The prognostic value of radiomic features in liver-limited metastatic colorectal cancer patients from the TRIBE2 study.

Aims: Evaluating the prognostic role of radiomic features in liver-limited metastatic colorectal cancer treated with first-line therapy at baseline and best response among patients undergoing resection. Patients & methods: Among patients enrolled in TRIBE2 (NCT02339116), the association of clinical and radiomic data, extracted by SOPHiA-DDM™ with progression-free and overall survival (OS) in the overall population and with disease-free survival/postresection OS in those undergoing resection was investigated. Results: Among 98 patients, radiomic parameters improved the prediction accuracy of our model for OS (area under the curve: 0.83; sensitivity: 0.85; specificity: 0.73; accuracy: 0.78), but not progression-free survival. Of 46 resected patients, small-distance high gray-level emphasis was associated with shorter disease-free survival and high gray-level zone emphasis/higher kurtosis with shorter postresection OS. Conclusion: Radiomic features should be implemented as tools of outcome prediction for liver-limited metastatic colorectal cancer.

Benefit from upfront FOLFOXIRI and bevacizumab in BRAFV600E-mutated metastatic colorectal cancer patients: does primary tumour location matter?

BACKGROUND: Recent data suggest that BRAFV600E-mutated metastatic colorectal cancer (mCRC) patients with right-sided tumours and ECOG-PS = 0 may achieve benefit from the triplet regimen differently than those with left-sided tumours and ECOG-PS > 0. METHODS: The predictive impact of primary sidedness and ECOG-PS was evaluated in a large real-life dataset of 296 BRAFV600E-mutated mCRC patients treated with upfront triplet or doublet ± bevacizumab. Biological differences between right- and left-sided BRAFV600E-mutated CRCs were further investigated in an independent cohort of 1162 samples. RESULTS: A significant interaction effect between primary sidedness and treatment intensity was reported in terms of both PFS (p = 0.010) and OS (p = 0.003), with a beneficial effect of the triplet in the right-sided group and a possible detrimental effect in the left-sided. No interaction effect was observed between ECOG-PS and chemo-backbone. In the MSS/pMMR population, a consistent trend for a side-related subgroup effect was observed when FOLFOXIRI ± bevacizumab was compared to oxaliplatin-based doublets±bevacizumab (p = 0.097 and 0.16 for PFS and OS, respectively). Among MSS/pMMR tumours, the BM1 subtype was more prevalent in the right-sided group (p = 0.0019, q = 0.0139). No significant differences were observed according to sidedness in the MSI-H/dMMR population. CONCLUSIONS: Real-life data support the use of FOLFOXIRI ± bevacizumab only in BRAFV600E-mutated mCRC patients with right-sided tumours.

Primary tumour side as a driver for treatment choice in RAS wild-type metastatic colorectal cancer patients: a systematic review and pooled analysis of randomised trials.

BACKGROUND: Retrospective subgroup analyses of previous trials in the first-line therapy of RAS wt metastatic colorectal cancer (mCRC) suggested a predictive impact of primary tumour side on the efficacy of anti-epidermal growth factor receptor (EGFR) agents. Recently, new head-to-head trials of doublets/bevacizumab versus doublets/anti-EGFR, PARADIGM and CAIRO5 were presented. PATIENTS AND METHODS: We searched for phase II and III trials comparing doublet chemotherapy plus an anti-EGFR or bevacizumab as the first-line treatment for RAS wt mCRC patients. Overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and radical resection rate result in the overall study populations and, according to the primary side, were pooled together in a two-stage analysis with random effects and fixed effect models. The interaction between sidedness and treatment effect was then analysed. RESULTS: We identified five trials (PEAK, CALGB/SWOG 80405, FIRE-3, PARADIGM and CAIRO5), including 2739 patients, 77% left- and 23% right-sided. Among patients with left-sided mCRC, the use of anti-EGFRs was associated with higher ORR (74% versus 62%, OR = 1.77 [95% confidence interval {CI} 1.39-2.26-0.88], p < 0.0001), longer OS (hazard ratio [HR] = 0.77 [95% CI 0.68-0.88], p < 0.0001) and not significantly longer PFS (HR = 0.92, p = 0.19). Among patients with right-sided mCRC, the use of bevacizumab was associated with longer PFS (HR = 1.36 [95% CI 1.12-1.65], p = 0.002) and not significantly longer OS (HR = 1.17, p = 0.14). A subgroup analysis confirmed a significant interaction effect between the primary tumour side and treatment arm in terms of ORR (p = 0.02), PFS (p = 0.0004) and OS (p = 0.001). No differences in the radical resection rate were found according to treatment and sidedness. CONCLUSIONS: Our updated metanalysis corroborates the role of the primary tumour location in the choice of the upfront therapy for RAS wt mCRC patients, leading to strongly recommend anti-EGFRs in left-sided tumours and to prefer bevacizumab in the right-sided.

Total neoadjuvant treatment and organ preservation strategies in the management of localized rectal cancer: A narrative review and evidence-based algorithm.

The multimodal approach with total mesorectal excision preceded by neoadjuvant (chemo)radiotherapy represented the mainstay treatment for locally advanced rectal cancer (LARC) for a long time. However, the benefit of adjuvant chemotherapy in terms of distant relapse reduction is limited. Recently, chemotherapy regimens administered before surgery and incorporated with (chemo)radiotherapy in total neoadjuvant treatment protocols have been established as new options in the management of LARC. Meanwhile, patients with clinical complete response to neoadjuvant treatment can benefit from organ preservation strategies, aimed at sparing surgery and long-term post-operative morbidities, while preserving an adequate disease control. However, the introduction of a non-operative management in clinical practice is a matter of debate with some concerns regarding the risk of local recurrence and long-term outcomes. In this review, we discuss how these recent advances are reshaping the multimodal management of localized rectal cancer and propose an algorithm to place them in the clinical practice.

ShorTrip Trial: A Prospective, Multicentric Phase II Single-Arm Trial of Short-Course Radiotherapy Followed by Intensified Consolidation Chemotherapy With the Triplet FOLFOXIRI as Total Neoadjuvant Therapy in Locally Advanced Rectal Cancer.

BACKGROUND: In patients with locally advanced rectal cancer (LARC) treated with preoperative (chemo) radiotherapy and surgery, adjuvant chemotherapy is poorly feasible and its benefit is questionable. In the last years, several total neoadjuvant treatment (TNT) strategies, moving the adjuvant chemotherapy to the neoadjuvant setting, have been investigated with the aim of improving compliance to systemic chemotherapy, treating micrometastases earlier and then reducing distant recurrence. PATIENTS AND METHODS: ShorTrip (NTC05253846) is a prospective, multicentre, single-arm phase II trial where 63 patients with LARC will be treated with short-course radiotherapy followed by intensified consolidation chemotherapy with FOLFOXIRI regimen and surgery. Primary endpoint is pCR. Among the first 11 patients who started consolidation chemotherapy, a preliminary safety analysis showed a high rate of grade 3 to 4 neutropenia (N = 7, 64%) during the first cycle of FOLFOXIRI. Therefore, the protocol has been emended with the recommendation to omit irinotecan during the first cycle of consolidation chemotherapy. After amendment, in a subsequent safety analysis focused on the first 9 patients treated with FOLFOX as first cycle and then with FOLFOXIRI, grade 3 to 4 neutropenia was reported in only one case during the second cycle. AIM OF THE STUDY: The aim of this study is to assess the safety and activity of a TNT strategy including SCRT, intensified consolidation treatment with FOLFOXIRI and delayed surgery. After protocol amendment, the treatment seems feasible without safety concern. Results are expected at the end of 2024.

Primary Tumor Resection in Synchronous Metastatic Colorectal Cancer Patients Treated with Upfront Chemotherapy plus Bevacizumab: A Pooled Analysis of TRIBE and TRIBE2 Studies.

BACKGROUND: The decision to resect or not the primary tumor in asymptomatic patients with synchronous metastatic colorectal cancer (mCRC) is a complex and challenging issue for oncologists, especially when an antiangiogenic-based therapy is planned. METHODS: Patients enrolled in the phase III TRIBE and TRIBE2 studies that compared upfront FOLFOXIRI + bevacizumab to FOLFIRI or FOLFOX + bevacizumab, respectively, were included. We assessed the association of primary tumor resection (PTR) with progression-free survival (PFS), overall survival (OS), response rate (ORR), rate of grade > 2 adverse events (AEs), and serious gastrointestinal and surgical AEs in the overall population and according to the treatment arm. RESULTS: Of the 999 patients included, 513 (51%) underwent PTR at baseline. Longer PFS and OS were observed in resected patients compared to those with unresected primary tumors: 11.2 vs. 10.0 months (p < 0.001) and 26.6 vs. 22.5 (p < 0.001), respectively. In multivariate models, PTR was confirmed as an independent prognostic factor for better PFS (p = 0.032) and OS (p = 0.018). Patients with PTR experienced a higher incidence of grade 3 or 4 diarrhea (p = 0.055) and lower incidence of anemia (p = 0.053), perforation (p = 0.015), and serious gastrointestinal and surgical AEs (p < 0.001). No statistically significant differences were noted in incidence of bleeding (p = 0.39). The benefit of FOLFOXIRI + bevacizumab in terms of PFS (p for interaction: 0.46), OS (p for interaction: 0.80), ORR (p for interaction: 0.36), and incidence of grade 3 or 4 AEs was independent of PTR. CONCLUSIONS: PTR at baseline was independently associated with good prognosis in synchronous mCRC patients and with lower incidence of serious gastrointestinal and surgical AEs during upfront chemotherapy plus bevacizumab. The benefit and toxicity profile of FOLFOXIRI plus bevacizumab was independent of PTR.

Adverse events during first-line treatments for mCRC: The Toxicity over Time (ToxT) analysis of three randomised trials.

BACKGROUND: In clinical trials, the assessment of safety is traditionally focused on the overall rate of high-grade and serious adverse events (AEs). A new approach to AEs evaluation, taking into account chronic low-grade AEs, single patient's perspective, and time-related information, such as ToxT analysis, should be considered especially for less intense but potentially long-lasting treatments, such as maintenance strategies in metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: We applied ToxT (Toxicity over Time) evaluation to a large cohort of mCRC patients enroled in randomised TRIBE, TRIBE2, and VALENTINO studies, in order to longitudinally describe AEs throughout the whole treatment duration and to compare AEs evolution over cycles between induction and maintenance strategies, providing numerical and graphical results overall and per single patient. After 4-6 months of combination therapy, 5-fluorouracil/leucovorin (5-FU/LV) + bevacizumab or panitumumab was recommended in all studies except for the 50% of patients in the VALENTINO trial who received panitumumab alone. RESULTS: Out of 1400 patients included, 42% received FOLFOXIRI (5-FU/LV, oxaliplatin, and irinotecan)/bevacizumab, 18% FOLFIRI/bevacizumab, 24% FOLFOX/bevacizumab, 16% FOLFOX/panitumumab. Mean grade of general and haematological AEs was higher in the first cycles, then progressively decreasing after the end of induction (p < 0.001), and always remaining at the highest levels with FOLFOXIRI/bevacizumab (p < 0.001). Neurotoxicity became more frequent over the cycles with late high-grade episodes (p < 0.001), while the incidence but not the grade of hand-and-foot syndrome gradually increased (p = 0.91). Anti-VEGF-related AEs were more severe in the first cycles, then setting over at low levels (p = 0.03), while anti-EGFR-related AEs still affected patients during maintenance. CONCLUSIONS: Most of chemotherapy-related AEs (except for HFS and neuropathy) reach the highest level in the first cycles, then decrease, probably due to their active clinical management. Transition to maintenance allows relief from most AEs, especially with bevacizumab-based regimens, while anti-EGFR-related AEs may persist.

Molecular screening with liquid biopsy for anti-EGFR retreatment in metastatic colorectal cancer: preliminary data from the randomized phase 2 PARERE trial.

Background: Retreatment with anti-EGFR monoclonal antibodies is a promising strategy in patients with RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC) who achieved benefit from previous anti-EGFR exposure upon exclusion of mutations in RAS/BRAF genes according to circulating tumor DNA (ctDNA) analysis by means of liquid biopsy (LB). This treatment approach is now being investigated in the randomized phase II trial PARERE (NCT04787341). We here present preliminary findings of molecular screening. Methods: Patients with RAS/BRAFV600E wt mCRC according to tissue genotyping who benefited from previous anti-EGFR-based treatment (fluoropyrimidines, oxaliplatin, irinotecan, and antiangiogenics) and then experienced disease progression to EGFR targeting were eligible for screening in the PARERE trial. The next-generation sequencing (NGS) panel Oncomine™ was employed for ctDNA testing. Results: A total of 218 patients underwent LB, and ctDNA sequencing was successful in 201 of them (92%). RAS/BRAFV600E mutations were found in 68 (34%) patients and were mainly subclonal (median variant allele fraction [VAF] for KRAS, NRAS, and BRAF mutant clones: 0.52%, 0.62%, and 0.12%, respectively; p = 0.01), with KRASQ61H being the most frequently detected (31%). Anti-EGFR-free intervals did not predict ctDNA molecular status (p = 0.12). Among the 133 patients with RAS/BRAFV600E wt tumors according to LB, 40 (30%) harbored a mutation in at least another gene potentially implied in anti-EGFR resistance, mainly with subclonal expression (median VAF, 0.56%). In detail, alterations in PIK3CA, FBXW7, GNAS, MAP2K, ERBB2, BRAF (class I and II non-BRAFV600E), SMAD, EGFR, AKT1, and CTNNB1 occurred in 13%, 8%, 7%, 3%, 2%, 2%, 1%, 1%, 1%, and 1% cases, respectively. Co-mutations were detected in 13 (33%) out of 40 patients. Conclusions: This is the largest prospective cohort of mCRC patients screened with LB for anti-EGFR retreatment in a randomized study. ctDNA genotyping reveals that at least one out of three patients candidate for retreatment should be excluded from this therapy, and other potential drivers of anti-EGFR resistance are found in approximately one out of three patients with RAS/BRAFV600E wt ctDNA.

The Evolving Landscape of Immunotherapy in Locally Advanced Rectal Cancer Patients.

Standard treatments of localized rectal cancer are surgery or the multimodal approach with neoadjuvant treatments (chemo-radiotherapy, short-course radiotherapy, induction, or consolidation chemotherapy) followed by surgery. In metastatic colorectal cancer (mCRC), immune checkpoint inhibitors (ICIs) are now the first choice in patients with a deficient mismatch repair system/microsatellite instability (dMMR/MSI-H) and are being explored in combination with chemotherapy to rewire the immune system against malignant cells in subjects with proficient mismatch repair system/microsatellite low (pMMR/MSI-L) cancers, with promising signals of efficacy. Recently, some efforts have been made to translate ICIs in earlier stages of CRC, including localized rectal cancer, with breakthrough efficacy and an organ preservation rate of mono-immunotherapy in dMMR/MSI-H patients and promising anti-tumor activity of immunotherapy plus neoadjuvant (chemo)radiotherapy in pMMR/MSI-L subjects. Here, we present the rationale, results, and limitations of the most remarkable trials assessing ICIs in dMMR/MSI-H and pMMR/MSI-L localized rectal cancer patients, at the same time highlighting the most promising research perspectives that have followed these studies.

Immune-Checkpoint Inhibitors (ICIs) in Metastatic Colorectal Cancer (mCRC) Patients beyond Microsatellite Instability.

Immune-checkpoint inhibitors (ICIs) showed impressive results in terms of activity and efficacy in metastatic colorectal cancer (mCRC) patients bearing tumors with deficient mismatch repair (dMMR) or high microsatellite instability (MSI-H). Despite that microsatellite status is the major predictive biomarker for the efficacy of ICIs, a proportion of dMMR/MSI-H mCRC tumors do not achieve benefit from immunotherapy due to the primary resistance. Deeper knowledge of biological mechanisms regulating dMMR/MSI-H CRC tumors and immune response may be useful to find new predictive biomarkers of ICIs benefit and tailor the use of immunotherapy even in dMMR/MSI-H mCRC patients. Moreover, several issues are still open, such as the secondary resection of metastases and the optimal duration of ICIs therapy in dMMR/MSI-H mCRC patients. Looking beyond microsatellite status, in a future perspective, several tools (i.e., Tumor Mutational Burden and PD-L1 expression) have been investigated to clarify their possible role as predictive biomarkers. Furthermore, a small subgroup of pMMR/MSS CRC tumors with a POLE mutation of the proofreading domain is characterized by hypermutated phenotype and might derive benefit from immune checkpoint inhibition. In the present work, we aim to review the most recent literature regarding treatment with ICIs in mCRC, focusing on dMMR/MSI-H and special subgroups of CRC patients. Hence, we summarize possible future targets and the most promising predictive biomarkers.

Surgery combined with intra-operative microwaves ablation for the management of colorectal cancer liver metastasis: A case-matched analysis and evaluation of recurrences.

Background: Hepatic resection is the only chance of cure for a subgroup of patients with colorectal cancer liver metastasis. As the oncologic outcomes of intra-operative microwaves ablation combined with hepatic resection still remain uncertain in this setting, we aimed to compare this approach with surgery alone in patient's candidate to metastases resection with radical intent. Methods: Using a case-matched methodology based on age, gender, American Society of Anesthesiology score, Body Mass Index, and burden that take in consideration the number and maximum size of lesions, 20 patients undergoing hepatic resection plus intra-operative microwaves (SURG + IMW group) and 20 patients undergoing hepatic resection alone (SURG group), were included. Relapse-free Survival and post-resection Overall Survival were compared between patients of two groups. Results: At the median follow up of 22.4 ± 17.8, 12/20 patients (60%) in SURG +IMW group and 13/20 patients (65%) in the SURG group experienced liver metastasis recurrence (p=0.774). None of them had recurrence at the same surgical or ablation site of the first hepatic treatment. 7/12 patients in the SURG+IMW group and 7/13 patients in the SURG group underwent at least one further surgical treatment after relapse (p = 1.000). No difference was reported between the two groups in terms of Relapse-free Survival (p = 0.685) and post-resection Overall Survival (p = 0.151). The use of intra-operative microwaves was not an independent factor affecting Relapse-free Survival and post-resection Overall Survival at univariate and multivariate analysis. Conclusions: Patients with colorectal cancer liver metastasis undergoing surgery plus intra-operative microwaves have similar post-operative results compared with surgery alone group. The choice between the two approaches could be only technical, depending on the site, number, and volume of the metastases. This approach could also be used in patients with liver metastasis relapse who have already undergone hepatic surgery.

Early modulation of Angiopoietin-2 plasma levels predicts benefit from regorafenib in patients with metastatic colorectal cancer.

BACKGROUND: No biomarkers are currently available to predict the efficacy of trifluridine/tipiracil (FTD/TPI) in chemorefractory metastatic colorectal cancer. The multicohort REGOLAND study aims at exploring and validating circulating markers potentially able to predict benefit from regorafenib in this setting. MATERIAL AND METHODS: In the retrospective 'regorafenib exploratory cohort', including 105 patients treated with regorafenib, baseline (d1) plasma levels of angiogenesis-related biomarkers and their early modulation after 15 days (d15) of treatment were investigated for correlation with clinical outcome. Based on a pre-specified statistical hypothesis, main retrospective findings were prospectively challenged in the 'regorafenib validation cohort', including 100 patients treated with regorafenib. Prospectively validated putative biomarkers were then assessed in the control 'FTD/TPI cohort', including 93 patients treated with FTD/TPI. RESULTS: In the 'regorafenib exploratory cohort', the early (d15) increase of Angiopoietin-2 (Ang-2) was associated with longer progression-free survival (HR:0.57 [95%CI:0.38-0.88], P = 0.004) and a trend towards longer OS (HR:0.74 [95%CI:0.48-1.14], P = 0.165), than the early decrease. Similar results were prospectively confirmed in the 'regorafenib validation cohort' (HR for progression-free survival:0.72 [95%CI:0.48-1.08], P = 0.095; HR for OS:0.77 [95%CI:0.51-1.16], P = 0.204). No predictive impact was shown for the early modulation of Ang-2 in the 'FTD/TPI cohort'. High baseline Ang-2 levels predict poor prognosis in all the investigated cohorts, independently of other clinical prognostic variables. CONCLUSIONS: The early modulation of circulating Ang-2 predicts the efficacy of regorafenib. Baseline Ang-2 plasma levels are an independent prognostic biomarker in chemorefractory metastatic colorectal cancer.

Circulating Tumor DNA as a Marker of Minimal Residual Disease After Radical Resection of Colorectal Liver Metastases.

PURPOSE: Prognostic tools to estimate the risk of relapse for patients with liver-limited metastatic colorectal cancer (LL-mCRC) undergoing resection with curative intent are needed. Circulating tumor DNA (ctDNA) as a surrogate of postsurgical minimal residual disease is a promising marker in localized CRC. We explored the role of postoperative ctDNA as a marker of minimal residual disease in patients with radically resected LL-mCRC. MATERIALS AND METHODS: Seventy-six patients with LL-mCRC were retrospectively included. DNA from tumor tissue was sequenced, and one somatic mutation was then assessed by digital droplet polymerase chain reaction in plasma samples collected after surgery to identify the persistence of ctDNA. Relapse-free survival and postresection overall survival were compared between patients with positive vs negative postoperative ctDNA. RESULTS: ctDNA was found in 39 (51%) of 76 patients with LL-mCRC. At a median follow-up of 77 months, 33 of 39 ctDNA-positive patients and 20 of 37 ctDNA-negative patients experienced disease relapse (P = .008). ctDNA-positive patients reported significantly shorter RFS than ctDNA-negative ones (median RFS 12.7 v 27.4 months hazard ratio, 2.09, P = .008). In the multivariable model including other prognostic covariates, this association was still significant (P = .046) and a trend toward shorter overall survival among ctDNA-positive patients was reported (hazard ratio, 1.65, P = .183). CONCLUSION: The detection of postsurgical ctDNA is an independent negative prognostic marker and identifies patients at high risk of relapse after liver metastases resection.