Disappearing Colorectal Liver Metastases: Do We Really Need a Ghostbuster?

The development of new systemic treatment strategies has resulted in a significant increase in the response rates of colorectal liver metastases (CRLM) in the last few years. Although the radiological response is a favorable prognostic factor, complete shrinkage of CRLM, known as disappearing liver metastases (DLM), presents a therapeutic dilemma, and proper management is still debated in the literature. In fact, DLM is not necessarily equal to cure, and when resected, pathological examination reveals in more than 80% of patients a variable percentage of the tumor as residual disease or early recurrence in situ. Moreover, while a higher incidence of intrahepatic recurrence is documented in small series when surgery is avoided, its clinical significance for long-term OS is still under investigation. In light of this, a multidisciplinary approach and, in particular, radiologists’ role is needed to assist the surgeon in the management of DLM, thanks to emerging technology and strategy. Therefore, the aim of this review is to provide an overview of the DLM phenomenon and current management.

Efficacy and Safety of Systemic Treatments Among Colorectal Cancer Patients: A Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Systemic treatments, namely, either monotherapy or combination therapy, are commonly administered to patients with advanced or metastatic colorectal cancer (CRC). This study aimed to provide the complete efficacy and safety profiles and ranking of systemic therapies for the treatment of unresectable advanced or metastatic CRC.

METHODS

We searched PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov from inception until June 30, 2021, and also the bibliographies of relevant studies. Randomized controlled trials comparing two or more treatments, namely, at least capecitabine, 5-fluorouracil, leucovorin, irinotecan, bevacizumab, cetuximab, oxaliplatin, or panitumumab were investigated. A network meta-analysis using the Bayesian approach was performed to compare the efficacy and safety of treatments. The surface under the cumulative ranking curve (SUCRA) was calculated for the probability of each treatment as the most effective. The overall response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), adverse events (AEs) grade ≥3, and serious adverse events (SAEs) were evaluated.

RESULTS

One hundred two publications with 36,147 participants were assigned to 39 different treatments. Among 11 treatments with full information on six outcomes, FOLFIRI/FOLFOX/FOLFOXIRI + bevacizumab significantly improved both the ORR and DCR, compared to FOLFIRI. Although FOLFOX and FOLFIRI/FOLFOX + cetuximab significantly prolonged both OS and PFS, treatments were comparable in terms of AEs grade ≥3 and SAEs. The top highest SUCRA values were observed in the FOLFOXIRI + panitumumab group for ORR (96%) and DCR (99%), FOLFIRI + bevacizumab + panitumumab group for OS (62%) and PFS (54%), and FOLFOXIRI + bevacizumab group for AEs grade ≥3 (59%) and SAEs (59%) outcomes.

CONCLUSIONS

These findings suggest an available range of systemic treatment therapies with different efficacy and safety profiles with patients. Further investigations of the side effects and mutation status are required to confirm our findings.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42019127772.

Treatment sequencing of metastatic colorectal cancer based on primary tumor location

Colorectal cancer is a heterogeneous disease with various clinical, molecular, and embryological differences related to the origin of the tumor from the right or left colon. Recent studies have demonstrated that tumor sidedness has both a prognostic and predictive value in metastatic colorectal cancer . Patients whose primary tumor originates from the left side of the colon and whose tumor's genome encodes wild-type RAS and BRAF should be offered cetuximab or panitumumab in the first-line treatment of metastatic disease or in subsequent lines. For tumors originating from the right side of the colon, anti-angiogenic treatment, particularly bevacizumab, is an option for this poor prognostic group until better options become available. Specifically, an aggressive initial approach with FOLFOXIRI plus bevacizumab is a treatment option in right-sided tumors under investigation. This report reviews the available data for the treatment of metastatic colorectal cancer according to the location of the primary tumor and proposes the optimal treatment sequencing strategy incorporating the site of origin of the tumor and molecular information into the decision-making process.

Colon Cancer, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon Cancer focuses on systemic therapy options for the treatment of metastatic colorectal cancer (mCRC), because important updates have recently been made to this section. These updates include recommendations for first-line use of checkpoint inhibitors for mCRC, that is deficient mismatch repair/microsatellite instability-high, recommendations related to the use of biosimilars, and expanded recommendations for biomarker testing. The systemic therapy recommendations now include targeted therapy options for patients with mCRC that is HER2-amplified, or BRAF V600E mutation-positive. Treatment and management of nonmetastatic or resectable/ablatable metastatic disease are discussed in the complete version of the NCCN Guidelines for Colon Cancer available at NCCN.org. Additional topics covered in the complete version include risk assessment, staging, pathology, posttreatment surveillance, and survivorship.

Combining Correlated Outcomes and Surrogate Endpoints in a Network Meta-Analysis of Colorectal Cancer Treatments

This study aimed to investigate the efficacy and safety of systemic therapies in the treatment of unresectable advanced or metastatic colorectal cancer. Predicted hazard ratios (HRs) and their 95% credible intervals (CrIs) for overall survival (OS) were calculated from the odds ratio (OR) for the overall response rate and/or HR for progression-free survival using multivariate random effects (MVRE) models. We performed a network meta-analysis (NMA) of 49 articles to compare the efficacy and safety of FOLFOX/FOLFIRI±bevacizumab (Bmab)/cetuximab (Cmab)/panitumumab (Pmab), and FOLFOXIRI/CAPEOX±Bmab. The NMA showed significant OS improvement with FOLFOX, FOLFOX+Cmab, and FOLFIRI+Cmab compared with that of FOLFIRI (HR = 0.84, 95% CrI = 0.73-0.98; HR = 0.76, 95% CrI = 0.62-0.94; HR = 0.80, 95% CrI = 0.66-0.96, respectively), as well as with FOLFOX+Cmab and FOLFIRI+Cmab compared with that of FOLFOXIRI (HR = 0.69, 95% CrI = 0.51-0.94 and HR = 0.73, 95% CrI = 0.54-0.97, respectively). The odds of adverse events grade ≥3 were significantly higher for FOLFOX+Cmab vs. FOLFIRI+Bmab (OR = 2.34, 95% CrI = 1.01-4.66). Higher odds of events were observed for FOLFIRI+Pmab in comparison with FOLFIRI (OR = 2.16, 95% CrI = 1.09-3.84) and FOLFIRI+Bmab (OR = 3.14, 95% CrI = 1.51-5.89). FOLFOX+Cmab and FOLFIRI+Bmab showed high probabilities of being first- and second-line treatments in terms of the efficacy and safety, respectively. The findings of the efficacy and safety comparisons may support the selection of appropriate treatments in clinical practice. PROSPERO registration: CRD42020153640.

Phase II study on first-line treatment of NIVolumab in combination with folfoxiri/bevacizumab in patients with Advanced COloRectal cancer RAS or BRAF mutated - NIVACOR trial (GOIRC-03-2018)

Background

FOLFOXIRI (fluorouracil, leucovorin, oxaliplatin, and irinotecan) plus bevacizumab has shown to be one of the therapeutic regimens in first line with the highest activity in patients (pts.) with metastatic colorectal cancer (mCRC) unselected for biomolecular alterations. Generally, tumors co-opt the programmed death-1/ligand 1 (PD-1/PD-L1) signaling pathway as one key mechanism to evade immune surveillance. As today, anti-PD-1 monoclonal antibodies are FDA approved only for DNA mismatch repair deficient/microsatellite instability-high (MMRd/MSI-H), which represent only about 5% among all mCRC. Nowadays, there are no data demonstrating anti PD-1 activity in proficient and stable disease (MMRp/MSS). A different target in mCRC is also the Vascular Endothelial Growth Factor A (VEGF-A), which acts on endothelial cells to stimulate angiogenesis. VEGF-A inhibition with bevacizumab has shown to increase the immune cell infiltration, providing a solid rationale for combining VEGF targeted agents with immune checkpoint inhibitors. Based on these evidences, we explore the combination of triplet chemotherapy (FOLFOXIRI) with bevacizumab and nivolumab in pts. with mCRC RAS/BRAF mutant regardless of microsatellite status.

Methods/design

This is a prospective, open-label, multicentric phase II trial where pts. with mCRC RAS/BRAF mutated, in first line will receive nivolumab in combination with FOLFOXIRI/bevacizumab every 2 weeks for 8 cycles followed by maintenance with bevacizumab plus nivolumab every 2 weeks. Bevacizumab will be administered intravenously at dose of 5 mg/kg every 2 weeks and nivolumab intravenously as a flat dose of 240 mg every 2 weeks. The primary endpoint is the overall response rate (ORR). This study hypothesis is that the treatment is able to improve the ORR from 66 to 80%. Secondary endpoints include OS, safety, time to progression, duration of response. Collateral translational studies evaluate the i) tumor mutational burden, and ii) genetic alterations by circulating free DNA (cfDNA) obtained from plasma samples. The trial is open to enrollment, 9 of planned 70 pts. have been enrolled.

Trial registration

NIVACOR is registered at ClinicalTrials.gov: NCT04072198, August 28, 2019.

Survival benefit of surgical resection after first-line triplet chemotherapy and bevacizumab in patients with initially unresectable metastatic colorectal cancer

BACKGROUND

Surgical resection of metastatic disease in patients with initially non-resectable colorectal cancer (CRC) has improved overall survival. Intensified chemotherapy regimens have increased the probability of converting unresectable metastasis to resectable. Here, we report the result of combining intensive chemotherapy (triplet) and surgical resection of metastatic lesions in patients with metastatic CRC.

PATIENTS AND METHODS

Patients with unresectable metastatic CRC were enrolled in phase I/II trial of triplet chemotherapy consisting of capecitabine, oxaliplatin, irinotecan, and bevacizumab. Patients were given 5-8 cycles induction chemotherapy of the above regimen followed by maintenance capecitabine and bevacizumab until disease progression, unacceptable toxicity, or patient request. All patients were assessed at a multidisciplinary conference for possible surgical resection of their metastatic disease at the time of inclusion in the trial and 2 monthly intervals thereafter. Patients who underwent R0 resection of their metastatic disease received adjuvant oxaliplatin and capecitabine to complete a total of 6 months of chemotherapy.

RESULTS

Fifty-three patients were enrolled. The median age was 52 years (range 23-74), 29 (55%) were males, ECOG PS 0-1 was 13 (66%), 11 (42%) had a right-sided tumor, 29 (55%) had resection of their primary tumor, 22 (42%) had a single metastatic site, and 8 (15.1%) had a liver-limited disease. Thirteen patients (24.5%) underwent surgical resection of residual metastatic disease +/- the primary tumor with 10 (18.9%) of them were R0. The surgical group had a higher incidence of males compared to the non-surgical group (69.3% vs 47.2%, p = 0.2), equal performance status, lower median number of metastatic sites (1 vs 2, p = 0.09), higher mutant Kras (53.8% vs 34.2%, p = 0.3), and higher response rate (84.6% vs 56.2%, p = 0.3). With a median follow-up duration of 89 months, the median PFS for the whole group was 16.1 months [95% confidence interval (CI) 9.1-20] and the median OS was 28.2 months (95% CI 22.5-53.3). The median PFS for the surgery group was 18.9 months (95% CI 12.6-not reached) compared to 9.6 months (95% CI 7.0-18.3) for the non-surgical group, log-rank p = 0.0165. The median OS for both groups was not reached (95% CI 53.3-not reached) and 23.2 months (95% CI 17.0-28.4) respectively, log-rank p = 0.0006. Five-year PFS and OS for the surgery group were 46.2% and 67.6% respectively.

CONCLUSIONS

Patients with unresectable metastatic CRC and fit for triplet chemotherapy should have the benefit of combining this intensified regimen and surgical resection of their metastatic disease if possible.

TRIAL REGISTRATION

Clinicaltrials.gov , NCT01311050 , registered March 6, 2011, retrospectively registered.

Considering FOLFOXIRI plus bevacizumab for metastatic colorectal cancer with left-sided tumors

A recent subgroup analysis of the TRIBE trial suggested that FOLFOXIRI plus bevacizumab may be a preferred option for the first-line treatment of only right-sided metastatic colorectal cancer (mCRC), regardless of RAS or BRAF status. Our subanalysis of a phase II trial of the FOLFOXIRI triplet regimen plus bevacizumab in patients with mCRC who had RAS mutant tumors showed that tumor shrinkage was better and the duration of treatment was longer in patients with left-sided tumors than in those with right-sided tumors, leading to a higher rate of conversion to surgery in mCRC patients with left-sided tumors. The early and deep responses to the triplet-regimen in patients with left-sided tumors might facilitate conversion treatment resulting in favorable survival. Our data suggest that the FOLFOXIRI plus bevacizumab might be a promising treatment for left-sided mCRC involving RAS mutant tumors.

First-line molecular therapies in the treatment of metastatic colorectal cancer - a literature-based review of phases II and III trials

Introduction:

Metastatic colorectal cancer (mCRC) is one of the most common cancers and the second leading cause of cancer worldwide. With the improvement of systemic and operative therapies, median overall survival (mOS) reached 30 months or longer. Here, we will review the use of the anti-vascular endothelial growth factor (VEGF) and anti-epidermal growth factor receptor (EGFR) antibodies in combination with doublet and triplet chemotherapy in patients with borderline and primary unresectable mCRC.

Methods:

Phases II and III trials were included in investigating chemotherapy in the first-line in combination with an anti-VEGF(R) or anti-EGFR in a cohort of patients with mCRC.

Results:

The VEGF-antibody bevacizumab has improved progression-free survival (PFS) in several phase III trials in combination with a chemotherapy doublet. More recently, a higher efficacy has been demonstrated in combination with an intensified chemotherapy including 5-fluoropyrimidine (5-FU), oxaliplatin, and irinotecan within the phase III TRIBE study. Similarly, high resectability rates have been shown in the phase II Olivia trial for patients with liver-limited disease with an intensified chemotherapeutic regime. However, this increase in efficacy was accompanied by an increase in toxicity as well. The efficacy of the EGFR-antibodies cetuximab and panitumumab has been shown in several phase III trials, but their use is restricted to patients whose tumors are RAS wildtype (WT). The phase II trials, CELIM and PLANET, demonstrated a favorable long-term survival for patients with initially non-resectable colorectal liver metastases who respond to conversion therapy with EGFR-antibodies and undergo secondary resection. The CLGB and FIRE-3 trials delivered an inconsistent finding whether anti-VEGF or -EGFR treatment is the better option in the first-line setting. However, there is increasing evidence from post hoc analyses of prospective clinical trials that patients with left-sided tumors benefit from EGFR-directed combination therapy in terms of prolongation of OS and PFS compared with limited, if any, benefit for those with right-sided tumors.

Conclusion:

Both anti-VEGF- and anti-EGFR-directed therapies represent efficient treatment options for patients with mCRC in the first line. For patients with RAS WT, left-sided tumor anti-EGFR-based treatment is recommended. Intensified regimens can be offered initially to unresectable patients in order to achieve resectability at a price of higher toxicity.

A phase II trial of 1st-line modified-FOLFOXIRI plus bevacizumab treatment for metastatic colorectal cancer harboring RAS mutation: JACCRO CC-11

FOLFOXIRI plus bevacizumab is considered a standard initial therapy for metastatic colorectal cancer (mCRC). However, few prospective trials have evaluated triplet therapy plus bevacizumab in patients with RAS mutant mCRC. Patients with an age of 20 to 75 years, and unresectable, measurable tumors harboring RAS mutation were given first-line treatment with bevacizumab (5 mg/kg on day 1) plus modified-FOLFOXIRI (irinotecan 150 mg/m², oxaliplatin 85 mg/m², levofolinate 200 mg/m², and fluorouracil 2400 mg/m² as a 46-h continuous infusion on day 1, repeated every 2 weeks). The primary endpoint was the objective response rate (ORR) as evaluated by an external review board. Progression-free survival (PFS), overall survival, early tumor shrinkage (ETS), depth of response (DpR), and safety were secondary endpoints. Among 64 patients who were enrolled between October 2014 and August 2016, 62 were evaluable for efficacy (right-sided tumors in 27%). ORR and disease control rate were 75.8% (95% confidence interval [CI] 65.1-86.5) and 96.8%, respectively. ETS was 73.8%, and median DpR was 49.2%. Median PFS was 11.5 (95% CI 9.5-14.0) months as of the cut-off date of September 2017. Adverse events of grade 3 or 4 were neutropenia (54%), hypertension (32%), diarrhea (13%), anorexia (11%), peripheral neuropathy (2%), and febrile neutropenia (5%). In conclusion, this prospective trial demonstrated for the first time that FOLFOXIRI plus bevacizumab is an active first-line treatment for patients with RAS mutant mCRC. Modified-FOLFOXIRI plus bevacizumab might become an alternative regimen of triplet chemotherapy for mCRC in Japan.