Conformal Preoperative Endorectal Brachytherapy Treatment for Locally Advanced Rectal Cancer

Vuong, T.; Belliveau, Paul; Michel, René P.; Moftah, Belal; Parent, Josée; Trudel, Judith L.; Reinhold, Caroline; Souhami, Luís

doi:10.1007/s10350-004-6455-y

Cited by 89 publications

(51 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…12 Serial sections were cut at 3 mm and immunohistochemistry by the avidinbiotin complex (ABC) procedure, including heat-induced epitope retrieval, was undertaken. Incubation with the primary antibody was carried out in a moist chamber for 1 h at 371C for p53 (DAKO, clone DO-7, Denmark, 1:100) and at room temperature for VEGF (Santa Cruz Biotechnology, VEGF-A20, USA, 1:100) and APAF-1 (Novocastra, NCL-APAF-1, 1:40).…”

Section: Methodsmentioning

confidence: 99%

Scoring of p53, VEGF, Bcl-2 and APAF-1 immunohistochemistry and interobserver reliability in colorectal cancer

et al. 2006

View full text Add to dashboard Cite

Molecular tumor markers are often studied in colorectal cancer using immunohistochemistry to determine their prognostic or predictive value. Protein expression is typically assigned a 'positive' score based on a predetermined cutoff. A semiquantitative scoring method that evaluates the percentage of positive tumor cells (0-100%) may provide a better understanding of the prognostic or predictive significance of these markers. The aim of this study was to assess and compare the interobserver agreement of immunohistochemistry scores using a percentage scoring method and three categorical scoring systems. Immunohistochemistry for p53, Bcl-2, vascular endothelial growth factor (VEGF) and apoptotic protease activating factor-1 (APAF-1) was performed on 87 tumor biopsies from patients with rectal carcinoma and scored independently by four pathologists as the percentage of positive tumor cells. Interobserver agreement was assessed by the intraclass correlation coefficient. The intraclass correlation coefficients for p53 and VEGF (40.6) indicate substantial agreement between observers. The distribution of Bcl-2 and APAF-1 scores in addition to weaker interobserver agreement by percentage scoring suggest that this approach may not be appropriate for these proteins. In conclusion, p53 and VEGF protein expression assessed by immunohistochemistry in colorectal cancer and scored as a percentage of positive tumor cells may be a viable alternative scoring method.

show abstract

Section: Methodsmentioning

confidence: 99%

Scoring of p53, VEGF, Bcl-2 and APAF-1 immunohistochemistry and interobserver reliability in colorectal cancer

et al. 2006

View full text Add to dashboard Cite

show abstract

“…This study was approved by the Institutional Review Board and informed written consent was obtained from 82 patients with rectal adenocarcinoma undergoing preoperative HDREB (Vuong et al, 2002;Vuong et al, 2005). Clinical staging according to the International Union against Cancer Classification was carried out by both endorectal ultrasonography and MRI.…”

Section: Study Groupmentioning

confidence: 99%

A simple and reproducible scoring system for EGFR in colorectal cancer: application to prognosis and prediction of response to preoperative brachytherapy

et al. 2007

View full text Add to dashboard Cite

The aim of this study was to determine the predictive and prognostic value of epidermal growth factor receptor (EGFR) expression in rectal cancers treated with preoperative high-dose rate brachytherapy and in mismatch-repair (MMR)-proficient colorectal cancers (CRCs), respectively. We validate the use of receiver operating characteristic (ROC) curve analysis to select cutoff scores for EGFR overexpression for the end points studied. Immunohistochemistry (IHC) for EGFR was performed on 82 rectal tumour biopsies and 1197 MMR-proficient CRCs using a tissue microarray. Immunoreactivity was scored as the percentage of positive tumour cells by three pathologists and the inter-observer reliability was assessed. ROC curve-derived cutoffs were used to analyse the association of EGFR overexpression, tumour response and several clinicopathological features including survival. The scoring method was found to be reproducible in rectal cancer biopsies and CRCs. The selected cutoff scores from ROC curve analysis for each clinicopathological feature were highly consistent among pathologists. EGFR overexpression was associated with response to radiotherapy (P-value o0.001) and with worse survival time (P-value o0.001). In multivariate analysis, EGFR overexpression was independently associated with adverse prognosis (P-value o0.001). Epidermal growth factor receptor is a predictive marker of response to preoperative radiotherapy and an independent adverse prognostic factor CRC.

show abstract

“…Recently, short-course preoperative radiotherapy was found to decrease these rates even further in combination with total mesorectal excision (TME) (Kapiteijn et al, 2001). Short-course continuous, hyperfractionated, accelerated radiation therapy (CHART) and conformal high-dose-rate endorectal brachytherapy (HDREB) have demonstrated high rates of complete pathologic response as well as acceptable toxicity levels and tolerable side effects (Vuong et al, 2002(Vuong et al, , 2007Brooks et al, 2006). Several pathological features have been identified as prognostic factors in patients undergoing preoperative radiotherapy with or without chemotherapy.…”

mentioning

confidence: 99%

Combined analysis of VEGF and EGFR predicts complete tumour response in rectal cancer treated with preoperative radiotherapy

et al. 2008

View full text Add to dashboard Cite

The ability to predict complete pathologic response or sensitivity to radiation before treatment would have a significant impact on the selection of patients for preoperative radiotherapy or chemo-radiation therapy schedules. The aim of this study was to determine the value of epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), p53, Bcl-2 and apoptosis proteaseactivating factor-1 (APAF-1) as predictors of complete pathologic tumour regression in patients undergoing preoperative radiotherapy for advanced rectal cancer. Pretreatment tumour biopsies from predominantly cT3 patients undergoing a preoperative high-dose-rate brachytherapy protocol were immunostained for EGFR, VEGF, p53, Bcl-2 and APAF-1. Immunoreactivity was evaluated by three pathologists. Cut-off scores for tumour marker positivity were obtained by receiver-operating characteristic (ROC) curve analysis. The association of marker expression with complete pathologic response was analysed in univariate and multivariable analysis. Multi-marker phenotypes of the independent protein markers were evaluated. In multivariable analysis, loss of VEGF (P-value ¼ 0.009; odds ratio (OR) (95% CI) ¼ 0.24 (0.08 -0.69)) and positive EGFR (P-value ¼ 0.01; OR (95% CI) ¼ 3.82 (1.37 -10.6)) both demonstrated independent predictive value for complete pathologic response. The odds of complete response were 12.8 for the multi-marker combination of VEGF-negative and EGFR-positive tumours. Of the 34 EGFR-negative-and VEGFpositive cases, 32 (94.1%) had no complete pathologic response. The combined analysis of VEGF and EGFR is predictive of complete pathologic response in patients undergoing preoperative radiotherapy. In addition, the findings of this study have identified a subgroup of simultaneous EGFR-negative and VEGF-positive patients who are highly resistant to radiotherapy and should perhaps be considered candidates for innovative neoadjuvant combined modalities.

show abstract

Conformal Preoperative Endorectal Brachytherapy Treatment for Locally Advanced Rectal Cancer

Cited by 89 publications

References 42 publications

Scoring of p53, VEGF, Bcl-2 and APAF-1 immunohistochemistry and interobserver reliability in colorectal cancer

Scoring of p53, VEGF, Bcl-2 and APAF-1 immunohistochemistry and interobserver reliability in colorectal cancer

A simple and reproducible scoring system for EGFR in colorectal cancer: application to prognosis and prediction of response to preoperative brachytherapy

Combined analysis of VEGF and EGFR predicts complete tumour response in rectal cancer treated with preoperative radiotherapy

Contact Info

Product

Resources

About