Efficacy of Regorafenib and Trifluridine/Tipiracil According to Extended RAS Evaluation in Advanced Metastatic Colorectal Cancer Patients: A Multicenter Retrospective Analysis

BACKGROUND

There are few molecular markers driving treatment selection in later lines of treatment for advanced colorectal cancer patients. The vast majority of patients who progress after first- and second-line therapy undergo chemotherapy regardless of molecular data.

OBJECTIVE

We aimed to assess the prognostic and predictive effects of specific RAS mutations on overall survival of patients receiving regorafenib (rego), trifluridine/tipiracil (TFD/TPI), or both.

PATIENTS AND METHODS

This was a retrospective observational study based on data from a previous study of our research network, involving nine Italian institutions over a 10-year timeframe (2012-2022). Extended RAS analysis, involving KRAS exon 2-4 and NRAS exon 2-4, and BRAF were the main criteria for inclusion in this retrospective evaluation. Patients with BRAF mutation were excluded. Patients were classified according to treatment (rego- or TFD/TPI-treated) and RAS mutational status (wild-type [WT], KRAS codon 12 mutations, KRAS codon 13 mutations, KRAS rare mutations and NRAS mutations, KRAS G12C mutation and KRAS G12D mutation).

RESULTS

Overall, 582 patients were included in the present analysis. Overall survival did not significantly differ in rego-treated patients according to RAS extended analysis, although a trend toward a better median survival in patients carrying G12D mutation (12.0 months), Codon 13 mutation (8.0 months), and Codon 12 mutation (7.0 months) has been observed, when compared with WT patients (6.0 months). Overall survival did not significantly differ in TFD/TPI-treated patients according to RAS extended analysis, although a trend toward a better median survival in WT patients had been observed (9.0 months) in comparison with the entire population (7.0 months). Patients receiving both drugs displayed a longer survival when compared with the population of patients receiving rego alone (p = 0.005) as well as the population receiving TFD/TPI alone (p < 0.001), suggesting a group enriched for favorable prognostic factors. However, when each group was analyzed separately, the addition of TFD/TPI therapy to the rego-treated group improved survival only in all-RAS WT patients (p = 0.003). Differently, the addition of rego therapy to TFD/TPI-treated patients significantly improved OS in the Codon 12 group (p = 0.0004), G12D group (p = 0.003), and the rare mutations group (p = 0.02), in addition to all-RAS WT patients (p = 0.002). The rego-TFD/TPI sequence, compared with the reverse sequence, significantly improved OS only in the KRAS codon 12 group (p = 0.003).

CONCLUSIONS

Our data demonstrate that RAS mutations do not affect outcome in rego-treated patients as well as TFD/TPI-treated patients. Nevertheless, a trend toward a higher efficacy of rego in RAS-mutated (in particular codon 12, rare RAS mutations, and G12D) patients has been recorded. The rego-TFD/TPI sequence seems to be superior to the reverse sequence in patients carrying an RAS codon 12 mutation, although the impact of other factors as disease burden or performance status cannot be excluded.

Hug sign in intraprocedural cone-beam-CT to predict short-term response to combined treatment of hepatocellular carcinoma

OBJECTIVES

Combined treatment of ablation and chemoembolization for hepatocellular carcinoma represents a promising therapy to increase treatment efficacy and improve patient survival. The "hug sign" is a recently introduced radiological sign consisting in deposition of beads/contrast agent during transarterial chemoembolization in the hyperemic area surrounding the post-ablation volume, seen during intraprocedural unenhanced cone-beam CT, that may indicate intraprocedural success. Aim of our retrospective study was to analyze the usefulness of the "hug sign" at the intraprocedural unenhanced cone-beam CT as an early predictor of response to combined treatment, based on the hug sign angle.

MATERIALS AND METHODS

Between January 2017 and September 2021 all patients with hepatocellular carcinoma which underwent a combined treatment of thermal ablation followed by chemoembolization were enrolled. All treated patients underwent immediate post-procedural unenhanced cone-beam CT to evaluate the deposition of contrast agent, lipiodol or radiopaque beads and to assess the percentage of coverage of the ablated area with the contrast agent (hug sign angle). Patients with missing pre-procedural, intra-procedural and/or post-procedural data/imaging, or with poor-quality post-procedural cone-beam CT images were excluded.

RESULTS

128 patients (mean age, 69.3 years ± 1.1 [standard deviation]; 87 men) were evaluated. Our study evidenced that 84.4% (81/85) of patients with a hug sign angle of 360° had no residual tumor at the first 1-/3-months follow-up examination. A hug sign angle of 360° also showed to be an independent protective factor against residual tumor at multivariate analysis.

CONCLUSION

Unenhanced cone-beam CT performed at the end of a combined treatment with ablation plus chemoembolization can effectively predict an early treatment response on radiological images, when a hug sign angle of 360° was detected.

Focus on RAS Codon 61 Mutations in Metastatic Colorectal Cancer: A Retrospective Analysis

RAS mutations involving codon 61 are rare in metastatic colorectal cancer (mCRC), accounting for only 1-4%, but they have recently been identified with high frequency in the circulating tumor DNA (ctDNA) of patients with secondary resistance to anti-EGFRs. This retrospective monocentric study aimed to investigate the clinical phenotype and prognostic performance of codon 61 RAS-mutated mCRC. Fifty patients with codon 61 RAS-mutated mCRC treated at our institution between January 2013 and December 2021 were enrolled. Additional datasets of codon 61 RAS wild-type mCRCs (648 patients) were used as comparators. The endpoint for prognostic assessment was overall survival (OS). Metastatic involvement of the peritoneum or ovary was significantly more frequent in codon 61 RAS-mutated mCRC compared to codon 61 RAS wild-type (54 vs. 28.5%), non-codon 61 RAS-mutated (35.6%), BRAF V600E-mutated (25%), and RAS/BRAF wild-type (20.5%) cohorts. At a median follow up of 96.2 months, the median OS for codon 61 RAS-mutated patients was significantly shorter compared to RAS/BRAF wild-type (26.9 vs. 36.0 months, HR 0.56) patients, while no significant difference was observed compared to non-codon 61 RAS-mutated and BRAF V600E-mutated patients. We showed a negative prognostic impact and a statistically significant correlation between codon 61 RAS mutations and metastatic involvement of the peritoneum and ovary.

Retrospective Correlation between First Drug Treatment Duration and Survival Outcomes in Sequential Treatment with Regorafenib and Trifluridine/Tipiracil in Refractory Metastatic Colorectal Cancer: A Real-World Subgroup Analysis

Background: Patients with refractory metastatic colorectal cancer (mCRC) rarely receive third-line or further treatment. In this context, regorafenib (R) and trifluridine/tipiracil (T) are two important novel therapeutic choices with statistically significant increases in overall survival (OS), progression-free survival (PFS), and disease control, with different toxicity profiles. This study is a subgroup analysis of our larger retrospective study, already published, whose objective was to assess the outcomes of patients when R and T were given sequentially. Patients and Methods: The study involved thirteen Italian cancer centers on a 10-year retrospective observation (2012-2022). In this subgroup analysis, we focused our attention on the correlation between the first drug treatment duration (<3 months, 3 to <6 months and ≥6 months) and survival outcomes in patients who had received the sequence regorafenib-to-trifluridine/tipiracil, or vice versa. Results: The initial study included 866 patients with mCRC who received sequential T/R, or R/T, or T or R alone. This analysis is focused on evaluating the impact of the duration of the first treatment in the sequence on clinical outcomes (OS, PFS) and includes 146 and 116 patients of the T/R and R/T sequences, respectively. Based on the duration of the first drug treatment, subgroups for the T/R sequence included 27 patients (18.4%) who received T for <3 months, 86 (58.9%) treated for 3 to <6 months, and 33 (22.6%) treated for ≥6 months; in the reverse sequence (R as the first drug), subgroups included 18 patients (15.5%) who received their first treatment for <3 months, 62 (53.4%) treated for 3 to <6 months, and 35 (31.0%) treated for ≥6 months. In patients who received their first drug treatment for a period of 3 to <6 months, the R/T sequence had a significantly longer median OS (13.7 vs. 10.8 months, p = 0.0069) and a longer median PFS (10.8 vs. 8.5 months, p = 0.0003) than the T/R group. There were no statistically significant differences between groups with first drug treatment durations of <3 months and ≥6 months. Conclusions: Our analysis seems to suggest that the administration of R for a period of 3 to <6 months before that of T can prolong both OS and PFS, as compared to the opposite sequence.

Maintenance strategies after anti-EGFR-based induction in metastatic colorectal cancer: A systematic review and bayesian network meta-analysis

BACKGROUND

In RAS wild type (wt) metastatic colorectal cancer (mCRC) maintenance therapy after induction with fluoropyrimidine (FP)-based cytotoxic therapy (CT) plus anti-EGFR agents is controversial.

METHODS

Phase II-III randomized trials were included. Maintenance strategies considered were: observation, anti-EGFR or FP monotherapy, FP + anti-EGFR, doublet CT + anti-EGFR.

RESULTS

Maintenance with FP + anti-EGFR (HR 0.56, 95% CrI 0.36-0.89) showed the greatest PFS benefit compared to observation, ranking first on SUCRA analysis (96.4%). Considering OS, doublet CT+ anti-EGFR, FP + anti-EGFR and anti-EGFR monotherapy yielded similar results. For PFS, FP + anti-EGFR confirmed to be valuable in BRAF wt patients and left sided tumors. In left sided tumors, the OS benefit of adding CT was limited. FP plus anti-EGFR showed a favourable safety profile compared to doublet CT + anti-EGFR.

CONCLUSIONS

FP + anti-EGFR can be considered a valuable maintenance option in RAS wt mCRC. EGFR monotherapy can be considered, especially in left-sided tumors.

A Convolutional Neural Network for Electrical Fault Recognition in Active Magnetic Bearing Systems

Active magnetic bearings are complex mechatronic systems that consist of mechanical, electrical, and software parts, unlike classical rolling bearings. Given the complexity of this type of system, fault detection is a critical process. This paper presents a new and easy way to detect faults based on the use of a fault dictionary and machine learning. The dictionary was built starting from fault signatures consisting of images obtained from the signals available in the system. Subsequently, a convolutional neural network was trained to recognize such fault signature images. The objective of this study was to develop a fault dictionary and a classifier to recognize the most frequent soft electrical faults that affect position sensors and actuators. The proposed method permits, in a computationally convenient way that can be implemented in real time, the determination of which component has failed and what kind of failure has occurred. Therefore, this fault identification system allows determining which countermeasure to adopt in order to enhance the reliability of the system. The performance of this method was assessed by means of a case study concerning a real turbomachine supported by two active magnetic bearings for the oil and gas field. Seventeen fault classes were considered, and the neural network fault classifier reached an accuracy of 93% on the test dataset.

Treatment Settings and Outcomes with Regorafenib and Trifluridine/Tipiracil at Third-Line Treatment and beyond in Metastatic Colorectal Cancer: A Real-World Multicenter Retrospective Study

BACKGROUND

Patients with refractory mCRC rarely undergo third-line or subsequent treatment. This strategy could negatively impact their survival. In this setting, regorafenib (R) and trifluridine/tipiracil (T) are two key new treatment options with statistically significant improvements in overall survival (OS), progression-free survival (PFS), and disease control with different tolerance profiles. This study aimed to retrospectively evaluate the efficacy and safety profiles of these agents in real-world practice.

MATERIALS AND METHODS

In 2012-2022, 866 patients diagnosed with mCRC who received sequential R and T (T/R, n = 146; R/T, n = 116]) or T (n = 325]) or R (n = 279) only were retrospectively recruited from 13 Italian cancer institutes.

RESULTS

The median OS is significantly longer in the R/T group (15.9 months) than in the T/R group (13.9 months) (p = 0.0194). The R/T sequence had a statistically significant advantage in the mPFS, which was 8.8 months with T/R vs. 11.2 months with R/T (p = 0.0005). We did not find significant differences in outcomes between groups receiving T or R only. A total of 582 grade 3/4 toxicities were recorded. The frequency of grade 3/4 hand-foot skin reactions was higher in the R/T sequence compared to the reverse sequence (37.3% vs. 7.4%) (p = 0.01), while grade 3/4 neutropenia was slightly lower in the R/T group than in the T/R group (66.2% vs. 78.2%) (p = 0.13). Toxicities in the non-sequential groups were similar and in line with previous studies.

CONCLUSIONS

The R/T sequence resulted in a significantly longer OS and PFS and improved disease control compared with the reverse sequence. R and T given not sequentially have similar impacts on survival. More data are needed to define the best sequence and to explore the efficacy of sequential (T/R or R/T) treatment combined with molecular-targeted drugs.

Sequential treatment with regorafenib and trifluridine/tipiracil in later-line refractory metastatic colorectal cancer: A real-world multicenter retrospective study

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Background: Regorafenib (R) and Trifluridine/tipiracil (T) have been shown to prolong survival for patients (pts) with refractory metastatic colorectal cancer (mCRC) but it's to date unclear which agent should be administered first. Our analysis aimed to compare the efficacy and safety profiles of these drugs sequentially administered in daily clinical practice. Methods: Clinical data of pts diagnosed with mCRC who received R and/or T between July 2012 and March 2022, were retrospectively collected from 12 institutes in Lazio Region. Overall survival (OS), progression-free survival (PFS), overall response rate (ORR), disease control rate (DCR), and adverse events (AEs) were compared between the two groups. Results: 781 pts were included. Of these, 270 (34.5%) received T alone, 278 (35.5%) R alone, 124 (15.8%) T followed by R, and 109 (13.9%) the reverse sequence. M/F = 452/329; median age was 68 (42-86); median duration of follow-up was 24.7 months (mos) (95%CI = 19.7-81.1). The prevalent ECOG PS was 1 (54%). We focused our attention on 233 pts who received R/T (N = 110, 14%) or T/R sequence (N = 123, 15.7%). ≥2 metastatic sites prevailed in both groups (83% T/R, 88% R/T; p = 0.45). Drug dose reductions due to grade 3/4 AEs were carried out in 81.8% of the R/T-treated pts (the R dose reduction to 120 mg and the T dose reduction to 30 mg/m2 were both the most prevalent in 28.8% of the cases) vs. 77.2% of the reverse sequence (R dose reduction to 120 mg was the most prevalent in 34.7% of the events) (p = 0.42). 143 pts (61.3%) experienced grade 3-4 toxicities (50.3% in R/T vs. 49.6% in T/R). The most common grade 3/4 AEs related to the R/T group were non-haematologic like hand-foot syndrome (21.6%) and fatigue (15.4%); on the other hand, these were haematologic: neutropenia (36.4%) and anemia (13%) (p = 0.28). Only 1 pt discontinued T in the T/R group. No therapy-related death was reported. The median PFS and OS of R/T were longer than the T/R sequence: 11 vs. 8,5 mos (HR = 0,62; 95%CI = 0,46-0,83; p = 0.0014) and 14,9 vs. 13 mos (HR = 0,70; 95%CI = 0,51-0,96; p = 0.0296), respectively. The ORR did not differ significantly showing slightly higher in the T/R sequence (4.8% vs. 2.2%; p = 0.45). The DCR was in favor of the R/T group (44.4% vs. 33.9%; p = 0.14). Conclusions: In our real-world context, PFS and OS were significantly longer in the R/T group. R and T used sequentially could extend survival and stabilize cancer growth without acting on tumor shrinkage. Safety profiles are in line with published data. Dose reductions were more frequent in the R/T group. We suggest that prospective clinical trials directly comparing R and T are needed.

Maintenance strategies after anti–EGFR-based induction in RAS wild-type (wt) metastatic colorectal cancer (mCRC): A systematic review and Bayesian network meta-analysis

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Background: In RAS wt mCRC the use of maintenance therapy after induction with fluoropyrimidine (FP)-based cytotoxic therapy (CT) plus anti-EGFR agents is controversial. Herein, we conducted a systematic review and network meta-analysis to compare different maintenance strategies. Methods: PubMed, CENTRAL, Embase and oncological meeting websites were screened to identify eligible studies. Phase II-III randomized trials which enrolled patients with previously untreated RAS wt mCRC, who switched to a maintenance strategy after an induction of CT combined with an anti-EGFR agent were included. Maintenance strategies considered were: observation, single agent anti-EGFR or FP, FP + anti-EGFR, doublet CT + anti-EGFR. Outcomes were progression-free survival (PFS), overall survival (OS) and safety (grade 3-4 adverse events). Subgroup analyses were performed in BRAF wt patients and left sided tumors. The meta-analysis was conducted using a random-effects model. A Markov Chain Monte Carlo simulation was used to estimate the posterior distributions. Strategies were ranked using the surface under the cumulative ranking (SUCRA) probabilities. Risk of bias was assessed with Cochrane Risk of Bias Tool. Results: Overall, 4207 records were screened and 10 trials were included in the analysis. Cumulative risk of bias was low-moderate. Maintenance therapy with FP + anti-EGFR (HR 0.56, 95% CrI 0.36-0.88) and doublet CT + anti-EGFR (HR 0.68, 95% CrI 0.46-1.01), showed the greatest PFS benefit compared to observation. On SUCRA analysis, FU + anti-EGFR had the highest likelihood of improving PFS (96.3%), compared to doublet CT + anti-EGFR (73.5%) or EGFR monotherapy (48.0%). In terms of OS, compared to observation, maintenance therapy with doublet CT + anti-EGFR (HR 0.51, 95% CrI 0.19-1.28), FU + anti-EGFR (HR 0.59, 95% CrI 0.19-1.68) or anti-EGFR monotherapy (HR 0.56, 95% CrI 0.24-1.34) yielded similar results. On SUCRA analysis probabilities were 78.3% with doublet CT + anti-EGFR, 64.5% with FP + anti-EGFR and 63.4% with anti-EGFR monotherapy. FP + anti-EGFR confirmed to be the best option in terms of PFS in BRAF wt patients (SUCRA: 96.3%) and left sided tumors (SUCRA: 89.6%). OS results in BRAF wt patients were consistent with the primary analysis. In left sided tumors, the OS benefit of adding CT seems limited compared to EGFR monotherapy. The addition of CT to anti-EGFR agents resulted in an increase of toxicity while FP monotherapy plus anti-EGFR showed a favourable safety profile compared to doublet CT + anti-EGFR. Conclusions: FP + anti-EGFR should be considered the best maintenance option in RAS wt mCRC in terms of PFS. Taking into account the similar OS performance of the different strategies, EGFR monotherapy could be considered, especially in left-sided tumors. Doublet CT + anti-EGFR, despite being effective, is limited by toxicities.

Efficacy of third-line anti-EGFR-based treatment versus regorafenib or trifluridine/tipiracil according to primary tumor site in RAS/BRAF wild-type metastatic colorectal cancer patients

Background

Right- (R) and left-sided (L) metastatic colorectal cancer (mCRC) exhibit different clinical and molecular features. Several retrospective analyses showed that survival benefit of anti-EGFR-based therapy is limited to RAS/BRAF wt L-sided mCRC patients. Few data are available about third-line anti-EGFR efficacy according to primary tumor site.

Methods

RAS/BRAF wt patients mCRC treated with third-line anti-EGFR-based therapy versus regorafenib or trifluridine/tipiracil (R/T) were retrospectively collected. The objective of the analysis was to compare treatment efficacy according to tumor site. The primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS), response rate (RR) and toxicity.

Results

A total of 76 RAS/BRAF wt mCRC patients, treated with third-line anti-EGFR-based therapy or R/T, were enrolled. Of those, 19 (25%) patients had a R-sided tumor (9 patients received anti-EGFR treatment and 10 patients R/T) and 57 (75%) patients had a L-sided tumor (30 patients received anti-EGFR treatment and 27 patients R/T). A significant PFS [7.2 vs 3.6 months, HR 0.43 (95% CI 0.2-0.76), p= 0.004] and OS benefit [14.9 vs 10.9 months, HR 0.52 (95% CI 0.28-0.98), p= 0.045] in favor of anti-EGFR therapy vs R/T was observed in the L-sided tumor group. No difference in PFS and OS was observed in the R-sided tumor group. A significant interaction according to primary tumor site and third-line regimen was observed for PFS (p= 0.05). RR was significantly higher in L-sided patients treated with anti-EGFR vs R/T (43% vs. 0%; p <0.0001), no difference was observed in R-sided patients. At the multivariate analysis, third-line regimen was independently associated with PFS in L-sided patients.

Conclusions

Our results demonstrated a different benefit from third-line anti-EGFR-based therapy according to primary tumor site, confirming the role of L-sided tumor in predicting benefit from third-line anti-EGFR vs R/T. At the same time, no difference was observed in R-sided tumor.

Safety and Efficacy of a First-Line Chemotherapy Tailored by G8 Score in Elderly Metastatic or Locally Advanced Gastric and Gastro-Esophageal Cancer Patients: A Real-World Analysis

Introduction: Gastric (GC) and gastro-esophageal cancer (GEC) are common neoplasms in the elderly. However, in clinical practice, the correct strategy for elderly patients who might benefit from chemotherapy (CT) is unknown. Prospective data are still poor. In this context, we performed a retrospective analysis of GC patients aged ≥75 years and treated at our institutions. Material and Methods: We retrospectively analyzed 90 patients with confirmed metastatic GC or GEC, treated with an upfront CT. Inclusion criteria were patients aged ≥75 years, PS 0−2, normal bone marrow/liver/renal function and no major comorbidities. All patients received a G8 score, and some patients with G8 ≤14 received a comprehensive geriatric assessment (CGA). The primary goal was to perform a safety evaluation based on the incidence of adverse events (AE), and the secondary goal was to determine the efficacy (PFS and OS). The chi-square test and the Kaplan−Meier method were used to estimate the outcomes. The statistical significance level was set at p < 0.05. Results: Toxicity rates were quite low: G1/G2 (51.1%) and G3/G4 (25.5%). No toxic deaths were reported. The median PFS was 6.21 months and the median OS 11 months. The G8 score and PS ECOG significantly influenced both PFS and OS. A statistically significant correlation among G8, weight loss, hypoalbuminemia and risk of G3/G4 adverse events was also found. Conclusion: Our research on selected elderly patients did not detect broad differences of efficacy and tolerability compared to a young population. Our study, although retrospective and small-sized, showed that G8 score might be an accurate tool to identify elderly GC/GEC patients who could be safely treated with CT, further recognizing patients who could receive a doublet CT and who may require a single agent chemotherapy or a baseline dose reduction.

The impact of the multidisciplinary team (MDT) in the management of colorectal cancer (CRC)

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Background: The management of CRC is complex, particularly in metastatic disease, where it is crucial the definition of disease burden, the assessment of radiological response and the identification of the right timing for potential radical surgery or loco-regional treatments. A correct CRC evaluation and the subsequent choice of the most appropriate treatment strategy, need, therefore, a MDT involving surgeons, oncologists, radiologists, radiation oncologists, endoscopists, gastroenterologists and pathologists. Based on such considerations, we investigated the impact of the MDT meeting in the management of CRC at our Institution. Methods: We retrospectively evaluated all the cases discussed at our MDT meeting between September 2019 and September 2021. We collected data, both pre- and post-MDT meeting, regarding radiology evaluation (disease control vs progression), surgical assessment (yes vs no) and radiotherapy evaluation (yes vs no). Primary endpoint was the overall rate of discrepancy in evaluation between pre- and post-MDT meeting. Results: Between September 2019 and September 2021, 696 cases were presented at our MDT meeting. The median age was 65 years (24-86), 391 (56%) patients were male and 553 (79%) patients had metastatic disease at diagnosis. After MDT meeting, a total of 214 decisions were modified, for an overall discrepancy rate of 31%. In particular, among 377 cases discussed for radiology evaluation, 110 decisions (29%) were modified after a central imaging review: 80 cases initially evaluated as progressed disease before MDT meeting were defined stable after MDT meeting, for a discrepancy rate of 73%. Regarding the 246 cases discussed for surgical assessment on primary tumor and/or metastatic sites, treatment strategy changed in 86 cases (35%). More specifically, 16 cases (19%), evaluated unresectable before MDT meeting, were then considered resectable after MDT meeting. Finally, among the 71 cases discussed for radiotherapy evaluation, treatment strategy changed in 18 cases (25%). Conclusions: Our analysis demonstrates a significant rate of discrepancy in radiology and/or surgical evaluation between pre- and post-MDT meeting. Our results show that a MDT allows a considerable modification in CRC management, maximizing the treatment strategy, in particular avoiding unnecessary changes in therapy and allowing surgery where possible.

Toward next-generation primate neuroscience: A collaboration-based strategic plan for integrative neuroimaging

Open science initiatives are creating opportunities to increase research coordination and impact in nonhuman primate (NHP) imaging. The PRIMatE Data and Resource Exchange community recently developed a collaboration-based strategic plan to advance NHP imaging as an integrative approach for multiscale neuroscience.

Mutational status of plasma exosomal KRAS predicts outcome in patients with metastatic colorectal cancer

Liquid biopsy has become a useful alternative in metastatic colorectal cancer (mCRC) patients when tissue biopsy of metastatic sites is not feasible. In this study we aimed to investigate the clinical utility of circulating exosomes DNA in the management of mCRC patients. Exosomes level and KRAS mutational status in exosomal DNA was assesed in 70 mCRC patients and 29 CRC primary tumor and were analysed at different disease steps evaluating serial blood samples (240 blood samples). There was a significant correlation between the extension of disease and exosomes level and the resection of primary localized tumor was correlated with a decrease of KRAS G12V/ D copies and fractional abundance in metastatic disease. CEA expression and liver metastasis correlated with a higher number of KRAS G12V/D copies/ml and a higher fractional abundance; in the subgroup of mCRC patients eligible for surgery, the size of tumor and the radiological response were related to exosomes level but only the size was related to the number of KRAS WT copies; both KRAS wild-type and mutated levels were identified as a prognostic factor related to OS. Finally, we found that 91% of mutated mCRC patients became wild type after the first line chemotherapy but this status reverted in mutated one at progression in 80% of cases. In a prospective cohort of mCRC patients, we show how longitudinal monitoring using exosome-based liquid biopsy provides clinical information relevant to therapeutic stratification.

Measuring Viscosity Using the Hysteresis of the Non-Linear Response of a Self-Excited Cantilever

A self-oscillating microcantilever in a feedback loop comprised of a gain, a saturator, and an adjustable phase-shifter is used to measure the viscosity of Newtonian fluids. Shifting the signal of the loop with the adjustable phase-shifter causes sudden jumps in the oscillation frequency of the cantilever. The exact position of these jumps depends on whether the shift imposed by the phase-shifter is increasing or decreasing and, therefore, the self-excited cantilever exhibits a hysteretic non-linear response. This response was studied and the system modeled by a delay differential equation of motion where frequency-dependent added mass and damping terms accounted for the density and the viscosity of the medium. Experimental data were obtained for solutions with different concentrations of glycerol in water and used to validate the model. Two distinct sensing modalities were proposed for this system: the sweeping mode, where the width of the observed hysteresis depends on the viscosity of the medium, and the threshold mode, where a sudden jump of the oscillation frequency is triggered by an arbitrarily small change in the viscosity of the medium.

The role of site of metastatic resection (MR) in metastatic colorectal cancer (mCRC) patients (PTS): A mono-institutional cohort study

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Background: Approximately 50%-60% of CRC pts develop metastases, usually to liver and lung. When feasible, MR is the only potentially curative option in the multimodal management of mCRC pts. Few studies have compared survival outcomes based on different surgical sites with contrasting data. Hence, we retrospectively analyzed mCRC pts, underwent radical lung and/or liver resection at our Institution, investigating the impact of resection site on overall survival (OS). Methods: mCRC pts underwent radical liver (group 1), lung (group 2) or liver and lung (group 3) resection were included. The following variables were collected: age ( > vs ≤ 65 years); gender (male vs female); primary tumor site (right vs left); synchronous vs metachronous; RAS/BRAF status; number (N) of MR (1, 2 or ≥3); chemotherapy treatment (No treatment vs Post-operative vs Peri-operative/pre-operative treatment) and chemotherapy regimen (5FU monotherapy, Oxaliplatin-based, Irinotecan-based regimen, FOLFOXIRI, Bevacizumab, Anti-EGFR). The association of MR site and OS was evaluated. Univariate and multivariate analyses for OS were performed. Results: A total of 191 mCRC pts underwent radical MR were included in the analysis: 112 (59%) pts in group 1, 38 pts (20 %) in group 2, 41 pts (21 %) in group 3. 145 (76%) pts had a left-sided tumor and 46 (24%) a right-sided tumor. Out of 156 evaluable pts, 73 (47%) pts harbored a RAS mutation, while out of 136 evaluable pts, 4 (3%) pts had a BRAF mutation. Regarding the N of MR, 125 pts (65%) underwent 1 radical MR, 43 (23%) pts 2 MR and 23 (12%) ≥3 MR. In the overall population, median OS was 77.2 months. According to MR site, median OS was 59.4, not reached (NR) and 99.1 months, in group 1, 2 and 3, respectively (p = 0.075). At the multivariate analysis no significant association with OS was shown for MR site, while the N of MR and RAS status were indipendently associated with OS. Median OS was 58.5, 97.7 months and NR in pts underwent 1, 2 and ≥3 MR, respectively (p = 0.02). Median OS was 58.5 and 83.1 months in RAS mutated and RAS wild-type pts, respectively (p = 0.12). Conclusions: Despite the limited number of pts and the retrospective nature of our study, these results confirmed that surgery represents the only option with curative intent for mCRC pts, independently of metastatic site (liver vs lung vs liver and lung). Based on our analysis, a higher number of MR is associated to a better outcome, and this could be explained with an accurate selection of patients that could benefit from multiple radical resections. Thus, a multidisciplinary approach is essential for the management of mCRC pts and surgery should be evaluated case by case and always performed when possible, even several times, independently of site of MR.

Endovascular repair and open repair surgery of thoraco-abdominal aortic aneurysms cause drastically different types of spinal cord injury

Both endovascular repair (EVR) and open repair (OR) surgery of thoraco-abdominal aortic aneurysms cause spinal cord (SC) injury that can lead to paraparesis or paraplegia. It has been assumed that mechanisms responsible for SC damage after EVR are similar to those after OR. This pilot study compared the pathophysiology of SC injury after EVR versus OR using a newly developed EVR dog model. An increasing number of stents similar to those used in patients were inserted in the aorta of three dogs to ensure thoracic or thoracic plus lumbar coverage. The aorta of OR dogs was cross-clamped for 45 min. Behavior assessment demonstrated unique patterns of proprioceptive ataxia and evolving paraparesis in EVR versus irreversible paraplegia in OR. MRI showed posterior signal in lumbar SC after EVR versus central cord edema after OR. Histopathology showed white matter edema in L3-L5 localized to the dorsal column medial lemniscus area associated with loss of myelin basic protein but not neurons after EVR, versus massive neuronal loss in the gray matter in L3-L5 after OR. Metabolome analysis demonstrates a distinctive chemical fingerprint of cellular processes in both interventions. Our results call for the development of new therapeutics tailored to these distinct pathophysiologic findings.

Elasticity spectra as a tool to investigate actin cortex mechanics

Background

The mechanical properties of single living cells have proven to be a powerful marker of the cell physiological state. The use of nanoindentation-based single cell force spectroscopy provided a wealth of information on the elasticity of cells, which is still largely to be exploited. The simplest model to describe cell mechanics is to treat them as a homogeneous elastic material and describe it in terms of the Young’s modulus. Beside its simplicity, this approach proved to be extremely informative, allowing to assess the potential of this physical indicator towards high throughput phenotyping in diagnostic and prognostic applications.

Results

Here we propose an extension of this analysis to explicitly account for the properties of the actin cortex. We present a method, the Elasticity Spectra, to calculate the apparent stiffness of the cell as a function of the indentation depth and we suggest a simple phenomenological approach to measure the thickness and stiffness of the actin cortex, in addition to the standard Young’s modulus.

Conclusions

The Elasticity Spectra approach is tested and validated on a set of cells treated with cytoskeleton-affecting drugs, showing the potential to extend the current representation of cell mechanics, without introducing a detailed and complex description of the intracellular structure.

The impact of multidisciplinary team management on outcome of hepatic resection in liver-limited colorectal metastases

Hepatic resection is the gold standard treatment for patients affected by liver-limited colorectal metastases. Reports addressing the impact of multidisciplinary team (MDT) evaluation on survival are controversial. The aim of this study was to evaluate the benefit of MDT management in these patients in our Institution experience. The objective of the analysis was to compare survivals of patients managed within our MDT (MDT cohort) to those of patients referred to surgery from other hospitals without MDT discussion (non-MDT cohort). Of the 523 patients, 229 were included in the MDT cohort and 294 in the non-MDT cohort. No difference between the two groups was found in terms of median overall survival (52.5 vs 53.6 months; HR 1.13; 95% CI, 0.88-1.45; p = 0.344). In the MDT cohort there was a higher number of metastases (4.5 vs 2.7; p < 0.0001). The median duration of chemotherapy was lower in MDT patients (8 vs 10 cycles; p < 0.001). Post-operative morbidity was lower in the MDT cohort (6.2 vs 21.5%; p < 0.001). One hundred and ninety-seven patients in each group were matched by propensity score and no significant difference was observed between the two groups in terms of OS and DFS. Our study does not demonstrate a survival benefit from MDT management, but it allows surgery to patients with a more advanced disease. MDT assessment reduces the median duration of chemotherapy and post-operative morbidities.

Outcomes of cementless fixation in medial unicompartmental knee arthroplasty: review of recent literature

INTRODUCTION

Medial unicompartmental knee arthroplasty (UKA) is considered the most effective treatment for anteromedial knee osteoarthritis. Cementless fixation of UKA was developed to reduce aseptic loosening. We performed a review of the recent literature to assess the latest outcomes of cementless UKA.

METHODS

A review of English literature was performed on Medline through Pubmed. Retrospective or prospective studies with at least 2 years of follow-up (FU) and at least 20 patients were included. The PRISMA 2009 flowchart and checklist were considered to edit the review. Survival rate, revision rate, time for revision, incidence of radiolucent lines and reasons for revision (such as aseptic loosening, osteoarthritis progression, bearing dislocation or periprosthetic fracture) were extrapolated from the papers.

RESULTS

Nineteen articles were included in the review, only 2 with a level of evidence of I. A total of 3432 UKA with a FU range of 24-132 months were analyzed. The studies showed good clinical and functional outcomes. In 12 studies, survival rate were more than 90%. Revision rate for aseptic loosening were lower than 2% for 15 studies.

CONCLUSION

Cementless UKA represents a surgical option allowing low revision rate. Further high-quality long-term studies would better clarify complications, clinical and radiological results of this promising fixation method.

Baseline radiomics features (RF) in metastatic colorectal cancer (mCRC): Correlation with m site and clinical-pathological characteristics

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Background: R is an emerging field of research based on the extraction of a large amount of F from biomedical images and on computed analysis algorithms of tumour architecture. Few data regarding mCRC are available, in particular no correlation of baseline RF both with m sites and clinical-pathological characteristics was so far investigated. Methods: Baseline chest-abdomen CT scans of mCRC patients (pts) were retrospectively analysed. RF were extracted from Regions of Interest (ROI) delineated on CT scan from each m sites, including primary tumor, when on site. The association of specific F and disease site (liver, lung, nodes, peritoneum and on-site primary tumor) was investigated. Sites similarity was assessed with Principal Component Analysis, an unsupervised learning technique to identify patterns and clusters. Then RFs were tested individually for correlation with clinical-pathological covariates of interest (gender, CEA level, synchronous disease, RAS/BRAF status, mucinous histology, grading, number of m site, primary tumor site). Wilcoxon-Mann-Whitney test was used for this purpose (significance level set at 0.05). Results: After RF extraction from the different ROIs, the dataset was composed of 433 observations of 236 variables. Observations referred to the number (N) of pts = 89 and the N of ROIs = 18. RF classes were divided in statistical F (grey-level histogram) (N of F = 10); morphological F (N = 14); texture F GLCM (grey level co-occurrence matrix) (N = 100); texture F GLRLM (grey level run length matrix) (N = 66); texture F GLSZM (grey level size zone matrix) (N = 32). Regarding the association of RF with m sites, an homogenous distribution with liver, nodes, peritoneum and primary tumor was detected, while lung metastases showed a different pattern for all the RF classes. A significant correlation of specific RF with clinical-pathologic characteristics was shown, in particular with gender, CEA level, synchronous disease, mucinous histology, RAS/BRAF status. Conclusions: Despite its retrospective nature and the limited number of pts, this is the first experience demonstrating I) a different pattern of RF for lung m versus an homogeneous RF distribution for the other m sites; and II) a significant association of specific RF with few clinical-pathologic characteristics. Our results, if confirmed in a prospective validation set, may represent an hypothesis generator regarding the different behaviour of lung metastases and a possible R signature able to identify different prognostic subgroups of pts.

The role of primary tumor (PT) site as prognostic factor after resection of colorectal (CRC) liver metastases (LM): A mono-institutional cohort study

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Background: Radical resection of LM is the only chance of cure for liver-only mCRC pts. Besides the evaluation of technical resectability, several factors must be taken into account for the evaluation of recurrence risk. Among them we should consider the Fong Risk Score and its modified version, including RAS/BRAF status (Brudvik’s score). Tumor sidedness is an important prognostic factor in CRC. The impact of PT site on the outcome of LM resection is still debated. Hence, we retrospectively analysed mCRC pts, underwent to radical LM resection at our Institution, investigating the impact of PT site on DFS and OS. Methods: Liver-only mCRC pts underwent to radical LM resection were included. The association of PT site with DFS and OS was evaluated. The following variables were collected: gender; age (≥ vs < 75 years ); ECOG PS; CEA baseline level; PT site; RAS and BRAF status; mucinous histology; grading (G1-2 vs G3); RECIST response during preoperative treatment; resected PT; synchronous vs metachronous; number of LM; bilobar vs unilobar LM; LM diameter ≥ 5 cm; R0 vs R1 resection. Univariate and multivariate analyses for DFS and OS were performed. Results: A total of 463 liver-only mCRC pts underwent to radical LM resection were included. Seventy (15%) pts had a right-sided (r-s) tumor and 393 (85%) pts a left-sided (l-s) tumor. R-s CRC pts more often had RAS/BRAF mutations in comparison to l-s tumors (76% vs 37%; p < 0.0001). Median DFS and OS was 13.1 and 41.6 months, respectively, in r-s CRC vs 16.0 (p = 0.65) and 62.2 months (p = 0.033), respectively, in l-s tumors. At the multivariate analysis no significant association with survival parameters was shown for tumor sidedness. At the multivariate analysis, R0 resection was independently associated both with better DFS and OS; RAS/BRAF wt CRC and resected PT were significantly associated with improved OS. Considering all wt CRC pts (N = 237), 14 (6%) pts had r-s tumor and 223 (94%) l-s tumor. No significant association of tumor sidedness with survival was shown (DFS r = 10.0 vs l = 16.0 months, p = 0.62; OS r = 40.3 vs l = 66.2 months, p = 0.12). Conclusions: Our results showed that a significant smaller proportion of r-s CRC underwent to radical LM resection, indirectly confirming its worse prognosis. Among radically resected pts, r-s CRC was associated to a shorter OS (significant) and DFS (not significant) compared to l-s CRC, but it was not confirmed at the multivariate analysis. We can conclude that right PT site should not be considered as a contraindication for radical LM surgery, when feasible.

Efficacy of third-line anti-EGFR-based treatment (tx) versus (vs) Regorafenib/TAS-102 (R/T) according to primary tumor site in RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC) patients (pts)

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Background: Right- (R) and left-sided (L) mCRCs exhibit different clinical and molecular features. Several retrospective analyses showed that the survival benefit of anti-EGFR-based tx is limited to RAS/BRAF wt L-sided mCRC pts, which a larger effect in the first-line setting. Few data are available concerning the anti-EGFR efficacy according to primary tumor site in third line. Methods: Pts affected by RAS/BRAF wt mCRC treated with third-line anti-EGFR-based tx or R/T were retrospectively collected. The objective of the analysis was to compare tx activity and efficacy according to tumor site. Primary endpoint was PFS; secondary endpoints were OS and RR. PFS and OS analyses were performed using Kaplan-Meier method, and survival curves were compared using the log-rank test. RR was evaluated according to RECIST criteria and it was compared in the two groups using Fisher’s exact test. Statistical significance was set at p = 0.05 for a bilateral test. Univariate and multivariate analyses for PFS and OS were performed. Results: A total of 76 RAS/BRAF wt mCRC pts, treated with third-line anti-EGFR-based tx or R/T, were enrolled. Of those, 19 (25%) pts had R-sided tumor (9 pts received anti-EGFR tx and 10 pts received R/T) and 57 (75%) pts had L-sided tumor (30 pts received anti-EGFR tx and 27 pts received R/T). As shown in the table, a significant PFS and OS benefit in favor of anti-EGFR tx vs R/T was observed in L-sided pts, while no difference both in PFS and OS was observed in R-sided pts. RR was significantly higher in L-sided pts treated with anti-EGFR vs R/T, no difference was shown in R-sided pts. At the multivariate analysis, tx regimen was indipendently associated with PFS in L-sided pts, but not in R-sided pts. Conclusions: Our study confirmed the results deriving from the retrospective analysis of the phase III study 20020408. Our results demonstrated a different benefit from third-line anti-EGFR tx according to primary tumor site, confirming the role of L-sided tumor in predicting benefit from third-line anti-EGFR vs R/T, while no difference was observed in R-sided tumors. [Table: see text]

Operator learning curve for transradial liver cancer embolization: implications for the initiation of a transradial access program

PURPOSE

We aimed to analyze transradial access (TRA) learning curve on patients undergoing hepatic chemoembolization, investigating the relationship between procedural volumes and various benchmarks of procedural success.

METHODS

We enrolled 60 consecutive patients who received two unilobar hepatic chemoembolizations within a 4-week interval performed by a single interventional radiologist, highly-trained in conventional transfemoral access (TFA) procedures, but without any previous practical experience in TRA procedures and with a preliminary 2-day theoretical training only. Consecutive patients were prospectively enrolled and analyzed in 3 groups: A (cases 1 to 20), B (cases 21 to 40), and C (cases 41 to 60). All patients underwent one hepatic chemoembolization using TRA and the other one using TFA in random order. All TFA procedures performed by the same operator in the same series of patients were considered as the control group. Primary endpoint was to analyze the relationship between TRA procedure operator experience and benchmarks of procedural success, to define the optimal procedural learning curve.

RESULTS

Technical success was obtained in all patients, with a crossover rate (radial to femoral access) of 0%. An association between incremental TRA operator experience (in terms of performed procedures) and decrease of preparation, puncture, fluoroscopy, and total examination times was observed. Similarly, inverse associations between incremental TRA operator experience and contrast medium (CM) volumes (P < 0.001) and radiation dose (RD) values (in terms of RAK - Reference Air Kerma) (P < 0.001) were also observed. Compared with TFA, CM volumes and RD values were significantly higher only in group A (cases 1-20). Procedure success remained high in all TRA groups and no significant association between TRA incremental experience and postprocedural outcomes was found. Higher postprocedural complaints at the access route and more limitations in performing basic activities were recorded after TFA vs. TRA (P < 0.001).

CONCLUSION

TRA catheterizations can be safely performed in patients treated for liver cancer embolization after a relatively short training in controlled conditions and with a better performance in comparison with TFA. Operator proficiency improves with greater TRA experience, with a threshold needed to overcome the learning curve represented by about 20 procedures.

Fusion rate and influence of surgery-related factors in lumbar interbody arthrodesis for degenerative spine diseases: a meta-analysis and systematic review

The aim of this meta-analysis and systematic review is to summarize and critically analyze the influence of surgery-related factors in lumbar interbody fusion for degenerative spine diseases. A systematic review of the literature was carried out with a primary search being performed on Medline through PubMed. The 2009 PRISMA flowchart and checklist were taken into account. Sixty-seven articles were included in the analysis: 48 studies were level IV of evidence, whereas 19 were level III. All interbody fusion techniques analyzed have proved to reach a good fusion rate. An overall mean fusion rate of 93% (95% CI 92-95%, p < 0.001) was estimated pooling the selected studies. The influence of sagittal parameters and cages features in fusion rate was not clear. Autograft is considered the gold standard material. The use of synthetic bone substitutes and biological factors alone or combined with bone graft have shown conflicting results. Low level of evidence studies and high heterogeneity (χ² = 271.4, df = 72, p < 0.001; I² = 73.5%, τ² = 0.05) in data analysis could result in the risk of bias. Further high-quality studies would better clarify these results in the future.

Chemotherapy rechallenge or reintroduction (CTr/r), regofenib (REG) and TAS-102 for metastatic pretreated colorectal cancer (mCRC) patients (pts): A propensity score analysis of treatment beyond second-line (PROSERpINA Study)

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Background: The optimal treatment for mCRC beyond 2nd line is still questioned. Recently, REG and TAS-102 showed to improve survival compared to BSC. While in real-world practice CTr/r is often considered in this setting, supporting evidences are limited. In absence of studies comparing all these strategies, we aimed to compare the prognostic performance of CTr/r, REG and TAS-102 in mCRC treated beyond 2nd line. Methods: mCRC pts progressing after at least 2 lines of CT, treated with CTr/r, REG or TAS-102 between Jan-10 and Jan-19 were considered eligible. The primary endpoint was OS; secondary endpoints were PFS and RR. Cox’s proportional hazard models for survivals were estimated. A propensity score (PS) adjustment for baseline characteristics was further accomplished for survival analysis. Results: The clinical data of 341 pts (CTr/r 133, REG 150, TAS-102 58) were retrospectively collected. At multivariate analysis type of treatment, ECOG PS, number of metastatic sites and treatment line independently correlated with OS ( p < .001, p .001, p < .001 and p .029, respectively). The mOS was 18.5 (95% CI, 14.3–22.7), 6 (95% CI, 5.6–9.5) and 7.6 months (95%CI, 5.6–9.5), for CTr/r, REG and TAS-102 group, respectively (log-rank p < .0001). mOS was significantly longer for pts receiving CTr/r than for those treated with REG/TAS-102 (15.8 vs 7.1 months; adjusted HR 1.96, 95% CI 1.44-2.66; p < .0001) at the PS analysis, adjusted for ECOG PS, number of metastatic sites and treatment line; 2-yrs OS was 34% and 11.6% for CTr/r and REG/TAS-102, respectively. PFS was significantly longer for pts receiving CTr/r than for those treated with REG/TAS-102 (5.5 vs 3.9 months; HR 1.45, 95% CI 1.11-1.91; p .006) at the PS analysis. Accordingly, RR was higher in pts receiving CTr/r compared to REG/TAS-102 (29.0 vs 1.5%; Chi-square p < .00001). Conclusions: Our analysis, although underpowered, generates the hypothesis of a superiority of CTr/r in comparison to REG or TAS-102, in both efficacy and activity. Given the retrospective nature of our analysis, and the potential role of selection bias in treatment assignment, a prospective validation is mandatory.

Colorectal cancer lung metastasis: Could multidisciplinary management suggest the right strategy?

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Background: Unlike liver metastases surgery, the resection of colorectal cancer lung metastasis (CCLM) is not standardized and data are still poor. Therefore, we conducted a retrospective analysis to evaluate the management of CCLM at our Centre. Methods: We retrospectively analyzed patients (pts) with CCLM treated at our Institution from Jan-2007 to Jan-2017. Aim of the study was to evaluate the impact of clinical and pathological features with survival outcomes (DFS and OS). Differences were compared with the use of log-rank test and parameters considered statistically significant ( p value < 0.5) at univariate were compared at multivariate analysis. Results: 141 pts were included in the analysis. 87 pts received a preoperative chemotherapy (pCT) and 54 an adjuvant (a)CT. In the whole population median DFS (mDFS) was 24 m (20-24) and median OS (mOS) 54 m (46-82), while 21 m (20-34) and 65 m (45-108) for pts undergoing pCT and 15 m (20-28) and 53 m (38 – 76) for those receiving aCT respectively, without statistically significant differences (p=0.4). Age, gender, PS, disease-free interval (DFI) (> or <24 months), primary tumor sidedness, mucinous histology, grading, RAS status, timing of lung metastasis (metachronous vs synchronous), number of lesions (>2), metastasis location (uni vs bilateral) and liver resection were evaluated at univariate and multivariate analysis. DFS was correlated with DFI > 24m (p=0.02), timing (p=0.03), number (p<0,0001) of metastasis and metastasis location (p=0.01) whereas OS was associated to DFI (p=0.02), number (p=0.0005), metastasis location (p=0.037) and RAS status (p=0.05) at univariate. At multivariate analysis, number of lesions correlated to DFS (p=0.0006) while DFI (p=0.0034) and RAS status (p=0.05) to OS. Conclusions: Our single Centre retrospective experience suggests an important clinical impact from surgery of CCLM based on mOS of the whole population. These data strengthen the role of a multidisciplinary management to allow pts to achieve surgery whenever possible, regardless of previous liver surgery, metachronous vs synchronous metastasis, DFI and RAS status.

Exosomes as novel prognostic biomarker in potentially resectable colorectal cancer liver metastatic (CCLM) patients

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Background: Target therapies and new surgical strategies deeply modify the history of CCLM patients (pts). Several prognostic scoring systems have been developed but no one is able to identify pts who should be excluded from a potentially useless surgery. Currently research is committed in identifying early biomarkers able to discern pts who could benefit from an aggressive approach. Exosomes are arising as promising biomarkers in cancer. The aim of this pivotal study was to analyze the association among exosome levels during CCLM-pts treatment, clinical outcomes and the KRAS status. Methods: We enrolled 22 pts with CCLM candidate to preoperative chemotherapy (pCT) and subsequent liver surgery. A blood sample was collected before pCT, after surgery, monthly during follow-up and at progression (PD). Exosomes were isolated by ultracentrifugation and characterized by standard methods. Exosomes concentration was assessed by Bradford assay. We adopted ddPCR™ KRAS G12/G13 Screening Kit to evaluate the KRAS status in exosomal DNA (e-DNA). Results: 22 CCLM pts received pCT and underwent liver surgery: 5 major hepatectomies and 17 multiple liver resections. Changes in exosomes plasma levels were found to correlate with each treatment step,resulting reduced after pCT and surgery and increased at PD, respectively (p = 0.0026). Pts with higher baseline exosome levels experimented shorter PFS than those with lower levels (p = 0.0033 HR 0.2). No association was found between exosome levels after liver surgery and disease free interval nor overall survival. KRAS status on e-DNA was evaluated on 10 pts in baseline, in pCT, after surgery, and in PD samples. In 8 out of 10 pts e-DNA displayed the same mutational status than the one detected on tumor DNA. Changes in e-DNA KRAS copies were found statistically significant in pCT vs surgery and pCT vs PD (p = 0.039; p = 0.04). Conclusions: Our study suggests a prognostic role of exosome levels in CCLM pts. Moreover, we showed that KRAS mutational status could be monitored during the post-surgery follow up by analyzing e-DNA. Overall, our data confirm the potential role of exosomes in liquid biopsy tool to monitor molecular changes during the treatment of CCLM pts.

Efficacy of anti-EGFR-based treatment (tx) in second-line and beyond according to tumor location (TL) in RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC) patients (pts): A mono-institutional retrospective analysis

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Background: Right- (R) and left-sided (L) mCRCs exhibit different clinical and molecular features. Several retrospective analyses showed that the survival benefit of anti-EGFR-based tx is limited to RAS/BRAF wt L-sided mCRC pts, with a larger effect in the first-line setting. Few data are available concerning the anti-EGFR efficacy according to TL in 2nd and following lines. Methods: Pts affected by RAS/BRAF wt mCRC treated at our Institution with anti-EGFR-based tx in 2nd and following lines were retrospectively collected. The objective of the analysis was to compare tx activity and efficacy according to TL. Primary endpoint was overall survival (OS); secondary endpoints were progression free survival (PFS) and response rate (RR). Results: A total of 47 RAS/BRAF wt mCRC pts treated with an anti-EGFR-based tx in 2nd and following lines were identified. Of those, 32 (68%) were L-sided and 15 (32%) R-sided, respectively. Pts (age, gender, PS ECOG) and tumor (number of metastatic sites) characteristics and number of tx lines were well balanced between the two 21 pts received anti-EGFR alone, 26 pts anti-EGFR plus CT. mOS was 22.3 in L-sided and 7.3 months in R-sided group (HR 2.3, 95%CI 1.02-5.14, p = 0.04). At multivariate analysis TL and PS ECOG independently correlated with OS ( p = 0.02 and p =0.0089). mPFS was 8.4 and 3.9 months in pts with L-sided and R-sided tumor, respectively (HR 1.3; 95%CI 0.64-2.80, p =0.43). RR was higher in L-sided compared to R-sided tumor (37.5 vs 13.3) ( p= 0.09). Conclusions: Our analysis, although limited by the small sample and by its retrospective nature, indicates a better OS in L-sided compared to R-sided tumors treated with anti-EGFR-based tx in 2nd and following lines. A prospective validation is warranted.

Clinical, pathological and prognostic features of rare BRAF mutations (MTs) in metastatic colorectal cancer (mCRC): A bi-institutional retrospective analysis (REBUS study)

3554

Background: Recently, 3 classes of BRAF MTs have been described. BRAF V600 MTs, which identify mCRC with poor prognosis and not benefitting from anti-EGFR drugs, belong to class 1. Class 2 and 3 include BRAF non-V600 MTs, which occur in about 1-2% mCRC and are associated to favourable prognosis and specific clinicopathologic features. Class 2 and 3 differ in kinase activity and sensitivity to anti-EGFR: class 2 are activated and RAS-independent MTs; class 3 are kinase-dead and sensitive to inhibition of This study aims to retrospectively evaluate features and prognostic role of rare BRAF non-V600 compared to BRAF V600E MTs in mCRC pts treated at 2 Italian Institutions. Methods: mCRC pts harboring BRAF MTs, assessed by means of NGS, pyrosequencing or RT-PCR, treated between Jan-13 and Dec-18 at 2 Italian Institutions, were retrospectively analyzed. Clinico-pathological and treatment characteristics and survival data were collected. Results: 55 pts bearing BRAF MTs were identified. Of those, 46 (84%) harbored a V600E and 9 (16%) a non-V600 MT. Within the non-V600 group, 3 MTs (K601E, G469A, G469R) belonged to class 2, while 5 MTs (G466E, G466A, 2 D594G, D594N), belonged to class 3. One pt harboured a T599I MT, whose kinase activity is unknown. Compared to BRAF V600E mCRC, BRAF non-V600 mCRC were more frequently left-sided ( p .017) and displayed a lower grade ( p .045). In addition, non-V600 mCRC pts had a lower tumor burden (involving one metastatic site) ( p .026) and underwent more frequently to resection of metastases with radical intent (77.7 vs 18%; p .000175). mOS was significantly longer in the non-V600 compared to the V600E group (61.3 vs 20.4 m; HR 0.41, 95%CI 0.18-0.93; p .05). No difference in activity and efficacy of anti-EGFR agents was observed between class 2 and 3. Conclusions: Despite the small size of our retrospective analysis, the results were consistent with previous evidences. BRAF non-V600 MTs identified a subgroup of mCRC, differing both in terms of clinicopathologic characteristics and prognosis from BRAF V600 mCRC. Interestingly, the better prognostic features allowed more frequently radical resection of metastases, positively impacting on survival.

Assessment of Ramucirumab plus paclitaxel as switch maintenance versus continuation of first-line chemotherapy in patients with advanced HER-2 negative gastric or gastroesophageal junction cancers: the ARMANI phase III trial

BACKGROUND

Platinum/fluoropyrimidine regimens are the backbone of first-line chemotherapy for advanced gastric cancer (AGC). However response rates to first line chemotherapy range from 30 to 50% and disease progression occurs after 4-6 cycles. The optimal duration of first-line therapy is still unknown and its continuation until disease progression represents the standard. However this strategy is often associated with cumulative toxicity and rapid development of drug resistance. Moreover, only about 40% of AGC pts. are eligible for second-line treatment.

METHODS

This is a randomized, open-label, multicenter phase III trial. It aims at assessing whether switch maintenance to ramucirumab plus paclitaxel will extend the progression-free survival (PFS) of subjects with HER-2 negative AGC who have not progressed after 3 months of a first-line with a platinum/fluoropyrimidine regimen (either FOLFOX4, mFOLFOX6 or XELOX). The primary endpoint is to compare Progression-Free Survival (PFS) of patients in ARM A (switch maintenance to ramucirumab and placlitaxel) versus ARM B (continuation of the same first-line therapy with oxaliplatin/fluoropyrimidine). Secondary endpoints are: overall survival, time-to-treatment failure, overall response rate, duration of response, percentage of patients that will receive a second line therapy according to arm treatment, safety, quality of life. Exploratory studies including Next-Generation Sequencing (NGS) in archival tumor tissues are planned in order to identify potential biomarkers of primary resistance and prognosis.

DISCUSSION

The ARMANI study estimates if patients treated with early swich with ramucirumab plus paclitaxel received benefit when compared to those treated with continuation of first line therapy. The hypothesis is that the early administration of an active, non-cross resistant second-line regimen such as ramucirumab plus paclitaxel may prolong the time in which patients are progression-free, and consequently have a better quality of life. Moreover, this strategy may rescue all those subjects that become ineligible for second-line therapy due to the rapid deterioration of health status after the first disease progression.

TRIAL REGISTRATION

ARMANI is registered at ClinicalTrials.gov ( NCT02934464 , October 17, 2016) and EudraCT(2016-001783-12, April 202,016).

Histology could predict a “hot” or a “cold” gastric tumor?

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Background: The emerging role of immunotherapy (IT) in cancer treatments has increased the research about tumor microenvironment (TME), tumor infiltrating lymphocytes (TILs) function and their TME regulation. Nowadays ongoing trial are showing conflicting preliminary data about the efficacy of IT in advanced gastric cancer (GC). Therefore, we performed this exploratory analysis to evaluate the correlation between histology, TILs density (reported as CD4/CD8 tissue ratio), neutrophil-lymphocytes ratio (NLR) and response outcome in GC patients who underwent cytotoxic neoadjuvant treatment (NAD). Methods: CD4+ and CD8+ expression was assessed by immunohistochemistry (IHC) in pre-NAD biopsies. NLR was calculated on baseline complete blood count. A cut-off value to define low or high NLR has been selected on 3.0, based on literature data. X2 test was used to explore the correlation between histology, CD4/CD8 ratio, NLR and response. Results: We analyzed 10 diffuse and 10 intestinal GC histotypes. In the intestinal-type CD4/CD8 ratio was lower (ratio range 1:15 - 1:20) with a predominant count of CD8+ suggesting a hot and inflamed TME compared to the diffuse cohort (ratio range 1:3 -1:5) where both CD8+ and CD4+ density was lower (p=0.03). Baseline NLR was calculated in 18 out of 20 pts. All intestinal GCs showed a low NLR (<3) while all diffuse GCs displayed a high cutoff (p=0.03). CD4/CD8 ratio resulted associated to histology (p=0.025) and response outcome (p=0.0003). NLR was statistically related to histology (p=0.03) and CD4/CD8 tissue ratio (p=0.03), confirming a different systemic inflammatory status and TME according to histology. Conclusions: Despite the small sample size, our exploratory analysis shows a possible correlation between histology, systemic inflammation and TME behavior (“hot” vs“cold”) described by NLR and TILs concentration (CD4/CD8 ratio) respectively and response to NAD. Intestinal-type seems to be a “hot” tumor whereas diffuse-type appears “cold”. Future clinical trial should analyze the impact of histology and TME features on IT efficacy and the appropriate strategy to convert “cold” tumor increasing TILs density.

Interventional oncology treatments for unresectable early stage HCC in patients with a high risk for intraprocedural bleeding: Is a single-step combined therapy safe and feasible?

PURPOSE

This study was designed to assess the feasibility and safety of a single-step combined therapy using radiofrequency ablation and transarterial chemoembolization (RFA + TACE) in patients with hepatocellular carcinoma (HCC) and uncontrolled coagulopathy. The study also aimed to compare the effectiveness of this approach with TACE alone, performed in a control group.

MATERIAL AND METHODS

One hundred and forty-three consecutive cirrhotic patients having a single HCC < 8 cm were enrolled in this observational prospective single-center study from January 2010 to June 2017 and were divided, according to coagulation tests, into three groups (A: low risk; B: intermediate risk and C: high risk of bleeding). The feasibility and safety of a single-step combined treatment (RFA followed by TACE) were evaluated in terms of technical success rate, periprocedural complications, and laboratory values variations. Tumor response obtained at 1-month CT follow-up for group C was compared with that of control group, composed by 16 matched patients with severe coagulopathy and single HCC < 8 cm, who underwent only TACE in a previous period, performed by the same operator.

RESULTS

Technical success was achieved in all patients, without any major complications. Minor complications rate was significantly higher in group C after RFA; however, the patients were successfully treated with subsequent TACE therapy, without any differences between pre- and post-procedural laboratory values. One-month complete response rates were similar in all the three groups; however, the response rates of group C were significantly higher as compared to that of the control TACE Group (p < .001).

CONCLUSION

The single-step RFA plus TACE therapy allows expansion of the indication for percutaneous thermal ablation, allowing to also include cases previously contraindicated due to the procedural high-risk of complications associated with bleeding, thus improving short-term patient outcome.

Malignant Pleural Mesothelioma: Is Tailoring the Second-Line Therapy Really "Raising the Bar?"

OPINION STATEMENT

Unresectable or relapsed malignant pleural mesothelioma (MPM) has dismal prognosis. First-line combination therapy with pemetrexed and a platinum analog allows a modest survival benefit, while no clear therapeutic options exist for the second-line therapy. In this setting, pemetrexed seems to be the most active drug; however, the inclusion in front-line treatment limits its use in further lines. Nevertheless, rechallenge with one or both drugs used in first-line remains a feasible strategy for responder patients. Alternatively, only few cytotoxic drugs have demonstrated a mild activity in refractory MPM. Among other options, targeted therapy has unfortunately produced disappointing results as salvage treatment probably due to the lack of a clear understanding of the tumor biology. In contrast, recent data suggest moderate efficacy and mild toxicity of immunotherapy also for the treatment of MPM. The combination of checkpoint inhibitors with chemotherapy or other immunological agents seems promising and could really "raise the bar" in this setting.

The impact of multidisciplinary team (MDT) management on outcome of hepatic resection in liver-limited colorectal metastases

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Background: Hepatic resection is the gold standard treatment for pts with liver-limited mCRC with 5- and 10-yrs survival rates reaching up to 60% and 20%. Although multidisciplinary team (MDT) management might ensure a more accurate assessment of pts and a faster referral to surgeons, reports discussing the impact of MDTs on survival are controversial and to date there are no strong evidences supporting routinely MDT discussion. The aim of this study was to evaluate the benefit of MDT management in pts with liver-limited mCRC in our single institution experience. Methods: Clinical records of pts with liver-limited mCRC who underwent radical surgery at Fondazione Policlinico “A. Gemelli” - IRCCS from Jan-2006 to Dec-2016 were retrospectively analyzed. The objective of the analysis was to compare survivals of pts managed within our MDT (MDT cohort) to those of pts referred to surgery from other hospitals without MDT discussion (non-MDT cohort). Primary endpoints were DFS and OS. Differences in baseline characteristics and in post-operative morbidity were evaluated. Results: Of the 619 pts analyzed, 230 were included in the MDT cohort and 389 in the non-MDT cohort. No significant difference between the two groups was found in terms of DFS (12vs11 m; p 0.09) and OS (55vs51 m; p 0.68). Concerning baseline characteristics, in the MDT cohort compared to non-MDT cohort there was a statistically higher number of median metastases (4.5vs2.6; p < 0.0001) and a higher rate of synchronous metastases (61.7vs39.3%; p < 0.001). Despite pre-operative CT rate was higher in the MDT group (75.8vs70.7%), the median duration of CT before surgery was significantly lower in MDT pts (7 vs 8 cycle; p < 0.001). Moreover, post-operative morbidity was significantly lower in the MDT cohort (6.2vs19.2%; p < 0.00001). Conclusions: Our study does not demonstrate a survival benefit from MDT management of pts with liver limited mCRC. However, the analysis shows that MDT assessment allows to consider eligible for surgery pts with a more advanced disease. Moreover, MDT discussion seems to reduce the median duration of pre-operative CT with a consequent lower rate of post-operative morbidities. Our data warrant prospective validation.

FOLFOX rechallenge versus regorafenib in patients with metastatic colorectal cancer refractory to standard chemotherapy: A retrospective analysis

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Background: Nowadays the optimal treatment for mCRC beyond second line is still questioned. During last years, regorafenib and TAS-102 showed to improve survival compared to best supportive care in pts with refractory mCRC. Recently, some retrospective analyses compared the efficacy and safety of regorafenib and TAS-102 reporting no significant differences in survival and response outcomes. In real-world clinical practice, chemotherapy (CT) rechallenge is often considered for refractory mCRC. However, evidences regarding CT rechallenge is limited and no study has previously compared such approach with the recently approved antineoplastic agents in late lines. The aim of this study was to compare the efficacy between CT rechallenge and regorafenib in pts with refractory mCRC. Methods: This is a mono-institutional retrospective study. We compared the efficacy of FOLFOX rechallenge and regorafenib in pts with mCRC refractory to at least 2 lines of standard CT, treated at Fondazione Policlinico Universitario “A. Gemelli”-IRCCS between Jan-10 and Jan-18. The primary endpoint was OS. Secondary endpoints were RR and PFS. Results: One hundred thirty-one pts received regorafenib and 43 FOLFOX rechallenge. OS was significantly higher with FOLFOX rechallenge than it was with regorafenib (13 vs. 6 months; HR 0.67, 95% CI 0.33-0.66; p = 0.0002). PFS was significantly higher in the FOLFOX rechallenge group compared to the regorafenib group (5 vs. 3 months; HR 0.64, 95% CI 0.46-0.89; p = 0.0073). Accordingly, RR was better in pts receiving FOLFOX rechallenge compared to regorafenib (25 vs. 3%; Chi-square p < 0.0001). Conclusions: Our study, although retrospective and small-sized, compared for the first time to our knowledge the efficacy of CT rechallenge to regorafenib in refractory mCRC. In our analysis, CT rechallenge with FOLFOX proved to be superior compared to regorafenib, with a survival and response benefit in pretreated mCRC. The survival benefit observed for rechallenge might be explained by the significantly higher tumor shrinkage achieved with CT rechallenge compared to regorafenib. Our results warrant further confirmation in wider and/or prospective analyses.

Locally advanced gastric cancer (LAGC): Does histology suggest strategy in PAN-cancer Era?

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Background: Surgery is the only potentially curative treatment for LAGC. Evidences suggest that perioperative CT (pCT) plus surgery is superior to surgery alone, whereas studies on adjuvant CT (aCT) are controversial. Guidelines recommend a pCT approach in pts with stage II/III, nevertheless in real-life many pts receive immediate surgery followed by aCT. Histology influences both survival and pathological response with worse prognosis among diffuse LAGC. No trial has compared pCT and aCT or investigated the impact of histology on the outcome of these different approaches. We hypothesized that histology may predict a different benefit from CT administered in the two settings, allowing to define the optimal strategy. We performed a study comparing the two approaches according to histology. Methods: We retrospectively analyzed pts with stage II/III LAGCs treated at our Institution between Jan-09 and Jan-17. The objective of the study was to evaluate the impact of histology (intestinal and diffuse) on survival according to strategy approach (pCT vs aCT). Primary endpoints were DFS and OS. Results: 81 pts had diffuse LAGC (29 received pCT, 52 aCT) and 60 had intestinal LAGC (32 received pCT, 29 aCT). In the intestinal cohort both DFS and OS were significantly higher in pts treated with pCT compared to aCT (DFS: HR 0.3, p = 0.02; OS: HR 0.3, p = 0.03). On the contrary in the diffuse cohort both DFS and OS were significantly lower in pts receiving pCT compared to those receiving aCT (DFS: HR 2.4, p = 0.0014; OS: HR 2.6, p = 0.0012). Conclusions: Our study, although retrospective and small-sized, shows that the survival benefit of pCT is limited to intestinal LAGC, whereas in diffuse LAGC the administration of pCT appears detrimental. Indeed, diffuse LAGC is known to be chemoresistant and pCT might delay surgery allowing metastasization. Despite the arising of recent molecular classification, still far from modifying clinical practice, histotype might represent an easy factor to discriminate pts benefitting from pCT (intestinal) to those in whom upfront surgery might be recommended (diffuse). Our hypothesis needs to be confirmed in prospective trials.

Direct Oral Anticoagulants and Medical Comorbidities in Patients Needing Dental Extractions: Management of the Risk of Bleeding

PURPOSE

The purpose of this study was to measure the frequency of bleeding during and after tooth extraction in patients exposed to direct oral anticoagulants (DOACs) and identify risk factors for prolonged or excessive bleeding.

MATERIALS AND METHODS

This retrospective cohort study involved 100 patients who underwent tooth extractions according to the European Heart Rhythm Association protocol: continuation of DOAC therapy for extractions of up to 3 teeth in the same session performed at the (presumed) time of DOAC trough concentration. We respected an interval of at least 4 hours between extraction and last DOAC intake. The outcome of interest was incidence of mild, moderate, and severe bleeding during the intervention and in the 7-day follow-up period. Data analysis considered the presence of comorbidities as the primary predictor for bleeding; additional predictors were age, gender, type of comorbidity, indication for DOAC therapy, DOAC agent, and extraction of contiguous teeth.

RESULTS

Of the patients, 64 had comorbidities (diabetes in 50%). The distributions of demographic, clinical, and dental variables were similar for patients with and without comorbidities. We observed 4 bleeding episodes (1 moderate episode 1 hour after the extraction and 3 mild episodes the day after the extraction) in the comorbidity group and none in the non-comorbidity group (4 of 64 vs 0 of 36, P = .29; overall bleeding rate, 4 of 100). The factor significantly triggering bleeding in patients with comorbidity was extractions of couples and triplets of multirooted teeth (P = .004).

CONCLUSIONS

Tooth extractions in patients with comorbidities taking DOACs may be safely managed as long as they are performed at least 4 hours after the last DOAC intake and do not involve 2 or 3 contiguous premolars and molars.