Development and evaluation of a virtual microscopy application for automated assessment of Ki-67 expression in breast cancer

<p>Abstract</p> <p>Background</p> <p>The aim of the study was to develop a virtual microscopy enabled method for assessment of Ki-67 expression and to study the prognostic value of the automated analysis in a comprehensive series of patients with breast cancer.</p> <p>Methods</p> <p>Using a previously reported virtual microscopy platform and an open source image processing tool, ImageJ, a method for assessment of immunohistochemically (IHC) stained area and intensity was created. A tissue microarray (TMA) series of breast cancer specimens from 1931 patients was immunostained for Ki-67, digitized with a whole slide scanner and uploaded to an image web server. The extent of Ki-67 staining in the tumour specimens was assessed both visually and with the image analysis algorithm. The prognostic value of the computer vision assessment of Ki-67 was evaluated by comparison of distant disease-free survival in patients with low, moderate or high expression of the protein.</p> <p>Results</p> <p>1648 evaluable image files from 1334 patients were analysed in less than two hours. Visual and automated Ki-67 extent of staining assessments showed a percentage agreement of 87% and weighted kappa value of 0.57. The hazard ratio for distant recurrence for patients with a computer determined moderate Ki-67 extent of staining was 1.77 (95% CI 1.31-2.37) and for high extent 2.34 (95% CI 1.76-3.10), compared to patients with a low extent. In multivariate survival analyses, automated assessment of Ki-67 extent of staining was retained as a significant prognostic factor.</p> <p>Conclusions</p> <p>Running high-throughput automated IHC algorithms on a virtual microscopy platform is feasible. Comparison of visual and automated assessments of Ki-67 expression shows moderate agreement. In multivariate survival analysis, the automated assessment of Ki-67 extent of staining is a significant and independent predictor of outcome in breast cancer.</p

Tamoxifen for prevention of breast cancer: extended long-term follow-up of the IBIS-I breast cancer prevention trial

© Cuzick et al. Open Access article distributed under the terms of CC BY.http://dx.doi.org/10.1016/S1470-2045(14)71171-

Breast cancer biological subtypes and protein expression predict for the preferential distant metastasis sites: a nationwide cohort study

Introduction Some molecular subtypes of breast cancer have preferential sites of distant relapse. The protein expression pattern of the primary tumor may influence the first distant metastasis site. Methods We identified from the files of the Finnish Cancer Registry patients diagnosed with breast cancer in five geographical regions Finland in 1991-1992, reviewed the hospital case records, and collected primary tumor tissue. Out of the 2,032 cases identified, 234 developed distant metastases after a median follow-up time of 2.7 years and had the first metastatic site documented (a total of 321 sites). Primary tumor microarray (TMA) cores were analyzed for 17 proteins using immunohistochemistry and for erbB2 using chromogenic in situ hybridization, and their associations with the first metastasis site were examined. The cancers were classified into luminal A, luminal B, HER2+ enriched, basal-like or non-expressor subtypes. Results A total of 3,886 TMA cores were analyzed. Luminal A cancers had a propensity to give rise first to bone metastases, HER2-enriched cancers to liver and lung metastases, and basal type cancers to liver and brain metastases. Primary tumors that gave first rise to bone metastases expressed frequently estrogen receptor (ER) and SNAI1 (SNAIL) and rarely COX2 and HER2, tumors with first metastases in the liver expressed infrequently SNAI1, those with lung metastases expressed frequently the epidermal growth factor receptor (EGFR), cytokeratin-5 (CK5) and HER2, and infrequently progesterone receptor (PgR), tumors with early skin metastases expressed infrequently E-cadherin, and breast tumors with first metastases in the brain expressed nestin, prominin-1 and CK5 and infrequently ER and PgR. Conclusions Breast tumor biological subtypes have a tendency to give rise to first distant metastases at certain body sites. Several primary tumor proteins were associated with homing of breast cancer cells.BioMed Central Open acces

Long-term prognosis of breast cancer detected by mammography screening or other methods

Introduction Previous studies on breast cancer have shown that patients whose tumors are detected by mammography screening have a more favorable survival. However, little is known about the long-term prognostic impact of screen-detection. The purpose of the current study was to compare breast cancer-specific long-term survival between patients whose tumors were detected in mammography screening and those detected by other methods. Methods Breast cancer patients diagnosed within five specified geographical areas in Finland in 1991-92 were identified (n=2,936). Detailed clinical, treatment and outcome data as well as tissue samples were collected. Women with in situ carcinoma, distant metastases at the primary diagnosis and women who were not operated were excluded. Main analyses were made with exclusions of patients with other malignancy or contralateral breast cancer followed by to sensitivity analyses with different exclusion criterias. Median follow-up time was 15.4 years. Univariate and multivariate analysis of breast cancer-specific survival were performed. Results Of patients included in the main analyses (n=1,884) 22% (n=408) were screen-detected and 78% (n=1,476) were detected by other methods. Breast cancer-specific 15-year survival was 86% for patients with screen-detected cancer and 66% for patients diagnosed by other methods (p<0.0001, HR=2.91). Similar differences in survival were also observed in women at screening age (50-69 years) as well as in clinically important subgroups, such as patients with small tumors ([less than or equal to]1cm in diameter) and without nodal involvement (N0). Women with breast cancer diagnosed by screening mammography had a more favorable prognosis compared to those diagnosed outside of screening program following adjustments according to patient age, tumor size, axillary lymph node status, histological grade and hormone receptor status. Significant differences in the risk of having future contralateral breast cancer according to method of detection was not observed . Conclusions Breast cancer detection in mammography screening is an independent prognostic factor in breast cancer and is associated with a more favorable survival also in long-term follow-up.BioMed Central open acces

Tamoxifen for prevention of breast cancer: extended long-term follow-up of the IBIS-I breast cancer prevention trial. Lancet Oncol

Summary Background Four previously published randomised clinical trials have shown that tamoxifen can reduce the risk of breast cancer in healthy women at increased risk of breast cancer in the first 10 years of follow-up. We report the long-term follow-up of the IBIS-I trial, in which the participants and investigators remain largely masked to treatment allocation