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

A pilot study on the safety and efficacy of neoadjuvant chemo‑adoptive immunotherapy for locally advanced rectal cancer

The safety and efficacy of combination therapy of immune cell therapy and chemotherapy [chemo-adoptive immunotherapy (CAIT)] for patients with stage IV or recurrent colorectal cancer have been reported. In the present study, the safety and efficacy of neoadjuvant CAIT were investigated for preoperative therapy of locally advanced rectal cancer. The study included patients with cT3/T4 or cN (+) rectal adenocarcinoma scheduled for curative surgery. Six patients who consented to participate in the current study were selected as subjects. Neoadjuvant CAIT involves administration of activated autologous lymphocytes, αβ T cells, and mFOLFOX6 every 2 weeks for six courses, followed by surgery 4-6 weeks thereafter. Common Terminology Criteria for Adverse Events grade 3 neutropenia was observed in one patient. Neoadjuvant CAIT and curative surgery were performed on all the patients. The confirmed response rate was 67%. Downstaging was confirmed in five patients (83%). Regarding histological effects, two patients were grade 1a and four were grade 2. Regarding immunological reactions, both CD4+ and CD8+ T cell infiltration rates increased after treatment in three patients on tumor-infiltrating lymphocyte (TIL) analysis. In peripheral blood analysis, the total lymphocyte count was maintained in all patients, and the CD8+ T cell count increased by ≥3 times on the pretreatment count in two patients but may not be associated with changes in TILs. During the median postoperative follow-up duration of 24 months, liver and lung metastases occurred in one patient, but all patients survived. In conclusion, neoadjuvant CAIT (αβ T cells + mFOLFOX6) can be safely administered for the treatment of advanced rectal cancer. Verification of the efficacy of comprehensive immune cell therapy, especially the induction of antitumor immunity for the prevention of recurrence, will be maintained. The current study is registered with the Japan Registry of Clinical Trials (jRCT; ID, jRCTc030190248; January 21, 2019).

Neoadjuvant chemotherapy (CAPOX) alone for low- and intermediate-risk stage II/III rectal cancer: Long-term follow-up of a prospective single-arm study

BACKGROUND

Stratified treatment has been recommended for rectal cancer. Our previous multicenter randomized trial showed that low-/intermediate-risk rectal cancer patients did not benefit much from neoadjuvant chemoradiotherapy. In our phase II study, we found that stage II/III rectal cancer patients with low-/intermediate risks can be managed by neoadjuvant chemotherapy alone and achieve a good response. The current study aimed to report the long-term survival outcomes in the expanded phase II trial.

METHOD

Consecutive patients diagnosed with mid-low stage II/III rectal cancer with low/intermediate risk factors were included. Four cycles of neoadjuvant chemotherapy (CAPOX) were given, and MRI was used for tumour response detection. The primary endpoint was disease-free survival. The secondary endpoints were tumour response to NCT, tumour-related death, and overall survival.

RESULTS

This study enrolled 121 eligible patients. The good tumour response rate based on MRI was 82.6 %, with a pathological complete response (pCR) rate of 18.3 %. The disease-free survival rate was 82.6 %, and the overall survival rate was 96.7 % after a median follow-up time of 40 months. Two patients (1.7 %) suffered local recurrence, and 15 patients (12.4 %) suffered distant metastasis. The median disease-free survival and overall survival were 37 (9-60) and 40 (16-60) months, respectively. Tumour longitudinal length reduction and tumour regression grade on MRI were identified as predictors for poor tumour response to neoadjuvant chemotherapy.

CONCLUSION

In stage II/III rectal cancer patients with low-/intermediate risks, neoadjuvant chemotherapy alone may result in an acceptable tumour response and disease-free survival. Tumour response might be predicted early.

Treatment response prediction of neoadjuvant chemotherapy for rectal cancer by deep learning of colonoscopy images

In current clinical practice, several treatment methods, including neoadjuvant therapy, are being developed to improve overall survival or local recurrence rates for locally advanced rectal cancer. The response to neoadjuvant therapy is usually evaluated using imaging data collected before and after preoperative treatment or postsurgical pathological diagnosis. However, there is a need to accurately predict the response to preoperative treatment before treatment is administered. The present study used a deep learning network to examine colonoscopy images and construct a model to predict the response of rectal cancer to neoadjuvant chemotherapy. A total of 53 patients who underwent preoperative chemotherapy followed by radical resection for advanced rectal cancer at the Osaka University Hospital between January 2011 and August 2019 were retrospectively analyzed. A convolutional neural network model was constructed using 403 images from 43 patients as the learning set. The diagnostic accuracy of the deep learning model was evaluated using 84 images from 10 patients as the validation set. The model demonstrated a sensitivity, specificity, accuracy, positive predictive value and area under the curve of 77.6% (38/49), 62.9% (22/33), 71.4% (60/84), 74.5% (38/51) and 0.713, respectively, in predicting a poor response to neoadjuvant therapy. Overall, deep learning of colonoscopy images may contribute to an accurate prediction of the response of rectal cancer to neoadjuvant chemotherapy.

Comparison of the pathological response to 2 or 4 cycles of neoadjuvant CAPOX in II/III rectal cancer patients with low/intermediate risks: study protocol for a prospective, non-inferior, randomized control trial (COPEC trial)

BACKGROUND

For patients with low- and intermediate-risk stage II/III rectal cancer, current studies have reached a consensus that preoperative radiotherapy may be dispensed with, and neoadjuvant chemotherapy (NCT) alone might achieve an accepted local control. Our previous phase II study has evidenced that the morphological response of NCT could be better judged at a relatively early stage. Low- and intermediate-risk stage II/III rectal cancer patients could achieve a high rate of tumor shrinkage and downgrade after only 4 cycles of NCT and obvious tumor morphological changes could be observed after 2 cycles of NCT. However, there is still a lack of more detailed stratification and evidence for pathological criteria. The aim of the present study (comparison of the pathological response to 2 or 4 cycles of neoadjuvant CAPOX in II/III rectal cancer patients with low/intermediate risks, COPEC trial) is to determine the pathological tumor regression grade (pTRG) rate of 2 or 4 cycles of NCT in low- and intermediate-risk stage II/III rectal cancer and verify the feasibility of early identification of chemotherapy-insensitive population.

METHODS/DESIGN

This is a multicenter, prospective, non-inferior, randomized controlled trial (RCT) initiated by West China Hospital of Sichuan University and designed to be conducted in fourteen hospitals around China. Eligible patients will be centrally randomized into 2 or 4 cycles of CAPOX in a 1:1 ratio using the central automated randomization system offered by the O-trial online system ( https://plus.o-trial.com/ ) and accept total mesorectal excision after 2 or 4 cycles of CAPOX (oxaliplatin 130 mg/m², once daily on day 1, every 21 days and capecitabine 1000 mg/m², twice daily on days 1 to 14, every 21 days). The primary endpoint is the proportion of patients with pathological no-tumor regression (pTRG 3), which is determined postoperatively by each sub-center and verified by the primary center.

DISCUSSION

COPEC trial is designed to verify that the preoperative CAPOX chemotherapy for low- and intermediate-risk stage II/III rectal cancer could achieve a good response judgment after 2 cycles and obtain the tumor pathological response rate after 2 cycles of CAPOX. We hope the COPEC trial could help in establishing a consensus standard of low- and intermediate-risk rectal cancer and the early identification of stage II/III rectal patients with low- and intermediate-risk who are poorly responding to NCT.

TRIAL REGISTRATION

Clinicaltrial.gov NCT04922853. Registered on June 4, 2021.

Neoadjuvant Chemotherapy With CAPOX Versus Chemoradiation for Locally Advanced Rectal Cancer With Uninvolved Mesorectal Fascia (CONVERT): Initial Results of a Phase III Trial

OBJECTIVE

To compare neoadjuvant chemotherapy (nCT) with CAPOX alone versus neoadjuvant chemoradiotherapy (nCRT) with capecitabine in locally advanced rectal cancer (LARC) with uninvolved mesorectal fascia (MRF).

BACKGROUND DATA

nCRT is associated with higher surgical complications, worse long-term functional outcomes, and questionable survival benefits. Comparatively, nCT alone seems a promising alternative treatment in lower-risk LARC patients with uninvolved MRF.

METHODS

Patients between June 2014 and October 2020 with LARC within 12 cm from the anal verge and uninvolved MRF were randomly assigned to nCT group with 4 cycles of CAPOX (Oxaliplatin 130 mg/m2 IV day 1 and Capecitabine 1000 mg/m2 twice daily for 14 d. Repeat every 3 wk) or nCRT group with Capecitabine 825 mg/m² twice daily administered orally and concurrently with radiation therapy (50 Gy/25 fractions) for 5 days per week. The primary end point is local-regional recurrence-free survival. Here we reported the results of secondary end points: histopathologic response, surgical events, and toxicity.

RESULTS

Of the 663 initially enrolled patients, 589 received the allocated treatment (nCT, n=300; nCRT, n=289). Pathologic complete response rate was 11.0% (95% CI, 7.8-15.3%) in the nCT arm and 13.8% (95% CI, 10.1-18.5%) in the nCRT arm ( P =0.33). The downstaging (ypStage 0 to 1) rate was 40.8% (95% CI, 35.1-46.7%) in the nCT arm and 45.6% (95% CI, 39.7-51.7%) in the nCRT arm ( P =0.27). nCT was associated with lower perioperative distant metastases rate (0.7% vs. 3.1%, P =0.03) and preventive ileostomy rate (52.2% vs. 63.6%, P =0.008) compared with nCRT. Four patients in the nCT arm received salvage nCRT because of local disease progression after nCT. Two patients in the nCT arm and 5 in the nCRT arm achieved complete clinical response and were treated with a nonsurgical approach. Similar results were observed in subgroup analysis.

CONCLUSIONS

nCT achieved similar pCR and downstaging rates with lower incidence of perioperative distant metastasis and preventive ileostomy compared with nCRT. CAPOX could be an effective alternative to neoadjuvant therapy in LARC with uninvolved MRF. Long-term follow-up is needed to confirm these results.

Essential updates 2020/2021: Advancing precision medicine for comprehensive rectal cancer treatment

In the paradigm shift related to rectal cancer treatment, we have to understand a variety of new emerging topics to provide appropriate treatment for individual patients as precision medicine. However, information on surgery, genomic medicine, and pharmacotherapy is highly specialized and subdivided, creating a barrier to achieving thorough knowledge. In this review, we summarize the perspective for rectal cancer treatment and management from the current standard-of-care to the latest findings to help optimize treatment strategy.

Prolonged neoadjuvant chemotherapy without radiation versus total neoadjuvant therapy for locally advanced rectal cancer: A propensity score matched study

Background

Although neoadjvuant chemoradiotherapy (CRT) improves the local control rate of locally advanced rectal cancer (LARC), it fails to significantly improve disease-free survival (DFS) and overall survival (OS). We explored the efficacy of prolonged neoadjuvant chemotherapy (pNCT) without radiation and compared this schema with total neoadjuvant therapy (TNT).

Material and methods

Patients diagnosed with LARC and received TNT (4 cycles of induction CapeOX/FOLFOX followed with CRT) or pNCT (6~8 cycles of CapeOX/FOLFOX) between June 2016 and October 2021 were retrospective analyzed. All patients underwent total mesorectal excision (TME). A 1:1 propensity score match was performed to adjust baseline potential confounders. The tumor response, toxicity, recurrence-free survival (RFS) and OS were observed.

Results

A total of 184 patients with 92 patients in each group were finally enrolled. The median follow-up time was 35 months. TNT showed better pathological complete response (pCR) rate (25.0% vs 16.3%) and objective regression rate (73.9% vs 59.8%) than pNCT. TNT and pNCT produce similar 3-year RFS and OS rates in patients with mid-to-upper rectal cancer. TNT was associated with improved tumor responsiveness in all patients and improved 3-year RFS rates in those with low rectal cancer.

Conclusion

pNCT is an option for patients with mid-to-upper rectal cancer, but radiation is still necessary for low rectal cancer. To determine optimal schema for neoadjuvant therapy and patient selection, additional randomized controlled studies are needed.

A phase II study of neoadjuvant capecitabine, oxaliplatin, and irinotecan (XELOXIRI) in patients with locally advanced rectal cancer

Purpose

Addition of perioperative multi-agent chemotherapy to the treatment strategy for locally advanced rectal cancer (LARC) may be a promising option. We conducted a phase II study to evaluate the safety and efficacy of capecitabine combined with oxaliplatin and irinotecan (XELOXIRI) as triplet neoadjuvant chemotherapy in patients with LARC.

Methods

Patients received neoadjuvant irinotecan and oxaliplatin and capecitabine and then underwent total mesorectal excision. The primary study endpoint was the pathological complete response (pCR) rate.

Results

Between June 2013 and December 2016, 55 patients were enrolled in the study. Forty-two (77.8%) of 54 completed the study protocol. The pCR rate was 7.7% (95% CI 3.0% to 18.2%). The 3-year local recurrence rate was 3.9%, the 3-year disease-free survival (DFS) rate was 77.3, and the 3-year overall survival rate was 96.0%.

Conclusion

XELOXIRI neoadjuvant chemotherapy appears to be feasible and efficacious for patients with LARC. Although neoadjuvant XELOXIRI alone did not yield our expected pCR rate, the local recurrence rate, 3-year DFS, and measures of safety met current standards.

Quality of life in a randomized trial comparing two neoadjuvant regimens for locally advanced rectal cancer-INCAGI004

BACKGROUND

Neoadjuvant chemoradiotherapy (neoCRT) followed by surgery is the standard of care for locally advanced rectal cancer (LARC), but the emergence of different drug regimens may result in different response rates. Good clinical response translates into greater sphincter preservation, but quality of life (QOL) may be impaired after treatment due to chemoradiotherapy and surgical side effects.

OBJECTIVE

To prospectively evaluate the impact of clinical response and surgical resection on QOL in a randomized trial comparing two different neoCRT regimens.

METHODS

Stage II and III rectal cancer patients were randomized to receive neoCRT with either capecitabine (group 1) or 5-Fu and leucovorin (group 2) concomitant to long-course radiotherapy. Clinical downstaging was accessed using MRI 6-8 weeks after treatment. EORTCs QLQ-C30 and CR38 were applied before treatment (T0), after neoCRT (T1), after rectal resection (T2), early after adjuvant chemotherapy (T3), and 1 year after the end of treatment or stoma closure (T4). The Wexner scale was used for fecal incontinence evaluation at T4. A C30SummaryScore (Geisinger and cols.) was calculated to compare QOL results.

RESULTS

Thirty-two patients were assigned to group 1 and 31 to group 2. Clinical downstaging occurred in 70.0% of group 1 and 53.3% of group 2 (p = 0.288), and sphincter preservation was 83.3% in group 1 and 80.0% in group 2 (p = 0.111). No significant difference in QOL was detected when comparing the two treatment groups after neoCRT using QLQ-C30. However, the CR38 module detected differences in micturition problems (15.3 points), gastrointestinal problems (15.3 points), defecation problems (11.8 points), and sexual satisfaction (13.3 points) favoring the capecitabine group. C30SummaryScore detected significant improvement comparing T0 to T1 and deterioration comparing T1 to T2 (p = 0.025). The mean Wexner scale score was 9.2, and a high score correlated with symptoms of diarrhea and defecation problems at T4.

CONCLUSIONS

QOL was equivalent between groups after neoCRT except for micturition problems, gastrointestinal problems, defecation problems, and sexual satisfaction favoring the capecitabine arm after. The overall QOL using the C30SummaryScore was improved after neoCRT, but decreased following rectal resection, returning to basal levels at late evaluation. Fecal incontinence was high after sphincter preservation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03428529.

Short-Term Outcomes with Standardized Transperineal Minimally Invasive Abdominoperineal Excision for Rectal Cancer

BACKGROUND

Transperineal abdominoperineal excision (TpAPE) is an emerging approach for low rectal cancers but is technically challenging. Based on an anatomical study we conducted previously, we have standardized the TpAPE procedure. Here, we aimed to validate the feasibility of the standardized TpAPE by investigating the short-term outcomes.

METHODS

From January 2018 to November 2020, a total of 405 patients underwent laparoscopic or robotic rectal resection for rectal cancer in our institution. For the current study, we analyzed data for the 31 patients who underwent TpAPE. The abdominal phase was performed synchronously with the perineal phase using either a laparoscopic or robotic approach. Short-term outcomes included operative and pathological results.

RESULTS

Of the 31 cases, we identified anterior quadrant tumor invasion in 21. Most of the cases were advanced, with 6 staged as cT3 and 20 as T4. Of the 27 cases not involving distant metastasis, neoadjuvant therapy was performed in 19. No inadvertent rectal perforation or urethral injury was found intraoperatively. The median procedural duration to specimen removal was 250 min (interquartile range, 204-287), and the median intraoperative blood loss was 10 ml (interquartile range, 5-40). Regarding postoperative complications, perineal wound infection developed in 11 cases. A positive circumferential resection margin was found in 3, corresponding to the positive rate of 9.7%. These three cases were among the first 12 cases involving standardized TpAPE.

CONCLUSIONS

The current results indicate that TpAPE can be performed safely and might represent a useful option for low rectal cancer resection.

Early response to upfront neoadjuvant chemotherapy (CAPOX) alone in low- and intermediate-risk rectal cancer: a single-arm phase II trial

BACKGROUND

With local recurrence of rectal cancer continuing to decrease, distant recurrence is becoming a major concern, especially for patients with low- and intermediate-risk stage II/III rectal cancer. Therefore, a new treatment strategy is warranted for these patients. This single-arm phase II trial aimed to assess the effect of neoadjuvant chemotherapy (NCT) in low- and intermediate-risk stage II/III rectal cancer and explore candidate radiological and clinical parameters for early prediction of tumour response after two cycles of CAPOX.

METHODS

Patients with mid-low stage II/III rectal cancer with low and intermediate risk were examined. The primary outcome was defined as a clinicopathological response by integrating tumour longitudinal length reduction (TLLR) on MRI into pathological tumour regression grade (TRG). After completing NCT, patients with TRG0-2 and TRG3 with a TLLR rate greater than 30 per cent were considered to be responders. Secondary outcomes included pathological complete response (pCR), adverse events and local and distant recurrence.

RESULTS

This study enrolled 61 eligible patients. No patient was converted to neoadjuvant chemoradiotherapy owing to tumour progression. The clinicopathological response and pCR rates were 78.7 and 21.3 per cent respectively. After two cycles of CAPOX, TLLR, TRG on MRI, and mucosal lesion regression grade on endoscopy had potential discriminative ability (area under the curve greater than 0.7) for predicting both clinicopathological and pathological response.

CONCLUSION

NCT alone achieves good tumour response rates in patients with low- and intermediate-risk stage II/III rectal cancer, and predicting tumour response to NCT is feasible at an early treatment phase.

REGISTRATION NUMBER

NCT03666442 (http://www.clinicaltrials.gov).

MRI-detected extramural vascular invasion potentiates the risk for pathological metastasis to the lateral lymph nodes in rectal cancer

PURPOSE

Multidisciplinary treatment for locally advanced rectal cancer requires an accurate assessment of the risk of metastasis to the lateral lymph nodes (LNs). We herein aimed to stratify the risk of pathological metastasis to lateral LNs based on the preoperatively detected malignant features.

METHODS

All patients with rectal cancer who underwent surgery from January 2016 to July 2020 were identified. We recorded the TNM factors; perirectal and lateral LN sizes; and MRI findings, including mesorectal fascia involvement, extramural vascular invasion (EMVI), tumor site, and tumor distance from the anal verge.

RESULTS

101 patients underwent rectal resection with lateral lymph node dissection, of whom 16 (15.8%) exhibited pathological metastases to the lateral LNs. Univariate analyses demonstrated that lateral LN metastasis was significantly correlated with mrEMVI positivity (p = 0.0023) and a baseline lateral LN short-axis length of ≥ 5 mm (p < 0.0001). These significant associations were confirmed by a multivariate analysis (p = 0.0254 and 0.0027, respectively). The lateral LN metastasis rate was as high as 44% in cases bearing both risk factors, compared to 0% in cases lacking both risk factors.

CONCLUSION

The results elucidated in this study may contribute to risk stratification, which can be used when determining the indications for lateral lymph node dissection.

Neoadjuvant Chemotherapy without Radiation in Colorectal Cancer

In colon cancer, primary surgery followed by postoperative chemotherapy represents the standard of care. In rectal cancer, the standard of care is preoperative radiotherapy or chemoradiation, which significantly reduces local recurrence but has no impact on subsequent metastatic disease or overall survival. The administration of neoadjuvant chemotherapy (NACT) before surgery can increase the chance of a curative resection and improves long-term outcomes in patients with liver metastases. Hence, NACT is being explored in both primary rectal and colon cancers as an alternative strategy to shrink the tumor, facilitate a curative resection, and simultaneously counter the risk of metastases. Yet, this lack of clarity regarding the precise aims of NACT (downstaging, maximizing response, or improving survival) is hindering progress. The appropriate cytotoxic agents, the optimal regimen, the number of cycles, or duration of NACT prior to surgery or in the postoperative setting remains undefined. Several potential strategies for integrating NACT are discussed with their advantages and disadvantages.

Neo-adjuvant chemotherapy alone for the locally advanced rectal cancer: a systematic review

Neo-adjuvant chemoradiation (NA-CRT) is the standard of management for the locally advanced rectal cancer (LARC), achieving very low rates of local recurrence (LR). However, NA-CRT fails to control distant recurrence and improve survival, whilst it is associated with increased postoperative morbidity and increased acute and late toxicity. In recent years, neo-adjuvant chemotherapy (NACTx) appears in the literature as an alternative to NA-CRT in patients with LARC. In the present study, the authors review all current evidence on the specific subject. Following a systematic search of the literature, 25 studies were identified reporting on short- or long-term outcomes of NACTx for LARC. Seventeen studies were prospective or retrospective series, and 8 comparative. Of the comparative studies, one was a randomized control trial (RCT) comparing NACTx to NA-CRT and to the combination of NACTx/NA-CRT, and another a non-randomized study comparing NACTx to NA-CRT. Chemotherapeutic regimens were 5-fluoropyrimidine and oxaliplatin based. In some of them, irinotecan or/and bevacizumab was added. A pooled analysis showed that NACTx is associated with a mean anastomotic leak rate of 6.8%. In the RCT, postoperative morbidity and overall toxicity was significantly less in the NACTx group. Mean T downstaging (ypStage 0-I) was 49.6%, mean N downstaging 69.6% and mean pathologic complete response (pCR) 10.7%. The RCT showed an inferior pCR rate after NACTx than after NA-CRT, but similar rates of T downstaging. Mean LR was 8.6% and mean distant recurrence 17.2%. Satisfactory survival rates are reported by several studies. NACTx seems to be an alternative to NA-CRT for patients with LARC, associated with low anastomotic leak, adequate tumour downstaging, low LR and rather high survival rates. Further data deriving from high-quality studies are necessary to assess safety and efficacy of NACTx as a substitute to NA-CRT, for at least a subset of patients with LARC.

Importance of the neoadjuvant rectal (NAR) score to the outcome of neoadjuvant chemotherapy alone for locally advanced rectal cancer

PURPOSE

The neoadjuvant rectal (NAR) score is a promising indicator of survival after preoperative chemoradiotherapy for rectal cancer. However, its effectiveness after neoadjuvant chemotherapy (NAC) alone has not been fully investigated.

METHODS

We analyzed data retrospectively on 61 patients with rectal cancer, who received NAC followed by surgical resection between 2010 and 2015, and evaluated the impact of the NAR score on survival.

RESULTS

The median NAR score was 14.9. Of the 61 patients, 13, 35, and 13 were classified as having NAR-low (< 8), NAR-intermediate (8-16), and NAR-high (> 16) scores, respectively. The median observation period was 49.0 months. According to the NAR score, the 3-year DFS in the NAR-low group was 100%, which was significantly better than that in the NAR-intermediate (64.8%, p = 0.041), and NAR-high (61.5%, p = 0.018) groups. When the NAR-intermediate and NAR-high groups were investigated as a single high-risk group, the 3-year DFS of the patients who received adjuvant chemotherapy was 88.7%, which was significantly better than that of the patients who did not receive adjuvant chemotherapy (53.3%, p = 0.042).

CONCLUSIONS

The NAR score may predict the DFS and could serve as a favorable indicator of adjuvant chemotherapy after NAC alone.

Phase 2 study of perioperative chemotherapy with SOX and surgery for stage III colorectal cancer (SOS3 study)

This phase 2 study evaluated the safety and efficacy of perioperative chemotherapy with S-1 plus oxaliplatin (SOX) for stage III colorectal cancer (CRC). Patients with stage III CRC received surgery after neoadjuvant chemotherapy (NAC; SOX 4 cycles) and adjuvant chemotherapy (AC; SOX 4 cycles). The primary endpoints were response rate and safety. We enrolled 30 patients. Their median age was 62 years (range: 43-87 years); 53% were women. They received a median of 4 cycles (range: 1-4) of NAC and a median 4 cycles (range: 0-4) of AC. Five patients interrupted NAC treatment because of toxicity (grade 3 diarrhoea [n = 1], grade 3 ileus [n = 1], and grade 3-4 thrombocytopenia [n = 3]). Patients' responses were complete responses: n = 2 (6.6%), partial responses: n = 21 (70%), stable disease: n = 6 (20.0%), and progressive disease: n = 1 (3.3%; response rate: 73.3%). Curative resection was performed in 29 patients. No patients showed anastomotic leakage. Five-year overall survival and disease-free survival were 83.3% and 76.7%, respectively (median follow-up time: 48 months). NAC using SOX regimen is safe and effective, and may lead to reduced local recurrence and distant metastasis. Long-term outcomes are awaited to evaluate further the efficacy of this strategy (UMIN000006790).

Phase II study of capecitabine plus oxaliplatin (CapOX) as adjuvant chemotherapy for locally advanced rectal cancer (CORONA II)

Objective

This multicenter, single-arm phase II study (UMIN000008429) aimed to evaluate the efficacy and safety of capecitabine plus oxaliplatin (CapOX) as postoperative adjuvant chemotherapy for patients with locally advanced rectal cancer.

Methods

Patients with resectable clinical Stage II or III rectal cancer were enrolled to receive eight cycles of CapOX therapy (130 mg/m² oxaliplatin on day 1 and 2000 mg/m² oral capecitabine on days 1–14, every 3 weeks) after curative surgical resection. The primary endpoint was 3-year relapse-free survival (RFS) rate, and secondary endpoints were 3-year overall survival (OS) rate, treatment compliance, and safety.

Results

A total of 40 patients (Stage II, 21; Stage III, 19) were enrolled between September 2012 and November 2015 from seven institutions. Thirty-nine patients (97%) received R0 resection, and 32 patients (84%) received postoperative CapOX therapy. The completion rate of all eight cycles of CapOX therapy was 66%. Relative dose intensities were 87% for oxaliplatin and 84% for capecitabine. At a median follow-up period of 46 months, disease recurrence was observed in nine patients, including three with local recurrence. Three-year RFS and OS rates were 75% (95% CI 57–86%) and 96% (95% CI 80–99%), respectively. Frequencies of Grade ≥ 3 hematological and non-hematologic adverse events were 19% and 38%, respectively.

Conclusion

CapOX therapy is feasible as adjuvant chemotherapy for locally advanced rectal cancer.

Dual energy CT is useful for the prediction of mesenteric and lateral pelvic lymph node metastasis in rectal cancer

The aim of the present retrospective study was to investigate the predictability of dual-energy computed tomography (DECT) for pararectal lymph node (PRLN) metastasis and lateral pelvic lymph node (LPLN) metastasis in rectal cancer (RC). The present study involved 44 patients with RC who were examined by DECT and then underwent surgery between May 2015 and September 2017. LPLN dissection was performed in 24 patients. The normalized iodine concentration (nIC), the ratio of iodine concentration in the lymph node (LN) to that in the common iliac artery on DECT, of the largest PRLN and LPLN was calculated, and the association between LN metastasis and nIC was analyzed. The median nIC value for PRLNs was significantly lower in PRLN metastasis-positive cases compared with PRLN metastasis-negative cases in the arterial phase [0.18 vs. 0.25; P=0.01; cut-off, 0.24; area under the curve (AUC), 0.733] and portal phase (0.47 vs. 0.61; P=0.03; cut-off, 0.59; AUC, 0.701). A significant difference was not identified between the median maximum short axis diameter of PRLNs in PRLN metastasis-positive and metastasis-negative cases (7.6 vs. 6.4 mm; P=0.33). The nIC for LPLNs was not significantly different between LPLN metastasis-positive and metastasis-negative cases in the arterial phase (0.15 vs. 0.21; P=0.19); but was significantly lower in LPLN metastasis-positive cases compared with LPLN metastasis-negative cases in the portal phase (0.29 vs. 0.56; P=0.04; cut-off, 0.29; AUC, 0.877). The maximum short axis diameter of LPLNs was significantly larger in metastasis-positive cases compared with LPLN metastasis-negative cases (9.1 vs. 4.8 mm; P=0.03; cut-off, 7.0 mm; AUC, 0.912). In conclusion, the nIC was identified to be significantly lower in metastasis-positive cases, which may be useful for the prediction of PRLN and LPLN metastases. A combination of size-based diagnosis and DECT may increase the accuracy of preoperative diagnosis.

Comparable regional therapeutic effects between neoadjuvant chemotherapy and neoadjuvant chemoradiotherapy for locally advanced lower rectal cancer in terms of histopathological analysis

Neoadjuvant chemoradiotherapy (NACRT) for lower rectal cancer is commonly used in many Western countries. NACRT improves local control, but it may also induce anal dysfunction, postoperative complications, and late effects associated with radiation. Neoadjuvant chemotherapy (NAC) for lower rectal cancer has recently been employed to improve these problems, but the local control effect of NAC when compared with NACRT is controversial. The aim of the present study was to compare the effects of NAC and NACRT using histopathological analysis. The subjects included 16 patients treated with NAC and 10 patients treated with NACRT prior to surgery. Pathological effects on primary lesions and lymph nodes were evaluated based on fibrosis and tumor depth prior to and following preoperative therapy. In the NAC and NACRT groups, the T downgrade rates were 87.5 and 80%, T depth/F depth ratios were 0.61 and 0.73, pathological T downgrade rates were 25 and 40%, pathological complete response rates were 12.5 and 0% for primary lesions and 33.3 and 37.5% for lymph nodes, and the N conversion rates were 80 and 37.5%. There were no significant differences between the groups. These results suggest that the pathological therapeutic effects of NAC were similar to those of NACRT, and NAC may be effective as an alternative therapy to NACRT.

Feasibility of Neoadjuvant FOLFOX Therapy Without Radiotherapy for Baseline Resectable Rectal Cancer

BACKGROUND/AIM

The combination of oxaliplatin, leucovorin and fluorouracil (FOLFOX) has been established as postoperative adjuvant chemotherapy for stage III colon cancer. However, the safety and efficacy of neoadjuvant FOLFOX in patients with rectal cancer are still controversial. This prospective pilot study aimed to evaluate the feasibility of neoadjuvant FOLFOX therapy without radiation for baseline resectable rectal cancer (RC).

PATIENTS AND METHODS

The study included 30 patients with clinical stage II/III RC between February 2012 and December 2015. The patients were treated with six cycles of FOLFOX followed by elective surgery. The primary endpoint was the R0 resection rate. The secondary endpoints were the scheduled treatment completion rate, adverse events, pathological response and the disease-free survival (DFS) rate.

RESULTS

All the patients underwent elective R0 resection after neoadjuvant FOLFOX therapy. The completion rate of the 6-cycle regimen was 93.3% (28/30 patients). Grade 3-4 adverse events occurred in seven patients (23.3%). Pathological complete response was noted in two patients (6.7%). The 3-year DFS rate was 77.5% (95% confidence interval, 61.4%-93.7%).

CONCLUSION

Neoadjuvant FOLFOX therapy without radiation is a feasible therapeutic strategy for baseline resectable RC.

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

BACKGROUND

Chemoradiation (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/DESIGN

This 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.

FINDINGS

Twenty 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%).

INTERPRETATION

The 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.

Phase II trial of capecitabine plus oxaliplatin (CAPOX) as perioperative therapy for locally advanced rectal cancer

PURPOSE

The standard strategy for locally advanced lower rectal cancer is chemoradiotherapy followed by total mesorectal excision (TME) in Western countries and TME followed by adjuvant chemotherapy without preoperative treatment in Japan.

METHODS

This phase II trial evaluated the efficacy of a preoperative CAPOX chemotherapy regimen without radiation therapy for patients with locally advanced rectal cancer. The primary endpoint was 2-year disease-free survival.

RESULTS

The trial enrolled 45 patients from 9 institutions between 2012 and 2014. The mean age was 63.5 (29-74) years; 31 patients were male. Most patients (n = 41) received preoperative chemotherapy (CTx), and the preoperative CTx completion rate was 95.2%. R0 resection after CTx was performed in 41 patients. The pathological complete response rate was 7.3% (3/41). After surgery, 35 patients (85.3%) received adjuvant CTx, and 22 of 35 completed the protocol treatment. The follow-up period ranged from 0.71 to 4.68 years (median 2.86 years). There was recurrence in 13 of 40 patients who underwent R0 resection, and the 2-year disease-free survival rate and overall survival rate were 71.6 and 92.7%, respectively.

CONCLUSIONS

Here we report the completion rates for neoadjuvant CTx and adjuvant CTx, the pathological complete response rate, and the mid-term prognosis. The results indicate that CAPOX followed by TME may be a safe treatment strategy for locally advanced rectal cancer.

A review of preoperative chemoradiotherapy for lower rectal cancer

In Western countries, rectal cancer has been treated by chemoradiotherapy (CRT) for several decades now, and good local control has been reported. However, Japanese guidelines did not strongly recommend CRT, because CRT is only useful for achieving local control and imbues no survival benefit. For this reason, CRT was rarely used to treat rectal cancer in Japan. However, in the 2000s, several studies involving CRT began to be reported from Western countries, such as “correlation between pathological complete response and survival,” “induction chemotherapy followed by CRT,” and “watch-and-wait policies.” These studies were directly correlated with survival of and benefits to the patients. Given these findings, Japanese institutions have recently begun to introduce CRT for rectal cancer. Therefore, in the present study, we reviewed several topics regarding CRT for rectal cancer.

Impact of RAS/BRAF mutation status in locally advanced rectal cancer treated with preoperative chemotherapy

PURPOSE

Our sincere hope is to establish the predictive factors of neoadjuvant chemotherapy (NAC) response and provide patients with greater certainty regarding treatment outcomes. The aim of this study was to assess the response to NAC and survival in patients with locally advanced rectal cancer (LARC) according to their RAS/BRAF mutation status.

METHODS

Data on 57 patients with LARC who received NAC between 2009 and 2016 were analyzed retrospectively. The patients were classified into two groups based on their mutation status: wild-type in both RAS and BRAF (WT) or mutant-type in either RAS or BRAF (MT).

RESULTS

Twenty-three patients were classified as WT, and the remaining 34 patients were MT. Histological response to NAC was similar in both groups. In responders, the 3-year relapse-free survival (RFS) was better compared with the non-responders (92 and 66%, respectively). In the WT group, the 3-year RFS was 95% which was significantly better than that in the MT group (59%, p = 0.011). The MT group was further subdivided into the following 2 groups by the pathological response; the MT responders (n = 10) and MT non-responders (n = 24). The 3-year RFS was 50% in the MT non-responders, which was significantly worse compared to that in the remaining patients (92%, p = 0.001).

CONCLUSION

RAS/BRAF mutations did not affect the response to NAC. However, the RFS was likely to be poor for those in the MT group who did not achieve favorable pathological response. In contrast, the RFS was favorable in the WT group regardless of the pathological response.

Contemporary management of locally advanced rectal cancer: Resolving issues, controversies and shifting paradigms

Advancements in rectal cancer treatment have resulted in improvement only in locoregional control and have failed to address distant relapse, which is the predominant mode of treatment failure in rectal cancer. As the efficacy of conventional chemoradiotherapy (CRT) followed by total mesorectal excision (TME) reaches a plateau, the need for alternative strategies in locally advanced rectal cancer (LARC) has grown in relevance. Several novel strategies have been conceptualized to address this issue, including: 1) neoadjuvant induction and consolidation chemotherapy before CRT; 2) neoadjuvant chemotherapy alone to avoid the sequelae of radiation; and 3) nonoperative management for patients who achieved pathological or clinical complete response after CRT. This article explores the issues, recent advances and paradigm shifts in the management of LARC and emphasizes the need for a personalized treatment plan for each patient based on tumor stage, location, gene expression and quality of life.

The current status of treatment for colorectal cancer in China: A systematic review

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers all over the world, but its epidemiology is obviously different in various regions.

METHODS

The treatment of CRC also has varying characteristics due to differences in economy, geography, disease onset, chemotherapy, and other factors, although international guidelines are used to guide the treatment of CRC in China.

RESULTS

This paper summarizes the current status of CRC treatment, including surgical therapy, neoadjuvant radiotherapy and chemotherapy, postoperative chemotherapy, targeted therapy, maintenance therapy, and immunotherapy, according to the clinical situation in China, so as to provide better therapy and improve clinical practice for patients with CRC.

CONCLUSION

This research shows that the treatment of colorectal cancer continues to progress, and the patient's efficacy and quality of life have improved.

Inspection of Perirectal Lymph Nodes by One-Step Nucleic Acid Amplification Predicts Lateral Lymph Node Metastasis in Advanced Rectal Cancer

BACKGROUND

Lateral lymph node dissection (LLND) is performed for advanced rectal cancers in Japan; however, it can cause sexual and urinary dysfunction. The incidence of lateral LN metastasis is estimated at 7-13.9%; therefore, excessive rectal surgery with LLND should be avoided, especially for prophylactic purposes. To identify the patients who require LLND, we examined metastases in perirectal LNs by using a one-step nucleic acid amplification (OSNA) assay to predict lateral LN metastases.

METHODS

Twenty-five patients who underwent surgery with bilateral LN dissection due to T3-T4 rectal cancers were prospectively included in this study. Twenty-two patients (88.0%) received preoperative chemotherapy. Among 1052 LNs from 25 patients (median 40 per case), 135 perirectal LNs (median 6 per patient) were divided into three pieces and analyzed by OSNA, reverse transcriptase-polymerase chain reaction for carcinoembryonic antigen mRNA, and pathological examination after surgery. These results were compared with the pathological diagnosis of lateral LNs.

RESULTS

Lateral LN metastases were present in 4 of 25 patients (16.0%). All of these patients were positive by OSNA for perirectal LN metastases. The OSNA assay had a sensitivity of 100%, specificity of 86%, positive predictive value of 57%, and negative predictive value (NPV) of 100% for predicting lateral LN metastases.

CONCLUSIONS

The findings from this prospective study suggest that the OSNA assay of perirectal LNs may be useful for determining when LLND is necessary because of its high NPV, even in patients treated with preoperative chemotherapy.

Efficacy and safety of neoadjuvant chemotherapy with oxaliplatin, 5-fluorouracil, and levofolinate for T3 or T4 stage II/III rectal cancer: the FACT trial. Cancer Chemother Pharmacol. 2017;79:519-525. [PMID: 28150022 DOI: 10.1007/s00280-017-3243-7]

PURPOSE

A multicenter phase II clinical study was performed in patients with T3 or T4 stage II/III rectal cancer to evaluate the efficacy and safety of neoadjuvant chemotherapy with 5-fluorouracil, levofolinate, and oxaliplatin (mFOLFOX6).

METHODS

Patients received four 2-week cycles of mFOLFOX6 therapy (oxaliplatin at 85 mg/m² + leucovorin at 200 mg/m² + fluorouracil as a 400 mg/m² bolus followed by infusion of 2400 mg/m² over 46 h, all on Day 1). They were evaluated by computed tomography after completion of the fourth cycle. If there was no disease progression, two additional cycles were administered and then surgery was performed. Adjuvant chemotherapy was generally administered for 6 months using appropriate regimens at the discretion of the physician.

RESULTS

mFOLFOX6 therapy was given to 52 patients with locally advanced rectal cancer. The preoperative response rate was 48.8% and the operation rate was 80.8%. Serious adverse events of Grade 3-4 were neutropenia (n = 5), leukopenia (n = 1), thrombocytopenia (n = 1), febrile neutropenia (n = 1), nausea (n = 1), vomiting (n = 1), and peripheral neuropathy (n = 2). The R0 resection rate, pathologic complete response rate, and sphincter preservation rate were 91.0, 11.9, and 73.8%, respectively. Postoperative complications were tolerable.

CONCLUSIONS

The present results suggested that neoadjuvant therapy with mFOLFOX6 is safe and effective, representing a reasonable treatment option for locally advanced rectal cancer.