Treatments after Immune Checkpoint Inhibitors in Patients with dMMR/MSI Metastatic Colorectal Cancer

Background: Several studies reported improved outcomes with conventional treatments (CT, i.e., chemotherapy ± targeted therapy) administered after immune checkpoints inhibitors (ICI) in certain tumor types. No data are available concerning patients (pts) with metastatic colorectal cancer (mCRC) harboring mismatch repair deficiency/microsatellite instability (dMMR/MSI). We aimed to assess the outcomes of dMMR/MSI mCRC pts receiving CT after ICI failure. Methods: We conducted a retrospective multicenter study investigating the outcomes of all dMMR/MSI mCRC pts who received post-ICI CT between 2015 and 2020. Results: 31 pts (male 61%, median age 56 years) were included. ICI was an anti-PD(L)1 monotherapy in 71% of pts, and 61% received >2 lines before post-ICI CT. The overall response rate and disease control rate were 13% and 45%, with a median progression-free survival (PFS) and overall survival of 2.9 and 7.4 months, respectively. No association of the outcomes with either ICI efficacy or anti-angiogenic agents was observed. Prolonged PFS (range 16.1–21.3 months) was observed in 4 pts (13%). Conclusions: Although conducted on a limited number of patients, our results do not support an association of previous ICI treatment with an enhanced efficacy of CT in dMMR/MSI mCRC. However, prolonged disease control was observed in several cases, suggesting that some pts might derive an unexpected benefit from post-ICI treatments.

Efficacy, safety and prognostic factors in patients with refractory metastatic colorectal cancer treated with trifluridine/tipiracil plus bevacizumab in a real-world setting

We evaluated the efficacy and safety of trifluridine/tipiracil (TAS-102) plus bevacizumab in treating refractory metastatic colorectal cancer (mCRC) in a retrospective, observational study. Patients refractory or intolerant to standard therapies received TAS-102 (30–35 mg/m2 twice daily on days 1–5 and days 8–12 every 28 days) plus bevacizumab 5 mg/kg on days 1 and 15. Clinical and pathological characteristics, overall response rate (ORR) and disease control rate (DCR), overall survival (OS) and progression-free survival (PFS) data were collected and analysed. Thirty-five patients were treated from July 2019 to October 2021 (median age 64 years). The majority of patients (68.6%) were receiving TAS-102 plus bevacizumab as third-line treatment. Patients received a median of 4 (range 2–15) cycles of treatment. Among 31 patients evaluable for response (88.6%), ORR and DCR were 3.2% and 51.6%, respectively. After a median 11.6 months’ follow-up, median PFS was 4.3 (95% confidence interval [CI] 3.4–5.1) months and median OS was 9.3 (95% CI 6.6–12.1) months. The most common grade 3–4 toxicities were neutropenia, asthenia and nausea/vomiting, and there were no treatment-related deaths. This real-world study confirms the efficacy and safety of TAS-102 plus bevacizumab in patients with refractory mCRC.

Delta Tocotrienol as a Supplement to FOLFOXIRI in First Line Treatment of Metastatic Colorectal Cancer. A Randomized, Double-blind, Placebo-controlled Phase II Study

Purpose Triplet chemotherapy might be more effective than doublet chemotherapy in metastatic colorectal cancer (mCRC), but it may also be marked by increased toxicity. To investigate whether δ-tocotrienol, a vitamin E analogue, with its possible neuroprotective and anti-inflammatory effects reduces the toxicity of triplet chemotherapy, we conducted a randomized, double-blind, placebo controlled trial in mCRC patients receiving first line 5-fluorouracil, oxaliplatin and irinotecan (FOLFOXIRI).Methods We randomly assigned 70 mCRC patients to FOLFOXIRI plus δ-tocotrienol or FOLFOXIRI plus placebo. FOLFOXIRI was given in eight cycles followed by four cycles of 5-fluorouracil. δ-tocotrienol 300 mg or placebo x 3 daily was added during chemotherapy and for a maximum of two years. The primary endpoint was time to hospitalization or death during treatment with chemotherapy.Results Median time to first hospitalization or death was 3.7 months in the placebo group (95% CI 1.93-not reached (NR)), and NR in the δ-tocotrienol group (95% CI 1.87-NR) with a hazard ratio (HR) of 0.70 (95% CI 0.36-1.36, p=0.29)). In the placebo group 24 patients (71%) had oxaliplatin dose reductions compared to 17 patients (47%) in the δ-tocotrienol group (p=0.047).Conclusion The addition of δ-tocotrienol to FOLFOXIRI did not significantly prolong the time to first hospitalization or death compared to FOLFOXIRI plus placebo. Toxicity was manageable and not statistically different between the two groups. There was a statistically significant difference in dose reductions of oxaliplatin pointing to a possible neuroprotective effect of δ-tocotrienol.Clinicaltrials.gov identifier NCT02705300. Date of registration March 10, 2016.

Next Generation Sequencing of Circulating Tumor DNA Can Optimize Second Line Treatment in RAS Wild Type Metastatic Colorectal Cancer after Progression on Anti-EGFR Therapy: Time to Rethink Our Approach

Background Management of Raswild-type colorectal cancer (CRC) patients upon disease progression after the successful use of targeted treatment with anti-EGFR monoclonal antibodies and backbone chemotherapy remains a clinical challenge. Development of treatment resistance with prevalence of pre-existing RAS mutated clones, RAS mutation conversion, truncation of extracellular receptor domains as well as HER2 and MET amplification are molecular events that can be difficult to follow without the use of sophisticated laboratory techniques. Summary The clinical hurdle of re-biopsy and tumor heterogeneity can be overcome by the implementation Next Generation Sequencing (NGS) to analyze circulating tumor DNA (ctDNA) and identify drugable mutations or recovery of RAS-wildness. In this opinion paper we summarize with critical thinking the clinical approach to be followed after the failure of first line treatment in Ras wild-type CRC tumors with the use of NGS. Key Messages Rechallenge with anti-EGFR inhibitors, in case of persistent or recovery of Ras wildness, and targeted approach of specific mutations (BRAF inhibitors) amplifications (anti-Her2 treatment) or fusion proteins (NTRK inhibitors) can by guided by the use of NGS. The use of NGS platforms for serial analysis of ctDNA is an important step to better understand the molecular landscape of metastatic colorectal cancer and guide clinical decisions. NGS should be considered a mainstay in clinical practice for the management of CRC patients and health authorities should consider reimbursing its use in the appropriate clinical settings.

Efficacy of apatinib combined with FOLFIRI in the first-line treatment of patients with metastatic colorectal cancer

SummaryObjective. To evaluate the efficacy and safety of apatinib combined with FOLFIRI in the first-line treatment of advanced metastatic colorectal cancer (mCRC) and explore potential factors of efficacy. Methods. Twenty mCRC patients treated at Affiliated Cancer Hospital of Shanxi Medical University from March 2017 to March 2019 were included according to the enrolment criteria. They provided informed consent and were treated with apatinib combined with FOLFIRI according to the scheduled regimen until disease progression or unacceptable toxicity occurred. The primary endpoint was OS. The secondary endpoints included PFS, ORR, DCRand safety. OS and PFS were calculated using Kaplan–Meier curves. Univariate and multivariate Cox regression analyses were used to evaluate independent prognostic factors of OS and PFS. R was used to determine cut-off values for biochemical indicators. Forest maps were drawn for Cox univariate results and the relationships between NLR and ECOG, which were significant in univariate analysis, and OS were represented by Kaplan–Meier curves. Results. The median OS and PFS were 16.135 months (95% CI: 9.211–22.929) and 6 months (95% CI: 5.425–6.525). Multivariate Cox analysis showed that NLR and CEA were independent prognostic factors. The most common grade 3–4 adverse events were hypertension, diarrhoea, increased alkaline phosphatase, decreased leukocytes and decreased neutrophils. Conclusion. Apatinib combined with FOLFIRI for the first-line treatment of advanced unresectable mCRC showed good efficacy and safety. The baseline NLR was predictive of efficacy, and a low baseline NLR (HR: 0.2895, P = 0.0084) was associated with improved OS.Clinical Research Registration Number: ChiCTR1800015308.