Georg Pfeiler

Dr. Georg Pfeiler


Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 September 2013 in British Journal of Cancer
Verified
Journal Article
Open access
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GPGeorg Pfeiler
Georg Pfeiler
RKR Königsberg
R Königsberg
PHP Hadji
P Hadji
FFF Fitzal
F Fitzal
MMM Maroske
M Maroske
PDP Dubsky
P Dubsky
Body mass index (BMI) has an impact on survival outcome in patients treated with aromatase inhibitors (AIs). Obesity is associated with an increased body aromatisation and may be a cause of insufficient estradiol depletion. Sixty-eight postmenopausal oestrogen receptor-positive patients with early breast cancer were prospectively included in this study. Follicle stimulating hormone (FSH), luteinizing hormone (LH) and estradiol were analysed immediately in the clinical routine lab and in a dedicated central lab before (T1) and 3 months after start with aromatase inhibitors (T2). A total of 40 patients were normal or overweight (non-obese: BMI 18.5–29.9 kg m−2) and 28 were obese (BMI30 kg m−2). Aromatase inhibitors significantly suppressed estradiol serum levels (T1: 19.5 pg ml−1, T2: 10.5 pg ml−1, P<0.01) and increased FSH serum levels (T1: 70.2 mIU ml−1, T2: 75.7 mIU ml−1, P<0.05). However, after 3 months of AI treatment, estradiol levels of obese patients were nonsignificantly higher compared with non-obese patients (12.5 pg ml−1 vs 9.0 pg ml−1, P=0.1). This difference was reflected by significantly lower FSH serum levels in obese compared with non-obese patients (65.5 mIU ml−1 vs 84.6 mIU ml−1, P<0.01). The significant effects of BMI on FSH serum levels could be detected both in the routine as well as in the dedicated central lab. Aromatase inhibitors are less efficient at suppressing estradiol serum levels in obese when compared with non-obese women.

8 July 2016 in BMC Cancer
Verified
Journal Article
Open access
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CSChristine Staudigl
Christine Staudigl
GPGeorg Pfeiler
Georg Pfeiler
KHKatharina Hrauda
Katharina Hrauda
RRRomana Renz
Romana Renz
ABAndreas Berger
Andreas Berger
MTMuy-Kheng M. Tea
Muy-Kheng M. Tea
The purpose of this study was to evaluate socio-demographic characteristics of clients claiming genetic counseling for hereditary breast and ovarian cancer (HBOC) in Austria. Furthermore, changes of these parameters before and after Angelina Jolie’s (AJ) disclosure of carrying a BRCA mutation were evaluated. In this prospective, nonrandomized study 268 consecutive clients seeking genetic counseling for HBOC at the Medical University of Vienna, Department of Obstetrics and Gynecology, Vienna, Austria between June 2012 and June 2014 were included. Socio-demographic data and source of information about HBOC and genetic counseling were evaluated. First, socio-demographic parameters were compared to the general Austrian population. Second, changes in these parameters after AJ’s public disclosure of carrying a BRCA mutation were analyzed. Subjects were more frequent female, younger and higher educated in comparison to Austria’s general population (p < 0.001). Furthermore, level of education in participants was higher before than after AJ’s disclosure (p = 0.046). Most clients were informed about genetic counseling by physicians. As expected, after AJ’s public announcement patients were more frequent advised to genetic counseling by social media (p = 0.043) and family or friends (p = 0.010) than before. In this present study we could demonstrate that particularly younger and female participants with high educational level attended significantly more often genetic counseling for HBOC. Increased presence of HBOC in media since AJ’s disclosure of carrying a BRCA mutation had lead that information and awareness about HBOC was obtained by a wider audience from different social background.

20 October 2009 in Breast Cancer Research
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Journal Article
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SNSusan L Neuhausen
Susan L Neuhausen
SBSean Brummel
Sean Brummel
YDYuan Chun Ding
Yuan Chun Ding
Christian SingerChristian Singer
Christian Singer
GPGeorg Pfeiler
Georg Pfeiler
DGDaniel L Gillen
Daniel L Gillen
Introduction: Women who carry mutations in BRCA1 and BRCA2 have a substantially increased risk of developing breast cancer as compared with the general population. However, risk estimates range from 20 to 80%, suggesting the presence of genetic and/or environmental risk modifiers. Based on extensive in vivo and in vitro studies, one important pathway for breast cancer pathogenesis may be the insulin-like growth factor (IGF) signaling pathway, which regulates both cellular proliferation and apoptosis. BRCA1 has been shown to directly interact with IGF signaling such that variants in this pathway may modify risk of cancer in women carrying BRCA mutations. In this study, we investigate the association of variants in genes involved in IGF signaling and risk of breast cancer in women who carry deleterious BRCA1 and BRCA2 mutations. Methods: A cohort of 1,665 adult, female mutation carriers, including 1,122 BRCA1 carriers (433 cases) and 543 BRCA2 carriers (238 cases) were genotyped for SNPs in IGF1, IGF1 receptor (IGF1R), IGF1 binding protein (IGFBP1, IGFBP2, IGFBP5), and IGF receptor substrate 1 (IRS1). Cox proportional hazards regression was used to model time from birth to diagnosis of breast cancer for BRCA1 and BRCA2 carriers separately. For linkage disequilibrium (LD) blocks with multiple SNPs, an additive genetic model was assumed; and for single SNP analyses, no additivity assumptions were made. Results: Among BRCA1 carriers, significant associations were found between risk of breast cancer and LD blocks in IGF1R (global P = 0.011 for LD block 2 and global P = 0.012 for LD block 11). Among BRCA2 carriers, an LD block in IGFBP2 (global P = 0.0145) was found to be associated with the time to breast cancer diagnosis. No significant LD block associations were found for the other investigated genes among BRCA1 and BRCA2 carriers. Conclusions: This is the first study to investigate the role of genetic variation in IGF signaling and breast cancer risk in women carrying deleterious mutations in BRCA1 and BRCA2. We identified significant associations in variants in IGF1R and IRS1 in BRCA1 carriers and in IGFBP2 in BRCA2 carriers. Although there is known to be interaction of BRCA1 and IGF signaling, further replication and identification of causal mechanisms are needed to better understand these associations.

14 September 2015 in Breast Cancer Research
Verified
Journal Article
Open access
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MSMelanie Spitzwieser
Melanie Spitzwieser
EHElisabeth Holzweber
Elisabeth Holzweber
GPGeorg Pfeiler
Georg Pfeiler
SHStefan Hacker
Stefan Hacker
MCMargit Cichna-Markl
Margit Cichna-Markl
It has been shown in some articles that genetic and epigenetic abnormalities cannot only be found in tumor tissues but also in adjacent regions that appear histologically normal. This phenomenon is metaphorically called field cancerization or field defect. Field cancerization is regarded as clinically significant because it is assumed to be an important factor in local recurrence of cancer. As the field showing these molecular abnormalities may not be removed completely by surgery, these changes might lead to neoplasms and subsequent transformation to a tumor. We aimed to investigate the applicability of the methylation status of six tumor suppressor genes as biomarkers for detecting field cancerization in breast cancer. The promoter methylation status of CCND2, DAPK1, GSTP1, HIN-1, MGMT and RASSF1A was determined by methylation-sensitive high-resolution melting (MS-HRM) analysis. MS-HRM methods for CCND2, MGMT and RASSF1A were developed in-house, primer sequences for DAPK1, GSTP1 and HIN-1 have already been published. Biopsy samples were taken from tumor, tumor-adjacent and tumor-distant tissue from 17 breast cancer patients. Normal breast tissues of four healthy women served as controls. All MS-HRM methods proved to be very sensitive. LODs were in the range from 0.1 to 1.5 %, LOQs ranged from 0.3 to 5.3 %. A total of 94 %, 82 % and 65 % of the tumors showed methylation of RASSF1A, HIN-1 and MGMT promoters, respectively. The methylation status of these promoters was significantly lower in tumor-distant tissues than in tumor tissues. Tumor-adjacent tissues showed higher methylation status of RASSF1A, HIN-1 and MGMT promoters than tumor-distant tissues, indicating field cancerization. The methylation status of the HIN-1 promoter in tumor-adjacent tissues was found to correlate strongly with that in the corresponding tumors (r = 0.785, p < 0.001), but not with that in the corresponding tumor-distant tissues (r = 0.312, p = 0.239). Among the gene promoters investigated, the methylation status of the HIN-1 promoter can be considered the best suitable biomarker for detecting field cancerization. Further investigation is needed to test whether it can be used for defining surgical margins in order to prevent future recurrence of breast cancer.

20 November 2023 in Journal of Clinical Oncology
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Journal Article
Closed access
GPGeorg Pfeiler
Georg Pfeiler
DHDominik Hlauschek
Dominik Hlauschek
EMErica L. Mayer
Erica L. Mayer
CDChristine Deutschmann
Christine Deutschmann
SKStephanie Kacerovsky-Strobl
Stephanie Kacerovsky-Strobl
NWNorman Wolmark
Norman Wolmark
PURPOSE: BMI affects breast cancer risk and prognosis. In contrast to cytotoxic chemotherapy, CDK4/6 inhibitors are given at a fixed dose, irrespective of BMI or weight. This preplanned analysis of the global randomized PALLAS trial investigates the impact of BMI on the side-effect profile, treatment adherence, and efficacy of palbociclib. METHODS: Patients were categorized at baseline according to WHO BMI categories. Neutropenia rates were assessed with univariable and multivariable logistic regression. Time to early discontinuation of palbociclib was analyzed with Fine and Gray competing risk models. Unstratified Cox models were used to investigate the association between BMI category and time to invasive disease-free survival (iDFS). 95% CIs were derived. RESULTS: Of 5,698 patients included in this analysis, 68 (1.2%) were underweight, 2,082 (36.5%) normal weight, 1,818 (31.9%) overweight, and 1,730 (30.4%) obese at baseline. In the palbociclib arm, higher BMI was associated with a significant decrease in neutropenia (unadjusted odds ratio for 1-unit change, 0.93; 95% CI, 0.91 to 0.94; adjusted for age, race ethnicity, region, chemotherapy use, and Eastern Cooperative Oncology Group at baseline, 0.93; 95% CI, 0.92 to 0.95). This translated into a significant decrease in treatment discontinuation rate with higher BMI (adjusted hazard ratio [HR] for 10-unit change, 0.75; 95% CI, 0.67 to 0.83). There was no significant improvement in iDFS with the addition of palbociclib to ET in any weight category (normal weight HR, 0.84; 95% CI, 0.63 to 1.12; overweight HR, 1.10; 95% CI, 0.82 to 1.49; and obese HR, 0.95; 95% CI, 0.69 to 1.30) in this analysis early in follow-up (31 months). CONCLUSION: This preplanned analysis of the PALLAS trial demonstrates a significant impact of BMI on side effects, dose reductions, early treatment discontinuation, and relative dose intensity. Additional long-term follow-up will further evaluate whether BMI ultimately affects outcome.

12 April 2017 in BMC Cancer
Verified
Journal Article
Open access
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MSMelanie Spitzwieser
Melanie Spitzwieser
EEElisabeth Entfellner
Elisabeth Entfellner
BWBettina Werner
Bettina Werner
WPWalter Pulverer
Walter Pulverer
GPGeorg Pfeiler
Georg Pfeiler
MCMargit Cichna-Markl
Margit Cichna-Markl
Breast carcinogenesis is a multistep process involving genetic and epigenetic changes. Tumor tissues are frequently characterized by gene-specific hypermethylation and global DNA hypomethylation. Aberrant DNA methylation levels have, however, not only been found in tumors, but also in tumor-surrounding tissue appearing histologically normal. This phenomenon is called field cancerization. Knowledge of the existence of a cancer field and its spread are of clinical relevance. If the tissue showing pre-neoplastic lesions is not removed by surgery, it may develop into invasive carcinoma. We investigated the prevalence of gene-specific and global DNA methylation changes in tumor-adjacent and tumor-distant tissues in comparison to tumor tissues from the same breast cancer patients (n = 18) and normal breast tissues from healthy women (n = 4). Methylation-sensitive high resolution melting (MS-HRM) analysis was applied to determine methylation levels in the promoters of APC, BRCA1, CDKN2A (p16), ESR1, HER2/neu and PTEN, in CDKN2A exon 2 and in LINE-1, as indicator for the global DNA methylation extent. The methylation status of the ESR2 promoter was determined by pyrosequencing. Tumor-adjacent and tumor-distant tissues frequently showed pre-neoplastic gene-specific and global DNA methylation changes. The APC promoter (p = 0.003) and exon 2 of CDKN2A (p < 0.001) were significantly higher methylated in tumors than in normal breast tissues from healthy women. For both regions, significant differences were also found between tumor and tumor-adjacent tissues (p = 0.001 and p < 0.001, respectively) and tumor and tumor-distant tissues (p = 0.001 and p < 0.001, respectively) from breast cancer patients. In addition, tumor-adjacent (p = 0.002) and tumor-distant tissues (p = 0.005) showed significantly higher methylation levels of CDKN2A exon 2 than normal breast tissues serving as control. Significant correlations were found between the proliferative activity and the methylation status of CDKN2A exon 2 in tumor (r = −0.485, p = 0.041) and tumor-distant tissues (r = −0.498, p = 0.036). From our results we can conclude that methylation changes in CDKN2A exon 2 are associated with breast carcinogenesis. Further investigations are, however, necessary to confirm that hypermethylation of CDKN2A exon 2 is associated with tumor proliferative activity.