Multicentre phase II trial of capecitabine and oxaliplatin in combination with radiotherapy for unresectable colorectal cancer: The CORGI-L study

Neoadjuvant rectal (NAR) score: Value evaluating the efficacy of neoadjuvant therapy and prognostic significance after surgery?

INTRODUCTION

The Neoadjuvant rectal (NAR) score is a new surrogate endpoint to be used in clinical trials for early determination of treatment response to different preoperative therapies. The aim is to further validate the NAR-score, primarily developed using chemoradiotherapy (CRT) with a delay to surgery 6-8 weeks, and explore its value using other schedules.

MATERIALS AND METHODS

The study included all 9978 patients diagnosed with non-metastasized RC in 2007-2015 that had undergone surgery and was registered in the Swedish Colorectal Cancer Registry. The patients of interest had either short-course radiotherapy (scRT)/CRT + delayed surgery, long-course radiotherapy (RT) + delayed surgery, (C)RT + additional chemotherapy, primary surgery, or scRT + immediate surgery. The scRT/CRT + delayed surgery groups were further divided based on time to surgery.

RESULTS

Mean NAR-score differed significantly (p < 0.0001) between different treatments. (C)RT + additional chemotherapy had the lowest mean score of 16.3 and CRT + delayed surgery had 17.7. There was a significant difference (p < 0.05) in overall survival (OS) and time to recurrence (TTR) of patients with a Low NAR-score (<8) compared to those with a High score (>16) for both CRT- and scRT, with a stronger correlation for CRT-patients. C-index for the NAR-score model (0.623) was not superior to when only pathological T- and N-stage was used (0.646).

CONCLUSIONS

The NAR-score is prognostic, but it is not better than pT- and pN-stage. However, the NAR-score can still discriminate between two treatments that have different cell killing effect and may still be of value in clinical trials as an easier method than pT- and N-stage.

Immune-Modulating Effects of Conventional Therapies in Colorectal Cancer

Biological heterogeneity and low inherent immunogenicity are two features that greatly impact therapeutic management and outcome in colorectal cancer. Despite high local control rates, systemic tumor dissemination remains the main cause of treatment failure and stresses the need for new developments in combined-modality approaches. While the role of adaptive immune responses in a small subgroup of colorectal tumors with inherent immunogenicity is indisputable, the challenge remains in identifying the optimal synergy between conventional treatment modalities and immune therapy for the majority of the less immunogenic cases. In this context, cytotoxic agents such as radiation and certain chemotherapeutics can be utilized to enhance the immunogenicity of an otherwise immunologically silent disease and enable responsiveness to immune therapy. In this review, we explore the immunological characteristics of colorectal cancer, the effects that standard-of-care treatments have on the immune system, and the opportunities arising from combining immune checkpoint-blocking therapy with immune-modulating conventional treatments.

Systemic immune response induced by oxaliplatin-based neoadjuvant therapy favours survival without metastatic progression in high-risk rectal cancer

Background

Systemic failure remains a challenge in rectal cancer. We investigated the possible systemic anti-tumour immune activity invoked within oxaliplatin-based neoadjuvant therapy.

Methods

In two high-risk patient cohorts, we assessed the circulating levels of the fms-like tyrosine kinase 3 ligand (Flt3L), a factor reflecting both therapy-induced myelosuppression and activation of tumour antigen-presenting dendritic cells, at baseline and following induction chemotherapy and sequential chemoradiotherapy, both modalities containing oxaliplatin. The primary end point was progression-free survival (PFS).

Results

In both cohorts, the median Flt3L level was significantly higher at completion of each sequential modality than at baseline. The 5-year PFS (most events being metastatic progression) was 68% and 71% in the two cohorts consisting of 33% and 52% T4 cases. In the principal cohort, a high Flt3L level following the induction chemotherapy was associated with low risk for a PFS event (HR: 0.15; P < 0.01). These patients also had available dose scheduling and toxicity data, revealing that oxaliplatin dose reduction during chemoradiotherapy, undertaken to maintain compliance to the radiotherapy protocol, was associated with advantageous PFS (HR: 0.47; P = 0.046).

Conclusion

In high-risk rectal cancer, oxaliplatin-containing neoadjuvant therapy may promote an immune response that favours survival without metastatic progression.

Early increase in circulating carbonic anhydrase IX during neoadjuvant treatment predicts favourable outcome in locally advanced rectal cancer

Background

Locally advanced rectal cancer (LARC) comprises heterogeneous tumours with predominant hypoxic components. The hypoxia-inducible metabolic shift causes microenvironmental acidification generated by carbonic anhydrase IX (CAIX) and facilitates metastatic progression, the dominant cause of failure in LARC.

Methods

Using a commercially available immunoassay, circulating CAIX was assessed in prospectively archived serial serum samples collected during combined-modality neoadjuvant treatment of LARC patients and correlated to histologic tumour response and progression-free survival (PFS).

Results

Patients who from their individual baseline level displayed serum CAIX increase above a threshold of 224 pg/ml (with 96 % specificity and 39 % sensitivity) after completion of short-course neoadjuvant chemotherapy (NACT) prior to long-course chemoradiotherapy and definitive surgery had significantly better 5-year PFS (94 %) than patients with below-threshold post-NACT versus baseline alteration (PFS rate of 56 %; p < 0.01). This particular CAIX parameter, ΔNACT, was significantly correlated with histologic ypT0–2 and ypN0 outcome (p < 0.01) and remained an independent PFS predictor in multivariate analysis wherein it was entered as continuous variable (p = 0.04).

Conclusions

Our results indicate that low ΔNACT, i.e., a weak increase in serum CAIX level following initial neoadjuvant treatment (in this case two cycles of the Nordic FLOX regimen), might be used as risk-adapted stratification to postoperative therapy or other modes of intensification of the combined-modality protocol in LARC.

Trial registration

ClinicalTrials.gov NCT00278694

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1557-6) contains supplementary material, which is available to authorized users.

Short- and Long-Term Quality of Life and Bowel Function in Patients With MRI-Defined, High-Risk, Locally Advanced Rectal Cancer Treated With an Intensified Neoadjuvant Strategy in the Randomized Phase 2 EXPERT-C Trial

OBJECTIVE

Intensified preoperative treatments have been increasingly investigated in locally advanced rectal cancer (LARC), but limited data are available for the impact of these regimens on quality of life (QoL) and bowel function (BF). We assessed these outcome measures in EXPERT-C, a randomized phase 2 trial of neoadjuvant capecitabine combined with oxaliplatin (CAPOX), followed by chemoradiation therapy (CRT), total mesorectal excision, and adjuvant CAPOX with or without cetuximab in magnetic resonance imaging-defined, high-risk LARC.

METHODS AND MATERIALS

QoL was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-CR29 questionnaires. Bowel incontinence was assessed using the modified Fecal Incontinence Severity Index questionnaire.

RESULTS

Compared to baseline, QoL scores during preoperative treatment were better for symptoms associated with the primary tumor in the rectum (blood and mucus in stool, constipation, diarrhea, stool frequency, buttock pain) but worse for global health status, role functioning, and symptoms related to the specific safety profile of each treatment modality. During follow-up, improved emotional functioning and lessened anxiety and insomnia were observed, but deterioration of body image, increased urinary incontinence, less sexual interest (men), and increased impotence and dyspareunia were observed. Cetuximab was associated with a deterioration of global health status during neoadjuvant chemotherapy but did not have any long-term detrimental effect. An improvement in bowel continence was observed after preoperative treatment and 3 years after sphincter-sparing surgery.

CONCLUSIONS

Intensifying neoadjuvant treatment by administering induction systemic chemotherapy before chemoradiation therapy improves tumor-related symptoms and does not appear to have a significantly detrimental effect on QoL and BF, in both the short and the long term.

Optimal Time Intervals between Pre-Operative Radiotherapy or Chemoradiotherapy and Surgery in Rectal Cancer?

BACKGROUND

In rectal cancer therapy, radiotherapy or chemoradiotherapy (RT/CRT) is extensively used pre-operatively to (i) decrease local recurrence risks, (ii) allow radical surgery in non-resectable tumors, and (iii) increase the chances of sphincter-saving surgery or (iv) organ-preservation. There is a growing interest among clinicians and scientists to prolong the interval from the RT/CRT to surgery to achieve maximal tumor regression and to diminish complications during surgery.

METHODS

The pros and cons of delaying surgery depending upon the aim of the pre-operative RT/CRT are critically evaluated.

RESULTS

Depending upon the clinical situation, the need for a time interval prior to surgery to allow tumor regression varies. In the first and most common situation (i), no regression is needed and any delay beyond what is needed for the acute radiation reaction in surrounding tissues to wash out can potentially only be deleterious. After short-course RT (5Gyx5) with immediate surgery, the ideal time between the last radiation fraction is 2-5 days, since a slightly longer interval appears to increase surgical complications. A delay beyond 4 weeks appears safe; it results in tumor regression including pathologic complete responses, but is not yet fully evaluated concerning oncologic outcome. Surgical complications do not appear to be influenced by the CRT-surgery interval within reasonable limits (about 4-12 weeks), but this has not been sufficiently explored. Maximum tumor regression may not be seen in rectal adenocarcinomas until after several months; thus, a longer than usual delay may be of benefit in well responding tumors if limited or no surgery is planned, as in (iii) or (iv), otherwise not.

CONCLUSION

A longer time interval after CRT is undoubtedly of benefit in some clinical situations but may be counterproductive in most situations. After short-course RT, long-term results from the clinical trials are not yet available to routinely recommend an interval longer than 2-5 days, unless the tumor is non-resectable at diagnosis.

High-dose radiotherapy (60 Gy) with oral UFT/folinic acid and escalating doses of oxaliplatin in patients with non-resectable locally advanced rectal cancer (LARC): a phase I trial

BACKGROUND

Consensus is that patients with locally advanced rectal cancer (LARC) should receive long-term chemoradiotherapy (CRT) before surgery. With the intent to offer the patients intensified concomitant chemotherapy (CT) to improve outcome and to assess tolerability and toxicity of oxaliplatin (Ox) a phase I trial of high dose pelvic radiotherapy (RT), fixed dose of oral UFT/l-leucovorin and increasing doses of weekly Ox were performed.

METHODS

Pelvic RT with 48.6 Gy/27 fractions was given to the primary tumour and the regional lymph nodes and a concurrent boost of 5.4 Gy/27 fractions with a final boost of 6 Gy/3 fractions was given to the gross tumour volume (GTV) (60 Gy/30 fractions). Concurrent with RT patients received a daily dose of UFT 300 mg/m(2) plus fixed dose l-leucovorin 22.5 mg 5/7 days and increasing weekly doses of Ox with 10 mg/m(2)/week from a start dose of 30 mg/m(2)/week to a maximum of 60 mg/m(2)/week. In addition, before and after CRT the patients received one course of TEGAFOX (UFT 300 mg/m(2) with l/leucovorin 22.5 mg Days 1-14 and Ox 130 mg/m(2) given on Day 1). Surgery was planned at least six weeks after the completion of the CRT.

RESULTS

From May 2005 to March 2009, 18 patients with LARC (16 primary, two recurrent) were included in this phase I trial. Toxicity was low with only 5-17% grade 3-4 toxicity. Fifteen patients (83%) were operated (14 R0 resection and 1 R1 resection) after completion of CRT. Five (33%) patients had a pathological complete response (ypCR). When ypCR was combined with yp few residual cells, the rate was 60%. Thirteen patients are still alive December 2011.

CONCLUSION

Preoperative high-dose RT and concomitant UFT with increasing doses of Ox up to 60 mg/m(2)/week was feasible with low toxicity, high ypCR rates and promising OS in patients with non-resectable LARC.

Neoadjuvant chemotherapy in MRI-staged high-risk rectal cancer in addition to or as an alternative to preoperative chemoradiation?

BACKGROUND

For patients with resectable rectal cancer chemoradiation (CRT) or short-course preoperative radiotherapy (SCPRT) reduces locoregional failure, without extending disease-free survival (DFS) or overall survival (OS). Compliance to postoperative adjuvant chemotherapy is poor. Neoadjuvant chemotherapy (NACT) offers an alternative strategy.

METHODS

A systematic computerised database search identified studies exploring NACT alone or NACT preceding/succeeding radiation. The primary outcome measure was pathological complete response (pCR). Secondary outcome measures included acute toxicity, surgical morbidity, circumferential resection margin, locoregional failure, DFS and OS.

RESULTS

Four case reports, 12 phase I/II studies, 4 randomised phase II and one randomised phase III study evaluated chemotherapy before CRT. Four prospective studies reviewed chemotherapy after CRT. Three phase II studies investigated chemotherapy using FOLFOX plus bevacizumab without radiotherapy. In 24 studies of 1271 patients, pCR varied from 7% to 36%, but with no impact on metastatic disease.

CONCLUSIONS

NACT before CRT delivers does not compromise CRT but has not increased pCR rates, R0 resection rate, improved DFS or reduced metastases. NACT following CRT is an interesting strategy, and the utility of NACT alone could be explored compared with SCPRT or CRT in selected patients with rectal cancer where the impact of radiotherapy on DFS and OS is marginal.

Oxaliplatin as a radiosensitiser for upper and lower gastrointestinal tract malignancies: what have we learned from a decade of translational research?

Some of the greatest advances in the treatment of solid malignancies have resulted from the combination of chemotherapy and radiotherapy treatments. This article comprehensively reviews the current clinical evidence for oxaliplatin-based chemo-radiotherapy that may improve local control and survival. In order to understand how clinical studies should be designed, the pre-clinical evidence for the use of oxaliplatin chemotherapy as a radiosensitising agent is appraised. Particular focus is placed on oxaliplatin's biological mechanisms of action, including cell cycle effects, the formation of DNA adducts and interstrand cross-links and the role of DNA repair proteins. At a clinical level, there is currently no evidence to suggest that oxaliplatin provides an additional benefit to concurrent chemo-radiation regimes that utilise fluoropyrimidines; we evaluate the reasons for this observation, the limitations of clinical trial design and the opportunities that currently exist to design clinical trials which are underpinned by an understanding of the basic biology.

The effects of short-course preoperative irradiation on local recurrence rate and survival in rectal cancer: a population-based nationwide study

BACKGROUND

Preoperative irradiation with 5 × 5 Gy in randomized trials reduces local recurrence rate and may improve survival in patients with resectable rectal cancer.

OBJECTIVE

The aim of this study was to determine whether the same favorable effects could be observed in a population-based study.

DESIGN

This study was conducted via a retrospective analysis of prospectively collected data from the Swedish Rectal Cancer Registry.

SETTINGS

This study examined population-based data from Sweden.

PATIENTS

All newly diagnosed rectal cancers in Sweden are reported to the Swedish Rectal Cancer Registry.

INTERVENTIONS

Between 1995 and 2001, 6878 patients (stages I-III) were operated on with an anterior resection, an abdominoperineal resection, or a Hartmann's procedure. Short-course irradiation was given to 41% of patients preoperatively. To reduce bias, patients operated on with a Hartmann procedure or older than 75 years were excluded when 5-year survival was analyzed (n = 3466). Tumors were analyzed according to height (0-5 cm, 6-10 cm, 11-15 cm).

MAIN OUTCOME MEASURES

Five-year cumulative local recurrence and survival rates.

RESULTS

The 5-year cumulative local recurrence rate was 6.3% (95% CI 5.4-7.4) for patients receiving preoperative irradiation and 12.1% (95% CI 10.8-13.5) for patients not receiving preoperative irradiation. Multivariate analyses indicated the risk of local recurrence was 50% lower for patients receiving preoperative irradiation compared with patients not receiving irradiation (hazard ratio = 0.50; 95% CI 0.40-0.62). Among patients younger than 76 years and operated on with an anterior resection or abdominoperineal resection, the 5-year cumulative survival rate was 0.70 (95% CI 0.69-0.72). Disease-free and overall survivals were higher in irradiated patients, and the difference was statistically significant in low tumors.

CONCLUSIONS

In this population-based analysis, the favorable effect of preoperative short-course irradiation on local recurrence rates, seen in randomized trials, was confirmed for the entire Swedish population irrespective of tumor height and stage. Data also suggested an effect on 5-year survival, especially in patients with low tumors (0-5 cm).

Rectal cancer radiotherapy: towards European consensus

BACKGROUND AND PURPOSE

During the first decade of the 21st century several important European randomized studies in rectal cancer have been published. In order to help shape clinical practice based on best scientific evidence, the International Conference on 'Multidisciplinary Rectal Cancer Treatment: Looking for an European Consensus' (EURECA-CC2) was organized. This article summarizes the consensus about imaging and radiotherapy of rectal cancer and gives an update until May 2010.

METHODS

Consensus was achieved using the Delphi method. Eight chapters were identified: epidemiology, diagnostics, pathology, surgery, radiotherapy and chemotherapy, treatment toxicity and quality of life, follow-up, and research questions. Each chapter was subdivided by topic, and a series of statements were developed. Each committee member commented and voted, sentence by sentence three times. Sentences which did not reach agreement after voting round # 2 were openly debated during the Conference in Perugia (Italy) December 2008. The Executive Committee scored percentage consensus based on three categories: "large consensus", "moderate consensus", "minimum consensus".

RESULTS

The total number of the voted sentences was 207. Of the 207, 86% achieved large consensus, 13% achieved moderate consensus, and only three (1%) resulted in minimum consensus. No statement was disagreed by more than 50% of members. All chapters were voted on by at least 75% of the members, and the majority was voted on by >85%. Considerable progress has been made in staging and treatment, including radiation treatment of rectal cancer.

CONCLUSIONS

This Consensus Conference represents an expertise opinion process that may help shape future programs, investigational protocols, and guidelines for staging and treatment of rectal cancer throughout Europe. In spite of substantial progress, many research challenges remain.

Radiosensitization of cancer cells by hydroxychalcones

Radiation sensitization is significantly increased by proteotoxic stress, such as a heat shock. We undertook an investigation, seeking to identify natural products that induced proteotoxic stress and then determined if a compound exhibited radiosensitizing properties. The hydroxychalcones, 2',5'-dihydroxychalcone (D-601) and 2,2'-dihydroxychalcone (D-501), were found to activate heat shock factor 1 (Hsf1) and exhibited radiation sensitization properties in colon and pancreatic cancer cells. The radiosensitization ability of D-601 was blocked by pretreatment with α-napthoflavone (ANF), a specific inhibitor of cytochrome P450 1A2 (CYP1A2), suggesting that the metabolite of D-601 is essential for radiosensitization. The study demonstrated the ability of hydroxychalcones to radiosensitize cancer cells and provides new leads for developing novel radiation sensitizers.

The effect on the small bowel of 5-FU and oxaliplatin in combination with radiation using a microcolony survival assay

Background

In locally advanced rectal cancer, 5-Fluorouracil (5-FU)-based chemoradiation is the standard treatment. The main acute toxicity of this treatment is enteritis. Due to its potential radiosensitizing properties, oxaliplatin has recently been incorporated in many clinical chemoradiation protocols. The aim of this study was to investigate to what extent 5-FU and oxaliplatin influence the radiation (RT) induced small bowel mucosal damage when given in conjunction with single or split dose RT.

Methods

Immune competent balb-c mice were treated with varying doses of 5-FU, oxaliplatin (given intraperitoneally) and total body RT, alone or in different combinations in a series of experiments. The small bowel damage was studied by a microcolony survival assay. The treatment effect was evaluated using the inverse of the slope (D₀) of the exponential part of the dose-response curve.

Results

In two separate experiments the dose-response relations were determined for single doses of RT alone, yielding D₀ values of 2.79 Gy (95% CI: 2.65 - 2.95) and 2.98 Gy (2.66 - 3.39), for doses in the intervals of 5-17 Gy and 5-10 Gy, respectively. Equitoxic low doses (IC5) of the two drugs in combination with RT caused a decrease in jejunal crypt count with significantly lower D₀: 2.30 Gy (2.10 - 2.56) for RT+5-FU and 2.27 Gy (2.08 - 2.49) for RT+oxaliplatin. Adding both drugs to RT did not further decrease D₀: 2.28 Gy (1.97 - 2.71) for RT+5-FU+oxaliplatin. A clearly higher crypt survival was noted for split course radiation (3 × 2.5 Gy) compared to a single fraction of 7.5 Gy. The same difference was seen when 5-FU and/or oxaliplatin were added.

Conclusion

Combining 5-FU or oxaliplatin with RT lead to an increase in mucosal damage as compared to RT alone in our experimental setting. No additional reduction of jejunal crypt counts was noted when both drugs were combined with single dose RT. The higher crypt survival with split dose radiation indicates a substantial recovery between radiation fractions. This mucosal-sparing effect achieved by fractionation was maintained also when chemotherapy was added.

Multidisciplinary treatment of resectable rectal cancer

This review identifies evidence that influences current practices in the multidisciplinary treatment and shapes future directions in the treatment of resectable rectal cancer. Recent advances in surgery, radiotherapy and systemic chemotherapy have provided measurable improvements in disease control, functional outcomes and quality of life for patients with rectal cancer. However, controversies remain regarding the optimum delivery of adjuvant therapies. Preoperative radiation either with or without concurrent chemotherapy demonstrates lower recurrence, with minimal survival benefit. Currently, the use of neoadjuvant standard fractionation chemoradiation versus short-course radiation without chemotherapy is controversial and under investigation. New combinations of chemotherapeutic agents and targeted therapies are also being evaluated. In addition, criteria for patient selection are being re-evaluated to determine the relative benefit of modern treatments, so that we may better tailor adjuvant therapy recommendations to be patient-specific. Recommendations for adjuvant treatments of rectal cancer are continuing to evolve; however, survival has been only marginally affected despite low incidence of local recurrence. Future trials should aim to address the role of adjuvant therapies utilizing new criteria, such as function, quality of life and impact on development of metastatic disease.