Recent technological advances have improved the whole slide imaging (WSI) scanner quality and reduced the cost of storage, thereby enabling the deployment of digital pathology for routine diagnostics. In this paper we present the experiences from two Swedish sites having deployed routine large-scale WSI for primary review. At Kalmar County Hospital, the digitization process started in 2006 to reduce the time spent at the microscope in order to improve the ergonomics. Since 2008, more than 500,000 glass slides have been scanned in the routine operations of Kalmar and the neighboring Linköping University Hospital. All glass slides are digitally scanned yet they are also physically delivered to the consulting pathologist who can choose to review the slides on screen, in the microscope, or both. The digital operations include regular remote case reporting by a few hospital pathologists, as well as around 150 cases per week where primary review is outsourced to a private clinic. To investigate how the pathologists choose to use the digital slides, a web-based questionnaire was designed and sent out to the pathologists in Kalmar and Linköping. The responses showed that almost all pathologists think that ergonomics have improved and that image quality was sufficient for most histopathologic diagnostic work. 38 ± 28% of the cases were diagnosed digitally, but the survey also revealed that the pathologists commonly switch back and forth between digital and conventional microscopy within the same case. The fact that two full-scale digital systems have been implemented and that a large portion of the primary reporting is voluntarily performed digitally shows that large-scale digitization is possible today.

Background. Male breast cancer (MBC) is an uncommon disease and there is limited information on the prognostic impact of routinely used clinicopathological parameters. Material and methods. In a retrospective setting, we reviewed 197 MBC patients with accessible paraffin-embedded tumor tissue and clinicopathological data. Immunohistochemical (IHC) stainings were performed on tissue microarrays and histological grading on conventional slides. Cox proportional regression models were applied for uni- and multivariate analyses using breast cancer death as the event. Results. Estrogen receptor (ER) and progesterone receptor positivity were demonstrated in 93% and 77% of patients, respectively. Nottingham histologic grade (NHG) III was seen in 41% and HER2 positivity in 11%. Classification into molecular subtypes using IHC markers according to three alternative definitions revealed luminal A and luminal B in 81% vs. 11%; 48% vs. 44% and 41% vs. 42% of cases. Two cases of basal-like were identified, but no cases of HER2-like. Factors associated with an increased risk of breast cancer death were node positivity (HR 4.5; 95% CI 1.8-11.1), tumor size >20 mm (HR 3.3; 95% CI 1.4-7.9) and ER negativity (HR 10.9; 95% CI 3.2-37.9). No difference in breast cancer death between the luminal subgroups was demonstrated, regardless of definition. Conclusion. MBC tumors were more often of high grade, whereas HER2 overexpression was as frequent as in FBC. Lymph nodes, tumor size and ER status were independent predictors of breast cancer death. The prognostic impact of molecular subtyping in MBC seems to differ from that previously established in FBC.

Assessment of proliferation is important in female breast cancer and individual treatment decisions are based upon its results, especially in the luminal subgroups. Gene expression analyses fail to group male breast cancer into the intrinsic subgroups previously established in female breast cancer. Even though proliferation has been shown to divide male breast cancer into molecular subgroups with different prognoses, the clinical importance of proliferation markers has not yet been elucidated. Previous studies in male breast cancer have demonstrated contradictory results regarding the prognostic impact of histological grade and Ki-67, parameters strongly associated with proliferation. The aim of the present project was to study proliferation in male breast cancer by assessing other proliferation-related markers viz. cyclins A, B, D1 and mitotic count. A total of 197 male breast cancer cases with accessible paraffin-embedded material and outcome data were investigated. Immunohistochemical stainings were performed on tissue microarrays. Kaplan–Meier estimates and the Cox proportional regression models were used for survival analyses with breast cancer death as the event. The subset of patients with high expression of cyclin A (hazard ratio (HR) 3.7; P=0.001) and B (HR 2.7; P=0.02) demonstrated a poorer survival. Furthermore, high mitotic count was associated with an increased risk of breast cancer death (HR 2.5; P=0.01). In contrast, cyclin D1 overexpression was predictive of better breast cancer survival (HR 0.3; P=0.001). In conclusion, high levels of cyclin A and B expression and an elevated mitotic count result in a two to threefold higher risk for breast cancer death, whereas cyclin D1 overexpression halves the risk. The clinical utility of these proliferation markers needs further elucidation.

Abstract Purpose: To characterize male breast cancer (MBC) by evaluating established histopathological parameters and their prognostic value. Methods: 197 male patients with invasive breast cancer and available paraffin-embedded tumor tissue were retrospectively assessed. Patient files were reviewed for clinicopathological data. Tumors were re-evaluated for histologic grading on conventional sections. Immunohistochemical (IHC) stainings for estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), silver-enhanced in situ hybridization (SISH), Ki-67, CK5/6 and epidermal growth factor receptor (EGFR) were performed on tissue micro arrays. Data on vital status and cause of death were retrieved from the Cause of Death Registry. Cox proportional regression models were used for uni- and multivariate analyses. Results: ER and PgR positivity was demonstrated in 93 and 78 % of patients, respectively. Nottingham histologic grade III was seen in 41% and HER2 positivity in 11% of all patients. Defining molecular phenotypes using IHC markers revealed luminal (ER+ and/or PgR+, and HER2−) in 83%, luminal/HER2+ (ER+ and/or PgR+, and HER2+) in 11%, basal-like (ER-,PgR-,HER2−,EGFR+ and/or CK5/6 +) in 1%, but no cases of HER2-like or unclassified. Node-positivity (HR 4.6; 95% CI 1.9−11.4), tumor size > 20 mm (HR 2.3; 95% CI 1.1−5.0) and ER-negativity (HR 5.2; 95% CI 1.9−14.2) were significant risk factors for breast cancer death. Grade, HER2 status, Ki-67, or age did not demonstrate independent prognostic information. No difference in breast cancer deaths was demonstrated between luminal and luminal/HER2. Conclusion: Male breast cancer tumors seem to be of grade III more often than female breast cancer, whereas HER2 expression appears equally common. In our study, the most important predictors for breast cancer death in male breast cancer were lymph nodes, tumor size and ER status. The most common molecular phenotype was luminal. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-19-04.

Background: Several studies suggest that total breastfeeding time reduces breast cancer risk. The underlying mechanisms are unclear. Whether breastfeeding also affects the prognosis is not yet investigated. A number of tumour characteristics, i.e. histological type of cancer, grade, tumour size, Nottingham prognostic index, vascular invasion and DNA-ploidy, have been demonstrated to be of prognostic value.Methods: We have searched for a possible link between these prognostic markers and breastfeeding time, age at first child and number of children. 250 women treated for breast cancer have answered a questionnaire.Results: No significant interactions were found possibly with one exception, LVI vs. age at first child. We found, significant correlations between lobular cancer, and thereby also DNA-ploidy, and age at first childbirth.Conclusions: We have found that lobular cancer (and thereby also diploid tumours) are connected, independently, to age at first childbirth and possibly also to number of children but no other correlations between reproductive data, breastfeeding included, and prognostic markers used in this study were found. (C) 2010 Published by Elsevier Ltd.

BACKGROUND:Two recently developed clinical prediction rules aim to anticipate the lack of nonsentinel lymph node metastases and the involvement of less than 4 lymph nodes in breast cancer patients with positive sentinel lymph nodes (SLNs). METHODS:The University of Louisville Breast SLN Study clinical prediction rules were validated on an independent set of SLN-positive patients with tumors < or = 15 mm. RESULTS:The data on 475 and 473 patients, respectively, were used for the validation. The areas under the receiver operating characteristic curves were similar to the originals for both predictive tools (.70 and .76). The lowest score of 1 identified 5 of 7 patients with disease limited to the SLNs and 161 of 165 as having less than 4 involved lymph nodes. CONCLUSIONS:A subset of patients with SLN-only involvement and less than 4 metastatic lymph nodes can probably be identified by means of the Louisville clinical prediction rules, but prediction of the lack of non-SLN metastasis seems less reliable.

Sentinel lymph node (SLN) biopsy has become the preferred method for the nodal staging of early breast cancer, but controversy exists regarding its universal use and consequences in small tumors. 2929 cases of breast carcinomas not larger than 15 mm and staged with SLN biopsy with or without axillary dissection were collected from the authors′ institutions. The pathology of the SLNs included multilevel hematoxylin and eosin (HE) staining. Cytokeratin immunohistochemistry (IHC) was commonly used for cases negative with HE staining. Variables influencing SLN involvement and non-SLN involvement were studied with logistic regression. Factors that influenced SLN involvement included tumor size, multifocality, grade and age. Small tumors up to 4 mm (including in situ and microinvasive carcinomas) seem to have SLN involvement in less than 10%. Non-SLN metastases were associated with tumor grade, the ratio of involved SLNs and SLN involvement type. Isolated tumor cells were not likely to be associated with further nodal load, whereas micrometastases had some subsets with low risk of non-SLN involvement and subsets with higher proportion of further nodal spread. In situ and microinvasive carcinomas have a very low risk of SLN involvement, therefore, these tumors might not need SLN biopsy for staging, and this may be the approach used for very small invasive carcinomas. If an SLN is involved, isolated tumor cells are rarely if ever associated with non-SLN metastases, and subsets of micrometastatic SLN involvement may be approached similarly. With macrometastases the risk of non-SLN involvement increases, and further axillary treatment should be generally indicated.

This study aimed at identifying factors related to sentinel lymph node (SLN) involvement in patients with tubular, cribriform, mucinous or papillary breast carcinoma and those related to non-SLN metastases if an SLN was positive. Multivariate analyses involved logistic and stepwise regressions. The SLNs harboured metastases in 85 of 572 cases, 78 of whom underwent axillary dissection; 19 presented non-SLN positive disease. Lack of lymphovascular invasion, a tumour size ⩽10mm and a single SLN removed were the factors predicting an SLN metastasis rate <10%, and patients with these features could be candidates for no surgical axillary staging. A positive SLN proportion of ⩽50% and no lymphovascular invasion were associated with a <10% rate of non-SLN invasion; patients with a positive SLN and these features could be candidates for the omission of completion axillary dissection. The opposite presentation of these factors would mandate SLN biopsy and axillary dissection, respectively.

Abstract Background A common approach in exploring register data is to find relationships between outcomes and predictors by using multiple regression analysis (MRA). If there is more than one outcome variable, the analysis must then be repeated, and the results combined in some arbitrary fashion. In contrast, Canonical Correlation Analysis (CCA) has the ability to analyze multiple outcomes at the same time. One essential outcome after breast cancer treatment is recurrence of the disease. It is important to understand the relationship between different predictors and recurrence, including the time interval until recurrence. This study describes the application of CCA to find important predictors for two different outcomes for breast cancer patients, loco-regional recurrence and occurrence of distant metastasis and to decrease the number of variables in the sets of predictors and outcomes without decreasing the predictive strength of the model. Methods Data for 637 malignant breast cancer patients admitted in the south-east region of Sweden were analyzed. By using CCA and looking at the structure coefficients (loadings), relationships between tumor specifications and the two outcomes during different time intervals were analyzed and a correlation model was built. Results The analysis successfully detected known predictors for breast cancer recurrence during the first two years and distant metastasis 2–4 years after diagnosis. Nottingham Histologic Grading (NHG) was the most important predictor, while age of the patient at the time of diagnosis was not an important predictor. Conclusion In cancer registers with high dimensionality, CCA can be used for identifying the importance of risk factors for breast cancer recurrence. This technique can result in a model ready for further processing by data mining methods through reducing the number of variables to important ones.

Background: Subgroups of breast cancer that have an impaired response to endocrine treatment, despite hormone receptor positivity, are still poorly defined. Breast cancer can be subdivided according to standard pathological parameters including histological type, grade, and assessment of proliferation. These parameters are the net result of combinations of genetic alterations effecting tumour behaviour and could potentially reflect subtypes that respond differently to endocrine treatment. Aims: To investigate the usefulness of these parameters as predictors of the response to tamoxifen in premenopausal women with breast cancer. Materials/methods: Clinically established pathological parameters were assessed and related to the tamoxifen response in 500 available tumour specimens from 564 premenopausal patients with breast cancer randomised to either two years of tamoxifen or no treatment with 14 years of follow up. Proliferation was further evaluated by immunohistochemical Ki-67 expression. Results: Oestrogen receptor positive ductal carcinomas responded as expected to tamoxifen, whereas the difference in recurrence free survival between control and tamoxifen treated patients was less apparent in the relatively few lobular carcinomas. For histological grade, there was no obvious difference in treatment response between the groups. The relation between proliferation and tamoxifen response seemed to be more complex, with a clear response in tumours with high and low proliferation, whereas tumours with intermediate proliferation defined by Ki-67 responded more poorly. Conclusions: Clinically established pathology parameters seem to mirror the endocrine treatment response and could potentially be valuable in future treatment decisions for patients with breast cancer.

PurposeVascular endothelial growth factor A (VEGF-A) and vascular endothelial growth factor receptor 2 (VEGFR2) are often coexpressed in breast cancer, and potentially affect cellular pathways and key proteins such as the estrogen receptor (ER) targeted by endocrine treatment. We therefore explored the association between adjuvant tamoxifen treatment in breast cancer and expression of VEGF-A and VEGFR2, as well as human epidermal growth factor receptor 2 (HER2), which represents a candidate gene product involved in tamoxifen resistance.Patients and MethodsImmunohistochemical expression of tumor-specific VEGF-A, VEGFR2, and HER2 was evaluated in tumor specimens from premenopausal breast cancer patients randomly assigned to 2 years of tamoxifen or no treatment (n = 564), with 14 years of follow-up. Hormone receptor status was determined in 96% of the tumors.ResultsVEGF-A, VEGFR2, and HER2 were assessable in 460, 472, and 428 of the tumors, respectively. In patients with ER-positive and VEGFR2-low tumors, adjuvant tamoxifen significantly increased recurrence-free survival (RFS; [HR] hazard ratio for RFS, 0.53; P =.001). In contrast, tamoxifen treatment had no effect in patients with VEGFR2-high tumors (HR for RFS, 2.44; P =.2). When multivariate interaction analyses were used, this difference in treatment efficacy relative to VEGFR2 expression status was statistically significant for both ER-positive (P =.04) plus ER-positive and progesterone receptor-positive tumors. We found no significant difference in tamoxifen treatment effects in relation to VEGF-A or HER2 status.ConclusionTumor-specific expression of VEGFR2 was associated with an impaired tamoxifen effect in hormone receptor-positive premenopausal breast cancer. Tamoxifen in combination with VEGFR2 inhibitors might be a novel treatment approach for VEGFR2-expressing breast cancer, and such a treatment might restore the tamoxifen response.

Adjuvant tamoxifen treatment increases recurrence-free survival (RFS) and overall survival (OS) in early breast cancer, although in premenopausal patients the number of studies comparing tamoxifen vs no treatment are limited. We report herein the effect on RFS of adjuvant tamoxifen treatment in a multicentre trial of premenopausal patients with stage II breast cancer patients randomised between 1986 and 1991 to 2 years of tamoxifen treatment (n=276) or no treatment (n=288). The receptor status of the tumour was known for 541 (96%) of the patients included. Tamoxifen treatment significantly increased RFS in patients with hormone receptor-positive (oestrogen receptor-positive (ER+) and/or progesterone receptor-positive (PR+)) tumours (Relative Risk (RR) 0.65; 95% Confidence Interval (CI): 0.48–0.89, P=0.006), and the beneficial effect of tamoxifen was extended to patients with indicators of poor prognosis, such as young age and nodal-positivity. PR status was a significant predictor of response to tamoxifen in multivariate models with testing of interactions of hormone receptor status and adjuvant therapy.

Aims: To evaluate aspects of the current practice of sentinel lymph node (SLN) pathology in breast cancer via a questionnaire based survey, to recognise major issues that the European guidelines for mammography screening should address in the next revision. Methods: A questionnaire was circulated by mail or electronically by the authors in their respective countries. Replies from pathology units dealing with SLN specimens were evaluated further. Results: Of the 382 respondents, 240 European pathology units were dealing with SLN specimens. Sixty per cent of these units carried out intraoperative assessment, most commonly consisting of frozen sections. Most units slice larger SLNs into pieces and only 12% assess these slices on a single haematoxylin and eosin (HE) stained slide. Seventy one per cent of the units routinely use immunohistochemistry in all cases negative by HE. The terms micrometastasis, submicrometastasis, and isolated tumour cells (ITCs) are used in 93%, 22%, and 71% of units, respectively, but have a rather heterogeneous interpretation. Molecular SLN staging was reported by only 10 units (4%). Most institutions have their own guidelines for SLN processing, but some countries also have well recognised national guidelines. Conclusions: Pathological examination of SLNs throughout Europe varies considerably and is not standardised. The European guidelines should focus on standardising examination. They should recommend techniques that identify metastases > 2 mm as a minimum standard. Uniform reporting of additional findings may also be important, because micrometastases and ITCs may in the future be shown to have clinical relevance.