A phase II/III randomized clinical trial of CisPlatin plUs Gemcitabine and Nabpaclitaxel (GAP) as pReoperative chemotherapy versus immediate resection in patIents with resecTable BiliarY Tract Cancers (BTC) at high risk for recurrence: PURITY study

BACKGROUND

Biliary tract cancers (BTCs) are rare and lethal cancers, with a 5-year survival inferior to 20%(1-3). The only potential curative treatment is surgical resection. However, despite complex surgical procedures that have a remarkable risk of postoperative morbidity and mortality, the 5-year survival rate after radical surgery (R0) is 20-40% and recurrence rates are up to ~ 75%(4-6). Up to ~ 40% of patients relapse within 12 months after resection, and half of these patient will recur systemically(4-6). There is no standard of care for neoadjuvant chemotherapy (NAC) in resectable BTC, but retrospective reports suggest its potential benefit (7, 8).

METHODS

PURITY is a no-profit, multicentre, randomized phase II/III trial aimed at evaluating the efficacy of the combination of gemcitabine, cisplatin and nabpaclitaxel (GAP) as neoadjuvant treatment in patients with resectable BTC at high risk for recurrence. Primary objective of this study is to evaluate the efficacy of neoadjuvant GAP followed by surgery as compared to upfront surgery, in terms of 12-month progression-free survival for the phase II part and of progression free survival (PFS) for the phase III study. Key Secondary objectives are event free survival (EFS), relapse-free survival, (RFS), overall survival (OS), R0/R1/R2 resection rate, quality of life (QoL), overall response rate (ORR), resectability. Safety analyses will include toxicity rate and perioperative morbidity and mortality rate. Exploratory studies including Next-Generation Sequencing (NGS) in archival tumor tissues and longitudinal ctDNA analysis are planned to identify potential biomarkers of primary resistance and prognosis.

DISCUSSION

Considering the poor prognosis of resected BTC experiencing early tumor recurrence and the negative prognostic impact of R1/R2 resections, PURITY study is based on the rationale that NAC may improve R0 resection rates and ultimately patients' outcomes. Furthermore, NAC should allow early eradication of microscopic distant metastases, undetectable by imaging but already present at the time of diagnosis and avoid mortality and morbidity associated with resection for patients with rapid progression or worsening general condition during neoadjuvant therapy. The randomized PURITY study will evaluate whether patients affected by BTC at high risk from recurrence benefit from a neoadjuvant therapy with GAP regimen as compared to immediate surgery.

TRIAL REGISTRATION

PURITY is registered at ClinicalTrials.gov (NCT06037980) and EuCT(2023-503295-25-00).

Circulating microRNA analysis in a prospective co-clinical trial identifies MIR652-3p as a response biomarker and driver of regorafenib resistance mechanisms in colorectal cancer

BACKGROUND

The multi-kinase inhibitor regorafenib has demonstrated efficacy in chemo-refractory metastatic colorectal cancer (mCRC) patients. However, lack of predictive biomarkers and concerns over significant toxicities hamper the use of regorafenib in clinical practice.

METHODS

Serial liquid biopsies were obtained at baseline and monthly until disease progression in chemo-refractory mCRC patients treated with regorafenib in a phase II clinical trial (PROSPECT-R n=40; NCT03010722) and in a multicentric validation cohort (n=241). Tissue biopsies collected at baseline, after 2 months and at progression in the PROSPECT-R trial were used to establish Patient-Derived Organoids (PDOs) and for molecular analyses. MicroRNA profiling was performed on baseline bloods using the NanoString nCounter platform and results were validated by digital droplet PCR and/or In Situ Hybridization in paired liquid and tissue biopsies. PDOs co-cultures and PDO-xenotransplants were generated for functional analyses.

RESULTS

Large-scale microRNA expression analysis in longitudinal matched liquid and tissue biopsies from the PROSPECT-R trial identified MIR652-3p as a biomarker of clinical benefit to regorafenib. These findings were confirmed in an independent validation cohort and in a "control" group of 100 patients treated with lonsurf. Using ex vivo co-culture assays paired with single-cell RNA-sequencing of PDO established pre- and post-treatment, we modelled regorafenib response observed in vivo and in patients, and showed that MIR652-3p controls resistance to regorafenib by impairing regorafenib-induced lethal autophagy and by orchestrating the switch from neo-angiogenesis to vessel co-option.

CONCLUSIONS

Our results identify MIR652-3p as potential biomarker and as a driver of cell and non-cell autonomous mechanisms of resistance to regorafenib.

Adding fasting-mimicking diet to first-line carboplatin-based chemotherapy is associated with better overall survival in advanced triple-negative breast cancer patients: A subanalysis of the NCT03340935 trial

Severe calorie restriction, in the form of cyclic fasting or fasting-mimicking diets (FMDs), boosts the antitumor activity of cytotoxic chemotherapy in mouse models of triple-negative breast cancer (TNBC). This effect is mostly mediated by fasting/FMD-induced reduction of plasma glucose concentration and by a boost in antitumor immunity. However, clinical evidence that cyclic FMD may impact on the outcomes of advanced TNBC (aTNBC) patients is lacking. We compared the overall survival (OS) of 14 aTNBC patients receiving first-line carboplatin-gemcitabine plus cyclic FMD in the context of the NCT03340935 trial with the OS of 76 consecutive aTNBC patients treated with carboplatin-based chemotherapy alone at Fondazione IRCCS Istituto Nazionale dei Tumori. Multivariable Cox regression models were used to adjust the prognostic impact of FMD for other prognostic variables. Patients undergoing cyclic FMD in combination with carboplatin-gemcitabine had better OS when compared to patients receiving chemotherapy alone (median OS 30.3 months, 95% CI 18-NR, vs 17.2 months, 95% CI 15.3-25.1, log-rank P value .041). Multivariable analysis confirmed an association between FMD use and better OS (HR: 0.40; 95% CI: 0.19-0.86; P = .019) also after propensity score-based matching according to patient ECOG PS and the presence of de novo metastatic disease (HR: 0.41; 95% CI: 0.21-0.83; P = .013). Cyclic FMD in combination with first-line chemotherapy may improve clinical outcomes in aTNBC patients. Our study paves the way for conducting phase II trials to investigate if cyclic FMD can increase the antitumor activity/efficacy of chemotherapy or chemoimmunotherapy in patients with early-stage TNBC or aTNBC.

High bone tumor burden to identify advanced non-small cell lung cancer patients with survival benefit upon bone targeted agents and immune checkpoint inhibitors

BACKGROUND

Bone-targeted agents (BTA), such as denosumab (DN) and zoledronic acid (ZA), have historically reduced the risk of skeletal related events in cancer patients with bone metastases (BM), with no improvement in survival outcomes. In the immunotherapy era, BM have been associated with poor prognosis upon immune-checkpoint inhibitors (ICI). Currently, the impact of bone tumor burden on survival upon BTAs in advanced non-small cell lung cancer (aNSCLC) patients treated with ICI remains unknown.

METHODS

Data from ICI-treated aNSCLC patients with BM (4/2013-5/2022) in one institution were retrospectively collected. BTA-ICI concurrent treatment was defined as BTA administration at any time before or within 90 days from ICI start. High bone tumor burden (HBTB) was defined as ≥ 3 sites of BM. Median OS (mOS) was estimated with Kaplan-Meier. Aikaike's information criterion (AIC) was used to select the best model for data analysis adjusted for clinical variables.

RESULTS

Of 134 patients included, 51 (38 %) received BTA. At a mFU of 39.6 months (m), BTA-ICIs concurrent treatment did not significantly impact on mOS [8.3 m (95% CI 3.9-12.8) versus (vs) 6.8 m (95% CI 4.0-9.6) p = 0.36]; these results were confirmed after adjustment for clinical variables selected by AIC. A multivariate model showed a significant interaction between BTA use and HBTB or radiation therapy to BM. In subgroup analyses, only HBTB confirmed to be associated with significantly longer mOS [8.3 m (95% CI 2.4-14.2) vs 3.5 m (95% CI 2.9-4.1), p = 0.003] and mPFS [3.0 m (95% CI 1.6-4.4) vs 1.8 m (95% CI 1.6-2.0) p = 0.001] upon BTA-ICI concurrent treatment, with the most pronounced OS benefit observed for DN-ICI concurrent regimen [15.2 m (95% CI 0.1-30.7) vs 3.5 m (95% CI 2.9-4.1) p = 0.002].

CONCLUSIONS

In the immunotherapy era, HBTB can identify patients experiencing survival benefit with BTA, especially with DN-ICI combination. HBTB should be included as a stratification factor in the upcoming trials assessing BTA and ICI combinations in patients with aNSCLC and BM.

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

PURPOSE

Prognostic tools to estimate the risk of relapse for patients with liver-limited metastatic colorectal cancer (LL-mCRC) undergoing resection with curative intent are needed. Circulating tumor DNA (ctDNA) as a surrogate of postsurgical minimal residual disease is a promising marker in localized CRC. We explored the role of postoperative ctDNA as a marker of minimal residual disease in patients with radically resected LL-mCRC.

MATERIALS AND METHODS

Seventy-six patients with LL-mCRC were retrospectively included. DNA from tumor tissue was sequenced, and one somatic mutation was then assessed by digital droplet polymerase chain reaction in plasma samples collected after surgery to identify the persistence of ctDNA. Relapse-free survival and postresection overall survival were compared between patients with positive vs negative postoperative ctDNA.

RESULTS

ctDNA was found in 39 (51%) of 76 patients with LL-mCRC. At a median follow-up of 77 months, 33 of 39 ctDNA-positive patients and 20 of 37 ctDNA-negative patients experienced disease relapse ( P = .008). ctDNA-positive patients reported significantly shorter RFS than ctDNA-negative ones (median RFS 12.7 v 27.4 months hazard ratio, 2.09, P = .008). In the multivariable model including other prognostic covariates, this association was still significant ( P = .046) and a trend toward shorter overall survival among ctDNA-positive patients was reported (hazard ratio, 1.65, P = .183).

CONCLUSION

The detection of postsurgical ctDNA is an independent negative prognostic marker and identifies patients at high risk of relapse after liver metastases resection.

Abstract 2380: The effect of metabolic alterations on chemo-immunotherapy response in non-small-cell lung cancer model

Introduction: Lung cancer is one of the leading cause of cancer death worldwide, with an estimate incidence of about 2 million new cases per year. Among all lung cancers, non-small-cell lung cancer (NSCLC) is the most frequent (nearly 85%) with a 5-year survival of about 25% when all stages are considered.NSCLCs are frequently mutated in KRAS or STK11/LKB1 and co-mutation is often reported. Considering the key role of STK11/LKB1 in controlling cell metabolism, we hypothesized that NSCLC harboring mutations in this gene could be vulnerable to metabolic stresses. Different studies in the last years have highlighted how is possible to interfere with cancer metabolism using metformin and caloric restriction.Our work aimed at investigating the role of metabolic stress in determining response to chemotherapy and immunotherapy in LKB1 mutated NSCLC model.

Methods: For isolation of cell lines with the genetic backgrounds, nodules from lungs of KRASG12D/LKB1wt and KRASG12D/LKB1mut transgenic mice were used. Stabilized cell lines were then inoculated intramuscularly in immunocompetent mice and treated with chemotherapy alone (cisplatin) or in combination with metformin and caloric restriction. Caloric restriction consisted of 36 hours of fasting every week for three weeks. Metformin was administered daily for the entire experiment while cisplatin was given once a week for three weeks.

Results: We started our in vivo experiments comparing the response of the tumors characterized by the mutation in KRASG12D or the co-mutation KRASG12D/LKB1mut. The results indicate that the addition of metformin and caloric restriction improve the activity of cisplatin in both tumors but a stronger effect was detected in tumors presenting the deletion of LKB1. In fact, only in the latter group, the effect of the combination lasted beyond the end of the treatment slowing down the tumor growth. The different combinations were well tolerated. Molecular analysis on tumor samples run in parallel are in progress.

Conclusion: Our in vivo preliminary studies confirm our hypothesis that the addition of the caloric restriction and metformin is able to improve the antitumor activity of the cisplatin without increasing the treatment toxicity in tumors characterized by the co-mutations of KRASG12D/LKB1mut. Further investigations are ongoing on the role of metabolic stress in addition to the immunotherapy (using anti PD-1 antibody as immunocheckpoint inhibitor).

Citation Format: Gloriana Ndembe, Mirko Marabese, Ilenia Intini, Alessandra Fabbri, Massimo Moro, Mario Occhipinti, Elisa Sottotetti, Giuseppe Lo Russo, Monica Ganzinelli, Massimo Broggini. The effect of metabolic alterations on chemo-immunotherapy response in non-small-cell lung cancer model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2380.

PEOPLE (NTC03447678), a phase II trial of first-line, single-agent pembrolizumab in advanced NSCLC with low PD-L1: Clinical outcomes and association with circulating immune biomarkers

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Background: In advanced NSCLC (aNSCLC) with PD-L1 < 50% chemo-immunotherapy is the standard of care. Although the activity of single agent pembrolizumab was reported, no biomarkers have been identified able to select patients who mostly benefit. The trial aimed to identify immune biomarkers associated with PFS in aNSCLC patients with PD-L1 levels < 50% treated with first-line pembrolizumab. Here we reported for the first time the clinical outcomes of the trial and circulating immune profiling (CIP) biomarkers correlated to PFS. Methods: This phase II trial was conducted at Fondazione IRCCS Istituto Nazionale dei Tumori of Milan. Eligible patients were previously untreated stage IIIB-IV NSCLC, EGFR and ALK wild type with PD-L1 < 50%, PS 0-2. PD-L1 was assessed with 22-C3 antibody (Dako). Patients received pembrolizumab 200 mg every 3 weeks until 35 cycles, disease progression or unacceptable toxicity. The primary endpoint was the association of immune biomarkers with PFS. OS, ORR, DCR, DoR and safety were secondary endpoints. CIP was performed by determination of absolute cell counts for 36 innate and adaptive immunity subsets through multiparametric flow cytometry on freshly isolated whole blood samples at baseline. An orthoblique principal components-based clustering approach and multivariable Cox regression model adjusted for clinical variables were used to analyse CIP variables and their correlation with clinical endpoints. Results: From May 2018 to October 2020, of 87 screened, 65 patients were enrolled. The median age was 70.9 years, most patients were male (67.7%), smoker (87.7%), non-squamous (83.1%), PDL1 + (70.8%). 12 patients (18.5%) had PS 2. During a median follow-up of 26.4 months (mo), 51 radiological progressions, 46 deaths and 60 PFS events were observed. The median PFS was 2.9 mo (95%CI 1.8 - 5.6) and the median OS was 12.1 mo (95%CI 8.7 - 17.1). The ORR was 24.1% (2 complete and 12 partial responses), DCR was 53.4% and median DoR was 14.5 mo (95%CI 6.4 - 24.9). Drug related G3-G4 adverse events were: 2 hyponatremia, 2 lipase increased, 1 pneumonitis. Out of 7 CIP clusters identified, 2 were statistically significant at multivariable analysis on 57 patients. Higher baseline counts of 8 subsets within these two clusters were associated with better PFS (HR values range: 0.88-0.98; p values range: 0.001- 0.016). The significant subsets included lymphocytes (cells expressing CD3, or CD19 or CD56, but lacking granulocyte and monocyte markers) and main NK subsets (including CD56dim CD16+, CD56dim CD16- and HLA-DR+ NK cells). Conclusions: This trial confirmed that pembrolizumab as first-line single agent is safe and active also in a subgroup of aNSCLC patients with PD-L1 < 50%. CIP biomarkers can be useful to identify patients with a favourable outcome, thus avoiding the adding toxicity of chemotherapy. Clinical trial information: NTC03447678.

ALK Inhibitors in Patients With ALK Fusion-Positive GI Cancers: An International Data Set and a Molecular Case Series

In GI cancers, anaplastic lymphoma kinase (ALK) rearrangements are extremely less frequent than in non–small-cell lung cancer but may be important to offer personalized strategies of treatment in selected patients. Data about the activity and efficacy of ALK inhibitors (ALKi) in GI cancers are scarce.

ALK inhibitors are active in patients with ALK fusion–positive GI cancers.

Variant allele frequency in baseline circulating tumour DNA to measure tumour burden and to stratify outcomes in patients with RAS wild-type metastatic colorectal cancer: a translational objective of the Valentino study

INTRODUCTION

In patients with metastatic colorectal cancer (mCRC), baseline circulating tumour DNA (ctDNA) variant allele fraction (VAF) might serve as a surrogate of disease burden and should be evaluated in comparison with CEA and RECIST-defined sum of target lesions.

METHODS

In this pre-planned analysis of the VALENTINO trial, we included patients with RAS wild-type mCRC receiving upfront FOLFOX/panitumumab with available baseline liquid biopsy. CtDNA was analysed by means of a 14-gene NGS panel. For each patient, the gene with the highest VAF in ctDNA was selected.

RESULTS

The final cohort included 135 patients. The median VAF was 12.6% (IQR: 2.0-45.2%). Higher VAF was observed in patients with liver metastases and with synchronous metastases presentation. Patients with high VAF had poorer median OS compared to those with low VAF (21.8 vs 36.5 months; HR: 1.82, 95%CI: 1.20-2.76; p = 0.005). VAF outperformed baseline CEA and target lesion diameter in the prognostic stratification and remained significantly correlated with OS (p = 0.003) in a multivariate model. VAF was not significantly correlated with dimensional response and PFS.

CONCLUSION

CtDNA measured by VAF is prognostic in patients with RAS wild-type mCRC. Response and PFS after an anti-EGFR-based first-line strategy are independent from initial tumour burden.

Efficacy of mRNA anti-SARS-CoV-2 vaccination and dynamics of humoral immune response in patients with solid tumors: results from the institutional registry of an Italian tertiary cancer center

Background:

Systemic immunosuppression characterizing cancer patients represents a concern regarding the efficacy of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, and real-world evidence is needed to define the efficacy and the dynamics of humoral immune response to mRNA-based anti-SARS-CoV-2 vaccines.

Methods:

We conducted an observational study that included patients with solid tumors who were candidates for mRNA anti-SARS-CoV-2 vaccination at the Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy. The primary objective was to monitor the immunologic response to the mRNA anti-SARS-CoV-2 vaccination in terms of anti-spike antibody levels. All the patients received two doses of the mRNA-1273 vaccine or the BNT162b2 vaccine. Healthcare workers served as a control group of healthy subjects.

Results:

Among the 243 patients included in the present analysis, 208 (85.60%) and 238 (97.94%) resulted seroconverted after the first and the second dose of vaccine, respectively. Only five patients (2.06%) had a negative titer after the second dose. No significant differences in the rate of seroconversion after two vaccine doses were observed in patients as compared with the control group of healthy subjects. Age and anticancer treatment class had an independent impact on the antibody titer after the second dose of vaccination. In a subgroup of 171 patients with available data about the third timepoint, patients receiving immunotherapy with immune checkpoint inhibitors seem to have a higher peak of antibodies soon after the second dose (3 weeks after), but a more pronounced decrease at a late timepoint (3 months after).

Conclusions:

The systemic immunosuppression characterizing cancer patients did not seem to dramatically affect the humoral response to anti-SARS-CoV-2 mRNA vaccines in our population of patients with solid tumors. Further investigation is needed to dissect the interplay between immunotherapy and longitudinal dynamics of humoral response to mRNA vaccines, as well as to analyze the cellular response to mRNA vaccines in cancer patients.

Immune-Checkpoint Inhibitors in Advanced Non-Small Cell Lung Cancer With Uncommon Histology

BACKGROUND

Immune-checkpoint inhibitors (ICIs) have significantly improved outcome of advanced non-small cell lung cancer (aNSCLC) patients. However, their efficacy remains uncertain in uncommon histologies (UH).

MATERIALS AND METHODS

Data from ICI treated aNSCLC patients (April,2013-January,2021) in one Institution were retrospectively collected. Univariate and multivariate survival analyses were estimated by Kaplan-Meier and Cox proportional hazards regression model, respectively. Objective response rate (ORR) and disease control rate (DCR) were assessed.

RESULTS

Of 375 patients, 79 (21.1%) had UH: 19 (24.1%) sarcomatoid carcinoma, 15 (19.0%) mucinous adenocarcinoma, 10 (12.6%) enteric adenocarcinoma, 8 (10.1%) adenocarcinoma not otherwise specified, 7 (8.9%) large-cell neuroendocrine carcinoma, 6 (7.6%) mixed histology non-adenosquamous, 5 (6.3%) adenosquamous carcinoma, 9 (11.4%) other UH. In UH group, programmed death-ligand 1 (PD-L1) <1%, 1-49%, ≥50% and unknown expression were reported in 27.8%, 22.8%, 31.7% and 17.7% patients respectively and ICI was the second/further-line in the majority of patients. After a median follow-up of 35.64 months (m), median progression-free survival (mPFS) was 2.5 m in UH [95% CI 2.2-2.9 m] versus (vs.) 2.7 m in CH [95% CI 2.3-3.2 m, P-value = .584]; median overall survival (mOS) was 8.8 m [95% CI 4.9-12.6 m] vs. 9.7 m [95% CI 8.0-11.3 m, P-value = .653]. At multivariate analyses only ECOG PS was a confirmed prognostic factor in UH. ORR and DCR were 25.3% and 40.5% in UH vs. 21.6% and 49.5% in CH [P-value = .493 and .155 respectively].

CONCLUSIONS

No significant differences were detected between UH and CH groups. Prospective trials are needed to understand ICIs role in UH population.

Angiopoietin-2 early increase to predict benefit from regorafenib in metastatic colorectal cancer (mCRC) patients: The prospective REGOLAND study

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Background: Regorafenib is a treatment option for refractory mCRC patients with no validated predictors of benefit. We previously showed that, among several circulating angiogenic factors, low baseline Ang-2 and Tie-2 plasma levels were associated with good prognosis and that the early increase of Ang-2 during the treatment could predict benefit from regorafenib ( Antoniotti et al, J Clin Oncol 36:675-675, 2018). To prospectively validate these retrospective findings, we conducted the REGOLAND study. Methods: Ang-2 and Tie-2 were assessed by ELISA on plasma samples collected at baseline (d1) and after 15 days (d15) of treatment in a cohort of mCRC patients receiving regorafenib, as per indication. To detect a HR for PFS of 0.50 in favour of the early increase (Δd15-d1) of Ang-2 levels, setting two-sided α = 0.05 and β = 0.10, 87 events were required according to Schoenfeld design. Comparisons among concentrations of each marker at d1 and d15 were performed by Wilcoxon test. Median values at baseline were used as cut-off to discriminate patients with low versus high plasma levels and their correlation with outcome was analysed. Results: One hundred patients were included. Median PFS and OS were 2.5 and 6.7 months, respectively. The early increase of Ang-2 at d15 was reported in 42 patients and was associated with longer PFS (median 2.7 vs 2.4 months; HR for PFS: 0.72 [95%CI:0.48-1.08], P = 0.095). As compared to d1, an overall decrease of Tie-2 levels at d15 was observed ( P = 0.007), but it was not associated with clinical outcome. Low levels of Ang-2 at baseline were associated with longer PFS (HR: 0.59 [95%CI:0.39-0.89], P = 0.005) and OS (HR:0.62 [95%CI:0.41-0.94], P = 0.017), while Tie-2 levels were not. In the multivariate model, the association of Ang-2 levels with PFS was confirmed (HR:0.48 [95%CI:0.31-0.76], P = 0.001), but not with OS (HR: 0.80 [95%CI:0.49-1.28], P = 0.351). Conclusions: Ang-2 is a prognostic marker and its early modulation predicts clinical benefit among mCRC patients treated with regorafenib. We hypothesize that Ang-2 levels early increase as a consequence of the successful inhibition of Tie-2 by regorafenib that leads to a compensatory increase of the ligand and correlates with anti-tumour activity.

The Added Value of Baseline Circulating Tumor DNA Profiling in Patients with Molecularly Hyperselected, Left-sided Metastatic Colorectal Cancer

PURPOSE

The routine use of liquid biopsy is not recommended for the choice of initial treatment for patients with metastatic colorectal cancer (mCRC).

EXPERIMENTAL DESIGN

We included patients with left-sided, RAS/BRAF wild-type, HER2-negative, and microsatellite stable mCRC, treated with upfront panitumumab/FOLFOX-4 in the Valentino study. We performed amplicon-based genomic profiling of 14 genes in baseline plasma samples and compared these data with tumor tissue ultra-deep sequencing results. Specific gene mutations in circulating tumor DNA (ctDNA) and their clonality were associated with progression-free survival (PFS), overall survival (OS), and radiological dynamics.

RESULTS

Ten and 15 of 120 patients had a mutation of RAS and PIK3CA in ctDNA, with a positive concordance with tissue deep sequencing of only 31.3% and 47.1%, respectively. Presence of RAS or PIK3CA mutations in baseline ctDNA was associated with worse median PFS [8 vs. 12.8 months; HR, 2.49; 95% confidence interval (CI), 1.28-4.81; P = 0.007 and 8.5 vs. 12.9 months; HR, 2.86; 95% CI, 1.63-5.04; P < 0.001] and median OS (17.1 vs. 36.5 months; HR, 2.26; 95% CI, 1.03-4.96; P = 0.042 and 21.1 vs. 38.9 months; HR, 2.18; 95% CI, 1.16-4.07; P = 0.015). RAS mutations in ctDNA were associated with worse RECIST response, early tumor shrinkage, and depth of response, while PIK3CA mutations were not. Patients with higher levels of RAS/PIK3CA variant allele fraction (VAF) in ctDNA had the worst outcomes (VAF ≥ 5% vs. all wild-type: median PFS, 7.7 vs. 13.1 months; HR, 4.02; 95% CI, 2.03-7.95; P < 0.001 and median OS, 18.8 vs. 38.9 months; HR, 4.07; 95% CI, 2.04-8.12; P < 0.001).

CONCLUSIONS

Baseline ctDNA profiling may add value to tumor tissue testing to refine the molecular hyperselection of patients with mCRC for upfront anti-EGFR-based strategies.

Effects of cabozantinib on bone turnover markers in real-world metastatic renal cell carcinoma

BACKGROUND

Cabozantinib strongly inhibits osteoclast differentiation and bone resorption in vitro. We aimed to evaluate its effect on bone turnover markers (BTMs) in metastatic renal cell carcinoma.

METHODS

This is a monocentric prospective study on patients with mRCC treated with cabozantinib between October 2016 and July 2018. We collected blood samples at baseline and after 3 and 6 months of treatment. We compared sets of data obtained from plasma samples in the whole population with unpaired 2-tailed Student t tests and data for a subset of patients for which all timepoints were available with paired 2-tailed Student t tests. We used the Kaplan-Meier method for survival analyses and the log-rank test to compare the curves.

RESULTS

Our analysis included 39 patients. At month 3, the mean C-terminal cross-linked telopeptides of type I collagen (CTx) and the mean N-terminal propeptide of type 1 collagen (PINP) levels were significantly decreased in the whole population (p = 0.013 and p < 0.0001, respectively), as well as at paired analysis (p = 0.015 and p = 0.045, respectively). No differences were observed between baseline and 6 months (p = 0.053 and p = 0.087, respectively). After 3 months, the mean parathyroid hormone (PTH) levels significantly increased in the whole population (p = 0.004), as well as at paired analysis; the mean PTH levels increased significantly at 3 and 6 months, respectively (p = 0.019 and p = 0.041, respectively). Changes in BTM levels were not associated with outcome.

CONCLUSIONS

Cabozantinib significantly reduced bone resorption as demonstrated by the decrease of CTx and showed a transient secondary increase of PTH.

Prospective Translational Study Investigating Molecular PrEdictors of Resistance to First-Line PazopanIb in Metastatic reNal CEll Carcinoma (PIPELINE Study)

OBJECTIVES

Despite the initial clinical benefit, resistance to antiangiogenic therapies develops through the activation of alternative pathways. We measured plasma levels of circulating angiogenic factors to explore their predictive role in metastatic renal cell carcinoma (mRCC) patients treated with pazopanib.

MATERIALS AND METHODS

mRCC patients receiving first-line pazopanib were prospectively enrolled. The levels of circulating interleuchine (IL)-6, IL-8, stromal derived factor-1, vascular endothelial growth factor-A, hepatocyte growth factor (HGF), osteopontin, and E-selectin were quantified at baseline and every 4 weeks until disease progression (PD). Patients were dichotomized into "low" and "high" subgroups by a cutoff point defined by the respective median circulating angiogenic factor (CAF) value at baseline. Then, association with the objective response was determined. Changes in CAF levels between baseline and PD were also compared.

RESULTS

Among 25 patients included in the final data set, 6 patients were still on treatment. As best response, 12 patients presented a partial response (48%), 9 showed stable disease, and 4 showed PD. The median follow-up was 31.9 months. The median progression-free survival was 14.8 months. Low baseline levels of IL-6, IL-8, HGF, and osteopontin were found to be significantly associated with objective response. In addition, patients with low baseline levels of HGF showed longer progression-free survival and overall survival, whereas patients with low baseline levels of IL-8 showed longer overall survival. Among patients experiencing PD, the median plasma levels of stromal derived factor-1 and vascular endothelial growth factor-A were significantly higher compared with the baseline (P=0.01; P=0.011). Conversely, the median levels of E-selectin were significantly lower compared with the baseline (P=0.017).

CONCLUSION

Changes in levels of selected CAFs were associated with response/resistance to pazopanib in mRCC patients.

Oral maintenance metronomic vinorelbine versus best supportive care in advanced non-small-cell lung cancer after platinum-based chemotherapy: The MA.NI.LA. multicenter, randomized, controlled, phase II trial

BACKGROUND

Oral vinorelbine administered at the maximum tolerated dose has already showed activity and a good safety profile in advanced non-small-cell lung cancer (NSCLC). The MA.NI.LA study was a phase II, multicenter, randomized, controlled trial that aimed to assess the effects of a 'switched maintenance' regimen with oral metronomic vinorelbine (OMV) in patients with NSCLC who had not progressed after first-line platinum-based chemotherapy.

PATIENTS AND METHODS

Patients were randomly assigned in a 1:1 ratio to either OMV (50 mg three-times weekly) as maintenance treatment or best supportive care (BSC). The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective disease control rate (DCR, CR + PR + SD), safety and quality of life.

RESULTS

In total, 61 and 59 patients were assigned to OMV and BSC, respectively. At a median follow-up of 23.9 (IQR 10.2-38.2) months, patients treated with OMV reported a significantly lower progression rate compared to patient in the BSC arm (89% [54/61] vs 96% [56/58]; HR 0.73; 90% CI 0.53-0.999, p = 0.049). Median PFS for patients treated with vinorelbine was 4.3 months (95% CI 2.8-5.6) vs 2.8 months (95% CI 1.9-4.5) for patients receiving BSC. This benefit was specifically evident in patients aged ≥70 years, in current smokers, and in those who reported disease stabilization as best response to induction chemotherapy. OS and response rate and quality of life were similar in the two arms. Drop-out rate for major toxicity with OMV was unexpectedly high (25%, 14/61) mainly due to grade 3-4 neutropenia (11%, 7/61). Conclusions In patients with unselected NSCLC achieving disease control after platinum-based chemotherapy switch maintenance therapy with OMV prolonged PFS compared to BSC; however, the optimal dose of OMV requires further investigation.

Circulating miRNAs and PD-L1 Tumor Expression Are Associated with Survival in Advanced NSCLC Patients Treated with Immunotherapy: a Prospective Study

PURPOSE

Immune-checkpoint inhibitors (ICI) have improved the survival of patients with non-small cell lung cancer (NSCLC). However, only a subset of patients benefit from ICIs, and the role of PD-L1 as predictive biomarker is still debated. A plasma immune-related miRNA-signature classifier (MSC) was established in lung cancer screening settings to identify the lethal form of the disease in early stages. In this exploratory study, we tested the efficacy of the MSC as prognostic marker in patients with advanced NSCLC treated with ICIs.

EXPERIMENTAL DESIGN

The MSC risk level was prospectively assessed in a consecutive series of 140 patients with NSCLC before starting treatment with ICIs. Overall response rate (ORR), progression-free survival (PFS), and overall survival (OS) in strata of PD-L1 and MSC alone or combined were considered as endpoints. Multiple plasma samples to monitor MSC risk level during treatment were also profiled.

RESULTS

Adequate tissue and plasma samples were available from 111 (79%) and 104 (75%) patients with NSCLC, respectively. MSC risk level was associated with ORR (P = 0.0009), PFS [multivariate HR = 0.31; 95% confidence interval (CI), 0.17-0.56; P = 0.0001], and OS (multivariate HR = 0.33; 95% CI, 0.18-0.59; P = 0.0002). The combination of MSC and PD-L1 stratified patients into three risk groups having 39%-18%-0% 1-year PFS (P < 0.0001) and 88%-44%-0% 1-year OS (P < 0.0001), according to the presence of 2-1-0 favorable markers. During treatment, MSC risk level decreased or remained low until tumor progression in patients with responsive or stable disease.

CONCLUSIONS

The plasma MSC test could supplement PD-L1 tumor expression to identify a subgroup of patients with advanced lung cancer with worse ORR, PFS, and OS in immunotherapy regimens.

Early detection of colorectal adenocarcinoma: a clinical decision support tool based on plasma porphyrin accumulation and risk factors

BACKGROUND

An increase in naturally-occurring porphyrins has been described in the blood of subjects bearing different kinds of tumors, including colorectal, and this is probably related to a systemic alteration of heme metabolism induced by tumor cells. The aim of our study was to develop an artificial neural network (ANN) classifier for early detection of colorectal adenocarcinoma based on plasma porphyrin accumulation and risk factors.

METHODS

We measured the endogenous fluorescence of blood plasma in 100 colorectal adenocarcinoma patients and 112 controls using a conventional spectrofluorometer. Height, weight, personal and family medical history, use of alcohol, red meat, vegetables and tobacco were all recorded. An ANN model was built up from demographic data and from the integral of the fluorescence emission peak in the range 610-650 nm. We used the Receiver Operating Characteristic (ROC) curve to assess performance in distinguishing colorectal adenocarcinoma patients and controls. A liquid chromatography-high resolution mass spectrometry (LC-HRMS) analytical method was employed to identify the agents responsible for native fluorescence.

RESULTS

The fluorescence analysis indicated that the integral of the fluorescence emission peak in the range 610-650 nm was significantly higher in colorectal adenocarcinoma patients than controls (p < 0.0001) and was weakly correlated with the TNM staging (Spearman's rho = 0.224, p = 0.011). LC-HRMS measurements showed that the agents responsible for the fluorescence emission were mainly protoporphyrin-IX (PpIX) and coproporphyrin-I (CpI). The overall accuracy of our ANN model was 88% (87% sensitivity and 90% specificity) with an area under the ROC curve of 0.83.

CONCLUSIONS

These results confirm that tumor cells accumulate a diagnostic level of endogenous porphyrin compounds and suggest that plasma porphyrin concentrations, indirectly measured through fluorescence analysis, may be useful, together with risk factors, as a clinical decision support tool for the early detection of colorectal adenocarcinoma. Our future efforts will be aimed at examining how plasma porphyrin accumulation correlates with survival and response to therapy.

Effects of cabozantinib on bone turnover markers in patients with metastatic renal cell carcinoma

638

Background: In-vitro studies have shown that cabozantinib has a strong inhibitory action on osteoclast differentiation and bone-resorption activity. The aim of this analysis was to investigate the effects of cabozantinib on bone turnover markers in patients (pts) with metastatic renal cell carcinoma (mRCC). Methods: We included mRCC pts treated with cabozantinib within the Italian Managed Access Program (MAP) at the Istituto Nazionale Tumori of Milan (Italy). Plasma samples from every patient were collected at baseline and after 3 and 6 months of treatment. The bone resorption markers C-terminal telopeptide of type I collagen (CTx) and tartrate-resistant acid phosphatase isoenzyme 5b (TRACP 5b), the osteoclastogenesis markers osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL), vitamin D and parathormone (PTH) were measured by immunometric assay techniques. Data were analyzed using the RM One-Way ANOVA test with Greenhouse-Geisser correction followed by uncorrected Fisher’s LSD multiple comparison tests with individual variances computed for each comparison. Statistical tests were performed using the program GraphPad Prism (San Diego, CA). Results: Twenty-two pts have been treated with cabozantinib. Mature data were available for 11 pts. Analysis of TRACP 5b, OPG, RANKL and vitamin D did not show any significant variations during treatment with cabozantinib. CTx showed a significant reduction after 6 months of treatment (MV 171.5 pg/mL, STD 208.4) from baseline (mean value [MV] 352.2 pg/mL, standard deviation [STD] 210.1) (p = 0.0439) in the whole study population. PTH levels significantly increased after 3 months of treatment (MV 86.79 pg/mL, STD 34.99) from baseline (MV 30.77 pg/mL, STD 12.64) (p = 0.0003), while significantly decreased after 6 months (MV 75.01 pg/mL, STD 53.1) (p = 0.0174). Conclusions: Our data suggested that cabozantinib significantly reduced bone resorption as demonstrated by the decrease of CTx; it was also associated with an asymptomatic transient secondary increase of parathormone. This is the first clinical evidence on effects of cabozantinib on bone metabolism in a small population of mRCC pts.

Development of a Protocol for Single-Cell Analysis of Circulating Tumor Cells in Patients with Solid Tumors

Genomic characterization of circulating tumor cells (CTCs) enables the monitoring of tumor progression and of adaption occurring during treatment. CTC molecular characterization represents indeed a precious tool to implement in the clinical practice for better dealing with acquired resistance to systemic treatment and tumor evolution. Unfortunately CTCs are very rare and enrichments from blood samples and subsequent identification of these cells are technically very challenging. We describe here the main steps leading to the development of a technical protocol for visualization, enumeration and recovery of single CTCs exploiting the recently developed DEPArray™platform. Our description of the technical workflow starts with evaluation of pre-analytical aspects related to blood sample collection warning about the possible effects on immunoreactivity profiles which may bias the interpretation. Subsequently, other CTC-enrichment approaches are critically discussed and compared in relation to their performances with the DEPArray™. Identification of CTCs represents another critical point due to their heterogeneity and due to the still-to-be clarified role of different subpopulations, typically epithelial, mesenchymal or mixed. Finally, issues related to single cell analysis are illustrated. The chapter ends with an overview of results obtained on real clinical samples which support the reliability of the protocol and its transferability to the daily clinical routine.

Serum soluble urokinase-type plasminogen activator receptor as a serum marker of inflammatory response that leads to tissue damage and surgical complication

Unrestrained activation of the proteolytic systems in anastomotic tissue during repair has been implicated in the pathogenesis of anastomotic leakage. We hypothesized that this mechanism may promote an up-regulation of the urokinase-type plasminogen activator system and a spillover of soluble urokinase-type plasminogen activator receptor (suPAR) into blood. In this retrospective analysis patients with anastomotic leakage were compared with a group of matched uncomplicated patients. Anastomotic leakage complicated patients had significantly higher suPAR (p = 0.04) levels until day 3 after surgery. The area under the receiver-operating characteristic (ROC) for suPAR was higher than that CRP (0.874 vs. 0.836). Their analysis suggests the possible use of suPAR as serum marker to characterize the persistent inflammatory response that lead to tissue damage and surgical complication.

DPD and UGT1A1 deficiency in colorectal cancer patients receiving triplet chemotherapy with fluoropyrimidines, oxaliplatin and irinotecan

AIMS

Triplet chemotherapy with fluoropyrimidines, oxaliplatin and irinotecan is a standard therapy for metastatic colorectal cancer (CRC). Single nucleotide polymorphisms (SNPs) in DPYD and UGT1A1 influence fluoropyrimdines and irinotecan adverse events (AEs). Low frequency DPYD variants (c.1905 + 1G > A, c.1679 T > G, c.2846A > T) are validated but more frequent ones (c.496A > G, c.1129-5923C > G and c.1896 T > C) are not. rs895819 T > C polymorphism in hsa-mir-27a is associated with reduced DPD activity. In this study, we evaluated the clinical usefulness of a pharmacogenetic panel for patients receiving triplet combinations.

METHODS

Germline DNA was available from 64 CRC patients enrolled between 2008 and 2013 in two phase II trials of capecitabine, oxaliplatin and irinotecan plus bevacizumab or cetuximab. SNPs were determined by Real-Time PCR. We evaluated the functional variants in DPYD (rare: c.1905 + 1G > A, c.1679 T > G, c.2846A > T; most common: c.496A > G, c.1129-5923C > G, c.1896 T > C), hsa-mir-27a (rs895819) and UGT1A1 (*28) genes to assess their association with grade 3-4 AEs.

RESULTS

None of the patients carried rare DPYD variants. We found DPYD c.496A > G, c.1129-5923C > G, c.1896 T > C in heterozygosity in 19%, 5% and 8%, respectively, homozygous rs895819 in hsa-mir-27a in 9% and homozygous UGT1A1*28 in 8%. Grade 3-4 AEs were observed in 36% patients and were associated with DPYD c.496A > G (odds ratio (OR) 4.93, 95% CI 1.29, 18.87; P = 0.021) and homozygous rs895819 in hsa-mir-27a (OR 11.11, 95% CI 1.21, 102.09; P = 0.020). Carriers of DPYD c.1896 T > C and homozygous UGT1A1*28 showed an OR of 8.42 (95% CI 0.88, 80.56; P = 0.052). Multivariate analysis confirmed an independent value for DPYD c.496A > G and c.1896 T > C.

CONCLUSIONS

Concomitant assessment of DPYD variants and the UGT1A1*28 allele is a promising strategy needing further validation for dose personalization.

Undetected toxicity risk in pharmacogenetic testing for dihydropyrimidine dehydrogenase

Fluoropyrimidines, the mainstay agents for the treatment of colorectal cancer, alone or as a part of combination therapies, cause severe adverse reactions in about 10%–30% of patients. Dihydropyrimidine dehydrogenase (DPD), a key enzyme in the catabolism of 5-fluorouracil, has been intensively investigated in relation to fluoropyrimidine toxicity, and several DPD gene (DPYD) polymorphisms are associated with decreased enzyme activity and increased risk of fluoropyrimidine-related toxicity. In patients carrying non-functional DPYD variants (c.1905+1G>A, c.1679T>G, c.2846A>T), fluoropyrimidines should be avoided or reduced according to the patients’ homozygous or heterozygous status, respectively. For other common DPYD variants (c.496A>G, c.1129-5923C>G, c.1896T>C), conflicting data are reported and their use in clinical practice still needs to be validated. The high frequency of DPYD polymorphism and the lack of large prospective trials may explain differences in studies’ results. The epigenetic regulation of DPD expression has been recently investigated to explain the variable activity of the enzyme. DPYD promoter methylation and its regulation by microRNAs may affect the toxicity risk of fluoropyrimidines. The studies we reviewed indicate that pharmacogenetic testing is promising to direct personalised dosing of fluoropyrimidines, although further investigations are needed to establish the role of DPD in severe toxicity in patients treated for colorectal cancer.

Circulating tumor cells as a longitudinal biomarker in patients with advanced chemorefractory, RAS-BRAF wild-type colorectal cancer receiving cetuximab or panitumumab

A still relevant number of patients with RAS-BRAF wild-type colorectal cancer (CRC) do not respond to treatment with antiepidermal growth factor receptor (EGFR) monoclonal antibodies cetuximab and panitumumab, suggesting that additional biomarkers to guide patient selection are urgently needed. Circulating tumor cells (CTCs) may represent such a biomarker. In this prospective study, 38 patients with advanced RAS-BRAF-wild-type CRC received third-line therapy with cetuximab-irinotecan or panitumumab. Peripheral blood samples for CTC status determination were collected at baseline, during treatment at early (2-4 weeks) and at later (8-10 weeks) times. CTC enrichment was done with the AdnaTest ColonCancerSelect kit, whereas CTC detection was done with the AdnaTest ColonCancerDetect kit. CTC status positivity was defined according to the kit manufacturer's thresholds. Fifty percent of patients were defined as CTC positive at baseline and the overall RECIST response rate was 26%. CTC baseline status was not associated with treatment response, whereas early CTC status and CTC status changes during treatment were significantly associated with tumor response. Kaplan-Meier analysis showed a significantly shorter progression-free survival (median, 2.0 versus 4.0 months, p = 0.004) and overall survival (4.7 versus11.4, p = 0.039) in patients with early CTC + status compared with CTC - ones. In multivariable analysis including classical prognostic factors, the CTC status changes profile during treatment was an independent predictor of both progression-free survival (p < 0.001) and overall-survival (p = 0.001). CTC status assessed early during treatment with anti-EGFR monoclonal antibodies may predict treatment failure in advance compared to imaging-based tools.

Circulating biomarkers in advanced colorectal cancer patients randomly assigned to three bevacizumab-based regimens

The need to identify biomarkers for bevacizumab-based treatment in advanced colorectal cancer is imperative. The aim of this study was to investigate the prognostic role of circulating VEGF, PDGF, SDF-1, osteopontin and CEA in patients randomly assigned to three bevacizumab-based regimens. Plasma samples from 50 patients treated at a single Institution were analysed using the multiplex assay BioPlex™ 2200 (Bio-Rad Laboratories, Inc, Berkeley, CA, USA) at baseline, before first three cycles and subsequently every three cycles until disease progression. Prognostic analyses of baseline values were performed using multivariable Cox models, including disease extension >10 cm or ≤10 cm (measured as the sum of the diameters for all target lesions) as adjustment factor. The association between progression-free and overall survival and biomarkers modulation during treatment was studied using multivariable Cox models, which included summary statistics synthesizing during-treatment modulation together with disease extension. The biomarkers significantly associated with disease extension were baseline CEA (p = 0.012) and SDF-1 (p = 0.030). High values of VEGF and SDF-1 tended to be associated with worse prognosis, especially in terms of overall survival. The negative prognostic trend was more marked for baseline CEA as compared to other biomarkers; increasing values during treatment was significantly related to worse prognosis independently of disease extension (p = 0.007 and 0.016 for progression-free and overall survival, respectively). VEGF is related to bevacizumab pharmacodynamics and is associated to other angiogenic cytokines; some of the proposed biomarkers such as SDF-1 and CEA should be further validated for prognosis assessment and monitoring of bevacizumab-based treatment of advanced colorectal cancer.

Detection of BRAF and KRAS mutations in DNA released by tumors in peripheral blood by an advanced digital droplet PCR

e22056

Background: Cell-free tumor DNA (cftDNA) is released into the circulation and its recovery from plasma is a non-invasive alternative to tumor biopsy for applications related to molecular profiling. A potential use in therapeutic interventions is the periodic monitoring of cftDNA for the identification of molecular changes associated with resistance to target-specific treatments or when the mutational status in tumor tissue is not available. Methods: Samples (6 ml) of peripheral blood were drawn from patients with colorectal (CRC, n= 19) and thyroid (n= 1) cancers and melanoma (n= 8). CRC tumors were KRAS wild-type (n= 3) or carried the BRAF V600E (n= 6), KRAS G12D (n= 9) and G12V (n= 4) mutations. All melanomas and the thyroid cancer carried the BRAF V600E mutation. DNA was extracted from plasma with QIAamp Circulating Nucleic Acid Kit to recover DNA fragments of ≤1000 bp. PCR amplification was carried out with a QX100 ddPCR System (Bio-Rad) on 20 μL-samples containing cftDNA and TaqMan probes for BRAF V600E (1799T>A), KRAS G12D (35G>A) and G12V (35G>T) labeled with FAM/VIC. Samples were then loaded into a droplet reader, which discriminates the difference in fluorescence amplitudes on the basis of target gene amplification. Results: The concordance between mutations in tumors (T) and plasma (P) for BRAF V600E was: melanomas 8 T vs. 6 P; thyroid cancer 1 T vs. 0 P; CRC 6 T vs 3 P. Concerning KRAS in CRC the results were: G12D 9 T vs. 7 P, G12V 4 T vs. 0 P. Overall, the percentage of concordant samples were: V600E 60%, G12D 77,8%, G12V 0%. Interestingly, in 2 patients with wild-type KRAS tumor, the G12D and G12V mutations were found in plasma. Conclusions: ddPCR is a third-generation PCR technique for highly sensitive detection of DNA fragments. Detection of mutations in cftDNA by advanced technological platforms has important applications in the monitoring of patients for the occurrence of secondary mutations, amplifications and expansion of cell clones that render their tumors resistant to target-specific anticancer agents, unraveling the resistant phenotype before the clinical progression of the disease. Acknowledgments: this study was funded in part by MIUR/PRIN 2011-2012 (Rome, Italy).