Second-line treatment strategies for RAS wild-type colorectal cancer: A systematic review and Network Meta-analysis (NMA)

BACKGROUND

The optimal strategy for second-line (IIL) treatment in KRAS wt metastatic colorectal cancer (mCRC) is not determined yet.

METHODS

A random-effect NMA of phase II/III RCTs was conducted to evaluate IIL treatment for all-RAS wt mCRC, comparing anti-EGFR or anti-VEGF, and chemotherapy (CT).

RESULTS

Overall, 11 RCTs (3613 patients) were included. In KRAS wt patients, PFS was improved with anti-VEGF (HR 0.43) and anti-EGFR (HR 0.63) vs CT. However, anti-VEGF based therapy had the highest likelihood of being ranked as the best treatment in terms of PFS (SUCRA 99.3%) and OS (SUCRA 99.4%). Bevacizumab-based treatment is most likely to be the best treatment in terms of PFS (SUCRA 89.1%) and OS (SUCRA 86.7%).

CONCLUSIONS

Second line treatment with anti-VEGF and anti-EGFR improved PFS in mCRC patients, however, anti-VEGF based therapy, particularly CT plus bevacizumab, is the best treatment according to SUCRA in terms of PFS and OS.

Liquid biopsy in colorectal cancer: Onward and upward

Colorectal cancer (CRC) remains a leading cause of cancer-related deaths worldwide. In recent years, liquid biopsy has emerged as one of the most interesting areas of research in oncology, leading to innovative trials and practical changes in all aspects of CRC management. RNAs and cell free DNA (cfDNA) methylation are emerging as promising biomarkers for early diagnosis. Post-surgical circulating tumour DNA (ctDNA) can aid in evaluating minimal residual disease and personalising adjuvant treatment. In rectal cancer, ctDNA could improve response assessment to neoadjuvant therapy and risk stratification, especially in the era of organ-preservation trials. In the advanced setting, ctDNA analysis offers the opportunity to monitor treatment response and identify driver and resistance mutations more comprehensively than traditional tissue analysis, providing prognostic and predictive information. The aim of this review is to provide a detailed overview of the clinical applications and future perspectives of liquid biopsy in CRC.

Preoperative treatments in borderline resectable and locally advanced pancreatic cancer: current evidence and new perspectives

Surgery is the only curative treatment for non-metastatic pancreatic adenocarcinoma, but less than 20% of patients present a resectable disease at diagnosis. Treatment strategies and disease definition for borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC) vary in the different cancer centres. Preoperative chemotherapy (CT) is the standard of care for both BRPC and LAPC patients, however literature data are still controversial concerning the type, dose and duration of the different CT regimens, as well as regarding the integration of radiotherapy (RT) or chemoradiation (CRT) in the therapeutic algorithm. In this unsettled debate, we aimed at focusing on the therapeutic regimens currently in use and relative literature data, to report international trials comparing the available therapeutic options or explore the introduction of new pharmacological agents, and to analyse possible new scenarios in microenvironment evaluation before and after neoadjuvant therapies or in patients' selection at a molecular level.

The SAFFO Study: Sex-Related Prognostic Role and Cut-Off Definition of Monocyte-to-Lymphocyte Ratio (MLR) in Metastatic Colorectal Cancer

Background: Emerging data suggest that gender-related immune system composition affects both immune response and efficacy of immunotherapy in cancer patients (pts). This study aimed to investigate the sex-related prognostic role of MLR in metastatic colorectal cancer (mCRC) pts. Methods: We analyzed a retrospective consecutive cohort of 490 mCRC patients treated from 2009 to 2018 at the Oncology Departments of Aviano and Pordenone (training set) and Udine (validation set), Italy. The prognostic impact of MLR on overall survival (OS) was evaluated with uni- and multivariable Cox regression models. The best cut-off value to predict survival was defined through ROC analyses. Results: Overall, we identified 288 males (59%) and 202 females (41%); 161 patients (33%) had a right-sided, 202 (42%) a left-sided primary, and 122 (25%) a rectal tumor. Interestingly, gender was associated with MLR (p = 0.004) and sidedness (p = 0.006). The obtained cut-off value for MLR in females and males was 0.27 and 0.49, respectively. According to univariate analysis of the training set, MLR (HR 9.07, p ≤ 0.001), MLR > 0.27 in females (HR 1.95, p = 0.003), and MLR > 0.49 in males (HR 2.65, p = 0.010) were associated with poorer OS, which was also confirmed in the validation set. In multivariate analysis, MLR > 0.27 in females (HR 2.77, p = 0.002), MLR > 0.49 in males (HR 5.39, p ≤ 0.001), BRAF mutation (HR 3.38, p ≤ 0.001), and peritoneal metastases (HR 2.50, p = 0.003) were still independently associated with worse OS. Conclusions: Males and females have a different immune response. Our study showed that high MLR, both in males and females, is an unfavorable Independent prognostic factor. Further prospective studies are needed to confirm these data.

LDH as prognostic factor in second line treatment for advanced gastric cancer: The LINE study

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Background: Lactate dehydrogenase (LDH) is recognized as indirect marker of tumor hypoxia and angiogenesis for several solid tumors. Ramucirumab is the first antiangiogenic agent approved for second-line therapy in advanced gastric cancer (GC), alone or in association with chemotherapy. To date, no reliable biomarkers can predict the potential benefit from anti-VEGFR2 treatment. This retrospective multicenter study aimed to assess the prognostic role of baseline LDH levels in patients (pts) undergoing second-line treatment for advanced GC. Methods: The study analyzed a retrospective cohort of consecutive advanced GC pts treated with second line therapy at IRCCS, CRO of Aviano and at Mauriziano Hospital of Torino, Italy, from 2010 to 2020. LDH levels prior to second-line treatment were classified as low-normal or high and standardized according to the upper limit of the reference range. To better determine the optimal LDH cut-off value, ROC analysis was performed (using PFS < 3 months as binary outcome). Normalized LDH values were subsequently sorted according to the ROC curve cut-off in order to test the association with overall survival (OS) through the Kaplan-Meier method and compared using the Log-Rank test. A multivariate Cox regression analysis assessed the prognostic impact of normalized LDH levels for OS calculated from the start of second line treatment. Results: Overall, 125 pts were enrolled. Of these, 81 pts (64.80%) received ramucirumab alone or plus paclitaxel as second line treatment, while 44 (35.20%) had taxanes or fluoropyrimidines combined with irinotecan. Median age was 68 years, 93% had an ECOG PS ≤ 1, 64.80% was first diagnosed with metastatic disease and 40.80% underwent primary tumor resection. Median second line PFS and OS were 4.2 and 7.9 months, respectively. Baseline LDH values were available for 99 pts. ROC analysis identified a normalized LDH value of 0.83 as the optimized cut-off point to define pts with poor prognosis. At univariate analyses, surgery of the primary tumor (HR 0.51, 95% CI 0.31-0.82, p = 0.005) was associated with better OS, while low-normal BMI ( < 25 kg/m2) at second line start (HR 1.99, 95% CI 1.21-3.28, p = 0.007), normalized LDH values ≥ 0.83 (HR 1.86, 95% CI 1.13-3.07, p = 0.015) and PS > 1 (HR 5.65, 95% CI 2.29-13.92, p < 0.001) were associated with poorer outcome. At multivariable model, only PS > 1 was independently associated with poor prognosis (HR 9.93, 95% CI 3.27-30.08, p < 0.001). Subgroup analyses showed no significant heterogeneity in OS outcome according to normalized LDH levels between patients treated with or without ramucirumab. Conclusions: Elevated LDH levels are indicators of worse outcome in advanced gastric cancer pts. Notably, the LDH cut-off value identified a poor prognosis subgroup among pts with normal baseline levels, suggesting that current laboratory ranges could be suboptimal for patient stratification.

Glycolytic competence in gastric adenocarcinomas negatively impacts survival outcomes of patients treated with salvage paclitaxel-ramucirumab

INTRODUCTION

For energy production, cancer cells maintain a high rate of glycolysis instead of oxidative phosphorylation converting glucose into lactic acid. This metabolic shift is useful to survive in unfavorable microenvironments. We investigated whether a positive glycolytic profile (PGP) in gastric adenocarcinomas may be associated with unfavorable outcomes under an anticancer systemic therapy, including the anti-angiogenic ramucirumab.

MATERIALS AND METHODS

Normal mucosa (NM) and primary tumor (PT) of 40 metastatic gastric adenocarcinomas patients who received second-line paclitaxel-ramucirumab (PR) were analyzed for mRNA expression of the following genes: HK-1, HK-2, PKM-2, LDH-A, and GLUT-1. Patients were categorized with PGP when at least a doubling of mRNA expression (PT vs. NM) in all glycolytic core enzymes (HK-1 or HK-2, PKM-2, LDH-A) was observed. PGP was also related to TP53 mutational status.

RESULTS

Mean LDH-A, HK-2, PKM-2 mRNA expression levels were significantly higher in PT compared with NM. 18 patients were classified as PGP, which was associated with significantly worse progression-free and overall survival times. No significant association was observed between PGP and clinical-pathologic features, including TP53 positive mutational status, in 28 samples.

CONCLUSIONS

Glycolytic proficiency may negatively affect survival outcomes of metastatic gastric cancer patients treated with PR systemic therapy. TP53 mutational status alone does not seem to explain such a metabolic shift.

Individual Patient Data Meta-Analysis of FOLFOXIRI Plus Bevacizumab Versus Doublets Plus Bevacizumab as Initial Therapy of Unresectable Metastatic Colorectal Cancer

PURPOSE

A proper estimation of the magnitude of the overall survival (OS) benefit from infusional fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI) plus bevacizumab versus doublets + bevacizumab is lacking because all trials that have investigated this regimen had primary end points other than OS. To test OS with higher power and to explore the interaction of treatment effect with main patient and disease characteristics, we performed an individual patient data (IPD) meta-analysis.

PATIENTS AND METHODS

IPD from 5 eligible trials were collected: CHARTA (ClinicalTrials.gov identifier: NCT01321957), OLIVIA (ClinicalTrials.gov identifier: NCT00778102), STEAM (ClinicalTrials.gov identifier: NCT01765582), TRIBE (ClinicalTrials.gov identifier: NCT00719797), and TRIBE2 (ClinicalTrials.gov identifier: NCT02339116). The primary end point was OS. Secondary end points were progression-free survival (PFS), objective response rate (ORR), R0 resection rate, grade 3/4 adverse events, and subgroup analyses according to clinical and molecular characteristics.

RESULTS

A total of 1,697 patients were randomly assigned to FOLFOXIRI + bevacizumab (n = 846) or doublets + bevacizumab (n = 851). Most (78%) had an Eastern Cooperative Oncology Group performance status of 0, and the median age was 61 years. After a median follow-up of 39.9 months, patients assigned to FOLFOXIRI + bevacizumab had significantly longer OS than those assigned to doublets + bevacizumab (median, 28.9 v 24.5 months; hazard ratio [HR], 0.81; 95% CI, 0.72 to 0.91; P < .001), with no significant heterogeneity among trials (P = .39; I2 = 2%). No significant interaction effect between treatment arm and investigated characteristics was demonstrated. Patients assigned to FOLFOXIRI + bevacizumab had longer PFS (median, 12.2 v 9.9 months; HR, 0.74; 95% CI, 0.67 to 0.82; P < .001), higher ORR (64.5% v 53.6%; P < .001), higher R0 resection rate (16.4% v 11.8%; P = .007), and higher rates of grade 3/4 neutropenia (45.8% v 21.5%; P < .001), febrile neutropenia (6.3% v 3.7%; P = .019), and diarrhea (17.8% v 8.4%; P < .001).

CONCLUSION

FOLFOXIRI + bevacizumab significantly and meaningfully improves survival of patients with metastatic colorectal cancer compared with doublets + bevacizumab and provides advantage in PFS, ORR, and R0 resection rate at the price of a moderate increase in toxicity. No increased benefit is observed among patients with BRAF-mutant tumors.

Determinants of choice in offering drug holidays during first-line therapy for metastatic colorectal cancer

Background: 'Drug holidays' (DH) for metastatic colorectal cancer (mCRC) were introduced to preserve quality of life. We studied factors associated to a DH offer in first line. Materials & methods: We retrospectively analyzed 754 consecutive patients treated with chemotherapy for mCRC in two Italian institutions between 2005 and 2017. Associations between baseline clinical-pathological factors and DH (56 or more days of treatment interruption) were investigated. Results: In 754 patients, previous metastasectomy, previous thermoablation and previous surgery of primary tumor were independently associated with DH. Excluding procedures or clinical trials: primary rectal cancer and resection of primary tumor were significantly associated to DH. Conclusions: DH was offered to patients with lower burden of disease, but further investigations are needed to safely guide a holiday strategy.

Prognostic role of macrophage infiltration and monocyte-to-lymphocyte ratio in stage III colon cancer: The MIRROR study

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Background: Changes in peripheral blood cells composition may reflect immune microenvironment and its role in cancer growth. High monocyte-to-lymphocyte ratio (MLR) could be a marker of tumor’s recruitment of suppressive cells, showing a prognostic role. This study aimed to assess the prognostic impact of macrophage infiltration and MLR in stage III colon cancer (CC) patients (pts). Methods: This multicentric study retrospectively analyzed a consecutive cohort of 423 CC pts treated between 2008-2019 at the Cancer Centre of Aviano (Italy) (n = 300) and at the European Georges Pompidou Hospital of Paris (France) (n = 123). The association of MLR with disease-free survival (DFS) and overall survival (OS) was evaluated with Cox regression analyses. Random Forrest was implemented on python using h2oai. Performance was assessed in terms of accuracy (ACC) and Matthews Coefficient (MCC). Analyses was adjusted on classical prognostic factors of stage III CC such as pT, pN, grade, location, ECOG PS. Results: Overall, 77% had pT1-3, 30% pN2 and 73% G1-2 tumors. Interestingly, 25% had a lymphatic and vascular invasion, 42/230 (18%) had MSI status, 69/152(45%) and 19/114 (13%) were KRAS and BRAF mutant. 56% had CEA > 5. Pts were treated with fluoropyrimidine and oxaliplatin as adjuvant therapy. Notably, 130 cases were analyzed according to lymphocytic and macrophage infiltration (CD163, CD68, CD3, CD8). Of them, 78% had a CD163/CD8 ratio ≤3 and 74% a CD8/CD3 ratio ≤1.5. At median follow-up of 57 months, median DFS and OS were not reached, 31% of pts relapsed and 23% dead. By multivariate analysis, including statistically significant prognostic variables, CD163/CD8 ratio (HR 1.15, p = 0.039, 95%C.I. 1.1-1.32) and MLR > 0.45 (HR 2.98, p = 0.008, 95%C.I. 1.33-6.67) were associated with worse DFS. By multivariate analysis for OS, including statistically significant confounding variables, MLR > 0.45 (HR4.32, P = 0.012, 95%C.I. 1.37-9) and BRAF mutation predicted worse OS. According random survival forest for OS, CD68/CD3 were the first variable of importance (0.06), followed by MLR (0.009) and CD8 (0.007). Interestingly, high MLR followed by CEA, MSI, KRAS were the features linked with organotropism on liver (ACC 0.6 ±0.3), while high MLR, KRAS, pN, pT were mainly linked with lung colonization (ACC 0.6 ±0.2). Conclusions: High pre-treatment levels of MLR and CD163/CD8 ratio in stage III CC are independently associated with worse prognosis. The present study paves the way to a prospective validation of these promising cost-effective biomarkers.

FOLFOXIRI/bevacizumab (bev) versus doublets/bev as initial therapy of unresectable metastatic colorectal cancer (mCRC): A meta-analysis of individual patient data (IPD) from five randomized trials

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Background: Several randomized trials demonstrated that intensifying the upfront chemotherapy in combination with bev is beneficial for mCRC patients with an increased incidence of some adverse events. All trials had primary endpoints other than OS, and a proper estimation of the magnitude of the OS benefit from FOLFOXIRI/bev versus doublets (FOLFIRI or FOLFOX)/bev is currently lacking. Within each trial, subgroup analyses failed to identify predictors of benefit from the intensified therapy. To test OS with higher power compared to single trials, and to explore interaction of treatment effect with main patients’ and disease characteristics, we performed an IPD meta-analysis. Methods: IPD were collected from 5 randomized trials: CHARTA (NCT01321957), OLIVIA (NCT00778102), STEAM (NCT01765582, only combined FOLFOXIRI/bev and FOLFOX/bev arms), TRIBE (NCT00719797) and TRIBE2 (NCT02339116). Primary endpoint was OS. Secondary endpoints included PFS, objective response rate (ORR), R0 resection rate, G3/4 adverse events, and subgroup analyses. All statistical analyses were by intention-to-treat, stratified by trial. Results: 1697 pts randomized to FOLFOXIRI/bev (N=846) or doublets/bev (N=851) were included. Among pts in the doublets/bev group, 595 (70%) received FOLFOX/bev and 256 (30%) FOLFIRI/bev. At a median follow up of 39.9 mos, pts assigned to FOLFOXIRI/bev reported significantly longer OS than those assigned to doublets/bev (median OS 28.9 vs 24.5 months; HR 0.81 [95%CI 0.72-0.91], p<0.001), with no significant heterogeneity among trials (p=0.39; I2=2%). The estimated 5-yr OS was 22.3% vs 10.7% (p<0.001). No significant interaction effect between treatment arm and OS was demonstrated in terms of metastatic spread (liver-limited vs. not liver-limited p=0.665), primary side (p=0.656), and RAS/BRAF status (p=0.337). Pts assigned to FOLFOXIRI/bev achieved longer PFS (median PFS 12.2 vs 9.9 months; HR 0.74 [95%CI 0.67-0.82], p<0.001), higher ORR (64.5% vs 53.6%, p<0.001), higher R0 resection rate (16.4% vs 11.8%, p=0.007), and experienced higher rates of G3/4 neutropenia (p<0.001), febrile neutropenia (p=0.019), mucositis (p=0.024), nausea (p=0.016), and diarrhea (p<0.001). Conclusions: FOLFOXIRI/bev determines a clinically and statistically significant improvement of mCRC patients’ OS vs doublets/bev with a meaningful effect also on 5-yr OS, PFS, ORR and R0 resection rate. No significant heterogeneity among explored subgroups was found.

TP53 mutation analysis in gastric cancer and clinical outcomes of patients with metastatic disease treated with anti-angiogenic or standard chemotherapy regimens

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Background: Current data support the angiogenic potential of cancer cells with mutant p53 and VEGF-A up-regulation in solid tumors. These findings have renewed interest in the p53 role as a predictive/prognostic factor in cancer therapy. We investigated TP53 mutations in gastric adenocarcinoma (GA) samples of metastatic patients (pts) who underwent anti-angiogenic Paclitaxel-Ramucirumab (PR) therapy. The analysis was also performed in a control group of pts who received first-line chemotherapy (CT) with platinum derivates and fluoropyrimidines. Methods: TP53 mutations were identified by next-generation sequencing in 110 GA primary tumors of two retrospective metastatic series including 48 pts who were treated with second-line PR and 62 pts who received first-line CT with Cisplatin or Oxaliplatin plus 5-Fluorouracil or Capecitabine. Detected TP53 mutations were classified for TP53 mutant-specific residual transcriptional activity scores ( TP53 RTAS) (Fischer NW et al JCI Insight 2018). TP53 RTAS results were used for stratifying pts in survival analyses. Primary end-point was overall survival (OS). Results: In the PR group, TP53 mutations were detected in 29 out of 48 tumor samples (60.4%) with 10 having TP53 RTAS 0%-to-<1%. In the CT group, TP53 mutations were found in 40 out of 62 tumor samples (64.5%) with 11 having TP53 RTAS 0%-to-<1%. In the PR group, the 10 cases with a TP53 mutation causing no residual or minimal activity ( TP53 RTAS 0%-to-<1%) showed better OS in comparison with pts in the remaining groups (wild-type and TP53 RTAS > 1%). This effect was retained in the multivariate model analysis (Hazard Ratio = 0.29, 95% confidence interval 0.17-0.85, p = 0.02). An opposite effect was seen in the CT group with the worst OS in carriers of TP53 RTAS 0%-to-<1% mutations (Hazard Ratio = 2.64, 95% confidence interval 1.17-5.95, p = 0.02). Notably, in the whole group of 110 pts, TP53 mutations (any type) occurred more frequently in the intestinal-type GA group (p = 0.02). Conclusions: Additional studies are warranted to explore the favorable role of TP53 mutations in cancer pts undergoing anti-angiogenic therapies. TP53 mutations frequently occur in GA and these findings would lead to novel tailored therapy strategies in this lethal disease.

The MIMIC Study: Prognostic Role and Cutoff Definition of Monocyte-to-Lymphocyte Ratio and Lactate Dehydrogenase Levels in Metastatic Colorectal Cancer

BACKGROUND

Monocyte-to-lymphocyte ratio (MLR) and lactate dehydrogenase (LDH) levels are circulating biomarkers that provide information about tumor-related inflammation and immune suppression. This study aimed to evaluate the prognostic role of MLR and LDH in metastatic colorectal cancer (mCRC).

MATERIAL AND METHODS

This multicentric study analyzed a consecutive cohort of 528 patients with mCRC treated in 2009-2017. The whole population was randomly divided in training and validation cohort. The first was used to identify a threshold for MLR and to create the prognostic model with MLR and MLR-LDH combined (group 1: MLR-LDH low; group 2: MLR or LDH high; group 3: MLR-LDH high). The second cohort was used to validate the model.

RESULTS

At the median follow-up of 55 months, median overall survival (OS) was 22 months. By multivariate analysis, high MLR >0.49 (hazard ratio [HR], 2.37; 95% confidence interval [C.I.], 1.39-4.04), high LDH (HR, 1.73; 95% C.I., 1.03-2.90) in the first model, group 2 (HR, 2.74; 95% C.I.; 1.62-4.66), and group 3 (HR, 3.73; 95% C.I., 1.94-7.18) in the combined model, had a worse prognosis in terms of OS. These data were confirmed both in the validation set and then in the whole cohort.

CONCLUSION

MLR and LDH are circulating cost-effective biomarkers, readily available in clinical practice, that can be useful for predicting the prognosis of patients with mCRC.

IMPLICATIONS FOR PRACTICE

High monocyte-to-lymphocyte ratio (MLR) and lactate dehydrogenase (LDH) levels could be a sign of a tumor's recruitment of suppressive and inflammatory cells worsening prognosis of different types of cancer, including colorectal cancer (CRC). Currently, no data are available for metastatic CRC regarding a cutoff definition for MLR or the prognostic impact of MLR and MLR-LDH combined. The present study showed in the training cohort and confirmed in the validation and whole cohort that MLR is a reliable and independent laboratory biomarker, which is easy to use, to predict clinical outcomes in patients with mCRC. Moreover, MLR and composite MLR-LDH could potentially result in an incremental improvement in the prognostic value of these biomarkers, being used as stratification tools for patients with mCRC.

Clinical and molecular determinants of extrahepatic disease progression in patients with metastatic colorectal cancer with liver-limited metastases deemed initially unresectable

Background

No tools to predict the probability of extrahepatic disease progression (ePD) of initially unresectable, liver-limited metastatic colorectal cancer (mCRC) are currently available. To estimate the likelihood to develop ePD and to identify clinical and molecular factors that could predict extrahepatic progression-free survival (ePFS), we conducted an observational, retrospective, multicentre cohort study.

Methods

We retrospectively identified a cohort of 225 patients with initially unresectable liver-limited disease (LLD), treated from January 2004 to December 2017 with first-line doublets or triplet plus a biological agent at two Italian institutions.

Results

173 (77%) patients experienced ePD which occurred within 1, 2 or 3 years from the diagnosis of mCRC in 15%, 49% and 66% of patients, respectively. Globally, 164 (73%) patients underwent a liver resection at some point of their disease history, and 54 (33%) of them underwent a subsequent locoregional treatment. Age > 70 years, locoregional nodal involvement at diagnosis of colorectal cancer and ≥4 liver metastases were significantly associated with higher risk of ePD while liver resections were associated with reduced risk of ePD. In the multivariable model, number of liver metastases (subdistribution HR, SHR 1.63, 95% CI 1.12 to 2.36; p = 0.01) and liver resections (SHR 0.43, 95% CI 0.29 to 0.63; p = 0.001) were still associated with ePD. Number of liver metastases < 4, no nodal involvement at diagnosis and liver resections were also associated with prolonged ePFS.

Conclusions

The identified clinical factors could help physicians in personalising the intensity and aggressiveness of liver-directed treatments in patients with mCRC with initially unresectable LLD.

Efficacy of retreatment with anti-EGFRs in mCRC is not predictable by clinical factors related to prior lines of therapy: A multi-institutional analysis

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Background: Retrospective analyses and phase 2 studies suggest that administering an anti-EGFR in advanced lines may be effective in mCRC pts who achieved benefit from a 1st-line anti-EGFR containing regimen. The identification of clinical features associated with benefit from anti-EGFR re-treatment (re-tx) in pts experiencing PD during 1st-line anti-EGFR (rechallenge) or after its interruption (reintroduction), is a major clinical need. Methods: A real-life data-base including a total of 5530 pts treated at 6 insitutions from December 2010 to October 2018 was queried. Pts retreated with anti-EGFRs, with RAS/ BRAF wild-type status on tissue samples, who had received a 1st-line anti-EGFR-based tx with at least SD as best response, and at least one further line of therapy before anti-EGFR re-tx, were included. The association with RECIST response (RR), PFS and OS was investigated for the following variables: RR (PR or CR vs SD) and PFS during 1st-line; time from the last anti-EGFR administration to 1st-line PD (i.e. re-introduction vs rechallenge); reason for anti-EGFR discontinuation in 1st-line (PD vs. other); number of anti-EGFR-free lines of therapy before re-tx; anti-EGFR free interval (time between the last anti-EGFR administration in 1st-line and the time of re-tx); primary tumor side; time from the diagnosis of metastatic disease to re-tx (≥ vs. < 18 mos). Results: Data from 86 patients were retrieved, 56 (65%) and 30 (35%) received anti-EGFR rechallenge or reintroduction, respectively. Median anti-EGFR free interval was 15.1 mos. The RR during re-tx was 19.8%, with a DCR of 46.5%. Median PFS and OS were 3.6 and 10.2 mos, respectively. No significant association of investigated features with RR and PFS was observed. No differences in RR or PFS were observed among patients receiving anti-EGFR re-tx as rechallenge or reintroduction (20.4% vs 23.1%, p = 0.99; median PFS: 3.49 vs 4.97 mos, p = 0.61). Patients with left-sided tumors had longer OS (HR: 0.50, 95%CI: 0.26-0.93, p = 0.005). Conclusions: Clinical factors that are generally believed to affect the efficacy of anti-EGFR re-tx are not confirmed in our series. Therefore, clinicians should not rely on those characteristics in their decision-making on anti-EGFR re-tx, and adequate studies for implementing liquid biopsy in clinical practice are urgently needed.

The IMPACT study: early loss of skeletal muscle mass in advanced pancreatic cancer patients

BACKGROUND

Pancreatic cancer (PC) patients have multiple risk factors for sarcopenia and loss of skeletal muscle mass (LSMM), which may cause greater treatment toxicities, reduced response to cancer therapy, prolonged hospitalization, impaired quality of life, and worse prognosis.

METHODS

This is a retrospective study on advanced PC patients treated at the Department of Oncology of Udine, Italy, from January 2012 to November 2017. Among 162 patients who received chemotherapy, 94 consecutive patients with an available computed tomography (CT) scan were retrospectively analyzed. The primary objective of our study was to explore if an early LSMM ≥ 10% (measured at first radiological evaluation and compared with baseline) and/or baseline sarcopenia may impact prognosis. Baseline sarcopenia was defined according to Prado's criteria. Skeletal muscle area was measured as cross-sectional areas (cm² ) using CT scan data through the Picture archiving and communication system (PACS) image system.

RESULTS

In the whole cohort, 48% of patients were ≤70 years old, and 50% had metastatic disease. At baseline, 73% of patients had sarcopenia, and 16% presented a visceral fat area ≥ 44 cm² /m² . Overall, 21% experienced an early LSMM ≥ 10%. Approximately 33% of sarcopenic patients at baseline and ~35% of patients with early LSMM ≥ 10% had a body mass index > 25 kg/m² . Of note, 71% of patients were evaluated by a nutritionist, and 56% received a dietary supplementation (oral and/or parenteral). After a median follow-up of 30.44 months, median overall survival (OS) was 11.28 months, whereas median progression-free survival (PFS) was 5.72 months. By multivariate analysis, early LSMM ≥ 10% was significantly associated with worse OS [hazard ratio (HR): 2.16; 95% confidence interval (CI) 1.23-3.78; P = 0.007] and PFS (HR: 2.31; 95% CI 1.30-4.09; P = 0.004). Moreover, an exploratory analysis showed that inflammatory indexes, such as neutrophil-lymphocyte ratio variation, impact early LSMM ≥ 10% (odds ratio 1.31, 95% CI 1.06-1.61, P = 0.010).

CONCLUSIONS

Early LSMM ≥ 10% has a negative prognostic role in advanced PC patients. Further prospective investigations are needed to confirm these preliminary data.

Benefit from anti-EGFRs in RAS and BRAF wild-type metastatic transverse colon cancer: a clinical and molecular proof of concept study

Objective

Primary tumour location is regarded as a reliable surrogate of colorectal cancer biology. Sensitivity to anti-EGFRs (Epidermal Growth Factor Receptor) of metastatic transverse colon cancers (mTCCs) has usually been assumed similar to right-sided tumours; however, evidence about the clinical behaviour of mTCC is limited. Thus, to verify sensitivity of mTCC to anti-EGFRs we conducted the present study.

Methods

Patients with RAS/BRAF wild-type microsatellite stable (MSS) mTCC receiving anti-EGFR monotherapy, or in combination with irinotecan if clearly irinotecan-refractory, were included. Hypothesising an overall response rate (ORR) of 35%, 11 patients, of whom at least 3 were responders, were necessary to be able to reject the null hypothesis of an ORR of 5%, with α and β errors of 0.05 and 0.20. PRESSING panel and consensus molecular subtypes (CMS) were assessed on tumour samples, whereas in-silico data were obtained from TCGA dataset.

Results

Among nine eligible patients, four and three achieved response and disease stabilisation (ORR 44%). At a median follow-up of 23.1 months, median progression-free survival and overall survival were 7.3 (95% CI 3.9 to NA) and 15.0 months (95% CI 10.0 to NA), respectively. A MET amplification and an ERBB4 S303F substitution were detected in patients with rapid disease progression, while others had PRESSING panel-negative tumours with CMS2 or CMS4 subtypes.

Conclusions

RAS/BRAF wild-type MSS mTCCs may be sensitive to anti-EGFRs, as confirmed by molecular analyses.

The Winding Roadmap of Biomarkers toward Clinic: Lessons from Predictors of Resistance to Anti-EGFRs in Metastatic Colorectal Cancer

In the evolving molecular landscape of metastatic colorectal cancer, optimizing available tools to select patients to receive anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies is a modern challenge of colorectal oncologists. Several molecular biomarkers have been investigated in recent years as potential predictors of resistance to anti-EGFR agents in preclinical and clinical retrospective series. Nevertheless, none of them have been implemented in clinical practice due to the lack of a formal prospective demonstration. Here, we propose a literature review of molecular alterations associated with resistance to anti-EGFRs, underlining the reasons why their roadmap from laboratories to clinics was prematurely halted.

Comparison of primary breast cancer and paired metastases: biomarkers discordance influence on outcome and therapy

AIM

Discordance between primary tumor and paired metastases biology has been widely detected in metastatic breast cancer. The aim of this study was to evaluate the prognostic impact of Ki67, estrogen receptor (ER), progesterone receptor (PR) and HER2 discordance.

METHODS

We retrospectively analyzed a cohort of 544 patients affected by metastatic breast cancer. Variation in ER, PR, Ki67 and HER2 expression between primary site and recurrence was tested through the McNemar test.

RESULTS

A significant variation was observed in respect to ER, PR and Ki67 status (12.65%, p = 0.0072; 49.71%, p < 0.0001; 35%, p < 0.0001, respectively). Among patients with ER or PR discordance, the driver of therapeutic decisions was the ER status. Moreover, we observed a therapy-related reduction of ER in taxanes or aromatase inhibitors-exposed patients (odds ratio: 3.59; 95% CI: 1.66-7.77; p = 0.001 and odds ratio: 2.07; 95% CI: 0.96-4.44; p = 0.06, respectively).

CONCLUSION

Biopsy of metastatic lesions may influence the decision-making process translating into better outcome.

A retrospective study of trifluridine/tipiracil in pretreated metastatic colorectal cancer patients in clinical practice

Aim: RECOURSE trial has shown a benefit for trifluridine/tipiracil (also known as TAS-102) over placebo in chemorefractory metastatic colorectal cancer (mCRC) patients. We evaluated efficacy and safety of patients treated with trifluridine/tipiracil in compassionate use. Patients & methods: RETROTAS is a retrospective study designed to evaluate efficacy and safety of trifluridine/tipiracil in mCRC patients previously exposed or not a candidate to all available drugs. Results: A total of 85 mCRC patients were included. Our data showed that 37.6% of patients achieved disease control. Median progression-free survival was 2.3 months; at 16 months follow-up, median overall survival was 9.2 months. Conclusion: This real-life experience confirms the safety and efficacy of trifluridine/tipiracil, resulting as a valid option in chemorefractory mCRC treatment scenario.

Biomarkers of Primary Resistance to Trastuzumab in HER2-Positive Metastatic Gastric Cancer Patients: the AMNESIA Case-Control Study

Purpose: Refining the selection of HER2-positive metastatic gastric cancer patient candidates for trastuzumab is a challenge of precision oncology. Preclinical studies have suggested several genomic mechanisms of primary resistance, leading to activation of tyrosine kinase receptors other than HER2 or downstream signaling pathways.Experimental Design: We carried out this multicenter, prospective, case-control study to demonstrate the negative predictive impact of a panel of candidate genomic alterations (AMNESIA panel), including EGFR/MET/KRAS/PI3K/PTEN mutations and EGFR/MET/KRAS amplifications. Hypothesizing a prevalence of candidate alterations of 30% and 0% in resistant and sensitive HER2-positive patients, respectively, 20 patients per group were needed.Results: AMNESIA panel alterations were significantly more frequent in resistant (11 of 20, 55%) as compared with sensitive (0% of 17) patients (P < 0.001), and in HER2 IHC 2⁺ (7 of 13, 53.8%) than 3⁺ (4 of 24, 16.7%) tumors (P = 0.028). Patients with tumors bearing no candidate alterations had a significantly longer median progression-free [5.2 vs. 2.6 months; HR, 0.34; 95% confidence interval (CI), 0.07-0.48; P = 0.001] and overall survival (16.1 vs. 7.6 months; HR, 0.38; 95% CI, 0.09-0.75; P = 0.015). The predictive accuracy of the AMNESIA panel and HER2 IHC was 76% and 65%, respectively. The predictive accuracy of the combined evaluation of the AMNESIA panel and HER2 IHC was 84%.Conclusions: Our panel of candidate genomic alterations may be clinically useful to predict primary resistance to trastuzumab in patients with HER2-positive metastatic gastric cancer and should be further validated with the aim of molecularly stratifying HER2-addicted cancers for the development of novel treatment strategies. Clin Cancer Res; 24(5); 1082-9. ©2017 AACR.

Sarcopenia in gastric cancer: when the loss costs too much

Sarcopenia is a complex syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength. Malignancy is a major determinant of sarcopenia, and gastric cancer (GC) is among the most common causes of this phenomenon. As sarcopenia is a well-recognized poor prognostic feature in GC and has been associated with worse tolerance of surgical and medical treatments, members of the multidisciplinary team should be aware of the clinical relevance, pathogenic mechanisms, and potential treatments for this syndrome. The importance of sarcopenia is often underestimated in everyday practice and clinical trials, particularly among elderly or fragile patients. As treatment options are improving in all disease stages, deeper knowledge and greater attention to the metabolic balance in GC patients could further increase the benefit of novel therapeutic strategies and dramatically impact on quality of life. In this review, we describe the role of sarcopenia in different phases of GC progression. Our aim is to provide oncologists and surgeons dealing with GC patients with a useful tool for comprehensive assessment and timely management of this potentially life-threatening condition.

Molecular classifications of gastric cancers: Novel insights and possible future applications

Despite some notable advances in the systemic management of gastric cancer (GC), the prognosis of patients with advanced disease remains overall poor and their chance of cure is anecdotic. In a molecularly selected population, a median overall survival of 13.8 mo has been reached with the use of human epidermal growth factor 2 (HER2) inhibitors in combination with chemotherapy, which has soon after become the standard of care for patients with HER2-overexpressing GC. Moreover, oncologists have recognized the clinical utility of conceiving cancers as a collection of different molecularly-driven entities rather than a single disease. Several molecular drivers have been identified as having crucial roles in other tumors and new molecular classifications have been recently proposed for gastric cancer as well. Not only these classifications allow the identification of different tumor subtypes with unique features, but also they serve as springboard for the development of different therapeutic strategies. Hopefully, the application of standard systemic chemotherapy, specific targeted agents, immunotherapy or even surgery in specific cancer subgroups will help maximizing treatment outcomes and will avoid treating patients with minimal chance to respond, therefore diluting the average benefit. In this review, we aim at elucidating the aspects of GC molecular subtypes, and the possible future applications of such molecular analyses.

Immunotherapy for colorectal cancer: where are we heading?

INTRODUCTION

In the last few years, significant advances in molecular biology have provided new therapeutic options for colorectal cancer (CRC). The development of new drugs that target the immune response to cancer cells seems very promising and has already been established for other tumor types. In particular, the use of immune checkpoint inhibitors seems to be an encouraging immunotherapeutic strategy. Areas covered: In this review, the authors provide an update of the current evidence related to this topic, though most immunotherapies are still in early-phase clinical trials for CRC. To understand the key role of immunotherapy in CRC, the authors discuss the delicate balance between immune-stimulating and immune-suppressive networks that occur in the tumor microenvironment. Expert opinion: Modulation of the immune system through checkpoint inhibition is an emerging approach in CRC therapy. Nevertheless, selection criteria that could enable the identification of patients who may benefit from these agents are necessary. Furthermore, potential prognostic and predictive immune biomarkers based on immune and molecular classifications have been proposed. As expected, additional studies are required to develop biomarkers, effective therapeutic strategies and novel combinations to overcome immune escape resistance and enhance effector response.

Immunotherapy for gastric cancers: emerging role and future perspectives

INTRODUCTION

The broad use of immunotherapy is revolutionizing the treatment paradigms of many solid tumors. Although chemotherapy remains the treatment backbone for advanced gastric cancer, improvements in its molecular characterization and progresses in understanding its underpinning biology have supported clinical development of novel immunotherapies. However, the results of recent trials testing these new agents raise the question on how to identify the patients that could greatly benefit. Areas covered: This article summarizes the current understanding on the biology and the mechanisms underlying different clinical features of gastric cancers. Particularly, after a comprehensive literature search, we speculate whether specific molecular subsets of patients could derive more benefit from immunotherapy. Expert commentary: Most cancers may evade the immune response, which is normally regulated by a delicate balance between activating and inhibitory signals. For example, both CTLA-4 and PD-1, once linked to PD-L1/2, may inhibit T-cell signaling. The use of agent to harness the power of the immune system appears to be the ultimate frontier in gastric cancer treatment. While anti-CTLA-4 antibodies are minimally active, there is growing evidence for the efficacy of PD1/-L1 inhibitors. The search of predictive factors for immunotherapy will provide key hints towards the optimal use of these agents.

HER-2 inhibition in gastric and colorectal cancers: tangible achievements, novel acquisitions and future perspectives

HER-2 (ErbB-2, c-erbB2 or Her2/neu), a member of the HER-family, is directly involved in the pathogenesis and progression of several human cancers; as such, it is also often considered as a poor prognostic factor. Following the revolutionary impact of anti-HER-2 therapy in breast cancer patients, the role of HER-2 and its blockade has also been extensively evaluated in other tumor types, including gastric and colorectal adenocarcinoma. The aims of this review are to recall the important results achieved with the use of HER-2 inhibitors in both gastric and colorectal cancer, and to discuss on the updates available on the role of HER-2 as prognostic and predictive factor in these malignancies.

HER2 loss in HER2-positive gastric or gastroesophageal cancer after trastuzumab therapy: Implication for further clinical research

Mechanisms of acquired resistance to trastuzumab-based treatment in gastric cancer are largely unknown. In this study, we analyzed 22 pairs of tumor samples taken at baseline and post-progression in patients receiving chemotherapy and trastuzumab for advanced HER2-positive [immunohistochemistry (IHC) 3+ or 2+ with in-situ hybridization (ISH) amplification] gastric or gastroesophageal cancers. Strict clinical criteria for defining acquired trastuzumab resistance were adopted. Loss of HER2 positivity and loss of HER2 over-expression were defined as post-trastuzumab IHC score <3+ and absence of ISH amplification, and IHC "downscoring" from 2+/3+ to 0/1+, respectively. HER2 IHC was always performed, while ISH was missing in 3 post-progression samples. Patients with initial HER2 IHC score 3+ and 2+ were 14 (64%) and 8 (36%), respectively. Loss of HER2 positivity and HER2 over-expression was observed in 32 and 32% samples, respectively. The chance of HER2 loss was not associated with any of the baseline clinicopathological variables. The only exception was in patients with initial IHC score 2+ versus 3+, for both endpoints of HER2 positivity (80 vs. 14%; p = 0.008) and HER2 over-expression (63 vs. 14%; p = 0.025). As already shown in breast cancer, loss of HER2 may be observed also in gastric cancers patients treated with trastuzumab-based chemotherapy in the clinical practice. This phenomenon may be one of the biological reasons explaining the failure of anti-HER2 second-line strategies in initially HER2-positive disease.