid breast masses using SWE. Anisotropy also correlates with some prognostic factors in breast cancer.

Microcalcifications in 1657 Patients with Pure Ductal Carcinoma in Situ of the Breast: Correlation with Clinical, Histopathologic, Biologic Features, and Local Recurrence

PURPOSE

This study was designed to determine the relationship of microcalcification morphology and distribution with clinical, histopathologic, biologic features, and local recurrence (LR) in patients with pure ductal carcinoma in situ (DCIS) of the breast.

METHODS

All patients with pure DCIS who underwent preoperative mammography at our institution from 1996 through 2009 were identified. Mammographic findings were classified according to the ACR BI-RADS lexicon. Associations between mammographic findings and clinical, histopathologic, biologic characteristics, and LR were analyzed. Statistical inference used multiple logistic regression and Cox proportional hazards regression adjusted for age and confounding due to bias from nonrandomized selection of radiation therapy.

RESULTS

We identified 1657 patients with microcalcifications visualized on mammography. The mean age at diagnosis was 55 years (SD, 11). The mean follow-up was 7 years (range 1-16). Ipsilateral LR was 4 % in segmentectomy (987) and 1.5 % in mastectomy (670) patients. Increased LR risk was seen in patients with dense breast tissue (p < 0.05) and larger DCIS size (p < 0.01). Radiation therapy was associated with a 2.8-fold decrease in the LR risk. Fine linear (branching) microcalcifications were associated with 5.2-fold increase in LR. Extremely dense breast tissue was associated with positive/close margins (p = 0.04) and multicentricity (p < 0.01). Younger women were more likely to have extremely dense breast tissue (p < 0.0001), multicentric disease (p < 0.0004), and undergo mastectomy (p < 0.0001).

CONCLUSIONS

Dense breast tissue, large DCIS size, and fine linear (branching) microcalcifications were associated with increased LR, yet overall LR rates remained low. Extremely dense breast tissue was a risk factor for multicentricity and positive margins in DCIS.

Clinical implications of growth pattern and extension of tumor-associated intraductal carcinoma of the breast

Tumor specimens from 410 patients with primary invasive breast cancer were investigated to identify the clinically relevant features of tumor-associated intraductal component (IDC) surrounding invasive breast cancer. A tumor-associated IDC associated with invasive tumor was mostly localized between the tumor and nipple. Thus, segmental resection of breast tissue is suggested.

INTRODUCTION

The goal of the present study was to identify the clinically relevant features of tumor-associated intraductal component (IDC) surrounding invasive breast cancer.

PATIENTS AND METHODS

The tumor specimens from 410 patients with primary invasive breast cancer were investigated. The distance between the surgical margins and tumor edge (invasive and intraductal areas) was measured prospectively.

RESULTS

Of the 410 investigated patients, 395 were eligible for analysis. An IDC was observed in 241 specimens (61.0%) and was associated with a younger age at diagnosis, postmenopausal status, and positive estrogen receptor, progesterone receptor, and human epidermal growth factor 2 (HER2) expression status. Most cases with tumor-associated ductal carcinoma in situ (DCIS) were found in the upper-outer quadrants of the breasts. An extended intraductal component (EIC) tended to be present in the outer and lower quadrants of the breasts. In the study cohort of 187 patients with tumor-associated DCIS, 1496 surgical margins were investigated. IDC was associated with invasive tumor growth predominantly in the nipple direction. The nipple-associated growth of DCIS correlated with patient age > 40 years, tumor size ≤ 2 cm, poor histologic differentiation of the noninvasive and invasive components, and positive estrogen and progesterone receptor status and negative HER2 status.

CONCLUSIONS

Our data provide evidence that in patients with primary breast cancer, the EIC areas will be mostly segmentally localized between the invasive tumor and the nipple. Therefore, if EIC is present or assumed, surgery should consist of segmental resection of the breast tissue, at least in patients with breast cancer who are > 40 years old, with a tumor size of < 2 cm, and with hormone receptor-positive and HER2-negative, poorly differentiated tumors.

Mammary cancer initiation and progression studied with magnetic resonance imaging

Introduction

Previous work from this laboratory demonstrated that magnetic resonance imaging (MRI) detects early murine mammary cancers and reliably differentiates between in situ and invasive cancer. Based on this previous work, we used MRI to study initiation and progression of murine mammary cancer, and monitor the transition from the in situ to the invasive phase.

Methods

In total, seven female C3(1) SV40 Tag mice were imaged every two weeks between the ages of 8 to 23 weeks. Lesions were identified on T2-weighted images acquired at 9.4 Tesla based on their morphology and growth rates. Lesions were traced manually on MR images of each slice. Volume of each lesion was calculated by adding measurements from individual slices. Plots of lesion volume versus time were analyzed to obtain the specific growth rate (SGR). The time at which in situ cancers (referred to as ‘mammary intraepithelial neoplasia (MIN)’) and invasive cancers were first detected; and the time at which in situ cancers became invasive were recorded.

Results

A total of 121 cancers (14 to 25 per mouse) were identified in seven mice. On average the MIN lesions and invasive cancers were first detected when mice were 13 and 18 weeks old, respectively. The average SGR was 0.47 ± 0.18 week^-1 and there were no differences (P >0.05) between mice. 74 lesions had significantly different tumor growth rates before and after ~17 weeks of age; with average doubling times (DT) of 1.88 and 1.27 weeks, respectively. The average DT was significantly shorter (P <0.0001) after 17 weeks of age. However, the DT for some cancers was longer after 17 weeks of age, and about 10% of the cancers detected did not progress to the invasive stage.

Conclusions

A wide range of growth rates were observed in SV40 mammary cancers. Most cancers transitioned to a more aggressive phenotype at approximately 17 weeks of age, but some cancers became less aggressive. The results suggest that the biology of mammary cancers is extremely heterogeneous. This work is a first step towards use of MRI to improve understanding of factors that control and/or signal the development of aggressive breast cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-014-0495-6) contains supplementary material, which is available to authorized users.

Automatic detection of the nipple in screen-film and full-field digital mammograms using a novel Hessian-based method

Automatic detection of the nipple in mammograms is an important step in computerized systems that combine multiview information for accurate detection and diagnosis of breast cancer. Locating the nipple is a difficult task owing to variations in image quality, presence of noise, and distortion and displacement of the breast tissue due to compression. In this work, we propose a novel Hessian-based method to locate automatically the nipple in screen-film and full-field digital mammograms (FFDMs). The method includes detection of a plausible nipple/retroareolar area in a mammogram using geometrical constraints, analysis of the gradient vector field by mean and Gaussian curvature measurements, and local shape-based conditions. The proposed procedure was tested on 566 mammographic images consisting of 372 randomly selected scanned films from two public databases (mini-MIAS and DDSM), and 194 digital mammograms acquired with a GE Senographe 2000D FFDM system. A radiologist independently marked the centers of the nipples for evaluation of the results. The average error obtained was 6.7 mm (22 pixels) with reference to the center of the nipple as identified by the radiologist. Only two out of the 566 detected nipples (0.35 %) had an error larger than 50 mm. The method was also directly compared with two other techniques for the detection of the nipple. The results indicate that the proposed method outperforms other algorithms presented in the literature and can be used to identify accurately the nipple on various types of mammographic images.

Margin index: a useful tool for the breast surgeon?

BACKGROUND

In breast conservation surgery (BCS) for breast cancer, the appropriate surgical margin is controversial. Margin index, a mathematical relationship between tumor size and closest margin, has been shown to be predictive of the probability of residual cancer after BCS for early stage breast cancer. We applied this tool to the same population of patients at our institution to evaluate its ability to predict residual disease after BCS.

METHODS

We retrospectively reviewed a prospectively maintained database of women undergoing BCS between 1980 and 2010 at the University of Pennsylvania. A total of 246 women underwent re-excision because of close margins. Average margin index between groups with and without residual disease in the re-excision specimen was compared using the Student t-test. A receiver operating curve was created using logistic regression to assess the overall diagnostic ability of the margin index on the presence or absence of residual disease.

RESULTS

Of patients who underwent re-excision, 29% of patients had residual disease. We analyzed several cutoff values for margin index, but none proved to be significant predictors of residual disease. Average margin index was significantly higher for patients without residual disease compared with patients with residual invasive cancer but not for patients with residual ductal carcinoma in situ.

CONCLUSIONS

In women undergoing BCS for early stage breast cancer at our institution, margin index was not predictive of the presence of residual cancer on re-excision. We hypothesize that the predictive ability of a margin index is likely limited by several factors including the presence of ductal carcinoma in situ and the location and extent of the close margin.

Microcalcifications Detected as an Abnormality on Screening Mammography: Outcomes and Followup over a Five-Year Period

Objectives. This study reviewed the outcome of women attending a breast screening program recalled for assessment of microcalcifications and examined the incidence of a breast carcinoma detected during the following five years in any of the women who were given a benign diagnosis at assessment. Method. A retrospective study consisted of 235 clients attending an Australian BreastScreen program in 2003, who were recalled for investigation of microcalcifications detected on screening mammography. Records for the following five years were available for 168 women in the benign outcome group including those who did not require biopsy at initial assessment. Results. Malignant disease was detected in 26.0% (n = 146) of the women who underwent biopsy. None of the women in the benign outcome group, with available five-year follow-up records, developed a subsequent breast cancer, arising from the calcifications initially recalled in 2003. Conclusions. This study highlights the effectiveness of an Australian screening program in diagnosing malignancy in women with screen detected microcalcification. This has been achieved by correctly determining 38% (n = 235) of the women as benign without the need for biopsy or early recall. A low rate of open surgical biopsies was performed with no cancer diagnoses missed at the time of initial assessment.

Patient-calibrated agent-based modelling of ductal carcinoma in situ (DCIS): from microscopic measurements to macroscopic predictions of clinical progression

Ductal carcinoma in situ (DCIS)--a significant precursor to invasive breast cancer--is typically diagnosed as microcalcifications in mammograms. However, the effective use of mammograms and other patient data to plan treatment has been restricted by our limited understanding of DCIS growth and calcification. We develop a mechanistic, agent-based cell model and apply it to DCIS. Cell motion is determined by a balance of biomechanical forces. We use potential functions to model interactions with the basement membrane and amongst cells of unequal size and phenotype. Each cell's phenotype is determined by genomic/proteomic- and microenvironment-dependent stochastic processes. Detailed "sub-models" describe cell volume changes during proliferation and necrosis; we are the first to account for cell calcification. We introduce the first patient-specific calibration method to fully constrain the model based upon clinically-accessible histopathology data. After simulating 45 days of solid-type DCIS with comedonecrosis, the model predicts: necrotic cell lysis acts as a biomechanical stress relief and is responsible for the linear DCIS growth observed in mammography; the rate of DCIS advance varies with the duct radius; the tumour grows 7-10mm per year--consistent with mammographic data; and the mammographic and (post-operative) pathologic sizes are linearly correlated--in quantitative agreement with the clinical literature. Patient histopathology matches the predicted DCIS microstructure: an outer proliferative rim surrounds a stratified necrotic core with nuclear debris on its outer edge and calcification in the centre. This work illustrates that computational modelling can provide new insight on the biophysical underpinnings of cancer. It may 1-day be possible to augment a patient's mammography and other imaging with rigorously-calibrated models that help select optimal surgical margins based upon the patient's histopathologic data.

Mammographycally occult high grade ductal carcinoma in situ (DCIS) as second primary breast cancer, detected with MRI: a case report

Background

Contralateral breast cancer (CLB) is the most common second primary breast cancer in patients diagnosed with breast cancer. The majority of patients harbouring CLB tumours develop the invasive disease. Almost all invasive carcinomas are believed to begin as ductal carcinoma in situ (DCIS) lesions. The sensitivity of MRI for DCIS is much higher than that of mammography.

Case report

We report the case of a woman who was treated with breast conserving therapy 10 years ago. At that time the invasive medullary carcinoma was diagnosed in the left breast. Ten years later mammographically occult DCIS was diagnosed with MRI-guided core biopsy in contralateral breast.

Conclusions

There might be a potential role of MRI screening as part of an annual follow-up for patients diagnosed with breast cancer.

Magnetic resonance imaging of the natural history of in situ mammary neoplasia in transgenic mice: a pilot study

Introduction

Because of the small size of in situ mammary cancers in mouse models, high-resolution imaging techniques are required to effectively observe how lesions develop, grow and progress over time. The purpose of this study was to use magnetic resonance (MR) imaging to track in vivo the transition from in situ neoplasia to invasive cancer in a transgenic mouse model of human cancer.

Methods

MR images of 12 female C3(1) SV40 Tag mice that develop mammary intraepithelial neoplasia (MIN) were obtained. MIN is believed to be similar to human ductal carcinoma in situ (DCIS) and is considered a precursor of invasive tumors. Images were serially obtained from 10-21 weeks of age at 2-3 week intervals. MIN lesions were identified based on their morphology on MR images. Lesions were followed over time and several lesion features were measured including volume, growth rate and morphology. For those MIN lesions that progressed to invasive cancer the progression time was measured.

Results

Overall, 21 MIN lesions were initially detected at an average initial volume of 0.3 ± 0.2 mm³ with an average growth rate of -0.15 ± 0.66 week^-1. Even though all mice were inbred to express the SV40 Tag transgene in the mammary epithelium and expected to develop invasive carcinoma, the individual MIN lesions took vastly different progression paths: (i) 9 lesions progressed to invasive tumors with an average progression time of 4.6 ± 1.9 weeks; (ii) 2 lesions regressed, i.e., were not detected on future images; and (iii) 5 were stable for over 8 weeks, and were demonstrated by a statistical model to represent indolent disease.

Conclusions

To our knowledge, the results reported here are the first measurements of the timescale and characteristics of progression from in situ neoplasia to invasive carcinoma and provide image-based evidence that DCIS may be a non-obligate precursor lesion with highly variable outcomes. In addition, this study represents a first step towards developing methods of image acquisition for identifying radiological characteristics that might predict which in situ neoplasias will become invasive cancers and which are unlikely to progress.

Assessment of breast cancer opportunistic screening by clinical-pathological indicators: a population-based study

BACKGROUND

Although some clinical-pathological features of breast cancers, such as the incidence of ductal cancer in situ (DCIS) and the diameter of invasive tumours, are sensitive indicators of early detection, comprehensive population-based studies of opportunistic screening are needed.

METHODS

Cases of DCIS or invasive breast cancer diagnosed in 1996-2007 were identified from the Ticino Cancer Registry (south of Switzerland). Time trends of age-adjusted incidence and mortality, as well as main clinical-pathological features, such as tumour diameter, AJCC stage and histological grade, were analysed.

RESULTS

A total of 3047 incident cases of female breast cancer were identified. The proportion of DCIS with respect to invasive cases increased from 5.8% in the period 1996-2001 to 6.4% in the period 2002-2007. The median tumour size of invasive cancers decreased from 20 mm in 1996-2001 to 18 mm in 2002-2007 (P<0.0001). An increase in well/moderately differentiated invasive tumours, from 67% in the period 1996-2001 to 73% in 2002-2007 (P<0.001), was detected and resulted in an Annual Percentage Change of incidence of 2.8 (95% confidence interval: 1.3; 4.3).

CONCLUSION

An opportunistic screening strategy can lead to an improvement of prognostic features at diagnosis, but these features are still less favourable than those achieved by organised screening programmes.

Clinical presentation and surgical quality in treatment of ductal carcinoma in situ of the breast

To assess quality of surgical treatment of ductal carcinoma in situ (DCIS) and to compare teaching and non-teaching hospitals that constitute the Comprehensive Cancer Centres of the Middle Netherlands (IKMN), we retrospectively reviewed 499 patients with 502 DCIS lesions treated in the period 1989-2002. In teaching hospitals fewer patients presented with clinical symptoms compared to non-teaching hospitals (15% versus 24.0%, p = 0.01). Finally, 65% of patients underwent breast-conserving surgery and 35% of patients a mastectomy (no significant differences between the two types of hospitals). In teaching hospitals 19% of the patients had a disease-involved or unknown surgical margins versus 13% in non-teaching hospitals (p = 0.04). Twenty patients (4%) received radiation therapy postoperatively with no differences between teaching and non-teaching hospitals (p = 0.98). Quality of surgical treatment is the most important prognostic factor in treatment of DCIS. The quality of excisions should be improved and the exact status of margins should be recorded in pathology reports.

Ductal carcinoma in situ of the breast, a population-based study of epidemiology and pathology

In a population-based series of 2109 women with ductal carcinoma in situ (DCIS) diagnosed in 1995–2000 in New South Wales, Australia, incidence increased by an average of 5.5% a year, mostly between 1995 and 1996 and in women 50–69 years of age. This increase paralleled the increases in mammographic screening. BreastScreen NSW, an organised mammographic screening programme, detected 65% of all DCIS. High-grade lesions were 54% of all lesions and were more likely to be 2+ cm in diameter (OR=2.12, 95%CI 1.46–3.14) than low-grade lesions. In all, 40% of DCIS in women younger than 40 years was 2+ cm in diameter compared with 21% in women 40 years and older. Young age, high grade, mixed architecture and multifocality were significant and independent predictors of 2+ cm DCIS.

The diagnosis and management of pre-invasive breast disease: radiological diagnosis

Pre-invasive disease is most frequently diagnosed in asymptomatic women following detection of microcalcification at mammography. The vast majority is ductal carcinoma in situ. This article summarizes the radiological features of pre-invasive disease and indicates which features are helpful in differentiating between benign and malignant conditions. The value of finding ductal carcinoma in situ at screening, predicting the presence of an invasive focus and methods of percutaneous biopsy of calcification are also addressed.