Prognostic significance of postchemoradiation stage following preoperative chemotherapy and radiation for advanced/recurrent rectal cancers

Gut microbiota-mediated nucleotide synthesis attenuates the response to neoadjuvant chemoradiotherapy in rectal cancer

Preoperative neoadjuvant chemoradiotherapy (nCRT) is a standard treatment for locally advanced rectal cancer (LARC) patients, yet little is known about the mediators underlying the heterogeneous patient response. In this longitudinal study, we performed 16S rRNA sequencing on 353 fecal specimens and find reduced microbial diversity after nCRT. Multi-omics data integration reveals that Bacteroides vulgatus-mediated nucleotide biosynthesis associates with nCRT resistance in LARC patients, and nonresponsive tumors are characterized by the upregulation of genes related to DNA repair and nucleoside transport. Nucleosides supplementation or B. vulgatus gavage protects cancer cells from the 5-fluorouracil or irradiation treatment. An analysis of 2,205 serum samples from 735 patients suggests that uric acid is a potential prognosis marker for LARC patients receiving nCRT. Our data unravel the role of intestinal microbiota-mediated nucleotide biosynthesis in the response of rectal tumors to nCRT, and highlight the importance of deciphering the cross-talk between cancer cells and gut microorganisms during cancer therapies.

Association Between Pathological Complete Response and Tumor Location in Patients with Rectal Cancer After Neoadjuvant Chemoradiotherapy, a Prospective Cohort Study

Background: Colorectal cancers are the third common malignancies after lung and breast neoplasms. Some contributing factors for pathological complete response (pCR) to neoadjuvant therapy of rectal cancer have been defined. Despite various studies in this era, there are few studies on the location of tumors. Objectives: Regarding the high prevalence of colorectal cancer in Iran and the importance of neoadjuvant chemoradiation for survival and morbidity, this study was carried out to determine the association between pathologic complete response and tumor location in patients with rectal cancer after neoadjuvant chemoradiotherapy. Methods: In this prospective cohort, 100 cases with rectal adenocarcinoma from 2017 to 2019 were enrolled. Distance between anal verge and tumor was measured by clinical examination, colonoscopy, endo-sonography, and MRI. Tumors were defined as distal (less than 5 cm from the anal verge) and none distal (more than 5 cm from the anal verge). Another subdivision was inferior (0 - 4.99 cm), middle (5 - 9.99 cm), and superior (10 - 15 cm). The pathological response was compared across the groups. Results: In this study, the pCR was seen in 30%. In univariate analysis body mass index (BMI), grade, N-stage, and distance from anal verge were related to pCR. In cases with BMI over 25 kg/m2 and in tumors with low to medium grade N0/N1, and distance less than 5 cm from the anal verge (low lying tumors) the pCR to neoadjuvant treatment was higher. In multivariate analysis tumor grade, N stage, and distance from anal verge were still related to pCR. Conclusions: According to the obtained results in this study, there may be some association between rectal tumor location and pathologic complete response.

Can normalized carcinoembryonic antigen following neoadjuvant chemoradiation predict tumour recurrence after curative resection for locally advanced rectal cancer?

AIM

The aim of this work was to evaluate whether normalized carcinoembryonic antigen (CEA) following neoadjuvant chemoradiation predicts the prognosis following curative resection in locally advanced rectal cancer.

METHOD

Patients who underwent neoadjuvant chemoradiation and curative resection for locally advanced rectal cancer between 2010 and 2015 were divided into three groups: Group A (n = 119, normal-to-normal): normal CEA before and after neoadjuvant chemoradiation; Group B (n = 37, high-to-normal): elevated CEA before and normal CEA after neoadjuvant chemoradiation; Group C (n = 36, high-to-high): elevated CEA before and after neoadjuvant chemoradiation. Overall and disease-free survival were compared. Univariate and multivariate analyses identified potential predictors for recurrence.

RESULTS

One hundred and ninety two patients [median age 59 years (range 31-87), 65.1% male] were identified: 54.7% had low rectal cancer: 12.5% were clinical stage T4 and 70.3% were clinically node positive; 21.9% achieved complete pathological response; 24.5% had abdominoperineal resection (APR); and 70.3% underwent adjuvant chemotherapy following curative resection. Significantly more patients in Group C underwent APR (p = 0.0209), had advanced pathological T stage (P = 0.0065) and a higher prevalence of perineural invasion (p = 0.0042). Overall and disease-free survival were significantly higher for Group A than for Group C [hazard ratio (HR) = 4.32, 95% CI = 1.66-11.21, p = 0.0026 and HR=2.68, 95% CI = 1.33-5.40, p = 0.0057, respectively]. No significant difference was noted between Groups A and B for overall (p = 0.0591) or disease-free (p = 0.2834) survival. Another risk factor associated with recurrence and death was clinical T4 stage; nodal positivity was a risk factor only for recurrence.

CONCLUSION

Elevated CEA after neoadjuvant chemoradiation and clinical stage T4 disease were unfavourable predictors for overall and disease-free survival. Normalized CEA during neoadjuvant chemoradiation may serve as a prognosticator, although pretreatment CEA may significantly affect survival.

Can Pre-Treatment Inflammatory Parameters Predict the Probability of Sphincter-Preserving Surgery in Patients with Locally Advanced Low-Lying Rectal Cancer?

There is evidence suggesting that pre-treatment clinical parameters can predict the probability of sphincter-preserving surgery in rectal cancer; however, to date, data on the predictive role of inflammatory parameters on the sphincter-preservation rate are not available. The aim of the present cohort study was to investigate the association between inflammation-based parameters and the sphincter-preserving surgery rate in patients with low-lying locally advanced rectal cancer (LARC). A total of 848 patients with LARC undergoing radiotherapy from 2004 to 2019 were retrospectively reviewed in order to identify patients with rectal cancer localized ≤6 cm from the anal verge, treated with neo-adjuvant radiochemotherapy (nRCT) and subsequent surgery. Univariable and multivariable analyses were used to investigate the role of pre-treatment inflammatory parameters, including the C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) for the prediction of sphincter preservation. A total of 363 patients met the inclusion criteria; among them, 210 patients (57.9%) underwent sphincter-preserving surgery, and in 153 patients (42.1%), an abdominoperineal rectum resection was performed. Univariable analysis showed a significant association of the pre-treatment CRP value (OR = 2.548, 95% CI: 1.584–4.097, p < 0.001) with sphincter preservation, whereas the pre-treatment NLR (OR = 1.098, 95% CI: 0.976–1.235, p = 0.120) and PLR (OR = 1.002, 95% CI: 1.000–1.005, p = 0.062) were not significantly associated with the type of surgery. In multivariable analysis, the pre-treatment CRP value (OR = 2.544; 95% CI: 1.314–4.926; p = 0.006) was identified as an independent predictive factor for sphincter-preserving surgery. The findings of the present study suggest that the pre-treatment CRP value represents an independent parameter predicting the probability of sphincter-preserving surgery in patients with low-lying LARC.

Predictive value of changes in the level of carbohydrate antigen 19-9 in patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy

AIM

The aim of this work was to explore the predictive value of changes in the level of carbohydrate antigen 19-9 (CA19-9) after neoadjuvant chemoradiotherapy (nCRT) and after surgery in patients with locally advanced rectal cancer (LARC).

METHOD

Patients with LARC who underwent nCRT and radical surgery (between 2011 and 2016) were divided into three groups according to pre-nCRT and post-nCRT CA19-9 levels as follows: normal pre-nCRT CA19-9 (normal CA19-9 group), elevated pre-nCRT and normal post-nCRT CA19-9 (normalized group) and elevated pre-nCRT and elevated post-nCRT CA19-9 (nonnormalized group). The pathological nCRT response criteria included ypCR and downstaging (ypStages 0-I). Recurrence-free survival (RFS) and overall survival (OS) were analysed.

RESULTS

A total of 721 patients were identified. The normal CA19-9 group was significantly associated with ypCR (n = 159) and downstaging (n = 347) (P < 0.05). The normalized group (n = 76) had worse RFS and OS than the normal CA19-9 group (n = 622) and better RFS and OS than the nonnormalized group (n = 23) (5-year RFS 47.0% vs 66.9% vs 81.5%, P < 0.001; 5-year OS 47.0% vs 75.4% vs 85.0%, P < 0.001). In multivariate analysis, CA19-9 group and ypTNM stage were independent predictors of RFS and OS. Moreover, for the 23 patients with elevated post-nCRT CA19-9 levels, the RFS and OS of patients with normalized postoperative CA19-9 levels were significantly better than those of patients with elevated postoperative CA19-9 levels (P < 0.05).

CONCLUSION

Following nCRT, changes in the CA19-9 level are a strong prognostic marker for long-term survival, and they may be helpful in the selection of patients who prefer more conservative surgery after chemoradiotherapy.

Pre-Existing Tumoral B Cell Infiltration and Impaired Genome Maintenance Correlate with Response to Chemoradiotherapy in Locally Advanced Rectal Cancer

Locally advanced rectal cancer (LARC) remains a medical challenge. Reliable biomarkers to predict which patients will significantly respond to neoadjuvant chemoradiotherapy (nCRT) have not been identified. We evaluated baseline genomic and transcriptomic features to detect differences that may help predict response to nCRT. Eligible LARC patients received nCRT (3D-LCRT 50.4 Gy plus capecitabine 825 mg/m2/bid), preceded by three cycles of CAPOX in high systemic-relapse risk tumors, and subsequent surgery. Frozen tumor biopsies at diagnosis were sequenced using a colorectal cancer panel. Transcriptomic data was used for pathway and cell deconvolution inferential algorithms, coupled with immunohistochemical validation. Clinical and molecular data were analyzed according to nCRT outcome. Pathways related to DNA repair and proliferation (p < 0.005), and co-occurrence of RAS and TP53 mutations (p = 0.001) were associated with poor response. Enrichment of expression signatures related to enhanced immune response, particularly B cells and interferon signaling (p < 0.005), was detected in good responders. Immunohistochemical analysis of CD20+ cells validated the association of good response with B cell infiltration (p = 0.047). Findings indicate that the presence of B cells is associated with successful tumor regression following nCRT in LARC. The prevalence of simultaneous RAS and TP53 mutations along with a proficient DNA repair system that may counteract chemoradio-induced DNA damage was associated with poor response.

Clinical parameters predictive for sphincter-preserving surgery and prognostic outcome in patients with locally advanced low rectal cancer

Background

Although controversial, there are data suggesting that clinical parameters can predict the probability of sphincter preserving procedures in rectal cancer. The purpose of this study was to investigate the association between clinical parameters and the sphincter-preserving surgery rate in patients who had undergone neoadjuvant combination therapy for advanced low rectal cancer.

Methods

In this single center study, the charts of 540 patients with locally advanced rectal cancer who had been treated with induction chemotherapy-and/or neoadjuvant concomitant radiochemotherapy (nRCT) over an 11-year period were reviewed in order to identify patients with rectal cancer ≤6 cm from the anal verge, who had received the prescribed nRCT only. Univariate and multivariate analyses were used to identify pretreatment patient- and tumor associated parameters correlating with sphincter preservation. Survival rates were calculated using Kaplan-Meier analyses.

Results

Two hundred eighty of the 540 patients met the selection criteria. Of the 280 patients included in the study, 158 (56.4%) underwent sphincter-preserving surgery. One hundred sixty-four of 280 patients (58.6%) had a downsizing of the primary tumor (ypT < cT) and 39 (23.8%) of these showed a complete histopathological response (ypT0 ypN0). In univariate analysis, age prior to treatment, Karnofsky performance status, clinical T-size, relative lymphocyte value, CRP value, and interval between nRCT and surgery, were significantly associated with sphincter-preserving surgery. In multivariate analysis, age (hazard ratio (HR) = 1.05, CI95%: 1.02–1.09, p = 0.003), relative lymphocyte value (HR = 0.94, CI95%: 0.89–0.99, p = 0.029), and interval between nRCT and surgery (HR = 2.39, CI95%: 1.17–4.88, p = 0.016) remained as independent predictive parameters.

Conclusions

These clinical parameters can be considered in the prognostication of sphincter-preserving surgery in case of low rectal adenocarcinoma. More future research is required in this area.

Integrative Molecular Characterization of Resistance to Neoadjuvant Chemoradiation in Rectal Cancer

PURPOSE

Molecular properties associated with complete response or acquired resistance to concurrent chemotherapy and radiotherapy (CRT) are incompletely characterized.Experimental Design: We performed integrated whole-exome/transcriptome sequencing and immune infiltrate analysis on rectal adenocarcinoma tumors prior to neoadjuvant CRT (pre-CRT) and at time of resection (post-CRT) in 17 patients [8 complete/partial responders, 9 nonresponders (NR)].

RESULTS

CRT was not associated with increased tumor mutational burden or neoantigen load and did not alter the distribution of established somatic tumor mutations in rectal cancer. Concurrent KRAS/TP53 mutations (KP) associated with NR tumors and were enriched for an epithelial-mesenchymal transition transcriptional program. Furthermore, NR was associated with reduced CD4/CD8 T-cell infiltrates and a post-CRT M2 macrophage phenotype. Absence of any local tumor recurrences, KP/NR status predicted worse progression-free survival, suggesting that local immune escape during or after CRT with specific genomic features contributes to distant progression.

CONCLUSIONS

Overall, while CRT did not impact genomic profiles, CRT impacted the tumor immune microenvironment, particularly in resistant cases.

Down-Staging after Two Different Preoperative Chemoradiation Schedules in Rectal Cancer

Aims

To compare preoperative downstaging, toxicity and sphincter-saving procedures obtained with preoperative radiotherapy and two different concomitant chemotherapy schedules.

Methods

From February 1997 to August 2001, 68 consecutive patients were treated with external radiotherapy (5040 cGy in 28 fractions) and concomitant chemotherapy: group a) 36 patients (10T2, 19T3, 7T4, 25 adenocarcinoma and 11 mucinous histology) were treated with cis-diamminedichloroplatinum bolus + 5-fluorouracil continuous infusion; group b) 32 patients (14 T2, 18 T3, 27 adenocarcinoma and 5 mucinous histology) were treated with 5-fluorouracil bolus ± mitomycin C. The interval between the end of radiotherapy and surgery ranged from 4 to 9 weeks.

Results

Group a) Overall downstaging was 63.9%. Longitudinal shrinkage of the neoplasm allowed conservative surgery in 6 of 11 patients with a pre-chemoradiation tumor location ≤3 cm from the external anal ring. When patients with adenocarcinoma (25/36) were studied separately from patients with mucinous histology, 7/25 patients (28%) were found to have no microscopic evidence of residual tumor (pTO); 8/25 (32%) were found to have only rare isolated cancer cells (pTmic); only 7/25 patients (28%) were found to have no change. Overall, 72% patients had downstaging. In contrast, only 5/11 (45.5%) of mucinous tumors had partial downstaging and 6/11 (54.5%) no downstaging at all. Group b) Overall downstaging was 46.9%. When patients with adenocarcinoma (27/32) were studied separately, 7/27 (26%) were found to have pTO, 3/27 (11.1%) pTmic, and 13/27 (48.1%) no change. Only 1/5 (20%) of mucinous tumors had downstaging and 4/5 (80%) had no downstaging at all. Overall toxicity was comparable among groups a and b, except for lower hematologic and gastrointestinal G3-4 toxicity observed in group a.

Conclusions

The overall response allowed conservative surgery in 56 (82.3%) of the 68 patients. Continuous infusion of 5-fluorouracil and diamminedichloroplatinum as a radipsensitizer determined better results in group a than group b (63.9% downstaging vs 46.9% even with a higher incidence of mucinous histology). Mucinous histology, for a definitely lower response rate, could benefit from an even more aggressive approach.

Neoadjuvant Therapy of Rectal Cancer New Treatment Perspectives

During the past two decades, significant advances have been made in the management of patients with rectal cancer. A number of clinical studies have demonstrated the efficacy of preoperative chemoradiation therapy with 5-fluorouracil (5-FU)-based regimens in decreasing local recurrences and improving survival and the likelihood of sphincter preservation. Although 5-FU has been the standard drug used in combination with radiation therapy for many years, new effective drugs including capecitabine, raltitrexed, irinotecan and oxaliplatin have been recently investigated in combination with radiation therapy in the preoperative setting. In addition, novel targeted biological agents including epidermal growth factor receptor inhibitors and vascular endothelial growth factor inhibitors have been shown to enhance the antitumor effect of both radiation and chemotherapy and are currently being explored in initial clinical trials. In the present review we summarize the results of adjuvant therapy. In addition, we will discuss the recently reported phase I-II trials with new drug plus radiation combinations in the preoperative treatment of patients with rectal cancer.

Relations of Changes in Serum Carcinoembryonic Antigen Levels before and after Neoadjuvant Chemoradiotherapy and after Surgery to Histologic Response and Outcomes in Patients with Locally Advanced Rectal Cancer

OBJECTIVES

The histologic response to neoadjuvant chemoradiotherapy (nCRT) has been intimately related to outcomes in locally advanced rectal cancer. Serum carcinoembryonic antigen (CEA) levels change after nCRT and after surgery as compared with before nCRT.

METHODS

The subjects were 149 patients with locally advanced rectal cancer who received nCRT between 2005 and 2013. The patients were divided into 4 groups according to the serum CEA levels: group 1, 55 patients with negative serum CEA levels before nCRT; group 2, 41 patients with positive serum CEA levels before nCRT that became negative after nCRT; group 3, 37 patients with positive serum CEA levels after nCRT that became negative after surgery; and group 4, 16 patients with positive serum CEA levels after nCRT as well as after surgery.

RESULTS

Pathological complete response, T downstaging, and tumor shrinkage were significantly higher in group 1 than in other groups. Disease-free survival was significantly poorer in group 4. The lack of a decrease in the serum CEA level in group 4 was most likely attributed to the persistence of micrometastases outside the resection field.

CONCLUSIONS

Changes in serum CEA levels measured before nCRT, after nCRT, and after surgery can be used to reliably predict the histologic response to nCRT and outcomes.

Gene expression levels of gamma-glutamyl hydrolase in tumor tissues may be a useful biomarker for the proper use of S-1 and tegafur-uracil/leucovorin in preoperative chemoradiotherapy for patients with rectal cancer

Purpose

Preoperative chemoradiotherapy (CRT) using 5-fluorouracil (5-FU)-based chemotherapy is the standard of care for rectal cancer. The effect of additional chemotherapy during the period between the completion of radiotherapy and surgery remains unclear. Predictive factors for CRT may differ between combination chemotherapy with S-1 and with tegafur-uracil/leucovorin (UFT/LV).

Methods

The subjects were 54 patients with locally advanced rectal cancer who received preoperative CRT with S-1 or UFT/LV. The pathological tumor response was assessed according to the tumor regression grade (TRG). The expression levels of 18 CRT-related genes were determined using RT-PCR assay.

Results

A pathological response (TRG 1-2) was observed in 23 patients (42.6%). In a multivariate logistic regression analysis for pathological response, the overall expression levels of four genes, HIF1A, MTHFD1, GGH and TYMS, were significant, and the accuracy rate of the predictive model was 83.3%. The effects of the gene expression levels of GGH on the response differed significantly according to the treatment regimen. The total pathological response rate of both high-GGH patients in the S-1 group and low-GGH patients in the UFT/LV group was 58.3%.

Conclusion

Additional treatment with 5-FU-based chemotherapy during the interval between radiotherapy and surgery is not beneficial in patients who have received 5-FU-based CRT. The expression levels of four genes, HIF1A, MTHFD1, GGH and TYMS, in tumor tissues can predict the response to preoperative CRT including either S-1 or UFT/LV. In particular, the gene expression level of GGH in tumor tissues may be a useful biomarker for the appropriate use of S-1 and UFT/LV in CRT.

Prognostic Role of Neutrophil-to-Lymphocyte Ratio in Locally Advanced Rectal Cancer Treated with Neoadjuvant Chemoradiotherapy

Background

Increasing evidence suggests that cancer-associated inflammation is associated with poorer outcomes. The neutrophil-to-lymphocyte ratio (NLR), considered as a systemic inflammation marker, is thought to predict prognoses in colorectal cancer. In this study, we explored the association between the NLR and prognoses following neoadjuvant chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC).

Material/Methods

From February 2002 to December 2012, a group of 202 patients diagnosed with LARC and receiving neoadjuvant CRT followed by radical surgery was included in our retrospective study. The associations between the pre-CRT NLR and clinicopathological characteristics, as well as the predictive value of pre-CRT NLR against survival outcomes, were analyzed.

Results

The average NLR was 2.7±1.5 (median 2.4, range 0.6–12.8). There were 63 (31.2%) patients with NLR ≥3.0, and 139 (68.8%) patients with NLR <3.0. Correlation analyses showed that no clinicopathological characteristics except age were associated with NLR. We did not find an association between NLR and survival outcomes. In multivariate Cox model analyses, the R1/R2 resection, lymph node ratio ≥0.1, and perineural/lymphovascular invasion were independently associated with worse disease-free survival and overall survival.

Conclusions

In our cohort, the NLR did not correlate with survival outcomes in LARC patients undergoing neoadjuvant CRT. The prognostic value of NLR should be validated in large-scale prospective studies.

Regression grading in neoadjuvant treated pancreatic cancer: an interobserver study

AIM

Several regression grading systems have been proposed for neoadjuvant chemoradiation-treated pancreatic ductal adenocarcinoma (PDAC). This study aimed to examine the utility, reproducibility and level of concordance of three most frequently used grading systems.

METHODS

Four gastrointestinal pathologists used the College of American Pathologists (CAP), Evans, MD Anderson Cancer Centre (MDA) regression grading systems to grade 14 selected cases (7-20 slides from each case) of neoadjuvant chemoradiation-treated PDAC. A postscoring discussion with each pathologist was conducted. The results were entered into a standardised data collection form and statistical analyses were performed.

RESULTS

There was little concordance across the three systems. The Kendall coefficient of concordance agreement scores were: CAP: 2-poor, 2-fair; Evans: 1-fair, 1-moderate, 2-good; MDA: 1-poor, 2-moderate, 1-good. Interpretation in all three grades in the CAP grading system was a source of discrepancy. Furthermore, using fibrosis as a criterion to assess regression was contentious. In the Evans system, quantifying tumour destruction using arbitrary percentage cut-offs (ie, 9% vs 10%; 50% vs 51%, etc) was imprecise and subjective. Although the MDA system generated greatest concordance, this was due to 'oversimplification' surrounding wide, arbitrarily assigned thresholds of </> 5% of tumour.

CONCLUSIONS

All systems lacked precision and clarity for accurate regression grading. Presently the clinical utility and impact of histological regression grading in patient management is questionable. There is a need to re-evaluate regression grading in the pancreas and establish a reproducible, clinically relevant grading system.

An integrative approach for the identification of prognostic and predictive biomarkers in rectal cancer

Introduction

Colorectal cancer is the third most common cancer in the world, a small fraction of which is represented by locally advanced rectal cancer (LARC). If not medically contraindicated, preoperative chemoradiotherapy, represent the standard of care for LARC patients. Unfortunately, patients shows a wide range of response rates in which approximately 20% has a complete pathological response, whereas in 20 to 40% the response is poor or absent.

Results

The following specific gene signature, able to discriminate responders' patients from non-responders, were founded: AKR1C3, CXCL11, CXCL10, IDO1, CXCL9, MMP12 and HLA-DRA. These genes are mainly involved in immune system pathways and interact with drugs traditionally used in the adjuvant treatment of rectal cancer.

Discussion

The present study suggests that new ideas for therapy could be found not only limited to studying genes differentially expressed between the two groups of patients but deepening the mechanisms, associated to response, in which they are involved.

Methods

Gene expression studies performed by: Agostini et al., Rimkus et al. and Kim et al. have been merged through a meta-analysis of the raw data. Gene expression data-sets have been processed using A-MADMAN. Common differentially expressed gene (DEG) were identified through SAM analysis. To further characterize the identified DEG we deeply investigated its biological role using an integrative computational biology approach.

Predictive value of vrk 1 and 2 for rectal adenocarcinoma response to neoadjuvant chemoradiation therapy: a retrospective observational cohort study

Background

Neoadjuvant chemoradiotherapy (NACRT) followed by surgical resection is the standard therapy for locally advanced rectal cancer. However, tumor response following NACRT varies, ranging from pathologic complete response to disease progression. We evaluated the kinases VRK1 and VRK2, which are known to play multiple roles in cellular proliferation, cell cycle regulation, and carcinogenesis, and as such are potential predictors of tumor response and may aid in identifying patients who could benefit from NACRT.

Methods

Sixty-seven pretreatment biopsies were examined for VRK1 and VRK2 expression using tissue microarrays. VRK1 and VRK2 Histoscores were combined by linear addition, resulting in a new variable designated as “composite score”, and the statistical significance of this variable was assessed by univariate and multivariate logistic regression. The Hosmer-Lemeshow goodness-of-fit test and area under the ROC curve (AUC) analysis were carried out to evaluate calibration and discrimination, respectively. A nomogram was also developed.

Results

Univariate logistic regression showed that tumor size as well as composite score were statistically significant. Both variables remained significant in the multivariate analysis, obtaining an OR for tumor size of 0.65 (95 % CI, 0.45–0.94; p = 0.021) and composite score of 1.24 (95 % CI, 1.07–1.48; p = 0.005). Hosmer-Lemeshow test showed an adequate model calibration (p = 0.630) and good discrimination was also achieved, AUC 0.79 (95 % CI, 0.68–0.90).

Conclusions

This study provides novel data on the role of VRK1 and VRK2 in predicting tumor response to NACRT, and we propose a model with high predictive ability which could have a substantial impact on clinical management of locally advanced rectal cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2574-9) contains supplementary material, which is available to authorized users.

Association of thymidylate synthase polymorphisms with the tumor response to preoperative chemoradiotherapy in rectal cancer: a systematic review and meta-analysis

Preoperative chemoradiotherapy (pCRT) followed by surgery is currently the standard therapy for patients with locally advanced rectal cancer. It is very important to develop biomarkers to prior identify the patients who have a higher likelihood of responding to pCRT. Recently, a series of studies have been conducted to investigate the association of thymidylate synthase (TYMS) polymorphisms with the tumor response to pCRT in rectal cancer, but the results were not consistent and conclusive. In the present study, we performed a systematic literature search for relevant studies up to 30 March 2015 and conducted a meta-analysis to summarize and clarify the association between the TYMS polymorphisms and the tumor response to pCRT in rectal cancer. Finally, 7 studies containing 892 cases for TYMS 2R/3R polymorphism, 7 studies involving 715 cases for TYMS 1494del6 polymorphism and 6 studies containing 616 cases for TYMS 5' untranslated region (UTR) expression allele polymorphism were analyzed in the meta-analysis. The results suggested that TYMS 2R/3R was associated with the response and the patients with 2R/2R or 2R/3R genotype with rectal cancer might benefit more from pCRT than others. On the contrary, neither 1494del6 nor 5'UTR expression allele polymorphisms was associated with the response to pCRT.

Phase I study of pre-operative continuous 5-FU and sorafenib with external radiation therapy in locally advanced rectal adenocarcinoma

PURPOSE

The standard of care in locally advanced rectal cancer is preoperative treatment with fluoropyrimidine-based chemoradiotherapy. Sorafenib works synergistically with radiation and inhibits Ras/Raf, PDFGR, and VEGFR. This phase I study evaluated the safety and efficacy of sorafenib with infusional 5-fluorouracil (5-FU) and radiation in patients with locally advanced rectal cancer.

METHODS AND MATERIALS

Patients with confirmed stage II or III rectal cancer were recruited in 4 cohorts of 3 patients per dose level, with an expansion cohort at the maximum tolerated dose. A 3+3 dose escalation design was used. Radiation was given in 28 fractions at 1.8 Gy (50.4 Gy) day 1-5 at all dose levels. Initial dose of sorafenib was 200mg qd and titrated up to 400mg BID to determine the MTD. Standard dose of infusional 5-FU was used (225 mg/m(2)/24h). Patients underwent surgery 6-10 weeks after neoadjuvant therapy.

RESULTS

Between August 2011 and August 2014, 17 patients (median age of 54 years) were enrolled. After toxicities requiring dose interruptions were observed in cohort 1 (2 patients with grade 2 (G2) and grade 3 (G3) hand foot skin reaction and 1 patient with G2 mucositis), the protocol was amended, changing administration of chemotherapy and sorafenib from daily to days 1-5 only. With the amended protocol, the primary G3 toxicity was hypertension in 2 patients at the 200-mg adjusted dose level (day1-5) and 1 patient at the 400-mg twice daily dose level. One patient had G3 ALT elevation at 400mg, and no grade IV toxicities were observed. G1 and G2 toxicities included hand-foot skin reaction, diarrhea, mucositis, nausea, fatigue, and proctitis. No perioperative complications were seen. Two patients refused to undergo surgery. The pathological complete remission (pCR) rate was 33%, and downstaging was observed in 85.7% of patients. Median neoadjuvant rectal cancer score was 8.7.

CONCLUSIONS

With the changed dosing schedule, this regimen was very well tolerated. The tumor pCR and downstaging rates are encouraging and support further clinical investigation of this regimen.

MTHFR C677T Polymorphism is Associated with Tumor Response to Preoperative Chemoradiotherapy: A Result Based on Previous Reports

BACKGROUND

Preoperative chemoradiotherapy (pRCT) followed by surgery has been widely practiced in locally advanced rectal cancer, esophageal cancer, gastric cancer and other cancers. However, the therapy also exerts some severe adverse effects and some of the patients show poor or no response. It is very important to develop biomarkers (e.g., gene polymorphisms) to identify patients who have a higher likelihood of responding to pRCT. Recently, a series of reports have investigated the association of the genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and epidermal growth factor receptor (EGFR) genes with the tumor response to pRCT; however, the results were inconsistent and inconclusive.

MATERIAL AND METHODS

A systematic review and meta-analysis was performed by searching relevant studies about the association of MTHFR and EGFR polymorphisms with the tumor regression grade (TRG) in response to pRCT in databases of PubMed, EMBAS, Web of science, Chinese National Knowledge Infrastructure, and Wanfang database up to March 30, 2015. The pooled odds ratios (ORs) with corresponding 95% confidence intervals (95% CIs) were calculated to assess the strength of the association under 5 genetic models.

RESULTS

A total of 11 eligible articles were included in the present meta-analysis, of which 8 studies were performed in rectal cancer and 3 studies were performed in esophageal cancer. We finally included 8 included studies containing 839 cases for MTHFR C677T, 5 studies involving 634 cases for MTHFR A1298C, 3 studies containing 340 cases for EGFR G497A, and 4 studies containing 396 cases for EGFR CA repeat. The pooled analysis results indicated that MTHFR C677T might be correlated with the tumor response to pRCT under the recessive model (CC vs. CTTT) in overall analysis (OR=1.426(1.074-1.894), P=0.014), rectal cancer (OR=1.483(1.102-1.996), P=0.009), and TRG 1-2 vs. 3-5 group (OR=1.423(1.046-1.936), P=0.025), while other polymorphism including MTHFR A1298C, EGFR G497A, and EGFR CA repeat polymorphisms exerted significant association under all genetic models in overall analysis or subgroup analysis.

CONCLUSIONS

MTHFR C677T might be correlated with the tumor response to pRCT. Further well-designed, larger-scale epidemiological studies are needed to validate our results.

Clinical predictive circulating peptides in rectal cancer patients treated with neoadjuvant chemoradiotherapy

Preoperative chemoradiotherapy is worldwide accepted as a standard treatment for locally advanced rectal cancer. Current standard of treatment includes administration of ionizing radiation for 45-50.4 Gy in 25-28 fractions associated with 5-fluorouracil administration during radiation therapy. Unfortunately, 40% of patients have a poor or absent response and novel predictive biomarkers are demanding. For the first time, we apply a novel peptidomic methodology and analysis in rectal cancer patients treated with preoperative chemoradiotherapy. Circulating peptides (Molecular Weight <3 kDa) have been harvested from patients' plasma (n = 33) using nanoporous silica chip and analyzed by Matrix-Assisted Laser Desorption/Ionization-Time of Flight mass spectrometer. Peptides fingerprint has been compared between responders and non-responders. Random Forest classification selected three peptides at m/z 1082.552, 1098.537, and 1104.538 that were able to correctly discriminate between responders (n = 16) and non-responders (n = 17) before therapy (T0) providing an overall accuracy of 86% and an area under the receiver operating characteristic (ROC) curve of 0.92. In conclusion, the nanoporous silica chip coupled to mass spectrometry method was found to be a realistic method for plasma-based peptide analysis and we provide the first list of predictive circulating biomarker peptides in rectal cancer patients underwent preoperative chemoradiotherapy.

A functional biological network centered on XRCC3: a new possible marker of chemoradiotherapy resistance in rectal cancer patients

Preoperative chemoradiotherapy is widely used to improve local control of disease, sphincter preservation and to improve survival in patients with locally advanced rectal cancer. Patients enrolled in the present study underwent preoperative chemoradiotherapy, followed by surgical excision. Response to chemoradiotherapy was evaluated according to Mandard's Tumor Regression Grade (TRG). TRG 3, 4 and 5 were considered as partial or no response while TRG 1 and 2 as complete response. From pretherapeutic biopsies of 84 locally advanced rectal carcinomas available for the analysis, only 42 of them showed 70% cancer cellularity at least. By determining gene expression profiles, responders and non-responders showed significantly different expression levels for 19 genes (P < 0.001). We fitted a logistic model selected with a stepwise procedure optimizing the Akaike Information Criterion (AIC) and then validated by means of leave one out cross validation (LOOCV, accuracy = 95%). Four genes were retained in the achieved model: ZNF160, XRCC3, HFM1 and ASXL2. Real time PCR confirmed that XRCC3 is overexpressed in responders group and HFM1 and ASXL2 showed a positive trend. In vitro test on colon cancer resistant/susceptible to chemoradioterapy cells, finally prove that XRCC3 deregulation is extensively involved in the chemoresistance mechanisms. Protein-protein interactions (PPI) analysis involving the predictive classifier revealed a network of 45 interacting nodes (proteins) with TRAF6 gene playing a keystone role in the network. The present study confirmed the possibility that gene expression profiling combined with integrative computational biology is useful to predict complete responses to preoperative chemoradiotherapy in patients with advanced rectal cancer.

Predictive and prognostic biomarkers for neoadjuvant chemoradiotherapy in locally advanced rectal cancer

Locally advanced rectal cancer is regularly treated with trimodality therapy consisting of neoadjuvant chemoradiation, surgery and adjuvant chemotherapy. There is a need for biomarkers to assess treatment response, and aid in stratification of patient risk to adapt and personalise components of the therapy. Currently, pathological stage and tumour regression grade are used to assess response. Experimental markers include proteins involved in cell proliferation, apoptosis, angiogenesis, the epithelial to mesenchymal transition and microsatellite instability. As yet, no single marker is sufficiently robust to have clinical utility. Microarrays that screen a tumour for multiple promising candidate markers, gene expression and microRNA profiling will likely have higher yield and it is expected that a combination or panel of markers would prove most useful. Moving forward, utilising serial samples of circulating tumour cells or circulating nucleic acids can potentially allow us to demonstrate tumour heterogeneity, document mutational changes and subsequently measure treatment response.

Low expression of chloride channel accessory 1 predicts a poor prognosis in colorectal cancer

BACKGROUND

Chloride channel accessory 1 (CLCA1) is a CLCA protein that plays a functional role in regulating the differentiation and proliferation of colorectal cancer (CRC) cells. Here we investigated the relationship between the level of CLCA1 and the prognosis of CRC.

METHODS

First, the level of CLCA1 was detected quantitatively in normal and cancerous colonic epithelial tissues with immunohistochemistry. Next, the correlations between CLCA1 expression, pathological tumor features, and the overall survival rate of patients was analyzed. Finally, 3 publicly available data sets from the Gene Expression Omnibus were examined: normal CRC versus early CRC (GSE4107), primary CRC versus metastatic lesions (GSE28702), and low chromosomal instability versus high chromosomal instability (GSE30540).

RESULTS

The expression of CLCA1 was decreased markedly in tumor specimens. CLCA1 expression was correlated significantly with the histological grade (P < .01) and lymph node metastasis (P < .01). A significantly poorer overall survival rate was found in patients with low levels of CLCA1 expression versus those with high expression levels (P < .05). The results confirmed that the low expression of CLCA1 in CRC was highly associated with tumorigenesis, metastasis, and high chromosomal instability. In addition, the loss of CLCA1 disrupted the differentiation of human colon adenocarcinoma cells (Caco-2) in vitro.

CONCLUSIONS

These findings suggest that CLCA1 levels may be a potential predictor of prognosis in primary human CRC. Low expression of CLCA1 predicts disease recurrence and lower survival, and this has implications for the selection of patients most likely to need and benefit from adjuvant chemotherapy. Cancer 2015;121:1570–1580. © 2015 American Cancer Society.

Impression of prognosis regarding pathologic stage after preoperative chemoradiotherapy in rectal cancer

AIM: To ascertain pathologic stage as a prognostic indicator for rectal cancer patients receiving preoperative chemoradiotherapy (PCRT).

METHODS: Patients with mid- and low rectal carcinoma (magnetic resonance imaging - based clinical stage II or III) between 2000 and 2009 and treated with curative radical resection were identified. Patients were divided into two groups: PCRT and No-PCRT. Recurrence-free survival (RFS) was examined according to pathologic stage and addition of adjuvant treatment.

RESULTS: Overall, 894 patients were identified. Of these, 500 patients received PCRT. Adjuvant chemotherapy was delivered to 81.5% of the No-PCRT and 94.8% of the PCRT patients. Adjuvant radiotherapy was given to 29.4% of the patients in the No PCRT group. The 5-year RFS for the No-PCRT group was 92.6% for Stage I, 83.3% for Stage II, and 72.9% for Stage III. The 5-year RFS for the PCRT group was 95.2% for yp Stage 0, 91.7% for yp Stage I, 73.9% for yp Stage II, and 50.7% for yp Stage III.

CONCLUSION: Pathologic stage can predict prognosis in PCRT patients. 5-year RFS is significantly lower among PCRT patients than No-PCRT patients in pathologic stage II and III. These results should be taken into account when considering adjuvant treatment for patients treated with PCRT.

Adjuvant chemotherapy in rectal cancer: defining subgroups who may benefit after neoadjuvant chemoradiation and resection: a pooled analysis of 3,313 patients

Recent literature suggests that the benefit of adjuvant chemotherapy (aCT) for rectal cancer patients might depend on the response to neoadjuvant chemoradiation (CRT). Aim was to evaluate whether the effect of aCT in rectal cancer is modified by response to CRT and to identify which patients benefit from aCT after CRT, by means of a pooled analysis of individual patient data from 13 datasets. Patients were categorized into three groups: pCR (ypT0N0), ypT1-2 tumour and ypT3-4 tumour. Hazard ratios (HR) for the effect of aCT were derived from multivariable Cox regression analyses. Primary outcome measure was recurrence-free survival (RFS). One thousand seven hundred and twenty three (1723) (52%) of 3,313 included patients received aCT. Eight hundred and ninety eight (898) patients had a pCR, 966 had a ypT1-2 tumour and 1,302 had a ypT3-4 tumour. For 122 patients response, category was missing and 25 patients had ypT0N+. Median follow-up for all patients was 51 (0-219) months. HR for RFS with 95% CI for patients treated with aCT were 1.25(0.68-2.29), 0.58(0.37-0.89) and 0.83(0.66-1.10) for patients with pCR, ypT1-2 and ypT3-4 tumours, respectively. The effect of aCT in rectal cancer patients treated with CRT differs between subgroups. Patients with a pCR after CRT may not benefit from aCT, whereas patients with residual tumour had superior outcomes when aCT was administered. The test for interaction did not reach statistical significance, but the results support further investigation of a more individualized approach to administer aCT after CRT and surgery based on pathologic staging.

Neutrophil-lymphocyte ratio predicts pathologic tumor response and survival after preoperative chemoradiation for rectal cancer

Background

Neutrophil-lymphocyte ratio (NLR) reflects the balance between pro- and anti-tumor immune activities. We evaluated whether NLR is associated with pathologic tumor response and prognosis in rectal cancer patients that underwent preoperative chemoradiaton therapy (CRT) with surgery.

Methods

One hundred two patients with rectal cancer that were treated by preoperative CRT followed by surgery were enrolled. A total of 50.4 GY of radiation and 5-FU-based chemotherapy were delivered. An NLR ≥ 3 was considered to be elevated. Pathologic tumor response based on ypTNM stage was categorized into two groups, good response (n = 35, pathologic complete response and ypTNM I) and poor response groups (n = 67, ypTNM II, III, and IV).

Results

Twenty-five patients (24.5%) had elevated NLR. Multivariate analysis showed that an elevated CEA level (p = 0.001), larger tumor (p = 0.03), and elevated NLR (p = 0.04) were significant predictors for a poor response. Poor pathological tumor response and elevated NLR were risk factors for cancer-specific and recurrence-free survivals.

Conclusion

An elevated NLR before CRT can be used as predictors for poor tumor response and unfavorable prognostic factors. Dominant pro-tumor activities of neutrophils or reduced anti-tumor immune response by lymphocytes, as determined by NLR, may have a impact on poor tumor response and unfavorable prognosis.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2482-14-94) contains supplementary material, which is available to authorized users.

Association between ERCC1 and TS mRNA levels and disease free survival in colorectal cancer patients receiving oxaliplatin and fluorouracil (5-FU) adjuvant chemotherapy

Background

Aim was to explore the association of ERCC1 and TS mRNA levels with the disease free survival (DFS) in Chinese colorectal cancer (CRC) patients receiving oxaliplatin and 5-FU based adjuvant chemotherapy.

Methods

Total 112 Chinese stage II-III CRC patients were respectively treated by four different chemotherapy regimens after curative operation. The TS and ERCC1 mRNA levels in primary tumor were measured by real-time RT-PCR. Kaplan–Meier curves and log-rank tests were used for DFS analysis. The Cox proportional hazards model was used for prognostic analysis.

Results

In univariate analysis, the hazard ratio (HR) for the mRNA expression levels of TS and ERCC1 (logTS: HR = 0.820, 95% CI = 0.600 - 1.117, P = 0.210; logERCC1: HR = 1.054, 95% CI = 0.852 - 1.304, P = 0.638) indicated no significant association of DFS with the TS and ERCC1 mRNA levels. In multivariate analyses, tumor stage (IIIc: reference, P = 0.083; IIb: HR = 0.240, 95% CI = 0.080 - 0.724, P = 0.011; IIc: HR < 0.0001, P = 0.977; IIIa: HR = 0.179, 95% CI = 0.012 - 2.593, P = 0.207) was confirmed to be the independent prognostic factor for DFS. Moreover, the Kaplan-Meier DFS curves showed that TS and ERCC1 mRNA levels were not significantly associated with the DFS (TS: P = 0.264; ERCC1: P = 0.484).

Conclusion

The mRNA expression of ERCC1 and TS were not applicable to predict the DFS of Chinese stage II-III CRC patients receiving 5-FU and oxaliplatin based adjuvant chemotherapy.

Pelvic exenterations for specific extraluminal recurrences in the era of total mesorectal excision: is there still a chance for cure?: a single-center review of patients with extraluminal pelvic recurrence for rectal cancer from March 2004 to November 2010

BACKGROUND

The benefits in terms of curative resection and survival of pelvic exenterations for specific extraluminal pelvic recurrences from rectal cancer in the era of total mesorectal excision were assessed.

METHODS

We conducted a single-center review of patients with extraluminal pelvic recurrence from colorectal cancer between March 2004 and November 2010. Twenty-seven pelvic exenterations (13 posterior and 14 total) were performed. Independent predicative factors such as age, sex, local control on first surgery, pelvic sidewall excision, initial International Union Against Cancer (UICC) staging, sphincter-preserving resection at first surgery, tumor presentation on computed tomography and magnetic resonance imaging (pelvis sidewall involvement, number of fixation sites, ureteral involvement), local disease-free interval, previous symptoms, and postoperative treatment were analyzed.

RESULTS

No operative mortality was noted in this series. Overall morbidity rate was 74%; 22% of the patients developed severe complications. Complete surgical clearance (R0) was obtained in 63% of the patients. The rate of R0 resections was lower in total pelvic exenteration (57%) than in posterior pelvic exenteration (69%). Three years overall survival and disease-free survival were 76% and 59%, respectively. Curative resection (R0) was the only independent prognostic factor for overall survival (P = .0016) and disease-free survival (P < .0001).

CONCLUSION

Pelvic exenterations for extraluminal pelvic recurrences from rectal cancer afford a high R0 resection rate with acceptable morbidity.

Tumor Regression Grading After Preoperative Chemoradiotherapy for Locally Advanced Rectal Carcinoma Revisited: Updated Results of the CAO/ARO/AIO-94 Trial

Purpose

We previously described the prognostic impact of tumor regression grading (TRG) on the outcome of patients with rectal carcinoma treated with preoperative chemoradiotherapy (CRT) in the CAO/ARO/AIO-94 trial. Here we report long-term results after a median follow-up of 132 months.

Patients and Methods

TRG after preoperative CRT was determined in 386 surgical specimens by the amount of viable tumor cells versus fibrosis, ranging from TRG 4 (no viable tumor cells) to TRG 0 (no signs of regression). Clinicopathologic parameters and TRG were correlated to the cumulative incidence of local recurrence, distant metastasis, and disease-free survival (DFS).

Results

Ten-year cumulative incidence of distant metastasis and DFS were 10.5% and 89.5% for patients with TRG 4 (complete regression), 29.3% and 73.6% for TRG 2 and 3 (intermediate regression), and 39.6% and 63% for TRG 0 and 1 (poor regression), respectively (P = .005 and P = .008, respectively). On multivariable analysis, residual lymph node metastasis (ypN+) and TRG were the only independent prognostic factors for cumulative incidence of distant metastasis (P < .001 and P = .035, respectively) and DFS (P < .001 and P = .039, respectively), whereas local recurrence was significantly affected by ypN status (P < .001) and lymphatic invasion (P = .026).

Conclusion

Complete and intermediate tumor regressions were associated with improved long-term outcome in patients with rectal carcinoma after preoperative CRT independent of clinicopathologic parameters. This classification system needs to be prospectively tested in multiple data sets to validate its reproducibility in a wider setting.

Relationship between histologic response and the degree of tumor shrinkage after chemoradiotherapy in patients with locally advanced rectal cancer

BACKGROUND

Preoperative chemoradiotherapy (CRT) significantly decreases local recurrence in advanced rectal cancer. We studied whether the degree of tumor shrinkage can be used as a predictor of histologic response.

METHODS

The subjects were 114 patients with locally advanced rectal cancer who underwent total mesorectal excision after receiving radiotherapy combined with uracil/tegafur (UFT) or S-1. The degree of tumor shrinkage based on barium enema examination and magnetic resonance imaging (MRI) were assessed before CRT and immediately before surgery.

RESULTS

A histologic complete response (ypCR), histologic marked regression, T and N downstaging were associated with significantly higher tumor-shrinkage rates on barium enema (P < 0.01, P < 0.01, P < 0.01, and P < 0.01, respectively) as well as on MRI (P < 0.01, P < 0.01, P < 0.01, and P = 0.01, respectively). On multivariate analysis, ypCR and histologic marked regression were significantly related only to tumor-shrinkage rates on barium enema (P < 0.01 and P < 0.01, respectively), and were not related to tumor-shrinkage rates on MRI.

CONCLUSIONS

The degree of tumor shrinkage is closely related to the final histologic response. Two-dimensionally evaluated tumor-shrinkage rates based on barium enema are adequate for the prediction of histologic response.

How reliable is current imaging in restaging rectal cancer after neoadjuvant therapy?

In patients with advanced rectal cancer, neoadjuvant chemo radiotherapy provides tumor downstaging and downsizing and complete pathological response in up to 30% of cases. After proctectomy complete pathological response is associated with low rates of local recurrence and excellent long term survival. Several authors claim a less invasive surgery or a non operative policy in patients with partial or clinical complete response respectively, however to identify patients with true complete pathological response before surgical resection remains a challenge. Current imaging techniques have been reported to be highly accurate in the primary staging of rectal cancer, however neoadjuvant therapy course produces deep modifications on cancer tissue and on surrounding structures such as overgrowth fibrosis, deep stroma alteration, wall thickness, muscle disarrangement, tumor necrosis, calcification, and inflammatory infiltration. As a result, the same imaging techniques, when used for restaging, are far less accurate. Local tumor extent may be overestimated or underestimated. The diagnostic accuracy of clinical examination, rectal ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography using 18F-fluoro-2’-deoxy-D-glucose ranges between 25% and 75% being less than 60% in most studies, both for rectal wall invasion and for lymph nodes involvement. In particular the ability to predict complete pathological response, in order to tailor the surgical approach, remains low. Due to the radio-induced tissue modifications, combined with imaging technical aspects, low rate accuracy is achieved, making modern imaging techniques still unreliable in restaging rectal cancer after chemo-radiotherapy.

Neoadjuvant chemoradiation for distal rectal cancer: 5-year updated results of a randomized phase 2 study of neoadjuvant combined modality chemoradiation for distal rectal cancer

PURPOSE

To assess the efficacy of 2 different approaches to neoadjuvant chemoradiation for distal rectal cancers.

METHODS AND MATERIALS

One hundred six patients with T3/T4 distal rectal cancers were randomized in a phase 2 study. Patients received either continuous venous infusion (CVI) of 5-Fluorouracil (5-FU), 225 mg/m(2) per day, 7 days per week plus pelvic hyperfractionated radiation (HRT), 45.6 Gy at 1.2 Gy twice daily plus a boost of 9.6 to 14.4 Gy for T3 or T4 cancers (Arm 1), or CVI of 5-FU, 225 mg/m(2) per day, Monday to Friday, plus irinotecan, 50 mg/m(2) once weekly × 4, plus pelvic radiation therapy (RT), 45 Gy at 1.8 Gy per day and a boost of 5.4 Gy for T3 and 9 Gy for T4 cancers (Arm 2). Surgery was performed 4 to 10 weeks later.

RESULTS

All eligible patients (n=103) are included in this analysis; 2 ineligible patients were excluded, and 1 patient withdrew consent. Ninety-eight of 103 patients (95%) underwent resection. Four patients did not undergo surgery for either disease progression or patient refusal, and 1 patient died during induction chemotherapy. The median time of follow-up was 6.4 years in Arm 1 and 7.0 years in Arm 2. The pathological complete response (pCR) rates were 30% in Arm 1 and 26% in Arm 2. Locoregional recurrence rates were 16% in Arm 1 and 17% in Arm 2. Five-year survival rates were 61% and 75% and Disease-specific survival rates were 78% and 85% for Arm1 and Arm 2, respectively. Five second primaries occurred in patients on Arm 1, and 1 second primary occurred in Arm 2.

CONCLUSIONS

High rates of disease-specific survival were seen in each arm. Overall survival appears affected by the development of unrelated second cancers. The high pCR rates with 5-FU and higher dose radiation in T4 cancers provide opportunity for increased R0 resections and improved survival.

Meta-analysis of survival based on resection margin status following surgery for recurrent rectal cancer

AIM

To determine the presence and duration of survival advantages was investigated for resection margin status (R0, R1 or R2) following surgery for locally recurrent rectal cancer (LRRC).

METHOD

A systematic review of the literature was performed for studies comparing resection margin status for LRRC. Weighted mean differences and meta-analysis of hazard ratios were used as a measure of median and overall cumulative survival.

RESULTS

Twenty-two studies were included, providing outcome for 1460 patients undergoing surgery for LRRC. 57% underwent an R0 resection, 25% an R1 resection and 11% an R2 resection. The most commonly performed operations were abdominoperineal excision (35%), exenteration (23%) and anterior resection (21%). The range of median survival per resection margin was R0 28-92 months, R1 12-50 months, R2 6-17 months. Patients undergoing an R0 resection survived on average for 37.6 (95% confidence interval: 23.5-51.7) months longer than those undergoing R1 resection and 53.0 (31.2-74.8) months longer than those undergoing R2 resection. This correlated to a hazard ratio of 2.03 (1.73-2.38) for R0 vs R1 and 3.41 (2.21-5.25) for R0 vs R2. Patients undergoing R1 resection survived on average 13.3 (7.23-19.4) months longer than those undergoing R2 resection [hazard ratio of 1.68 (1.33-2.12)].

CONCLUSION

Patients undergoing R0 resection have the greatest survival advantage following surgery for recurrent rectal cancer. There is a survival advantage for R1 over R2 resection, but there may be no benefit of R2 resection over palliative treatment.

Biopsy specimens obtained 7 days after starting chemoradiotherapy (CRT) provide reliable predictors of response to CRT for rectal cancer

PURPOSE

Preoperative chemoradiation therapy (CRT) significantly decreases local recurrence in locally advanced rectal cancer. Various biomarkers in biopsy specimens obtained before CRT have been proposed as predictors of response. However, reliable biomarkers remain to be established.

METHODS AND MATERIALS

The study group comprised 101 consecutive patients with locally advanced rectal cancer who received preoperative CRT with oral uracil/tegafur (UFT) or S-1. We evaluated histologic findings on hematoxylin and eosin (H&E) staining and immunohistochemical expressions of Ki67, p53, p21, and apoptosis in biopsy specimens obtained before CRT and 7 days after starting CRT. These findings were contrasted with the histologic response and the degree of tumor shrinkage.

RESULTS

In biopsy specimens obtained before CRT, histologic marked regression according to the Japanese Classification of Colorectal Carcinoma (JCCC) criteria and the degree of tumor shrinkage on barium enema examination (BE) were significantly greater in patients with p21-positive tumors than in those with p21-negative tumors (P=.04 and P<.01, respectively). In biopsy specimens obtained 7 days after starting CRT, pathologic complete response, histologic marked regression according to both the tumor regression criteria and JCCC criteria, and T downstaging were significantly greater in patients with apoptosis-positive and p21-positive tumors than in those with apoptosis-negative (P<.01, P=.02, P=.01, and P<.01, respectively) or p21-negative tumors (P=.03, P<.01, P<.01, and P=.02, respectively). The degree of tumor shrinkage on both BE as well as MRI was significantly greater in patients with apoptosis-positive and with p21-positive tumors than in those with apoptosis-negative or p21-negative tumors, respectively. Histologic changes in H&E-stained biopsy specimens 7 days after starting CRT significantly correlated with pathologic complete response and marked regression on both JCCC and tumor regression criteria, as well as with tumor shrinkage on BE and MRI (P<.01, P<.01, P<.01, P<.01, and P=.03, respectively).

CONCLUSIONS

Immunohistochemical expressions of p21 and apoptosis together with histologic changes on H&E-stained biopsy specimens obtained 7 days after starting CRT are strong predictors of the response to CRT.

XIAP as a radioresistance factor and prognostic marker for radiotherapy in human rectal adenocarcinoma

A differential responsiveness of patients to ionizing radiation is observed after preoperative radiotherapy for rectal adenocarcinoma that might be related, in part, to an apoptosis defect. To establish if proteins of the apoptotic cascades [pro-apoptotic: active caspase 3, 8, and 9 and DIABLO (direct inhibitor of apoptosis-binding protein with low pI); anti-apoptotic: XIAP (X-linked inhibitor of apoptosis)] are involved, we analyzed their profile in radioresistant (SW480) and radiosensitive (SW48) human colorectal cell lines. We demonstrated that, after irradiation, the SW48 cells increased the expression of the pro-apoptotic proteins, whereas the SW480 cells increased the expression of the anti-apoptotic protein XIAP. Moreover, XIAP knockdown in SW480 cells enhanced the basal and radiation-induced apoptotic index; the propensity of the SW480 cells to undergo apoptosis after radiation was higher compared with SW48 cells. In a translational study of 38 patients with rectal carcinoma, we analyzed the apoptotic profile for tumor and noncancerous tissue for each biopsy specimen using IHC. According to their response to preoperative radiotherapy, patients were classified into two groups: responsive and nonresponsive. Although no difference in expression of caspase 3, 8, or 9 was observed in the tumor/normal tissue ratio between responsive and nonresponsive patients, the ratio decreased for DIABLO and increased for XIAP. In conclusion, inhibition of XIAP rescues cellular radiosensitivity and both DIABLO and XIAP might be potential predictive markers of radiation responsiveness in rectal adenocarcinoma.

Toward the non-surgical management of locally advanced rectal cancer

Neoadjuvant short-course radiotherapy and long-course chemoradiation (CRT) reduce local recurrence rates when compared to surgery alone and remain widely accepted as standard of care for patients with locally advanced rectal cancer. However, surgery is not without complications and a non-surgical approach in carefully selected patients warrants evaluation. A pathological complete response to CRT is associated with a significant improvement in survival and it has been suggested that a longer time interval between the completion of CRT and surgery increases tumor downstaging. Intensification of neoadjuvant treatment regimens to increase tumor downstaging has been evaluated in a number of clinical trials and more recently the introduction of neoadjuvant chemotherapy prior to CRT has demonstrated high rates of radiological tumor regression. Careful selection of patients using high-resolution MRI may allow a non-surgical approach in a subgroup of patients achieving a complete response to neoadjuvant therapies after an adequate time period. Clearly this needs prospective evaluation within a clinical trial setting, incorporating modern imaging techniques, and tissue biomarkers to allow accurate prediction and assessment of response.

International study group on rectal cancer regression grading: interobserver variability with commonly used regression grading systems

The aim of this study was to ascertain the level of concordance among gastrointestinal pathologists for regression grading in rectal cancers treated with neoadjuvant chemoradiation. Seventeen gastrointestinal pathologists participated using the Mandard, Dworak, and modified rectal cancer regression grading systems to grade 10 representative slides that were selected from 10 cases of rectal cancer treated with long-course neoadjuvant chemoradiation. The slides were scanned with a whole-slide scanner generating dynamic digitized images. The results showed very little concordance across the 3 grading systems, with κ values of 0.28, 0.35, and 0.38 for the Mandard, Dworak, and modified rectal cancer regression grading systems, respectively. In only 1 of 10 study cases was there unanimous grading concordance using the modified rectal cancer regression grading system. It was felt that these systems lacked precision and clarity for reproducible, accurate regression grading. The study concluded that there was a need for a simple, reproducible regression grading system with clear criteria, a cumulative or composite score taking into account all sections of the tumor bed that is sampled rather than the worst section (highest grade), and there should be a uniform method of sampling of these specimens.

Usefulness of perfusion CT to assess response to neoadjuvant combined chemoradiotherapy in patients with locally advanced rectal cancer

RATIONALE AND OBJECTIVES

To prospectively evaluate perfusion computed tomography (CT) for assessment of changes in tumor vascularity after chemoradiation therapy (CRT) in locally advanced rectal cancer and to analyze the correlation between baseline perfusion parameters and tumor response.

MATERIALS AND METHODS

Twenty patients with rectal cancer underwent baseline perfusion CT before CRT, and in 11 an examination after CRT was also performed. For each tumor, blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface area product (PS) were quantified. The Mann-Whitney U test compared baseline perfusion parameters of responders and nonresponders and pre- and post-CRT measurements were compared by the Wilcoxon signed-rank test (P < .05 statistically significant for both tests).

RESULTS

Baseline BF was significantly lower (P = .013) and MTT was significantly higher (P = .006) in responders. Both were able to discriminate responders from nonresponders with a sensitivity of 80% and 100% and a specificity of 73.3% and 86.7%, respectively, for BF and MTT. Baseline BV and PS were not significantly different in responders and nonresponders. Perfusion parameters changed significantly in post-CRT scans compared to baseline: BF (P = .003), BV (P = .003), and PS (P = .008) decreased, whereas MTT increased (P = .006).

CONCLUSION

Baseline BF and MTT can discriminate patients with a favorable response from those that fail to respond to CRT, potentially selecting high-risk patients with resistant tumors that may benefit from an aggressive preoperative treatment approach.

A multi-centre pathologist survey on pathological processing and regression grading of colorectal cancer resection specimens treated by neoadjuvant chemoradiation

To ascertain the approach and degree of consensus of pathologists in the handling and regression grading of colorectal cancer resection specimens treated with neoadjuvant chemoradiation, a ten-part questionnaire was circulated to 18 gastrointestinal pathologists in eight countries. The questions were specific and addressed pertinent issues related to colorectal cancer with neoadjuvant chemoradiation. There is a lack of consensus on how to handle the specimen, number of sections taken, correlation with pre- and post-operative radiological imaging, and especially, regression grading schema employed. Consensus in the form of guidelines is required so that the pathological assessment of these specimens will provide clinically relevant information for patient management, irrespective of location.

Predictive factors of the response of rectal cancer to neoadjuvant radiochemotherapy

Locally advanced rectal cancer is currently treated with pre-operative radiochemotherapy (pRCT), but the response is not uniform. Identification of patients with higher likelihood of responding to pRCT is clinically relevant, as patients with resistant tumors could be spared exposure to radiation or DNA-damaging drugs that are associated with adverse side effects. To highlight predictive biomarkers of response to pRCT, a systematic search of PubMed was conducted with a combination of the following terms: "rectal", "predictive", "radiochemotherapy", "neoadjuvant", "response" and "biomarkers". Genetic polymorphisms in epithelial growth factor receptor (EGFR) and thymidylate synthase (TS) genes, the expression of several markers, such as EGFR, bcl-2/bax and cyclooxygenase (COX)-2, and circulating biomarkers, such as serum carcinoembryonic antigen (CEA) level, are promising as predictor markers, but need to be further evaluated. The majority of the studies did not support the predictive value of p53, while the values of Ki-67, TS and p21 is still controversial. Gene expression profiles of thousands of genes using microarrays, microRNA studies and the search for new circulating molecules, such as human telomerase reverse transcriptase mRNA and cell-free DNA, are providing interesting results that might lead to the identification of new useful biomarkers. Evaluation of biomarkers in larger, prospective trials are required to guide therapeutic strategies.

Preoperative radiochemotherapy in t3 operable low rectal cancers: a gold standard?

BACKGROUND

Preoperative chemoradiation followed by total mesorectal excision (TME) has become a standard treatment of preoperatively staged T3 low rectal cancers in many institutions; however, a direct comparison of generalized preoperative versus selective adjuvant chemoradiation has never been assessed in a clinical practice setting.

PATIENTS

Over a 4-year period, 80 patients with T3 primary low adenocarcinoma of the rectum, judged operable at preoperative staging, were offered preoperative chemoradiation. Forty-seven patients (Group I) accepted the neoadjuvant treatment and 33 (Group II) preferred immediate surgery and postoperative chemoradiation if indicated.

RESULTS

Major postoperative complications occurred in 21% of Group I versus in 11% of Group II (p = 0.3) patients. After a mean follow-up of 92 months, the local recurrence rate was 4 and 9% (p = 0.4), metastasis rate was 30 and 24% (p = 0.5), 5-year survival probability was 0.79 (95% CI = 0.49-0.92) and 0.82 (95% CI = 0.70-1.00) (log-rank test, p = 0.6) for Group I and Group II, respectively.

CONCLUSIONS

In T3 operable low rectal cancers, selective postoperative radiochemotherapy yielded similar long-term results regarding recurrence rate and survival as extended preoperative chemoradiation.

Addition of bevacizumab to XELOX induction therapy plus concomitant capecitabine-based chemoradiotherapy in magnetic resonance imaging-defined poor-prognosis locally advanced rectal cancer: the AVACROSS study

BACKGROUND

Concomitant chemoradiotherapy followed by total mesorectal excision is standard treatment for locally advanced rectal cancer. This approach, however, focuses on local disease control and delays systemic treatment. Induction chemotherapy has the advantage of earlier administration of systemic therapy and may improve distant control. The objective of the current study was to assess the efficacy and toxicity of adding bevacizumab to induction chemotherapy followed by preoperative bevacizumab-based chemoradiotherapy in patients with locally advanced rectal cancer.

PATIENTS AND METHODS

Eligible patients had high-risk rectal adenocarcinoma defined by magnetic resonance imaging criteria. Treatment consisted of four 21-day cycles of bevacizumab (7.5 mg/kg) and XELOX (capecitabine plus oxaliplatin), followed by concomitant radiotherapy (50.4 Gy) plus bevacizumab (5 mg/kg every 2 weeks) and capecitabine (825 mg/m2 twice daily on days 1-15). Surgery was scheduled for 6-8 weeks after chemoradiotherapy. The primary endpoint was pathologic complete response (pCR).

RESULTS

Between July 2007 and July 2008, 47 patients were recruited. Among 45 patients who underwent surgery, pCR was achieved in 16 patients (36%; 95% confidence interval: 22.29%-51.27%), and an additional 17 patients (38%) had Dworak tumor regression grade 3. R0 resection was performed in 44 patients (98%). Most grade 3/4 adverse events occurred during the induction phase and included diarrhea (11%), asthenia (4%), neutropenia (6%), and thrombocytopenia (4%). Eleven patients (24%) required surgical reintervention.

CONCLUSIONS

Addition of bevacizumab to induction chemotherapy and chemoradiotherapy is feasible, with impressive activity and manageable toxicity. However, caution is recommended regarding surgical complications.

Circulating cell-free DNA: a promising marker of pathologic tumor response in rectal cancer patients receiving preoperative chemoradiotherapy

PURPOSE

The circulating cell-free DNA (cfDNA) in plasma has been reported to be a marker of cancer detection. The aim of this study was to investigate whether the cfDNA has a role as response biomarker in patients receiving preoperative chemoradiotherapy (CRT) for rectal cancer.

METHODS

Sixty-seven patients (median age 61 years; male/female 42/25) who underwent CRT for rectal cancer were evaluated. After tumor regression grade (TRG) classification was made, the patients were classified as having disease that responded (TRG 1-2) and that did not respond (TRG 3-5) to therapy. Plasma samples were obtained from patients before and after CRT. The cfDNA levels were analyzed by quantitative real-time polymerase chain reaction of β-globin. On the basis of the Alu repeats, the cfDNA was considered as either total (fragments of 115 bp, Alu 115) or tumoral (fragments of 247 bp, Alu 247). The association between the pre- or post-CRT levels and between variations during CRT of the Alu 247, Alu 115 repeat, and Alu 247/115 ratio (cfDNA integrity index) and the pathologic tumor response was analyzed.

RESULTS

The baseline levels of cfDNA were not associated with tumor response. The post-CRT levels of the cfDNA integrity index were significantly lower in responsive compared to nonresponsive disease (P = 0.0009). Both the median value of the Alu 247 repeat and the cfDNA integrity index decreased after CRT in disease that responded to therapy (P < 0.005 and P < 0.005, respectively) compared to disease that did not respond to therapy (P = 0.83 and P = 0.726, respectively). The results of the multivariable logistic regression analysis showed that only the cfDNA integrity index was significantly and independently associated with tumor response to treatment.

CONCLUSIONS

The plasma levels of the longer fragments (Alu 247) of cfDNA and the cfDNA integrity index are promising markers to predict tumor response after preoperative CRT for rectal cancer.

Thymidylate synthase genotype-directed neoadjuvant chemoradiation for patients with rectal adenocarcinoma

PURPOSE

Downstaging (DS) of rectal cancers is achieved in approximately 45% of patients with neoadjuvant fluorouracil (FU) -based chemoradiotherapy (CRT). Polymorphisms in the thymidylate synthase gene (TYMS) had previously defined two risk groups associated with disparate tumor DS rates (60% v 22%). We conducted a prospective single-institution phase II study using TYMS genotyping to direct neoadjuvant CRT for patients with rectal cancer.

PATIENTS AND METHODS

Patients with T3/T4, N0-2, M0-1 rectal adenocarcinoma were evaluated for germline TYMS genotyping. Patients with TYMS *2/*2, *2/*3, or *2/*4 (good risk) were treated with standard chemoradiotherapy using infusional FU at 225 mg/m²/d. Patients with TYMS *3/*3 or *3/*4 (poor risk) were treated with FU/RT plus weekly intravenous irinotecan at 50 mg/m². The primary end point was pathologic DS. Secondary end points included complete tumor response (ypT0), toxicity, recurrence rates, and overall survival.

RESULTS

Overall, 135 patients were enrolled, of whom 27.4% (37 of 135) were considered poor risk. The prespecified statistical goals were achieved, with DS and ypT0 rates reaching 64.4% and 20% for good-risk and 64.5% and 42% for poor-risk patients, respectively.

CONCLUSION

To our knowledge, this is the first study to prospectively use TYMS genotyping to direct neoadjuvant CRT in patients with rectal cancer. High rates of DS and ypT0 were achieved among both risk groups when personalized treatment was based on TYMS genotype. These results are encouraging, and further evaluation of this genotype-based strategy using a randomized study design for locally advanced rectal cancer is warranted.

Preoperative chemoradiotherapy using concurrent capecitabine and irinotecan in magnetic resonance imaging-defined locally advanced rectal cancer: impact on long-term clinical outcomes

PURPOSE

To assess long-term clinical outcomes of preoperative chemoradiotherapy of magnetic resonance imaging (MRI)-defined locally advanced rectal adenocarcinoma using concurrent irinotecan and capecitabine.

PATIENTS AND METHODS

One hundred ten patients without distant metastases entered this phase II trial North West/North Wales Clinical Oncology Group (NWCOG) -2 after MRI demonstration of tumor threatening (≤ 2 mm) or involving mesorectal fascia. Pelvic radiotherapy was given to 45 Gy in 25 fractions over 5 weeks with concurrent oral capecitabine at 650 mg/m(2) twice per day continuously days 1 through 35 and intravenous irinotecan at 60 mg/m(2) once weekly weeks 1 to 4. One hundred seven patients subsequently underwent surgical resection.

RESULTS

Comparing prechemoradiotherapy MRI scans with histology of the resected specimen, 72 patients (67%) had their initial MRI T stage downstaged and 64 patients (80%) had their N stage downstaged. Twenty-four patients (22%) demonstrated a pathologic complete response (ypCR) and 98 patients (92%) demonstrated a negative circumferential resection margin (> 1 mm). Three-year local recurrence-free survival was 96.9%, metastasis-free survival (MFS) was 71.1%, disease-free survival was (DFS) 63.5%, and overall survival (OS) was 88.2%. By univariate analysis, lower histologic stage was significantly associated with superior MFS, DFS, and OS, whether expressed as ypT0-2 versus ypT3-4, ypN0 versus ypN1-2, or ypCR/microfoci (near-ypCR) versus other patients. By multivariate analysis both ypN stage (P = .048) and ypCR/microfoci/others (P = .013) remained significant predictors of DFS but only ypCR/microfoci/others for OS (P = .005) with no difference in outcome between ypCR compared to microfoci.

CONCLUSION

This regimen demonstrates high response rates and promising long-term survival. Downstaging to ypCR/microfoci may be a useful short-term surrogate for long-term survival but needs validation in large phase III trials powered for survival outcomes.