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Mikael Lundin

Publications and source records attributed to Mikael Lundin.

12 recordsLinked to original sources

Generalisability of survival estimates for patients with breast cancer--a comparison across two population-based series.

The purpose of the study was to analyse the generalisability and geographic transportability of survival estimates produced by commonly used prognostic factors. We compared the influence of tumour size, histologic grade, axillary nodal status, oestrogen and progesterone receptor contents, age at diagnosis and two prognostication schemes (the Nottingham Prognostic Index and St. Gallen criteria) in two nationwide cohorts of patients diagnosed with breast cancer in 1991-2, the FinProg (n=2923, Finland) and the SEER series (n=43,249, the United States (US)). Eight-year estimates of breast cancer-specific (84% versus 80%), relative (86% versus 83%), and overall (70% versus 69%) survival were slightly more favourable in the SEER than in the FinProg series, respectively. Despite differences in demographic variables and the frequency of use of adjuvant therapies and mammography screening between the series, the prognostic factors examined produced close to overlapping survival curves with similar shapes. The results suggest that quantitative survival estimates based on frequently used prognostic factors and prognostication schemes are generalisable and transportable between large, unselected cohorts of breast cancer patients.

Adult↗

Down-regulated xanthine oxidoreductase is a feature of aggressive breast cancer.

PURPOSE: Xanthine oxidoreductase (XOR) is a key enzyme in the degradation of DNA, RNA, and high-energy phosphates and also plays a role in milk lipid globule secretion. Given the strong and regulated expression of XOR in normal breast epithelium, and the previously shown alterations of its expression in experimental tumorigenesis, we hypothesized that XOR may be differentially expressed in breast cancer. EXPERIMENTAL DESIGN: XOR expression was analyzed by immunohistochemistry in tissue microarray specimens of 1,262 breast cancer patients with a median follow-up of 9.5 years. RESULTS: Expression of XOR was moderately decreased in 50% and undetectable in another 7% of the tumors. Decreased XOR expression was associated with poor histologic grade of differentiation, ductal and lobular histologic types, large tumor size, high number of positive axillary lymph nodes, and high cyclooxygenase-2 expression, but not with estrogen or progesterone receptor status, Ki-67, p53, or ERBB2 amplification. Absence of XOR expression was associated with unfavorable outcome, and patients with no XOR expression had more than twice the risk of distant recurrence as compared with those with a moderately decreased or normal expression (hazard ratio, 2.21; P < 0.0001). This was also true in patients with node-negative disease (hazard ratio, 2.75; P < 0.0001) as well as in patients with small (< or = 1 cm) tumors (hazard ratio, 3.09; P = 0.027). In a multivariate survival analysis, negative XOR emerged as an independent prognostic factor both in the entire series (P = 0.01) and among patients with node-negative disease (P = 0.0009). CONCLUSION: Loss of XOR identifies breast cancer patients with unfavorable prognosis.

Breast↗

Cleavable ErbB4 isoform in estrogen receptor-regulated growth of breast cancer cells.

ErbB1 and ErbB2 receptors are well-characterized targets for anticancer drugs, but the clinical relevance of the related ErbB4 receptor is unknown. Here, we have assessed the clinical significance of the proteolytically cleavable ErbB4 isoforms in breast cancer patients and investigated their functions in vitro. The expression of transcripts encoding the cleavable ErbB4 isoforms associated with estrogen receptor-alpha (ER) expression (P < 0.001) and a high histologic grade of differentiation (P </= 0.002) in real-time reverse transcription-PCR analysis of 62 breast cancer samples. Despite high ErbB4 mRNA expression levels in a subset of samples, ErbB4 gene amplification was not observed. High ErbB4 protein expression levels, as assessed by immunohistochemistry, associated with a favorable outcome in ER-positive cases from a series of 458 breast cancer patients (P = 0.01), whereas no association between ErbB4 expression and survival was found among women with ER-negative cancer (P = 0.86). However, nuclear ErbB4 immunoreactivity was associated with poor survival as compared with women whose cancer had membranous ErbB4 staining (P = 0.04). In vitro, overexpression of a cleavable ErbB4 isoform in ER-positive breast cancer cells resulted in translocation of a proteolytically released intracellular ErbB4 receptor fragment into the nucleus, as well as, enhanced proliferation, anchorage-independent growth, and estrogen response element-mediated transcriptional activity. These results suggest that the association of ErbB4 expression with clinical outcome is dependent on the subcellular localization of ErbB4 and that a proteinase-cleavable ErbB4 isoform promotes growth of ER-positive breast cancer and enhances ER-mediated gene transcription.

Alternative Splicing↗

Web-based virtual microscopy in teaching and standardizing Gleason grading.

Gleason grading forms the basis of prognostic and therapeutic assessment in prostatic carcinoma despite its subjective nature and substantial interobserver variation. The accuracy of Gleason grading can be improved by the use of educational tools such as reference images. However, conventional microscopy images are of limited educational value because it is neither possible to view the sample at different magnifications nor to navigate into different areas of the specimen. This limitation can be overcome by the use of virtual microscopy, which allows viewing entire digitized microscope slides. We created an interactive Web site ( www.webmicroscope.net/gleason ) featuring a comprehensive set of prostatic needle biopsies as virtual slides, which can be viewed with a standard Web browser (Internet Explorer or Netscape). To evaluate the validity of Web-based virtual microscopy for Gleason grading, an experienced uropathologist (TK) scored a series of 62 biopsies from the original glass slides and 6 weeks later from virtual slides on the Web site using an ordinary desktop computer. The intraobserver agreement was excellent, with identical Gleason scores found in 48 of the 62 cases ( kappa = 0.73). The 14 remaining scores differed only by 1 point on the Gleason scale (2-10). The virtual slides were viewed by 2 other uropathologists (PM and HH), with interobserver kappa coefficients ranging from 0.55 to 0.62, which is within the range of previously reported studies using glass slides. The 3 uropathologists' Gleason scores were included as reference scores on the Web site, which now serves as a publicly open platform for self-testing and learning of Gleason grading. We conclude that Web-based virtual microscopy is a promising new tool for teaching and standardizing Gleason grading.

Biopsy, Needle↗

Risk for distant recurrence of breast cancer detected by mammography screening or other methods.

CONTEXT: Selection of systemic adjuvant therapies for women diagnosed as having breast cancer is based on risk estimations for cancer recurrence. In such estimations, tumors detected by mammography screening are considered to be associated with a similar risk of recurrence as tumors of similar size found by other methods. OBJECTIVE: To compare the risk of recurrence and survival among women with cancerous tumors detected by mammography screening compared with other methods (outside of screening). DESIGN, SETTING, AND PATIENTS: Retrospective study comparing clinical, histopathological, and biological features of cancerous tumors detected by mammography screening compared with tumors detected outside of screening. Women diagnosed as having breast cancer in 1991 or 1992 were identified from the Finnish Cancer Registry (n = 2842). The median follow-up time was 9.5 years. Cancer biological variables were analyzed from tumor tissue microarrays using immunohistochemistry or in situ hybridization and included ERBB2, TP53, and MK167 expression and ERBB2 amplification data. MAIN OUTCOME MEASURES: Univariate and multivariate analyses of potential risk factors for distant recurrence of breast cancer and 10-year survival. RESULTS: Of the 1983 women with unilateral invasive breast cancer, data on tumor diameter were available for 1918 women. Women with cancerous tumors detected by mammography screening had better estimated 10-year distant disease-free survival than women with tumors found outside of screening (tumor size of < or =10 mm [n = 386] 92% vs 85% [P =.04]; 11-20 mm [n = 808] 88% vs 76% [P<.001]; 21-30 mm [n = 409] 86% vs 63% [P =.008]; >30 mm [n = 315] 68% vs 50% [P =.12], respectively). In a Cox multivariate model that included cancer biological factors, the relative hazard ratio for distant recurrence among women with tumors detected outside of screening (HR, 1.90; 95% confidence interval, 1.15-3.11) was significantly higher than among women with tumors detected by mammography screening (P =.01). Breast cancer diagnosis by mammography screening was an independent prognostic variable reducing the relative HR for distant recurrence. This effect was equal to or greater than the effect of 1-cm decrease in tumor diameter (HR, 1.20; 95% confidence interval, 1.10-1.31). CONCLUSIONS: Cancerous tumors detected by mammography screening are associated with a better prognosis than tumors of similar size found outside of screening. The risk of distant metastases is overestimated for women diagnosed as having cancer by mammography screening unless the method of detection is taken into account in risk estimations.

Adult↗

Validation of a Web-based prognostic system for breast cancer.

A website has been published which allows the user to enter information on prognostic factors for a patient with breast cancer, and instantly obtain a survival curve based on outcome data of prior cases with a matching prognostic factor profile. The source for the survival data is a Finnish nationwide series (the FinProg series) of 2,842 women diagnosed with breast cancer in 1991-2. The purpose of this study was to compare survival estimates based on the FinProg database, with estimates for breast cancer patients from the US, obtained from the SEER public-use database and the same time-period. Results show that a reasonable level of agreement between estimates can be reached, by the use of large, unselected databases, and that significantly different estimates were obtained in only 2 of 19 analyzed prognostic profiles. The current system could be used to share important knowledge on outcome between researchers and clinicians at different institutions, and be used in the decision-making process concerning treatment of patients with breast cancer.

Breast Neoplasms↗

Ski-related novel protein N (SnoN), a negative controller of transforming growth factor-beta signaling, is a prognostic marker in estrogen receptor-positive breast carcinomas.

Transforming growth factor (TGF)-beta arrests the growth of breast epithelial cells, whereas breast cancer cells are highly resistant to its growth restrictive properties. To define causes for the defect in TGF-beta action, we present here the first in vivo analysis of Ski-related novel protein N (SnoN), a negative regulator of TGF-beta signaling, in human breast carcinomas. SnoN expression was analyzed by immunohistochemistry in a tissue microarray of 1122 breast carcinomas and 10 reduction mammoplasties. In the normal breast, SnoN was located predominantly in nuclei of large duct epithelial cells and the cytoplasm of terminal duct epithelial cells. Breast cancers displayed variances in both SnoN expression levels and subcellular localizations. High levels of cytoplasmic SnoN were more often observed in tumors of ductal histological type and associated with adverse prognostic features, such as lack of hormone receptors; high levels of p53, Ki-67, and cyclooxygenase-2; and amplifications of HER-2. High levels of nuclear SnoN were associated with lobular histology and favorable features, including presence of hormone receptors, low expression of p53 and Ki-67, and lack of HER-2 amplifications. Reduced expression of SnoN significantly correlated with longer distant disease-free survival in estrogen receptor-positive patients (P = 0.0027, relative risk = 3.27; 95% confidence interval = 1.44-7.41). The results suggest that the subcellular localization of SnoN may have clinical significance and that reduced expression of SnoN is associated with favorable outcome in estrogen receptor-positive breast cancer.

Adult↗

Tenascin-C expression correlates with prognosis in gastric cancer.

OBJECTIVES: Tenascin-C is a hexameric extracellular matrix glycoprotein that is expressed during embryonic development and re-expressed in proliferative processes such as wound healing and tumorigenesis. Stromal tenascin-C may block tumor invasion and thus have a significant influence on tumor spread and prognosis. METHODS: In the present study, tissue expression of stromal tenascin-C was studied by immunohistochemistry in a series of 314 patients with gastric cancer. RESULTS: Strong tenascin-C positivity was seen in the stroma of the tumor in 122 (39%) cases. There was a correlation between strong tenascin-C expression and low stage (p = 0.002), superficial tumor penetration (p = 0.02), location of tumor at the distal third of the stomach (p = 0.03), and potentially curative surgery (p = 0.008). No significant correlation was found between tenascin-C positivity and nodal status, distant metastases, age, Laurén classification, gender, tumor size, or Borrmann classification. The cumulative 5-year survival in patients with strong tenascin-C expression was 42% compared to 26% in those with negative-to-moderate expression (p = 0.0053). In multivariate survival analysis stratified for estimated cure of surgery, stage of disease was the only independent prognostic factor. CONCLUSION: In conclusion, tenascin-C expression seems to correlate with cancer related survival in patients with gastric cancer, but may not add significant prognostic information to that provided by TNM stage.

Aged↗

Amplification of erbB2 and erbB2 expression are superior to estrogen receptor status as risk factors for distant recurrence in pT1N0M0 breast cancer: a nationwide population-based study.

PURPOSE: To assess the relative importance of 10 prognostic factors in pT1N0M0 breast cancer (< or =2 cm in diameter, node negative). EXPERIMENTAL DESIGN: Women diagnosed with breast cancer in Finland from 1991 to 1992 were identified from the files of the Finnish Cancer Registry, and individual clinicopathological data were collected from the hospital case records of women living in five regions comprising about one-half of the Finnish population. Of the women with minimum required information available (n = 2842), 852 had unilateral pT(1)N(0)M(0) cancer. The median follow-up time was 9.5 years, and only 5% had received systemic adjuvant therapy. Estrogen receptor (ER), progesterone receptor, erbB2, p53, and Ki-67 expression was determined from tumor tissue microarrays using immunohistochemistry, and the erbB2 (HER-2) amplification status was determined using chromogenic in situ hybridization. RESULTS: Primary tumor size < or =5 mm and histological grade 1 were associated with 100 and 95% (95% confidence interval, 92-98%) 9-year distant disease-free survival, respectively, whereas strong erbB2 expression or the presence of >20% Ki-67-positive cells was associated with >20% risk. ER and progesterone receptor values obtained from the hospital case records or tumor microarrays showed weaker association with outcome than the erbB2 status. Small (< or =10 mm) erbB2-negative cancers were associated with >90% 9-year distant disease-free survival, irrespective of histological grade. CONCLUSIONS: Prognosis of pT(1)N(0)M(0) breast cancer is generally well defined by the histological grade and primary tumor size. The erbB2 status was superior to ER as a prognostic factor in these tumors.

Adult↗

Evaluation of a web-based system for survival estimation in breast cancer.

OBJECTIVES: To evaluate the accuracy of an internet-based method for survival estimation in breast cancer. DESIGN: A website was created which allows the user to enter information on prognostic factors for a patient, and instantly obtain a Kaplan-Meler survival curve based on outcome data of prior cases with a matching prognostic factor profile. The source for the survival data is a Finnish nationwide series of 2,842 women diagnosed with breast cancer in 1991-2, comprising 91% of all cases within the selected geographical regions during these two years. MAIN OUTCOME MEASURES: The accuracy of the survival estimates obtained using data from the nationwide series was assessed in an independent, single institution validation series (n = 565), and measured by analysis of calibration and discrimination (the area under the ROC curve). RESULTS: A selection of prognostic factors recommended by the National Institutes of Health (NIH) Consensus Development Panel and the International Consensus Panel on the Treatment of Primary Breast Cancer were made available for case-matching on the website. Kaplan-Meier case-match eight-year estimates of distant disease-free survival (DDFS) based on combinations of tumour size, histologic grade and mode of detection (screen-detected vs. symptomatic) were close to the actual outcomes, e.g. patients in the validation set who were estimated to have a 71-80%, 81-90% and 96-100% DDFS had an actual average DDFS of 76%, 88%, and 100%, respectively. CONCLUSIONS: A web-based case-match system can generate survival curves for user-defined prognostic factor combinations and identify patients with a varying risk for breast cancer recurrence. The system can be linked to other data sets, expanded to accommodate new prognostic factors and used as a source for population-based survival estimates.

Breast Neoplasms↗

Prognostic significance of elevated cyclooxygenase-2 expression in breast cancer.

Cyclooxygenase-2 (Cox-2) expression can induce mammary tumorigenesis in transgenic mice, and selective Cox-2 inhibitors are both chemopreventive and chemotherapeutic in rat models of breast cancer. We analyzed the expression of Cox-2 protein by immunohistochemistry in tissue array specimens of 1576 invasive breast cancers. Moderate to strong (elevated) expression of Cox-2 protein was observed in 37.4% of the tumors, and it was associated with unfavorable distant disease-free survival (P < 0.0001). Elevated Cox-2 expression was associated with a large tumor size, a high histological grade, a negative hormone receptor status, a high proliferation rate (identified by Ki-67), high p53 expression, and the presence of HER-2 oncogene amplification (P < 0.0001 for all comparisons), along with axillary node metastases and a ductal type of histology (P = 0.0001 and P = 0.0017, respectively). Interestingly, association with the unfavorable outcome was especially apparent in the subgroups defined by estrogen receptor positivity, low p53 expression, and no HER-2 amplification (P < 0.0001 for all comparisons). These results indicate that elevated Cox-2 expression is more common in breast cancers with poor prognostic characteristics and is associated with an unfavorable outcome. The present findings support efforts to initiate clinical trials on the efficacy of Cox-2 inhibitors in adjuvant treatment of breast cancer.

Breast Neoplasms↗