High-risk Locally Advanced Rectal Cancer Research Articles

Neoadjuvant S-1 and oxaliplatin plus bevacizumab therapy for high-risk locally advanced rectal cancer: A prospective multicenter phase II study.

We report the short/mid-term results of surgery for high-risk locally advanced rectal cancer (LARC) after neoadjuvant chemotherapy (NAC, four courses of S-1 + oxaliplatin+ bevacizumab) without radiotherapy with the primary aim of ypT0-2. High-risk LARC was defined as cT4b, mesorectal fascia (MRF) ≤1 mm (MRF+), or lateral lymph node metastasis (cLLN+) on high-resolution MRI. The planned 32 cases from April 2018 to December 2021 were all included. There were 10 patients at cT4b (31.2%), 26 MRF+ (81.3%), and 22 cLLN+ (68.8%). Thirteen (40.6%) underwent NAC after a colostomy for stenosis. NAC was completed in 26 (81.2%) cases. Grade 3 or higher adverse events occurred in six (18.7%). One patient developed progressive disease (3.2%). Eleven were ycT0-3MRF-LLN- (34.3%). Curative-intent surgery was performed on 31, with sphincter-preserving surgery in 20, abdominoperineal resection in nine, total pelvic exenteration in two, and lateral lymph node dissection in 24. Two had R1/2 resection (6.4%). A Grade 3 or higher postoperative complication rate occurred in 3.2%. Pathological complete response and ypT0-2 rates were 12.9% and 45.1%. Three-year disease-free survival rates (3yDFS) for ypT0-2 and ypT ≥3 were 81.2%, 46.6% (p = 0.061), and 3-year local recurrence rates (3yLR) were 0%, 48.8% (p = 0.015). 3yDFS for ycT0-3MRF-LLN- and ycT4/MRF+/LLN+ were 87.5%, 48.0% (p = 0.031) and 3yLR were 0%, 42.8% (p = 0.045). NAC yielded a clinically significant effect in about half of high-risk LARC patients. If NAC alone is ineffective, radiotherapy should be added, even if extended surgery is intended.

Neoadjuvant short-course radiotherapy followed by chemotherapy plus camrelizumab versus long-course chemoradiotherapy followed by chemotherapy for patients with locally advanced rectal cancer: A randomized, multicenter, open-label phase 3 trial (Union).

TPS3638 Background: Short-course preoperative radiotherapy (SCPRT) and long-course chemoradiotherapy (LCCRT) are standard neoadjuvant treatments for locally advanced rectal cancer (LARC). Further, the RAPIDO trial found that SCPRT combined with consolidation chemotherapy produced better short- and long-term outcomes than SCPRT alone for patients with high-risk LARC. A phase 2, single-arm trial of neoadjuvant SCPRT followed by camrelizumab (an anti-PD-1 antibody) plus chemotherapy demonstrated promising short-term outcomes in patients with LARC. The Union trial is evaluating the efficacy and safety of neoadjuvant SCPRT followed by camrelizumab plus chemotherapy versus LCCRT followed by chemotherapy in patients with LARC. Methods: The Union trial is enrolling patients aged 18-75 with histologically confirmed clinical stage T3-4/N+ adenocarcinoma of the rectum, Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and a tumor inferior margin less than 10 cm above the anal verge. Eligible patients are randomized in a 1:1 ratio to either arm A or arm B. Patients in arm A receive neoadjuvant treatment with SCPRT (a total of 25 Gy in 5 days) followed by camrelizumab (200 mg/m2 intravenous drip on day 1, every 3 weeks for 2 cycles) plus CAPOX (oxaliplatin 130 mg/m2 intravenous infusion over 2 hours on day 1, capecitabine 1000 mg/m2 oral twice daily, days 1–14, every 3 weeks for 2 cycles), surgery, and adjuvant treatment with camrelizumab plus CAPOX (6 cycles) followed by camrelizumab until the medication duration of camrelizumab reaches one year. Patients in arm B receive neoadjuvant treatment with LCCRT (capecitabine 825 mg/m2 twice daily, 5 days a week, combined with a total dose of 50.4 Gy in 28 days) followed by CAPOX (2 cycles), surgery, and adjuvant treatment with CAPOX (6 cycles). Randomization is stratified by clinical T stage (≤T3 vs T4) and clinical N stage (N0 vs N+). The primary endpoint is pathologic complete response (pCR). The secondary endpoints are 3-year event-free survival rate, overall survival, R0 resection rate, completion rate of neoadjuvant treatment, 3-year disease-free survival rate, tumor regression grading, safety, and quality of life. pCR is evaluated per the AJCC 8th Edition TRG scoring system as assessed by the blinded independent central review. Adverse events are graded by the National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0. Quality of life is assessed by the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire Core 30. This study began enrollment in July 2021 with a planned enrollment of 230 patients. Clinical trial information: NCT04928807 .

The value of post-operative chemotherapy after chemoradiotherapy in patients with high-risk locally advanced rectal cancer—results from the RAPIDO trial

Pre-operative chemoradiotherapy (CRT) rather than radiotherapy (RT) has resulted in fewer locoregional recurrences (LRRs), but no decrease in distant metastasis (DM) rate for patients with locally advanced rectal cancer (LARC). In many countries, patients receive post-operative chemotherapy (pCT) to improve oncological outcomes. We investigated the value of pCT after pre-operative CRT in the RAPIDO trial. Patients were randomised between experimental (short-course RT, chemotherapy and surgery) and standard-of-care treatment (CRT, surgery and pCT depending on hospital policy). In this substudy, we compared curatively resected patients from the standard-of-care group who received pCT (pCT+ group) with those who did not (pCT- group). Subsequently, patients from the pCT+ group who received at least 75% of the prescribed chemotherapy cycles (pCT ≥75% group) were compared with patients who did not receive pCT (pCT-/- group). By propensity score stratification (PSS), we adjusted for the following unbalanced confounders: age, clinical extramural vascular invasion, distance to the anal verge, ypT stage, ypN stage, residual tumour, serious adverse event (SAE) and/or readmission within 6 weeks after surgery and SAE related to pre-operative CRT. Cumulative probability of disease-free survival (DFS), DM, LRR and overall survival (OS) was analysed by Cox regression. In total, 396/452 patients had a curative resection. The number of patients in the pCT+, pCT >75%, pCT- and pCT-/- groups was 184, 112, 154 and 149, respectively. The PSS-adjusted analyses for all endpoints demonstrated hazard ratios between approximately 0.7 and 0.8 (pCT+ versus pCT-), and 0.5 and 0.8 (pCT ≥75% versus pCT-/-). However, all 95% confidence intervals included1. These data suggest a benefit of pCT after pre-operative CRT for patients with high-risk LARC, with approximately 20%-25% improvement in DFS and OS and 20%-25% risk reductions in DM and LRR. Compliance with pCT additionally reduces or improves all endpoints by 10%-20%. However, differences are not statistically significant.

Consolidation chemotherapy with capecitabine after neoadjuvant chemoradiotherapy in high-risk patients with locally advanced rectal cancer: Propensity score study.

BACKGROUNDThe effects of consolidation chemotherapy (CC) in neoadjuvant therapy in locally advanced rectal cancer (LARC) have been explored. However, the optimal neoadjuvant chemoradiotherapy (NCRT) and surgery interval, regimen, and cycles of chemotherapy remains unclear.AIMTo evaluate the effects of one to two cycles of CC with capecitabine on high-risk patients with LARC without extending NCRT and surgery interval.METHODSWe retrospectively evaluated high-risk patients with LARC, who were defined as having at least one of the following factors by magnetic resonance imaging: depth of invasion beyond the muscularis propria of more than 5 mm (cT3c-cT3d), T4, meso-rectal fascia or extramural vascular invasion positive, and treatment date between January 2015 and July 2019 in our center. Patients were divided into the CC and non-CC group according to whether they received CC (capecitabine 1000 mg/m2 twice daily from days 1 to 14 every 21 d) after NCRT. Propensity score matching (PSM) and inverse probability of treatment weight (IPTW) were used to balance the differences between the two groups. The main outcome was the complete response (CR) rate.RESULTSA total of 265 patients were enrolled: 136 patients in the CC group and 129 patients in the non-CC group. The median interval was 70 d (range, 37-168). The CR rate was 24.3% and 16.3% (P = 0.107) in the CC and non-CC groups’ original samples, respectively. After PSM and IPTW, the CR rate in the CC group was higher than that in non-CC group (27.6% vs 16.2%, P = 0.045; 25.9% vs 16.3%, P = 0.045). The median follow-up was 39.8 mo (range, 2.9-74.8), and there were no differences in 3-year non-regrowth disease-free survival nor overall survival in the original samples (73.2% vs 71.9%, P = 0.913; 92.3% vs 86.7%, P = 0.294), PSM (73.2% vs 73.5%, P = 0.865; 92.5% vs 89.3%, P = 0.612), and IPTW (73.8% vs 72.1%, P = 0.913; 92.4% vs 87.4%, P = 0.294). There was also no difference in grade 2 or higher acute toxicity during neoadjuvant therapy in the two groups (49.3% vs 53.5%, P = 0.492).CONCLUSIONOne to two cycles of CC with capecitabine after NCRT was safe and increased the CR rate in high-risk LARC but failed to improve the long-term outcomes.

Neoadjuvant FOLFOXIRI prior to chemoradiotherapy for high-risk (“ugly”) locally advanced rectal cancer: study protocol of a single-arm, multicentre, open-label, phase II trial (MEND-IT)

BackgroundThe presence of mesorectal fascia (MRF) invasion, grade 4 extramural venous invasion (EMVI), tumour deposits (TD) or extensive or bilateral extramesorectal (lateral) lymph nodes (LLN) on MRI has been suggested to identify patients with indisputable, extensive locally advanced rectal cancer (LARC), at high risk of treatment failure. The aim of this study is to evaluate whether or not intensified chemotherapy prior to neoadjuvant chemoradiotherapy improves the complete response (CR) rate in these patients.MethodsThis multicentre, single-arm, open-label, phase II trial will include 128 patients with non-metastatic high-risk LARC (hr-LARC), fit for triplet chemotherapy. To ensure a study population with indisputable, unfavourable prognostic characteristics, hr-LARC is defined as LARC with on baseline MRI at least one of the following characteristics; MRF invasion, EMVI grade 4, enlarged bilateral or extensive LLN at high risk of an incomplete resection, or TD. Exclusion criteria are the presence of a homozygous DPD deficiency, distant metastases, any chemotherapy within the past 6 months, previous radiotherapy within the pelvic area precluding standard chemoradiotherapy, and any contraindication for the planned treatment. All patients will be planned for six two-weekly cycles of FOLFOXIRI (5-fluorouracil, leucovorin, oxaliplatin and irinotecan) prior to chemoradiotherapy (25 × 2 Gy or 28 × 1.8 Gy with concomitant capecitabine). A resection will be performed following radiological confirmation of resectable disease after the completion of chemoradiotherapy. A watch and wait strategy is allowed in case of a clinical complete response. The primary endpoint is the CR rate, described as a pathological CR or a sustained clinical CR one year after chemoradiotherapy. The main secondary objectives are long-term oncological outcomes, radiological and pathological response, the number of resections with clear margins, treatment-related toxicity, perioperative complications, health-related costs, and quality of life.DiscussionThis trial protocol describes the MEND-IT study. The MEND-IT study aims to evaluate the CR rate after intensified chemotherapy prior to concomitant chemoradiotherapy in a homogeneous group of patients with locally advanced rectal cancer and indisputably unfavourable characteristics, defined as hr-LARC, in order to improve their prognosis.Trial registrationClinicaltrials.gov: NCT04838496, registered on 02–04-2021 Netherlands Trial Register: NL9790.Protocol versionVersion 3 dd 11–4-2022.

Combining Clinicopathology, IVIM-DWI and Texture Parameters for a Nomogram to Predict Treatment Response to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer Patients.

ObjectivesThis study aimed to create a nomogram for the risk prediction of neoadjuvant chemoradiotherapy (nCRT) resistance in locally advanced rectal cancer (LARC).MethodsClinical data in this retrospective study were collected from a total of 135 LARC patients admitted to our hospital from June 2016 to December 2020. After screening by inclusion and exclusion criteria, 62 patients were included in the study. Texture analysis (TA) was performed on T2WI and DWI images. Patients were divided into response group (CR+PR) and no-response group (SD+PD) according to efficacy assessment. Multivariate analysis was performed on clinicopathology, IVIM-DWI and texture parameters for screening of independent predictors. A nomogram was created and model fit and clinical net benefit were assessed.ResultsMultivariate analysis of clinicopathology parameters showed that the differentiation and T stage were independent predictors (OR values were 14.516 and 11.589, resp.; P<0.05). Multivariate analysis of IVIM-DWI and texture parameters showed that f value and Rads-score were independent predictors (OR values were 0.855, 2.790, resp.; P<0.05). In this study, clinicopathology together with IVIM-DWI and texture parameters showed the best predictive efficacy (AUC=0.979). The nomogram showed good predictive performance and stability in identifying high-risk LARC patients who are resistant to nCRT (C-index=0.979). Decision curve analyses showed that the nomogram had the best clinical net benefit. Ten-fold cross-validation results showed that the average AUC value was 0.967, and the average C-index was 0.966.ConclusionsThe nomogram combining the differentiation, T stage, f value and Rads-score can effectively estimate the risk of nCRT resistance in patients with LARC.

Retrospective cohort of total neoadjuvant therapy (TNT) in high-risk locally advanced rectal cancer (HR-LARC): Additional sintilimab (PD-1) in tri-modality approach.

e15604 Background: TNT is an emerging practice adapted to ensure all patients (pts) receive of systemic therapy, particularly for pts with high risk recurrence. Our previous phase II trial of TNT in MRI stratified HR-LARC demonstrated high down-staging rate and improved complete response with acceptable toxicity (manuscript under review). The aim of this retrospective cohort study was to evaluate the feasibility of sintilimab in combination with chemotherapy in TNT tri-modality treatment of pts with HR-LARC. Methods: HR-LARC pts who were given 3 cycles of sintilimab (200mg, iv, q3w) in combination with CapeOx followed by sequential long-course radiotherapy (IMRT GTV50.6 Gy/CTV 41.8 Gy/22f), 2 cycles CapeOx and surgery were enrolled from Beijing Cancer Hospital, CHN. The high risk was defined as middle to low RC (≤8cm to ARJ or 12 cm per sigmoidoscopy) with ≥1 factor from MRI features: clinical stage T3c/d-T4a/b, or N2 or MRF (+) or EMVI (+). The clinical outcomes included pathological response, major response rate (cCR+MPR), R0 resection rate, and toxicity. Results: From Feb 2019 to Oct 2020, 19 cases were identified with median distal location 4 cm (3-7), T2/T3/T4 1/15/3, N1/N2a/N2b 7/4/8, MRF+ 8/11, EMVI+ 8/11. Other characteristics were pMMR/MSS 100%, age 67y (47-78), male 57.9%, PS 1 100%, c-stage III 100% (18), median diameter of primary lesion 5.1 cm (2.1-7.5). As of 30th Dec 2020, 84.2% (16/19) received neoadjuvant therapy and completed surgical resection, with R0 resection rate 100%. One pts denied surgery and two chose watch &amp; wait since achieving cCR 10.5% (2/19). Of 16 resection pts, 13 had sphincter-sparing surgery (LAR or TaTME). One had Hartmann procedure, and two had abdominal perineal resection. The sphincter preservation rate was 84.2% (16/19). The pCR was 26.3% (5/19), and MPR was 47.3% (9/13). The major response rate was 57.9% (11/19), 4/2/13 of which completed intact TNT schema, induction and RT, and induction phase only, respectively. Treatment related adverse events (TRAE) occurred in 6 pts (31.6%) in grade (gr) 1-2 (CTCAE 5.0) without any gr 3-5 events occurred. Immune-related AEs were found in 2 pts with hypothyroidism (gr 1,2). Postoperative complications included two gr2 (Clavien-Dindo) events of anastomtic bleeding and infection. Of note, 3 pts with anastomotic stenosis got stoma reversion after dilation. Conclusions: Given the impressive response rate (57.9%), this retrospective analysis suggested a potential enhanced anti-cancer activity and good tolerability in pMMR/MSS HR-LARC from sintilimab in combination with TNT. The encouraging results warrant further evaluation of this approach in prospective trial.

ARISTOTLE: A phase III trial comparing concurrent capecitabine with capecitabine and irinotecan (Ir) chemoradiation as preoperative treatment for MRI-defined locally advanced rectal cancer (LARC).

4101 Background: Phase II studies reported high pathological complete response (pCR) rates and acceptable toxicity using irinotecan and fluoropyrimidine chemoradiation in LARC (ISRCTN:09351447). Methods: This phase III, multicentre, open-label trial funded by Cancer Research UK, randomly assigned (1:1) patients with MRI defined LARC threatening or involving resection margins without metastases, to pre-operative radiotherapy (RT) 45Gy/25 fractions combined with either capecitabine 900mg/m2(CRT) or 650 mg/m2 bd weekdays with Irinotecan iv once-weekly 60mg/m2 weeks 1-4 (IrCRT). The primary endpoint is disease-free survival (DFS). Secondary endpoints include treatment compliance, safety and pCR. Results: 75 UK sites randomised 564 eligible patients from Oct/11 to July/18; 284 to CRT and 280 to IrCRT. 370 (66%) male; median age 61 years (range:29-83). Staging in both arms was similar: mrT3 (432/564(77%), mrT4 (89/564(16%); mrCRM involved (275/564(49%); threatened ≤1mm (215/564(38%). Compared with CRT, IrCRT patients were less likely to receive 45Gy RT (207/276(75%) vs 251/283(89%), p &lt; 0.001) or receive ≥90% capecitabine dose in 188/276(68%) vs 253/283(89.4%)p &lt; 0.001). A total of 204/276(74%) received ≥90% irinotecan dose. The grade 3-4 gastrointestinal adverse event rate was 21%(58/276) with IrCRT and 12%(34/283) with CRT (p = 0.004). Patients receiving IrCRT had significantly more diarrhoea 38/276(13.8%) vs 10/283(3.5%)p &lt; 0.001) and neutropenia 27/276(9.8%) vs 3/283 (1.1%) p &lt; 0.001). Two CRT and three IrCRT patients experienced a treatment related death. 237/276(86%) IrCRT and 241/283(85%) CRT patients had surgery. The median time from end of RT to surgery(10.6 weeks), the surgical procedure APE 262/478(55%), AR 189/478(40%), Hartmann’s 10/478(2%); and the surgical complications(any event) 38%(181/478) were similar in both arms. The pCR rate is available in &gt; 95% patients and is 20.2%(46/228) for IrCRTvs.17.4%(40/230) for CRT (p = 0.45), A &gt; 84% CRM-ve resection rate is similar in both arms. Conclusions: For patients with MRI defined high risk LARC low rates of CRM involvement were observed in both arms reflecting high quality multidisciplinary care. The addition of irinotecan did not significantly improve the pCR rate, was associated with a decrease in the RT and capecitabine compliance and a higher rate of adverse events. Surgical procedure or complications were unaffected. Longer follow-up is required to assess DFS and translational data. Clinical trial information: 09351447 .

Short-course radiotherapy followed by chemotherapy before TME in locally advanced rectal cancer: The randomized RAPIDO trial.

4006 Background: Local control in locally advanced rectal cancer (LARC) has improved. However, systemic relapses remain high even with postoperative chemotherapy, possibly due to low compliance. Short-course radiotherapy (SCRT) followed by delayed surgery with, in the waiting period, chemotherapy, may lead to better compliance, downstaging and fewer distant metastases. The main objective of the international multicenter phase III RAPIDO trial is to decrease Disease-related Treatment Failure (DrTF), defined as locoregional failure, distant metastasis, a new primary colon tumor or treatment-related death, by reducing the risk of systemic relapse without compromising local control. Methods: MRI-diagnosed LARC patients with either cT4a/b, extramural vascular invasion, cN2, involved mesorectal fascia or enlarged lateral lymph nodes considered to be metastatic were randomly assigned to SCRT (5x5 Gy) with subsequent six cycles of CAPOX or nine cycles of FOLFOX4 followed by total mesorectal excision (TME) (experimental arm) or, capecitabine-based chemoradiotherapy (25-28 x 2.0-1.8 Gy) followed by TME and optional, predefined by hospital policy, postoperative eight cycles of CAPOX or twelve cycles of FOLFOX4 (standard arm). Results: Between June 2011 and June 2016, 920 patients were randomized. Pathological complete response rates were 27.7% vs 13.8% (OR 2.40 [1.70 – 3.39]; p &lt; 0.001) in the experimental and standard arms, respectively. At three years, cumulative probability of DrTF was 23.7% in the experimental arm and 30.4% in the standard arm (HR 0.76 [0.60 – 0.96]; p = 0.02). Probability at three years of distant metastasis and locoregional failure were, in the experimental and standard arms, 19.8% vs 26.6% (HR 0.69 [0.53 – 0.89]; p = 0.004) and 8.7% vs 6.0% (HR 1.45 [0.93 – 2.25]; p = 0.10), respectively. No differences in DrTF between hospitals with or without policy for postoperative chemotherapy were found (p = 0.37). Overall health ( p = 0.192), quality of life ( p = 0.125) and low anterior resection syndrome score ( p = 0.136) were comparable between the two treatment arms. Conclusions: A lower rate of DrTF, as a result of a lower rate of distant metastases, in high-risk LARC patients can be achieved with preoperative short-course radiotherapy, followed by chemotherapy and TME than by conventional chemoradiotherapy. In addition, the high pCR rate, achieved with the experimental treatment regimen can contribute to organ preservation. This treatment can be considered as a new standard of care. Clinical trial information: NCT01558921 .

Efficacy and Safety of Two Neoadjuvant Strategies With Bevacizumab in MRI-Defined Locally Advanced T3 Resectable Rectal Cancer: Final Results of a Randomized, Noncomparative Phase 2 INOVA Study

BackgroundRecurrence and distant metastases remain a significant issue in locally advanced rectal cancer (LARC). Several multimodal strategies are assessed in clinical trials. Patients and MethodsPatients with mid/low magnetic resonance imaging–defined high-risk LARC were randomized to arm A (12-week bevacizumab + FOLFOX-4 then bevacizumab–5-fluorouracil [5-FU]–radiotherapy [RT] before total mesorectal excision [TME]) or arm B (bevacizumab-5-FU–RT then TME). Long-term efficacy and safety up to 5 years’ follow-up are reported. No comparison between arms was planned. ResultsOverall, 91 patients (46 in arm A and 45 in arm B) were included. Main results have been presented previously. During the late follow-up period (> 4 weeks after surgery), 4 patients (8.7%) in arm A and 4 (8.9%) in arm B experienced grade 3/4 adverse events related to bevacizumab; the most frequent were 2 anastomotic fistulas (both in arm A) and abscesses (1 in arm A and 2 in arm B). At 5 years’ follow-up, 9 (19.6%) and 11 (24.4%) patients in arms A and B developed a fistula in the year after surgery, and 2 (4.3%) in arm A at > 1 year after surgery. Most resolved before study end. Five-year disease-free survival was 70% and 64.3% in arms A and B, respectively. Five-year overall survival was 90.5% (95% confidence interval, 76.7, 96.3) in arm A and 72.7% (95% confidence interval, 56.0, 83.9) in arm B. ConclusionNeoadjuvant bevacizumab + FOLFOX-4 may have the potential to increase survival outcomes when followed by bevacizumab–5-FU–RT and TME in LARC. Bevacizumab–5-FU–RT then TME was associated with a higher-than-projected rate of anastomotic fistulas. Further research of neoadjuvant strategies in LARC is encouraged.

Total neoadjuvant approach with FOLFOXIRI plus bevacizumab followed by chemoradiotherapy plus bevacizumab in locally advanced rectal cancer: the TRUST trial

BackgroundNeoadjuvant chemoradiotherapy (CRT) in locally advanced rectal cancer (LARC) does not achieve effective control of distant metastases. Induction chemotherapy is a promising strategy, and bevacizumab (BV) could improve the results of CRT. 5-Fluorouracil, oxaliplatin and irinotecan (FOLFOXIRI) plus BV is a treatment option in metastatic colorectal cancer. We evaluate feasibility and efficacy of neoadjuvant treatment comprising induction FOLFOXIRI plus BV followed by CRT with fluoropyrimidines plus BV. MethodsIn this phase II single-arm trial, patients node-positive or clinical T4 or high-risk T3 LARC underwent 6 cycles of induction FOLFOXIRI plus BV, followed by CRT (50.4 Gy plus concomitant capecitabine) and BV (5 mg/kg on days 1, 15 and 28). Surgery was planned 8 weeks after completion of CRT. Primary end-point was 2-year disease-free survival (DFS). ResultsWe enrolled 49 patients: All but one (withdrewing consent after enrolment) were included in the per-protocol analyses. The study met its primary end-point: 36 patients were free of recurrence at 2 years (2-y DFS: 80.45%, 95% confidence interval [CI]: 78.79–82.10). Forty-four patients underwent surgery; pathologic complete response rate was 36.4%. Forty-six patients completed induction: neutropenia (41.6%) and diarrhoea (12.5%) were main G3/4 toxicities. Forty-five patients received CRT, but the protocol was amended and the capecitabine schedule during CRT was slightly modified after 13 patients due to the incidence of G3 hand-foot syndrome and proctitis (23.1%). After amendment, no severe events during CRT were reported. ConclusionsFOLFOXIRI plus BV followed by CRT plus BV is feasible and active. Results in terms of DFS suggest that this strategy may improve distant disease control in LARC.

An experimental strategy unveiling exosomal microRNAs 486-5p, 181a-5p and 30d-5p from hypoxic tumour cells as circulating indicators of high-risk rectal cancer

ABSTRACTTumour hypoxia contributes to poor treatment outcome in locally advanced rectal cancer (LARC) and circulating extracellular vesicles (EVs) as potential biomarkers of tumour hypoxia and adverse prognosis have not been fully explored. We examined EV miRNAs from hypoxic colorectal cancer cell lines as template for relevant miRNAs in LARC patients participating in a prospective biomarker study (NCT01816607). Five cell lines were cultured under normoxia (21% O2) or hypoxia (0.2% O2) for 24 h, and exosomes were isolated by differential ultracentrifugation. Using a commercial kit, exosomes were precipitated from 24 patient plasma samples collected at the time of diagnosis. Exosome size distribution and protein cargo were determined by cryo-electron microscopy, nanoparticle tracking analysis, immunoblotting and flow cytometry. The vesicles harboured strong cell line-specific miRNA profiles with 35 unique miRNAs differentially expressed between hypoxic and normoxic cells. Six of these miRNAs were considered candidate-circulating markers of tumour hypoxia in the patients based on the frequency or magnitude of variance in hypoxic versus normoxic cell line experiments and prevalence in patient plasma. Of these, low plasma levels of exosomal miR-486-5p and miR-181a-5p were associated with organ-invasive primary tumour (p = 0.029) and lymph node metastases (p = 0.024), respectively, both attributes of adverse LARC prognosis. In line with this, the plasma level of exosomal miR-30d-5p was elevated in patients who experienced metastatic progression (p = 0.036). Our strategy confirmed that EVs from colorectal cancer cell lines were exosomes containing the oxygen-sensitive miRNAs 486-5p, 181a-5p and 30d-5p, which were retrieved as circulating markers of high-risk LARC.

BACCHUS: A randomised non-comparative phase II study of neoadjuvant chemotherapy (NACT) in patients with locally advanced rectal cancer (LARC)

BackgroundChemoradiation (CRT) or short-course radiotherapy (SCRT) are standard treatments for locally advanced rectal cancer (LARC). We evaluated the efficacy/safety of two neoadjuvant chemotherapy (NACT) regimens as an alternative prior to total mesorectal excision (TME). Methods/designThis multi-centre, phase II trial in patients with magnetic resonance imaging (MRI) defined high-risk LARC (>cT3b, cN2+ or extramural venous invasion) randomised patients (1:1) to FOLFOX + Bevacizumab (Arm 1) or FOLFOXIRI + bevacizumab (Arm 2) every 14 days for 6 cycles prior to surgery. Patients were withdrawn if positron emission tomography (PET) standardised uptake value (SUV) after 3 cycles failed to decrease by >30% or increased compared to baseline. Primary endpoint was pathological complete response rate (pCR). Secondary endpoints included adverse events (AE) and toxicity. Neoadjuvant rectal (NAR) scores based on “T” and “N” downstaging were calculated. FindingsTwenty patients aged 18–75 years were randomised. The trial stopped early because of poor accrual. Seventeen patients completed all 6 cycles of NACT. One stopped due to myocardial infarction, 1 poor response on PET (both received CRT) and 1 committed suicide. 11 patients had G3 AE, 1 G4 AE (neutropenia), and 1 G5 (suicide). pCR (the primary endpoint) was 0/10 for Arm 1 and 2/10 for Arm 2 i.e. 2/20 (10%) overall. Median NAR score was 14·9 with 5 (28%), 7 (39%), and 6 (33%) having low, intermediate, or high scores. Surgical morbidity was acceptable (1/18 wound infection, no anastomotic leak/pelvic sepsis/fistulae). The 24-month progression-free survival rate was 75% (95% CI: 60%–85%). InterpretationThe primary endpoint (pCR rate) was not met. However, FOLFOXIRI and bevacizumab achieved promising pCR rates, low NAR scores and was well-tolerated. This regimen is suitable for testing as the novel arm against current standards of SCRT and/or CRT in a future trial.

Long-Term Outcome of Oxaliplatin and Capecitabine (XELOX) Concomitant with Neoadjuvant Radiotherapy and Extended to the Resting Period in High Risk Locally Advanced Rectal Cancer

Purpose: This study aimed at investigating the long-term outcomes of oxaliplatin and capecitabine (XELOX) administered concurrently with preoperative radiation and extended to the resting period in patients with high-risk locally advanced rectal cancer (LARC).Methods: From January 2010 to December 2013, 45 patients were recruited. Study treatment consisted two cycles of XELOX regimen concomitant with preoperative radiation and then followed by an additional cycle of XELOX regimen between completion of neoadjuvant radiotherapy and surgery. Disease-free survival (DFS) time and overall survival (OS) time were analyzed.Results: The median follow-up was 51 months. Twelve (26.7%) patients developed local recurrence or distant metastasis, including 10 (22.2%) patients developing distant metastasis only, 1 (2.2%) patient local recurrence only, and 1 (2.2%) patient both local recurrence and distant metastasis. The estimated 3-year DFS and OS was 75.5% (95% CI, 63.0%-88.0%) and 88.6% (95% CI, 98.0%-79.2%), respectively. Receiving adjuvant chemotherapy was a significant predictor for DFS, with hazard ratio 0.24 (95% CI: 0.08-0.74).Conclusion: This intensified strategy with oxaliplatin and capecitabine (XELOX) administered concomitantly with neoadjuvant radiotherapy and then extended to the resting period in high-risk LARC patients is efficient. The long-term outcome is promising. Further study of this strategy is warranted.

PAN-EX: a pooled analysis of two trials of neoadjuvant chemotherapy followed by chemoradiotherapy in MRI-defined, locally advanced rectal cancer

EXPERT and EXPERT-C were phase II clinical trials of neoadjuvant chemotherapy (NACT) followed by chemoradiotherapy (CRT) in high-risk, locally advanced rectal cancer (LARC). We pooled individual patient data from these trials. The primary objective was overall survival (OS) in the intention-to-treat (ITT) population. Prognostic factors were also analysed. A total of 269 patients were included. Of these, 91.1% completed NACT, 88.1% completed CRT and 240 (89.2%) underwent curative surgery (R0/R1). After a median follow-up of 71.9 months, 5-year progression-free survival (PFS) and OS were 66.4% and 73.3%, respectively. In the group of R0/R1 resection patients, 5-year relapse-free survival (RFS) and OS were 71.6% and 77.2%, respectively, with local recurrence occurring in 5.5% and distant metastases in 20.6% of cases. Significant prognostic factors after multivariate analyses included age, tumour grade and MRI extramural venous invasion (mrEMVI) at baseline, MRI tumour regression grade (mrTRG) after CRT, ypT stage after surgery and adherence to study treatment. mrTRG after NACT was associated with PFS (P = 0.002) and OS (P = 0.018) and appeared to stratify patients based on the incremental benefit from sequential CRT. Among the outcome measures considered, in the subgroup of R0/R1 resection patients, ypT and ypStage had the highest predictive accuracy for RFS (concordance index: 0.6238 and 0.6252, respectively) and OS (concordance index: 0.6094 and 0.6132, respectively). Administering NACT before CRT could be a potential strategy for high-risk LARC. In this setting, mrTRG after CRT is an independent prognostic factor, while mrTRG after NACT should be tested as a parameter for treatment selection in trials of NACT ± CRT. ypT stage may be a valuable surrogate end point for future phase II trials investigating intensified neoadjuvant treatments in similar patient populations.

Early results of multicenter phase II trial of perioperative oxaliplatin and capecitabine without radiotherapy for high-risk rectal cancer: CORONA I study

BackgroundsPerioperative introduction of developed chemotherapy into the treatment strategy for locally advanced rectal cancer (LARC) may be a promising option. However, the most prevalent treatment for high-risk LARC remains preoperative chemoradiotherapy (CRT) in Western countries. Patients and methodsA phase II trial was undertaken to evaluate safety and efficacy of perioperative XELOX without radiotherapy (RT) for patients with high-risk LARC. Patients received 4 cycles of XELOX before and after surgery, respectively. Primary endpoint was disease-free survival. ResultsWe enrolled 41 patients between June 2012 and April 2014. The completion rate of the preoperative XELOX was 90.3%. Twenty-nine patients (70.7%) could start postoperative XELOX, 15 of these patients (51.7%) completed 4 cycles. Allergic reaction to oxaliplatin was experienced by 5 patients (17.2%) during postoperative XELOX. One patient received additional RT after preoperative XELOX. Consequently, the remaining 40 patients underwent primary resection. Major complications occurred in 6 of 40 patients (15.0%). Pathological complete response (pCR) rate was 12.2%, and good tumor regression was exhibited in 31.7%. N down-staging (cN+ to ypN0) and T down-staging were detected in 56.7% and 52.5%, respectively. Clinical T4 tumor was a predictor of poor pathological response (p < 0.001). ConclusionsWe could show the favorable pCR rate after preoperative XELOX alone. However, the T and N down-staging rate was likely to be insufficient. When tumor regression is essential for curative resection, the use of preoperative CRT is likely to be recommended. For patients with massive LN metastasis, the additional Bev to NAC might be a promising option.

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

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. 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. 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. 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.

Prognostic effect of a single nucleotide polymorphism (SNP) in MIR608 in patients with high-risk locally advanced rectal cancer (LARC): Results of the EXPERT-C trial.

581 Background: An association between rs4919510, a SNP of mir-608, and prognosis of patients with colorectal cancer has been reported. However, no studies have analysed the role of this SNP in LARC. We conducted a pharmacogenomic analysis of rs4919510 in EXPERT-C, a randomised phase II trial of neoadjuvant CAPOX followed by chemoradiotherapy, surgery and adjuvant CAPOX ± cetuximab in high-risk LARC. Methods: SNP analysis was performed on DNA extracted from tumour tissue. Kaplan-Meier method and Cox regression analysis were used to calculate survival estimates and compare treatment arms. Results: A total of 155/164 (94.5%) patients had tumours assessable for rs4919510 genotyping. 95 (61.3%) were homozygous for CC, 55 (35.5%) heterozygous (CG) and 5 (3.2%) homozygous for GG with no deviation from the Hardy-Weinberg equilibrium (p=0.379). Genotypes were evenly distributed in the two treatment groups and no association with baseline clinico-pathological characteristics or tumour molecular status (including RAS) was observed. Complete response did not differ according to the tumour genotype in the entire population (14.7% for CC, 13.3% for CG/GG) and was not influenced by treatment (12.0% for CC and 14.3% for CG/GG in CAPOX, 17.8% for CC and 12.5% for CG/GG in CAPOX-C) (all p values&gt;0.05). Median follow-up was 64.9 months. In the CAPOX arm the 5-yr PFS and OS rates were 54.6% and 60.7% for CC and 82.0% and 82.1% for CG/GG, respectively (HR PFS 0.13, 95% CI: 0.12-0.83, p=0.02, HR OS 0.38, 95% CI: 0.14-1.01, p=0.05). In the CAPOX-C arm the same survival figures were 73.2% and 82.2% for CC and 64.6% and 73.1% for CG/GG (HR PFS 1.38, 95% CI: 0.61-3.13, p=0.44, HR OS 1.34, 95% CI: 0.52-3.48, p=0.55). An interaction was found between study treatment and rs4919510 genotype for both PFS (p=0.02) and OS (p=0.07). Conclusions: This is the first study investigating rs4919510 in LARC. We found that the CC genotype was associated with worse prognosis compared to the CG/GG genotype in patients treated with chemotherapy alone but not in those treated with cetuximab. The addition of cetuximab to chemotherapy may mitigate the unfavourable prognostic associated with the CC genotype.

Neoadjuvant Chemotherapy First, Followed by Chemoradiation and Then Surgery, in the Management of Locally Advanced Rectal Cancer

Standard therapy for locally advanced rectal cancer (LARC) is preoperative chemoradiotherapy and postoperative chemotherapy. At Memorial Sloan-Kettering Cancer Center (MSKCC) the authors began offering FOLFOX (5-fluorouracil, leucovorin, and oxaliplatin) as initial treatment for patients with high-risk LARC to target micrometastases while treating the primary tumor. The purpose of this study is to report the safety and efficacy of initial FOLFOX given before chemoradiotherapy on tumor downsizing and pathologic complete response (pathCR) in LARC. The records of patients with stage II/III rectal cancer treated at MSKCC between 2007 and 2012 were reviewed. Of approximately 300 patients with LARC treated at MSKCC, 61 received FOLFOX as initial therapy. Of these 61 patients, 57 received induction FOLFOX (median 7 cycles) followed by chemoradiation, and 4 experienced an excellent response, declined chemoradiation, and underwent total mesorectal excision (TME). Twelve of the 61 patients did not undergo TME: 9 had a complete clinical response (CCR), 1 declined despite persistent tumor, 1 declined because of comorbidities, and 1 developed metastatic disease. Among the 61 patients receiving initial FOLFOX, 22 (36%) had either a pathCR (n=13) or a CCR (n=9). Of the 49 patients who underwent TME, all had R0 resections and 23 (47%) had tumor response greater than 90%, including 13 (27%) who experienced a pathCR. Of the 28 patients who received all 8 cycles of FOLFOX, 8 experienced a pathCR (29%) and 3 a CCR (11%). No serious adverse events occurred that required a delay in treatment during FOLFOX or chemoradiation. FOLFOX and chemoradiation before planned TME results in tumor regression, a high rate of delivery of planned therapy, and a substantial rate of pathCRs, and offers a good platform for nonoperative management in select patients.

Oxaliplatin and capecitabine concomitant with neoadjuvant radiotherapy and extended to the resting period in high risk locally advanced rectal cancer

Conventional neoadjuvant chemoradiotherapy (CRT) is suboptimal for systemic control in locally advanced rectal cancer (LARC). To improve systemic control, we developed an alternative approach in which an intensified oxaliplatin and capecitabine (XELOX) chemotherapy regimen was administered concomitantly with radiation and extended to the resting period (consolidation chemotherapy) for high-risk LARC. The aim of the current study was to evaluate the short-term efficacy and toxicity of this strategy. Patients with high-risk LARC were treated with CRT. Two cycles of XELOX were administered concomitantly with radiation. Thereafter, an additional cycle of the same regimen was administered during the resting period after completion of CRT. Tumor response, toxicities and surgical complications were recorded. This study includes 36patients treated with the above strategy. All patients completed the planned concurrent CRT. Because of grade3 toxicities, 2patients were unable to complete the additional chemotherapy. Grade3 toxicities were leucopenia (2.8 %), diarrhea (2.8 %) and radiodermatitis (2.8 %). All patients underwent optimal surgery with total mesorectal excision (TME) and a sphincter-saving procedure was performed in 27patients (75 %). There was no perioperative mortality. Postoperative complications developed in 7patients (19.4 %). Pathologic complete regression (pCR),"nearly pCR" (major regression), and moderate or minimal regression were achieved in 13(36.1 %), 16(44.4 %), and 7patients (19.5 %), respectively. The preliminary results suggest that a XELOX regimen initially administered concomitantly with radiotherapy and then extended to the resting period in high-risk LARC patients is well tolerated. The strategy is highly effective in terms of pCR and nearly pCR rates, and thus warrants further investigation.