Neoadjuvant CAPOX and bevacizumab alone for locally advanced rectal cancer: long-term results from the N-SOG 03 trial

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 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.

Long-term results of a phase 2 study of neoadjuvant chemotherapy with molecularly targeted agents for locally advanced rectal cancer

BACKGROUND

We previously reported the feasibility and efficacy of neoadjuvant chemotherapy without radiotherapy for locally advanced rectal cancer. Here, we report the results of a long-term follow-up study.

METHODS

This was a multi-institutional, prospective phase 2 study of patients with locally advanced rectal cancer. Patients received neoadjuvant chemotherapy with molecularly targeted agents before undergoing total mesorectal excision. Six cycles of modified FOLFOX (mFOLFOX6) with bevacizumab were administered to KRAS-mutant patients, and mFOLFOX6 with cetuximab was administered to KRAS-wild-type patients. Here, we report the secondary end points of overall survival, relapse-free survival, and local recurrence rate.

RESULTS

Sixty patients were enrolled in this study. R0 resection was achieved in 98.3% (59/60) patients, and pathological complete response was achieved in 16.7% (10/60) patients. After a median follow-up of 5.4 years, the 5 year overall survival was 81.6%, the 5 year relapse-free survival was 71.7%, and the 5 year local recurrence rate was 12.6%. None of the patients who achieved pathological complete response developed recurrence within 5 years.

CONCLUSIONS

The use of molecularly targeted agents in the neoadjuvant setting for locally advanced rectal cancer has an acceptable prognosis.

Efficacy of neoadjuvant CapeOX/mFOLFOX6 without radiation for patients with baseline resectable mid-low locally advanced rectal cancer

OBJECTIVES

Chemotherapy without radiation therapy for locally advanced rectal cancer (LARC) has attracted increasing attention, but the optimal schema remains controversial. In this study, we aimed to assess the efficacy and toxicity of neoadjuvant chemotherapy (nCT) of two regimens for patients with mid-low baseline resectable LARC.

METHODS

A retrospective study was performed in 131 patients with baseline resectable LARC in a single center between April 2016 and August 2020. All patients received four cycles of neoadjuvant CapeOX or mFOLFOX6 before surgery. Clinical characteristics, pathological response, and survival status were then assessed.

RESULTS

After a 1:1 propensity score matching, 96 patients were enrolled, including 48 receiving CapeOX and 48 receiving mFOLFOX6. The objective regression rates were 50.00% and 58.33%, and the pathological complete response rates were 6.25% and 8.33%, respectively, in the CapeOX and mFOLFOX6 groups. Patients who received mFOLFOX6 had a better tumor regression grade (TRG) than those who received CapeOX (P = 0.005). Patients in both groups had similar survival outcomes.

CONCLUSIONS

The nCT has shown promising tumor response and survival outcomes, which can be a treatment option for baseline resectable LARC. For the two regimens, mFOLFOX6 provided better TRG than CapeOX, although no differences were observed in disease-free survival and OS.

Neoadjuvant chemotherapy for treatment patients with rectal cancer with adverse prognostic factors: A review

Rectal cancer (RC) is one of the leading tumor location in the structure of the incidence of malignant neoplasms in the Russian Federation and the world. And the standard approach to the treatment of patients with locally advanced forms of RC is preoperative chemo-radiotherapy (CRT) with delayed surgery. The use of such sort of approach in the recent decades has led to the reduction of the frequency of local recurrence up to 10% and even less. However, approximately a third of patients die of distant metastases. In this regard, one of the main tasks in the treatment of patients with locally advanced forms of RC with adverse prognostic factors is the prevention of distant metastasis formation. Early initiation of the systemic therapy before surgery is aimed at solving this issue. Conducting neoadjuvant chemotherapy (NCT) instead of CRT in RC treatment allows to avoid radiation reactions and injuries, occurring in some patients. Two-component oxaliplatin-containing regimens are the most well studied types of NCT in the treatment of patients with non-metastatic RC. In this connection, despite the differences in the treatment regimens and the number of cycles, a good tolerability of the method as well as no effect on the frequency of postoperative complications and in general a satisfactory results comparable to the effects of CRT were observed. The use of NCT in combination with targeted treatment modalities as well as three-component chemotherapy regimens are promising and encouraging treatment options for patients with RC with adverse prognostic factors.

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.

Biologics in rectal cancer

INTRODUCTION

Despite the use of multimodality therapy, locally advanced rectal cancer (LARC) still presents high rates of disease recurrence. Fluoropyrimidine-based chemotherapy concurrently with radiation therapy (RT) remains the cornerstone of neoadjuvant therapy of LARC, and novel therapies are urgently needed in order to improve the clinical outcomes.

AREAS COVERED

We aim to summarize data from completed and ongoing clinical trials addressing the role of biological therapies, including monoclonal antibodies, immune checkpoint inhibitors (ICIs), antibody-drug conjugates, bispecific antibodies, and gene therapies in the systemic therapy of rectal cancer.

EXPERT OPINION

Deeper understanding of the molecular biology of colorectal cancer (CRC) has allowed meaningful advances in the systemic therapy of metastatic disease in the past few years. The larger applicability of biological therapy in CRC, including genome-guided targeted therapy, antiangiogenics, and immunotherapy, gives us optimism for the personalized management of rectal cancer. Microsatellite instability (MSI) tumors have demonstrated high sensitivity to ICIs, and preliminary findings in the neoadjuvant setting of rectal cancer are promising. To date, antiangiogenic and anti-EGFR therapies in LARC have not demonstrated the same benefit seen in metastatic disease. The outstanding results accomplished by biomarker-guided therapy in metastatic CRC will guide future developments of biological therapy in LARC.

The survival impact of preoperative FOLFOX for resectable locally advanced rectal cancer: the R-NAC-01 study

PURPOSE

In this follow-up of the R-NAC-01 study, we assessed the long-term oncological benefit of four courses of modified leucovorin, 5-fluorouracil (FU), and oxaliplatin (mFOLFOX6) chemotherapy before rectal surgery.

METHODS

In this prospective, multicenter study (UMIN 000012559) involving 11 hospitals in Japan, patients with lower rectal cancer underwent four cycles of mFOLFOX6 chemotherapy and subsequent surgery within four to six weeks. The 3-year recurrence-free survival and local recurrence rates were then reported.

RESULTS

Of 41 patients (36 males, 5 females; mean age: 60.8 years old) who received 4 courses of chemotherapy, 40 underwent total mesorectal excision, and 1 underwent total pelvic exenteration. R0 resection was achieved in 40 patients, but none showed a pathological complete response. Twenty-nine patients received adjuvant chemotherapy for an average of 4 months. The 3 year recurrence-free survival and local recurrence rates in patients undergoing curable resection were 72.8% and 8.5%, respectively. cStage III patients with adjuvant chemotherapy had a significantly higher 3 year recurrence-free survival than those without adjuvant chemotherapy (76.6 vs. 40.0%, log-rank p = 0.03).

CONCLUSION

Four courses of mFOLFOX6 chemotherapy before surgery may be a promising treatment strategy for locally advanced rectal cancer. Adjuvant chemotherapy might be needed for cStage III patients, even after four courses of neoadjuvant mFOLFOX6.

Current State of Neoadjuvant Radiotherapy for Rectal Cancer

Colorectal cancer is the third most commonly diagnosed cancer, with rectal cancer accounting for 30% of cases. The current standard of care curative treatment for locally advanced rectal cancer is (chemo)radiotherapy followed by surgery and adjuvant chemotherapy. Although neoadjuvant radiotherapy has reduced the risk of local recurrence to less than 10%, the risk of distant metastasis remained high at 30% affecting patient survival. In addition, there is a recognition that there is heterogeneity in tumor biology and treatment response with good responders potentially suitable for treatment de-escalation. Therefore, new treatment sequencing and regimens were investigated. Here, we reviewed the evidence for current neoadjuvant treatment options in patients with locally advanced rectal adenocarcinoma, and highlight the new challenges in this new treatment landscape.

Neoadjuvant chemotherapy without radiotherapy for patients with locally advanced rectal cancer. Oncologic outcomes

BACKGROUND

the standard treatment for locally advanced rectal cancer is neoadjuvant chemo-radiotherapy, surgery and adjuvant chemotherapy. Only 50% of patients receive the adjuvant treatment due to the surgical complications and toxicity of radiotherapy. Recently, neoadjuvant chemotherapy has been investigated in the locally advanced rectal cancer setting, with the aim of guaranteeing an uninterrupted systemic treatment. The objective of the present study was to assess the safety and efficacy of neoadjuvant chemotherapy in locally advanced rectal cancer.

METHODS AND PATIENTS

patients treated with neoadjuvant chemotherapy and surgery were identified from a prospective database of patients with rectal cancer (cII-III). The primary outcomes were the assessment of the number of R0 resections, the degree of pathologic response, patterns of recurrence and overall and disease-free survival. Treatment schedule: patients received 6-8 cycles of oxaliplatin and fluoropyrimides based chemotherapy.

RESULTS

twenty-seven patients who received neoadjuvant chemotherapy were identified. Twenty-six anterior resections and one Hartmann intervention were performed. An R0 resection was performed in 27 (100%) patients and no involvement of the circumferential margin was observed. Complete pathologic response (ypT0N0) was confirmed in four (14.8%) patients. The median follow-up was 35 months (range: 10-81) and four distant recurrences were recorded. Overall and disease-free survival at five years was 85% and 84.7%, respectively. Twenty-seven (100%) patients received all the cycles of chemotherapy, with a mean of six cycles (range 5-8) per patient.

CONCLUSIONS

neoadjuvant chemotherapy is a promising alternative in the locally advanced rectal cancer setting and further phase III clinical trials are clearly warranted.

The efficacy and safety of adding bevacizumab in neoadjuvant therapy for locally advanced rectal cancer patients: A systematic review and meta-analysis

Background

Patients with locally advanced rectal cancer (LARC) are more likely to suffer local recurrence and distant metastases, contributing to worse prognoses. Considering the provided dramatic reduction of local recurrences, neoadjuvant CRT (nCRT) followed by curative resection with total mesorectal excision (TME) and adjuvant chemotherapy has been established as standard therapy for LARC patients. However, the efficacy of adding bevacizumab in neoadjuvant therapy, especially in induction therapy-containing nCRT for LARC patients remains uncertain.

Materials

PubMed, Embase, and Web of Science were searched to retrieve records on the application of bevacizumab in a neoadjuvant setting for LARC patients. The endpoints of interest were pCR and the rates of patients suffering Grade 3/4 bevacizumab-specific adverse events, namely bleeding, wound healing complications, and gastrointestinal perforation.

Results

29 cohorts covering 1134 subjects were included in this systematic review. The pooled pCR rate for bevacizumab-relevant cohorts was 21% (95% confidence interval (95% CI), 17–25%; I² = 61.8%), the pooled estimates of Grade 3/4 bleeding, Grade 3/4 wound healing complication, Grade 3/4 gastrointestinal perforation were 1% (95% CI, 0–3%; I² = 0%), 2% (95% CI, 1–5%; I² = 4.7%), and 2% (95% CI, 0–5%; I² = 0%), respectively.

Conclusion

The addition of bevacizumab in the nCRT, especially in the TNT, for LARC patients provides promising efficacy and acceptable safety. However, the results should be interpreted cautiously due to the small amount of relevant data and need further confirmation by future studies.

Indications for neoadjuvant treatment based on risk factors for poor prognosis before and after neoadjuvant chemotherapy alone in patients with locally advanced rectal cancer

INTRODUCTION

The oncological benefit of neoadjuvant chemotherapy (NAC) alone for locally advanced rectal cancer (LARC) remains controversial. The aim of this study was to clarify the clinical risk factors for poor prognosis before and after NAC for decision making regarding additional treatment in patients with LARC.

MATERIALS AND METHODS

We examined a total of 96 patients with MRI-defined poor-risk locally advanced mid-low rectal cancer treated by NAC alone between 2006 and 2018. Survival outcomes and clinical risk factors for poor prognosis before and after NAC were analyzed.

RESULTS

In the median follow-up duration after surgery of 60 months (3-120), the rates of 5-year overall survival (OS), relapse-free survival (RFS), and local recurrence (LR) were 83.6%, 78.4%, and 8.2%, respectively. In the multivariate analyses, patients with cT4 disease had a significantly higher risk of poor OS (HR; 6.10, 95% CI; 1.32-28.15, P = 0.021) than those with cT3 disease. After NAC, ycN+ was significantly associated with a higher risk of poor OS (HR; 5.92, 95% CI; 1.27-27.62, P = 0.024) and RFS (HR; 2.55, 95% CI; 1.01-6.48, P = 0.048) than ycN-. In addition, patients with CEA after NAC (post-CEA) ≥ 5 ng/ml had a significantly higher risk LR (HR; 5.63, 95% CI; 1.06-29.93, P = 0.043).

CONCLUSION

NAC alone had an insufficient survival effect on patients with cT4 disease, ycN+, or an elevated post-CEA level. In contrast, NAC alone is a potential treatment for other patients with LARC.

What is the impact of systemic chemotherapy for lateral lymph nodes in patients with locally advanced low rectal cancer?

PURPOSE

Systemic chemotherapy (SC) before surgery is a potential treatment to improve survival in patients with advanced rectal cancer. However, the impact of SC on lateral lymph nodes (LLNs) remains unclear.

METHODS

A total of 78 patients with stage II/III low rectal cancer, who received 3-month oxaliplatin-based SC followed by LLN dissection (LLND) in principle, were analysed retrospectively. "Total lateral lymph node metastases (tLLNMs)" was defined as having either pathological LLNMs (pLLNMs) or lateral local recurrences (LLRs). Patients with the maximum short-axis size of LLNs ≥ 7 mm were classified into the swollen group (n = 21).

RESULTS

In the total cohort, tLLNMs included 6 pLLNMs (7.7%) and 2 LLRs (2.6%). In the non-swollen group, no patients had pLLNMs, but one had LLR (1.8%). In the swollen group, pLLNMs and LLRs were detected in 6 (28.6%) and 1 (4.8%), respectively. The swollen group was an independent risk factor for tLLNMs (P < 0.001), leading to the significantly worse 5-year relapse-free survival (RFS) of 52.4% than the others.

CONCLUSION

For patients without swollen LLNs, SC could allow for omission both of lateral irradiation and LLND. For patients with swollen LLNs, the lateral local control was favourable after SC and LLND without chemoradiotherapy (CRT); however, oxaliplatin-based SC might be insufficient to improve survival, requiring more intensive chemotherapy. CRT should be indicated according to the other risk factors of central local recurrence, although the swollen LLNs should be removed.

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.