Real-world analysis of clinical and economic impact of 21-gene recurrence score (RS) testing in early-stage breast cancer (ESBC) in Ireland.

PURPOSE: Results from TAILOR-X suggest that up to 70% of hormone receptor-positive (HR+) node-negative (N0) ESBC patients (pts) may avoid chemotherapy (CT) with RS ≤ 25. We assess clinical and economic impacts of RS testing on treatment using real-world data. METHODS: From October 2011 to February 2019, a retrospective, cross-sectional observational study was conducted of HR+ N0 ESBC pts who had RS testing in Ireland. Pts were classified low risk (RS ≤ 25) and high risk (RS > 25). Clinical risk was calculated. Data were collected via electronic patient records. Cost data were supplied by the National Healthcare Pricing Regulatory Authority. RESULTS: 963 pts. Mean age is 56 years. Mean tumour size is 1.7 cm. 114 (11.8%), 635 (66%), 211 (22%), 3 (0.2%) pts had G1, G2, G3 and unknown G, respectively. 796 pts (82.8%) low RS, 159 (16.5%) high RS and 8 pts (0.7%) unknown RS. 263 pts (26%) were aged ≤ 50 at diagnosis; 117 (45%) had RS 0-15, 63 (24.5%) 16-20, 39 (15.3%) 21-25 and 40 (15.2%) RS 26-100. 4 pts (1.5%) had unknown RS. Post-RS testing, 602 pts (62.5%) had a change in CT decision; 593 changed to hormone therapy (HT) alone. In total, 262 pts received CT. Of pts receiving CT; 138 (53%) had RS > 25, 124 (47%) had RS ≤ 25. Of pts aged ≤ 50, 153 (58%) had high clinical risk, of whom 28 had RS 16-20. Assay use achieved a 62.5% change in treatment with 73% of pts avoiding CT. This resulted in savings of €4 million in treatment costs. Deducting assay costs, savings of €1.9 million were achieved. CONCLUSION: Over the 8 years of the study, a 62.5% reduction in CT use was achieved with savings of over €1,900,000.

Role of bone scan in addition to CT in patients with breast cancer selected for systemic staging.

BACKGROUND: The majority of women with breast cancer present with localized disease. The optimal strategy for identifying patients with metastatic disease at diagnosis remains unclear. The aim of this study was to evaluate the additional diagnostic yield from isotope bone scanning when added to CT staging of the thorax, abdomen and pelvis (CT-TAP) in patients with newly diagnosed breast cancer. METHODS: All patients diagnosed with breast cancer who underwent staging CT-TAP and bone scan between 2011 and 2013 were identified from a prospective database of a tertiary referral breast cancer centre that provides a symptomatic and population-based screening breast service. Criteria for staging included: biopsy-proven axillary nodal metastases; planned neoadjuvant chemotherapy or mastectomy; locally advanced or inflammatory breast cancer and symptoms suggestive of metastases. RESULTS: A total of 631 patients underwent staging by CT-TAP and bone scan. Of these, 69 patients (10·9 per cent) had distant metastasis at presentation, with disease confined to a single organ in 49 patients (71 per cent) and 20 (29 per cent) having metastatic deposits in multiple organs. Bone metastasis was the most common site; 39 of 49 patients had bone metastasis alone and 12 had a single isolated metastatic deposit. All but two of these were to the axial skeleton. No preoperative histological factors identified a cohort of patients at risk of metastatic disease. Omission of the bone scan in systemic staging would have resulted in a false-negative rate of 0·8 per cent. CONCLUSION: For patients diagnosed with breast cancer, CT-TAP is a satisfactory stand-alone investigation for systemic staging.

A Positive Node on Ultrasound-Guided Fine Needle Aspiration Predicts Higher Nodal Burden Than a Positive Sentinel Lymph Node Biopsy in Breast Carcinoma.

INTRODUCTION: Axillary status remains an important prognostic indicator in breast cancer. Certain patients with a positive sentinel node (SLNB) may not benefit from axillary clearance (AC). Uncertainty remains if this approach could be applied to patients diagnosed with axillary metastases on ultrasound-guided fine needle aspiration cytology (USFNAC). The aim of this study was to compare nodal burden in patients with positive USFNAC and a positive SLNB. METHODS: A retrospective study was performed involving all BC patients between 2007 and 2014 who had either pre-operative USFNAC or a SLNB. Patient/tumour characteristics and nodal burden were examined in all patients proceeding to AC. RESULTS: 974 patients were eligible for analysis. 439 patients (45 %) had positive USFNAC and 535 (55 %) had a positive SLNB. USFNAC-positive patients were more likely to undergo mastectomy (Chi-square test; p < 0.001), have extra-nodal extension (p < 0.001), be oestrogen receptor negative (p < 0.001) and be HER2 positive (p < 0.001). The median total number of lymph nodes (LNs) excised during AC was higher in the USFNAC group (Mann-Whitney test; 23 vs. 21; p < 0.001). The median total number of involved LNs was 3 (range 1-47) in FNAC-positive patients versus 1 (range 1-37) in SLNB-positive patients (p < 0.001). The median number of involved LNs in level 1 was 3 in FNAC-positive patients versus 1 in SLNB-positive patients (p < 0.001). Within the SLN-positive group, 49 % of the patients had only one involved LN, 28 % had two nodes involved and 23 % had ≥3. In comparison, within the FNAC-positive group only 13 % of the patients had one involved LN, 12 % had two nodes involved and 74 % had ≥3. CONCLUSION: Patients with positive USFNAC have more aggressive clinico-pathological characteristics and higher nodal burden compared to SLNB-positive patients. Currently, the authors advocate that patients not receiving neoadjuvant chemotherapy, with a positive USFNAC, should proceed directly to an axillary ALND.

Integrating central nervous system metagenomics and host response for diagnosis of tuberculosis meningitis and its mimics.

The epidemiology of infectious causes of meningitis in sub-Saharan Africa is not well understood, and a common cause of meningitis in this region, Mycobacterium tuberculosis (TB), is notoriously hard to diagnose. Here we show that integrating cerebrospinal fluid (CSF) metagenomic next-generation sequencing (mNGS) with a host gene expression-based machine learning classifier (MLC) enhances diagnostic accuracy for TB meningitis (TBM) and its mimics. 368 HIV-infected Ugandan adults with subacute meningitis were prospectively enrolled. Total RNA and DNA CSF mNGS libraries were sequenced to identify meningitis pathogens. In parallel, a CSF host transcriptomic MLC to distinguish between TBM and other infections was trained and then evaluated in a blinded fashion on an independent dataset. mNGS identifies an array of infectious TBM mimics (and co-infections), including emerging, treatable, and vaccine-preventable pathogens including Wesselsbron virus, Toxoplasma gondii, Streptococcus pneumoniae, Nocardia brasiliensis, measles virus and cytomegalovirus. By leveraging the specificity of mNGS and the sensitivity of an MLC created from CSF host transcriptomes, the combined assay has high sensitivity (88.9%) and specificity (86.7%) for the detection of TBM and its many mimics. Furthermore, we achieve comparable combined assay performance at sequencing depths more amenable to performing diagnostic mNGS in low resource settings.

Removal of multiple sentinel lymph nodes in patients with breast cancer: defining the "correct" node.

PURPOSE: Sentinel node biopsy is routinely used for axillary staging in patients with clinical and radiological node negative breast cancer. The number of nodes removed at surgery is highly variable. A mean of 2.4 nodes is frequently seen in the larger series. Removal of multiple (3 or more) nodes does not improve the accuracy but increases both operative time and pathological analysis. The aim of the current study was to define the correct sentinel node based on uptake of blue dye and radioactive counts. METHODS: The sentinel node was identified in 121 consecutive patients using isosulfan blue dye and radioisotope. Nodes were labelled sequentially as (i) Hot (ii) Blue or (iii) Hot and Blue and submitted for pathological analysis. Data pertaining to blue dye uptake and radioisotope counts were recorded prospectively. This was correlated with pathological and scintigraphy findings. RESULTS: Thirty eight (32%) patients had a positive sentinel node. "Hot and Blue" nodes were found in 105 cases. The number of hot and blue nodes correlated exactly with the number seen on scintigraphy. "Blue" nodes were found in one case. "Hot" nodes were found in 15 cases. In cases where a "hot and blue" node was positive there were no further "hot" or "blue" nodes found to be positive. CONCLUSION: Removal of multiple sentinel nodes can be avoided by removing all hot and blue nodes and correlating with findings on lymphoscintigraphy. When present (87% of cases), the "hot and blue" node accurately predicts the pathological burden of the axilla.

Columnar cell lesions of the breast.

Columnar cell lesions of the breast comprise a group of conditions characterized by dilation of terminal duct lobular units lined by columnar epithelial cells, ranging from one or two layers of benign epithelium to stratified epithelium with atypia. Although these lesions have been recognized by pathologists for many years, they have recently assumed a new significance due to their increased detection as mammographic calcification, the potential for overdiagnosis as ductal carcinoma in situ (DCIS) and their possible relationship to invasive carcinoma. This short overview aims to outline the pathological features and likely clinical significance of these lesions, with emphasis on diagnostic criteria, terminology and classification, and management strategies.

Impact of receptor phenotype on nodal burden in patients with breast cancer who have undergone neoadjuvant chemotherapy.

BACKGROUND: Optimal evaluation and management of the axilla following neoadjuvant chemotherapy (NAC) in patients with node-positive breast cancer remains controversial. The aim of this study was to examine the impact of receptor phenotype in patients with nodal metastases who undergo NAC to see whether this approach can identify those who may be suitable for conservative axillary management. METHODS: Between 2009 and 2014, all patients with breast cancer and biopsy-proven nodal disease who received NAC were identified from prospectively developed databases. Details of patients who had axillary lymph node dissection (ALND) following NAC were recorded and rates of pathological complete response (pCR) were evaluated for receptor phenotype. RESULTS: Some 284 patients with primary breast cancer and nodal metastases underwent NAC and subsequent ALND, including two with bilateral disease. The most common receptor phenotype was luminal A (154 of 286 tumours, 53·8 per cent), with lesser proportions accounted for by the luminal B-Her2 type (64, 22·4 per cent), Her2-overexpressing (38, 13·3 per cent) and basal-like, triple-negative (30, 10·5 per cent) subtypes. Overall pCR rates in the breast and axilla were 19·9 per cent (54 of 271 tumours) and 37·4 per cent (105 of 281) respectively. Axillary pCR rates were highest in the Her2-overexpressing group (27 of 35, 77 per cent) and lowest in the luminal A group (35 of 153, 22·9 per cent) (P < 0·001). Nodal burden (median number of positive nodes excised) was lower in the Her2-overexpressing group compared with the luminal A group (0 versus 3; P < 0·001). CONCLUSION: Her2 positivity was associated with increased rates of axillary pCR and reduced nodal burden following NAC.

Diagnostic accuracy of core biopsy for ductal carcinoma in situ and its implications for surgical practice.

BACKGROUND: Core biopsy is considered to be a highly accurate method of gaining a preoperative histological diagnosis of breast cancer. Ductal carcinoma in situ (DCIS) is often impalpable and is a more subtle form of breast cancer. AIM: To investigate the accuracy of core biopsy in the diagnosis of cancer in patients with DCIS. METHODS: All patients who had invasive cancer (n = 959) or DCIS (n = 92) that was confirmed by excision between 1999 and 2004 were identified. The diagnostic methods, histology of the core biopsy specimen and excision histology were reviewed in detail. RESULTS: Core biopsy was attempted in 88% (81/92) of patients with DCIS and in 91% (874/959) of those with invasive disease. Of those patients who underwent core biopsy, a diagnosis of carcinoma on the initial core was made in 65% (53/81) of patients with DCIS compared with 92% (800/874) of patients with invasive disease (p<0.0001). Smaller lesion size (p = 0.005) and lower grade (p = 0.03) were associated with increased risk for a negative or non-diagnostic core in patients with DCIS. The nature of the mammographic lesion or the method of biopsy did not affect the probability of an accurate core biopsy. Patients who had a preoperative diagnosis of DCIS by core biopsy had a reoperation rate of 36% compared with 65% of those that did not have a preoperative diagnosis (p = 0.007). CONCLUSION: Although core biopsies are highly accurate forms of obtaining a preoperative diagnosis in patients with invasive breast cancer, this is not the case in DCIS. As the number of surgical procedures can be reduced by core biopsy, it is still of considerable value in the management of DCIS.

The NHS breast screening programme (pathology) EQA: experience in recent years relating to issues involved in individual performance appraisal.

BACKGROUND: The original role of the National Health Service breast screening programme (pathology) external quality assessment (EQA) scheme was educational; it aimed to raise standards, reinforce use of common terminology, and assess the consistency of pathology reporting of breast disease in the UK. AIMS/METHODS: To examine the performance (scores) of pathologists participating in the scheme in recent years. The scheme has evolved to help identify poor performers, reliant upon setting an acceptable cutpoint. Therefore, the effects of different cutpoint strategies were evaluated and implications discussed. RESULTS/CONCLUSIONS: Pathologists who joined the scheme improved over time, particularly those who did less well initially. There was no obvious association between performance and the number of breast cancer cases reported each year. This is not unexpected because the EQA does not measure expertise, but was established to demonstrate a common level of performance (conformity to consensus) for routine cases, rather than the ability to diagnose unusual/difficult cases. A new method of establishing cutpoints using interquartile ranges is proposed. The findings also suggest that EQA can alter a pathologist's practice: those who leave the scheme (for whatever reason) have, on average, marginally lower scores. Consequently, with the cutpoint methodology currently used (which is common to several EQA schemes) there is the potential for the cutpoint to drift upwards. In future, individuals previously deemed competent could subsequently be erroneously labelled as poor performers. Due consideration should be given to this issue with future development of schemes.

Impact of a national external quality assessment scheme for breast pathology in the UK.

BACKGROUND: This article presents the results and observed effects of the UK National Health Service Breast Screening Programme (NHSBSP) external quality assurance scheme in breast histopathology. AIMS/METHODS: The major objectives were to monitor and improve the consistency of diagnoses made by pathologists and the quality of prognostic information in pathology reports. The scheme is based on a twice yearly circulation of 12 cases to over 600 registered participants. The level of agreement was generally measured using kappa statistics. RESULTS: Four main situations were encountered with respect to diagnostic consistency, namely: (1) where consistency is naturally very high-this included diagnosing in situ and invasive carcinomas (and certain distinctive subtypes) and uncomplicated benign lesions; (2) where the level of consistency was low but could be improved by making guidelines more detailed and explicit-this included histological grading; (3) where consistency could be improved but only by changing the system of classification-this included classification of ductal carcinoma in situ; and (4) where no improvement in consistency could be achieved-this included diagnosing atypical hyperplasia and reporting vascular invasion. Size measurements were more consistent for invasive than in situ carcinomas. Even in cases where there is a high level of agreement on tumour size, a few widely outlying measurements were encountered, for which no explanation is readily forthcoming. CONCLUSIONS: These results broadly confirm the robustness of the systems of breast disease diagnosis and classification adopted by the NHSBSP, and also identify areas where improvement or new approaches are required.

New ASCO/CAP guideline recommendations for HER2 testing increase the proportion of reflex in situ hybridization tests and of HER2 positive breast cancers.

Accurate determination of tumour human epidermal growth factor receptor type 2 (HER2) status is critical for optimal treatment of breast cancer. In October 2013, the American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) issued joint updated guideline recommendations for HER2 testing in breast cancer, with a revised algorithm for interpretation of immunohistochemistry (IHC) and in situ hybridisation (ISH) results. This study investigates the impact on HER2 IHC categorisation, implication for reflex ISH testing and potential for identification of false negative IHC. HER2 IHC preparations on 251 invasive breast tumours, originally reported according to 2007 guidelines, were re-scored using 2013 guidelines and the diagnostic categories compared. The results of ISH testing on a separate cohort of 32 breast tumours reported as HER2 IHC 2+ following the introduction of the 2013 guidelines, that would have been designated 1+ according to 2007, were reviewed. Application of 2013 guidelines resulted in a decrease in tumours classified as HER2 negative (83/251 vs 144/251) and a comparable increase in those classified as equivocal (2+) (139/251 vs 80/251). Relatively few tumours were re-classified as positive (29/251 vs 27/251). Furthermore, 3/32 breast cancer cases (HER2 IHC 2+ as per 2013 guidelines, 1+ using 2007 guidelines) were HER2 ISH positive. Application of the 2013 guidelines increases the HER2 IHC equivocal (2+) category and requirement for reflex ISH testing. The reduced threshold for ISH testing identifies some patients with HER2 positive breast cancer whose tumours would have been categorised as HER2 negative according to the 2007 guidelines.

Consistency in recognizing microinvasion in breast carcinomas is improved by immunohistochemistry for myoepithelial markers.

Microinvasion is the smallest morphologically identifiable stage of invasion. Its presence and distinction from in situ carcinoma may have therapeutic implications, and clinical staging also requires the recognition of this phenomenon. Microinvasion is established on the basis of several morphological criteria, which may be difficult and not perfectly reproducible among pathologists. The aim of this study was to assess the consistency of diagnosing microinvasion in the breast on traditional haematoxylin and eosin (HE) stained slides and to evaluate whether immunohistochemistry (IHC) for myoepithelial markers could improve this. Digital images were generated from representative areas of 50 cases stained with HE and IHC for myoepithelial markers. Cases were specifically selected from the spectrum of in situ to microinvasive cancers. Twenty-eight dedicated breast pathologists assessed these cases at different magnifications through a web-based platform in two rounds: first HE only and after a washout period by both HE and IHC. Consistency in the recognition of microinvasion significantly improved with the use of IHC. Concordance rates increased from 0.85 to 0.96, kappa from 0.5 to 0.85, the number of cases with 100% agreement rose from 9/50 to 25/50 with IHC and the certainty of diagnosis also increased. The use of IHC markedly improves the consistency of identifying microinvasion. This corroborates previous recommendations to use IHC for myoepithelial markers to clarify cases where uncertainty exists about the presence of microinvasion. Microinvasive carcinoma is a rare entity, and seeking a second opinion may avoid overdiagnosis.

Linked chromosome 16q13 chemokines, macrophage-derived chemokine, fractalkine, and thymus- and activation-regulated chemokine, are expressed in human atherosclerotic lesions.

Chemokines are important mediators of macrophage and T-cell recruitment in a number of inflammatory pathologies, and chemokines expressed in atherosclerotic lesions may play an important role in mononuclear cell recruitment and macrophage differentiation. We have analyzed the expression of the linked chromosome 16q13 genes that encode macrophage-derived chemokine (MDC/CCL22), thymus- and activation-regulated chemokine (TARC/CCL17), and the CX(3)C chemokine fractalkine (CX(3)CL1) in primary macrophages and human atherosclerotic lesions by reverse transcription-polymerase chain reaction and immunohistochemistry. We show that macrophage expression of the chemokines MDC, fractalkine, and TARC is upregulated by treatment with the Th2-type cytokines interleukin-4 and interleukin-13. High levels of MDC, TARC, and fractalkine mRNA expression are seen in some, but not all, human arteries with advanced atherosclerotic lesions. Immunohistochemistry shows that MDC, fractalkine, and TARC are expressed by a subset of macrophages within regions of plaques that contain plaque microvessels. We conclude that MDC, fractalkine, and TARC, which are chromosome 16q13 chemokines, could play a role in mononuclear cell recruitment into atherosclerotic lesions and influence the subsequent inflammatory response. Macrophage-expressed chemokines upregulated by interleukin-4 may be useful surrogate markers for the presence of Th2-type immune responses in human atherosclerotic lesions.

Phenotypic analysis of familial breast cancer: comparison of BRCAx tumors with BRCA1-, BRCA2-carriers and non-familial breast cancer.

AIMS: Women with inherited pathogenic mutations in the BRCA1 or BRCA2 genes have up to an 85% risk of developing breast cancer in their lifetime. However, only about 20% of familial breast cancer is attributed to mutations in BRCA1 and BRCA2, while a further 5-10% are attributed to mutations in other rare susceptibility genes such as TP53, STK11, PTEN, ATM and CHEK2. Despite extensive efforts to explain the missing heritability of this disease, the majority of familial clustering in breast cancer remains largely unexplained. We aim to analyze the pathology of familial cases of which no pathogenic mutation is yet identified. METHODS: We compared the pathological phenotype of BRCA1/BRCA2 negative familial breast cancer (BRCAx) to BRCA1-positive, BRCA2-positive and sporadic cases without a family history. Age-adjusted analysis is summarized in odd's ratios and confidence intervals for tumor type, grade, lymph node, ER and HER2 status. RESULTS: We found non-familial cases to be more likely to be ER positive (P = 0.041) as compared with BRCAx tumors. More cases of lobular carcinoma were found with BRCAx as compared to BRCA1 tumors (P = 0.05). After multivariate logistic regression analysis, BRCAx tumors are more likely ER positive (P = 0.001) and HER2 positive (P = 0.047) in comparison to BRCA1. Conversely, BRCAx cases are less likely to be ER positive (P = 0.02) but more likely to be HER2 positive (P = 0.021) as compared with BRCA2 tumors. CONCLUSION: Our findings suggest that BRCA1, BRCA2 and BRCAx tumors differ in phenotype from non-familial and familial BRCA1-positive and BRCA2-positive tumors. Further studies will need to be performed in this important population in order to develop strategies for early detection and prevention.

Axillary nodal burden in primary breast cancer patients with positive pre-operative ultrasound guided fine needle aspiration cytology: management in the era of ACOSOG Z011.

INTRODUCTION: Recent years have seen a dramatic shift to more conservative management of the axilla in patients with a positive sentinel lymph node biopsy (SLNB). Identification of nodal disease with positive pre-operative ultrasound guided axillary fine needle aspiration cytology (AUS/FNAC) may represent a higher axillary disease burden mandating an axillary clearance and thus an upfront SLNB may be avoided. The aims of this study were to quantify nodal burden in patients with positive pre-operative AUS/FNAC and identify patients who may have been able to avoid an axillary clearance (ALND) based on ACOSOG Z011 criteria. METHODS: A retrospective review of a prospectively maintained database identified patients with positive pre-operative AUS/FNAC between 2007 and 2012. Core biopsies were excluded. Demographic and tumour characteristics were analysed. Eligibility for ACOSOG Z011 criteria was assessed and patients who may have avoided ALND were identified. RESULTS: 432 patients were identified with positive AUS/FNAC. 85 patients were excluded leaving 347 for analysis. Median age was 56 years (22-87), median tumour size was 25 mm (1.5 mm-150 mm) and median tumour pathology was grade 3 (50%) and invasive ductal carcinoma (82%). Median number of nodes removed at ALND was 23 (1-55) with a median number of positive nodes being 4 (1-47). 134 (39%) patients had ≤2 positive nodes identified on ALND making them eligible for the ACOSOG Z011 study. When other ACOSOG Z011 exclusion factors were applied only 27 (7.8%) patients may have avoided ALND. CONCLUSIONS: Nodal positivity on AUS/FNAC is associated with higher axillary disease burden. Few patients would satisfy ACOSOG/Z011 criteria and avoid ALND making an upfront SLNB unnecessary.

A human CD46 transgenic pig model system for the study of discordant xenotransplantation.

BACKGROUND: The chronic shortage in the supply of human organs available for allotransplantation has turned attention toward the use of animals as potential donors, with pigs as the most likely species under consideration. Hyperacute rejection, the initial and immediate barrier to a pig-to-primate xenograft, has been addressed by generation of transgenic pigs that express the human membrane-bound complement-regulatory proteins CD59 and/or CD55. Difficulty has been encountered in generation of transgenic animals that express a third membrane-bound complement-regulatory protein, CD46. METHODS: We have generated transgenic animals by using a large genomic construct that encompasses the entire human CD46 gene. RESULTS: We report the first description of transgenic mice and pigs that express high levels of human CD46 in a cell and tissue type-specific manner, resembling patterns of endogenous CD46 expression observed in human tissues. Furthermore, when human CD46 transgenic porcine hearts were transplanted into baboons, the grafts did not succumb to hyperacute rejection, and survival extended for up to 23 days. Under the same conditions, nontransgenic grafts underwent hyperacute rejection within 90 min. CONCLUSIONS: This is the first report to describe generation of transgenic pigs that express human CD46, and the first in vivo demonstration of the ability of human CD46 expressed on pig organs to regulate complement activation and overcome hyperacute rejection upon transplantation of a vascularized organ into nonhuman primates.

Cytological and architectural heterogeneity in ductal carcinoma in situ of the breast.

AIM: The traditional architecture based classification system of ductal carcinoma in situ (DCIS) has been criticised on the grounds that individual lesions often show more than one pattern resulting in a large mixed category. New DCIS classification systems have emphasised the importance of cytological grade, which is reputed to be more uniformly expressed throughout a lesion. This study investigates the hypothesis that cytological heterogeneity is less common than architectural heterogeneity within DCIS lesions. METHODS: 121 cases of DCIS were graded as poorly, intermediately, or well differentiated according to a recently developed classification system that employs cytonuclear morphology as the major diagnostic criterion. Cases were categorised as pure when only one grade was present and as mixed if more than one grade was observed. Architecturally the cases were classified as solid, cribriform, micropapillary, or papillary and were described as pure if only one architectural pattern was present and as mixed if more than one pattern was seen. The incidence of cytological heterogeneity was compared with that of architectural heterogeneity. The presence of necrosis was assessed as an independent parameter and the relation to DCIS grade evaluated. RESULTS: Using the cytology based classification system 102 cases (84%) were classified as pure (65 poorly differentiated, 25 intermediately differentiated, and 12 well differentiated) and 19 cases (16%) as mixed. Extensive necrosis was observed in 61 (50%) cases and was closely correlated to DCIS grade. Architecturally 46 cases (38%) were classified as pure (38 solid, 5 cribriform, 2 micropapillary, and 1 papillary) and 75 (62%) as mixed. CONCLUSIONS: Cytological heterogeneity is much less common than architectural heterogeneity in DCIS lesions. The assessment of cytonuclear morphology is therefore likely to provide more consistent information about DCIS, particularly in small biopsy specimens where only part of the lesion may be available for examination.

Angiogenesis, thrombospondin, and ductal carcinoma in situ of the breast.

Angiogenesis, the growth of new vessels from existing vasculature, plays an essential role in tumour development. The process involves interaction between a variety of cells, growth factors, and components of the extracellular matrix, regulated by pro-angiogenic and anti-angiogenic factors. This review profiles these factors, outlines the available methods for measuring new vessel formation, and discusses the importance of angiogenesis in breast cancer, with emphasis on ductal carcinoma in situ.

Thrombospondin 1 protein expression relates to good prognostic indices in ductal carcinoma in situ of the breast.

AIM: Angiogenesis plays an important role in tumour growth and has been shown to occur around both in situ and invasive tumours. The degree of angiogenesis within tumours depends on the balance of pro-angiogenic and anti-angiogenic factors. One such anti-angiogenic factor is thrombospondin 1 (TSP-1). This study investigates the pattern of expression of TSP-1 in ductal carcinoma in situ (DCIS) of the breast and its relation to the surrounding microvessel pattern and density. MATERIALS/METHODS: The expression of TSP-1 was studied in formalin fixed, paraffin wax embedded sections from 58 cases of pure DCIS, using a monoclonal antibody against TSP-1 and the avidin-biotin-diaminobenzidine immunoperoxidase detection system. Vessels were stained with a monoclonal antibody to the endothelial cell marker CD31. Stromal microvessel density was assessed by counting "hot spots" within 500 micro m of the basement membrane of involved ducts using a 25 point Chalkey graticule. RESULTS: TSP-1 staining of the basement membrane around duct spaces with DCIS was seen in 69% of cases. In addition, staining of the stroma between involved duct spaces was seen in 31% of cases, with a fibrillary pattern identical to that seen in invasive breast carcinomas. In 12% of cases no staining for TSP-1 was seen. Two patterns of vascularity were identified. A cuff of vessels immediately adjacent to the basement membrane of ducts with DCIS was seen in 71% of cases. The presence of stromal TSP-1 was significantly associated with DCIS showing no/little necrosis (p = 0.01) and no/little periductal inflammation (p = 0.04). There was a trend between the presence of stromal TSP-1 and tumour cell negativity for p53 (p = 0.087). The stromal microvessel Chalkey point count ranged between 3.33 and 16. An increased stromal microvessel count was associated with high histological grade (p = 0.02), extensive necrosis (p = 0.047), and pronounced periductal inflammation (p = 0.049). There was no association between the presence of stromal TSP-1 and stromal microvessel density. CONCLUSIONS: TSP-1 is expressed in the stroma around DCIS and in the immediately adjacent basement membrane. Expression of stromal TSP-1 is lost in DCIS with more aggressive histological features. The absence of a relation with microvessel density suggests that other angiogenic factors may play an important role in DCIS.