Giovanni Fucà

Emergence of MET hyper-amplification at progression to MET and BRAF inhibition in colorectal cancer

Background:Combined MET and BRAF inhibition showed clinical benefit in a patient with rectal cancer carrying BRAFV600E and MET amplification. However after 4 months, acquired resistance emerged and the patient deceased shortly after disease progression. The mechanism of resistance to this drug combination is unknown.Methods:We analysed plasma circulating tumour DNA obtained at progression by exome sequencing and digital PCR. MET gene and mRNA in situ hybridisation analyses in two bioptic specimens obtained at progression were used to confirm the plasma data.Results:We identified in plasma MET gene hyper-amplification as a potential mechanism underlying therapy resistance. Increased MET gene copy and transcript levels were detected in liver and lymph node metastatic biopsies. Finally, transduction of MET in BRAF mutant colorectal cancer cells conferred refractoriness to BRAF and MET inhibition.Conclusions:We identified in a rectal cancer patient MET gene hyper-amplification as mechanism of resistance to dual BRAF and MET inhibition.

Negative hyper-selection of metastatic colorectal cancer patients for anti-EGFR monoclonal antibodies: The PRESSING case-control study

Background Refining the selection of metastatic colorectal cancer patients candidates for anti-epidermal growth factor receptor (EGFR) monoclonal antibodies beyond RAS and BRAF testing is a challenge of precision oncology. Several uncommon genomic mechanisms of primary resistance, leading to activation of tyrosine kinase receptors other than EGFR or downstream signalling pathways, have been suggested by preclinical and retrospective studies. Patients and methods We conducted this multicentre, prospective, case-control study to demonstrate the negative predictive impact of a panel of rare genomic alterations [PRESSING (PRimary rESiStance IN RAS and BRAF wild-type metastatic colorectal cancer patients treated with anti-eGfr monoclonal antibodies) panel], including HER2/MET amplifications, ALK/ROS1/NTRK1-3/RET fusions and PIK3CA mutations. Hypothesizing a prevalence of candidate alterations of 15% and 0% in resistant and sensitive RAS and BRAF wild-type patients, respectively, with two-sided α and β errors of 0.05 and 0.20, 47 patients per group were needed. Results Forty-seven patients per group were included. PRESSING panel alterations were significantly more frequent in resistant (24 out of 47, 51.1%) than in sensitive (1 out of 47, 2.1%) patients (P < 0.001) and in right- (12 out of 29, 41.4%) than left-sided (13 out of 65, 20.0%) tumours (P = 0.03). The predictive accuracy of PRESSING panel and sidedness was 75.3% and 70.2%, respectively. Among hyper-selected patients, right-sidedness was still associated with resistance (P = 0.002). The predictive accuracy of the combined evaluation of PRESSING panel and sidedness was 80.4%. As a secondary analysis, 8 (17.0%) resistant and 0 sensitive patients showed microsatellite instability (P < 0.001). Conclusion The investigated panel of genomic alterations allows refining the selection of RAS and BRAF wild-type metastatic colorectal cancer patients candidates for anti-EGFRs, partially explaining and further corroborating the predictive ability of primary tumour sidedness.

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

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

RET fusions in a small subset of advanced colorectal cancers at risk of being neglected

Background Recognition of rare molecular subgroups is a challenge for precision oncology and may lead to tissue-agnostic approval of targeted agents. Here we aimed to comprehensively characterize the clinical, pathological and molecular landscape of RET rearranged metastatic colorectal cancer (mCRC). Patients and methods In this case series, we compared clinical, pathological and molecular characteristics of 24 RET rearranged mCRC patients with those of a control group of 291 patients with RET negative tumors. RET rearranged and RET negative mCRCs were retrieved by systematic literature review and by taking advantage of three screening sources: (i) Ignytas phase 1/1b study on RXDX-105 (NCT01877811), (ii) cohorts screened at two Italian and one South Korean Institutions and (iii) Foundation Medicine Inc. database. Next-generation sequencing data were analyzed for RET rearranged cases. Results RET fusions were more frequent in older patients (median age of 66 versus 60 years, P = 0.052), with ECOG PS 1-2 (90% versus 50%, P = 0.02), right-sided (55% versus 32%, P = 0.013), previously unresected primary tumors (58% versus 21%, P < 0.001), RAS and BRAF wild-type (100% versus 40%, P < 0.001) and MSI-high (48% versus 7%, P < 0.001). Notably, 11 (26%) out of 43 patients with right-sided, RAS and BRAF wild-type tumors harbored a RET rearrangement. At a median follow-up of 45.8 months, patients with RET fusion-positive tumors showed a significantly worse OS when compared with RET-negative ones (median OS 14.0 versus 38.0 months, HR: 4.59; 95% CI, 3.64-32.66; P < 0.001). In the multivariable model, RET rearrangements were still associated with shorter OS (HR: 2.97; 95% CI, 1.25-7.07; P = 0.014), while primary tumor location, RAS and BRAF mutations and MSI status were not. Conclusions Though very rare, RET rearrangements define a new subtype of mCRC that shows poor prognosis with conventional treatments and is therefore worth of a specific management.

Identification and characterization of a novel SCYL3-NTRK1 rearrangement in a colorectal cancer patient

In colorectal cancer patients, chromosomal rearrangements involving NTRK1 gene (encoding the TRKA protein) are shown in a small subset of patients and are associated with the constitutive activation of the kinase domain of TRKA. In turn, activated TRKA-fusion proteins are associated with proliferation and survival in colorectal cancer tumors. Here we report the identification and functional characterization of a new SCYL3-NTRK1 fusion gene in a 61-year-old colorectal cancer patient. To our knowledge, this fusion protein has never been previously documented in oncological patients. We show that this novel fusion is oncogenic and sensitive to TRKA inhibitors. As suggested by other pieces of evidence, entrectinib - an orally available pan-TRK, ROS1 and ALK inhibitor - may have particular efficacy in patients with NTRK rearrangements. Therefore, screening for rearrangements involving NTRK genes may help identifying a subset of patients able to derive benefit from treatment with entrectinib or other targeted inhibitors.In colorectal cancer patients, chromosomal rearrangements involving NTRK1 gene (encoding the TRKA protein) are shown in a small subset of patients and are associated with the constitutive activation of the kinase domain of TRKA. In turn, activated TRKA-fusion proteins are associated with proliferation and survival in colorectal cancer tumors.Here we report the identification and functional characterization of a new SCYL3-NTRK1 fusion gene in a 61-year-old colorectal cancer patient. To our knowledge, this fusion protein has never been previously documented in oncological patients. We show that this novel fusion is oncogenic and sensitive to TRKA inhibitors.As suggested by other pieces of evidence, entrectinib - an orally available pan-TRK, ROS1 and ALK inhibitor - may have particular efficacy in patients with NTRK rearrangements. Therefore, screening for rearrangements involving NTRK genes may help identifying a subset of patients able to derive benefit from treatment with entrectinib or other targeted inhibitors.

Exposure to multiple lines of treatment and survival of patients with metastatic renal cell carcinoma: a real-world analysis.

Micro‐Abstract The aim of the present retrospective analysis was to describe trends in exposure to multiple lines of treatment and survival among 500 metastatic renal cell carcinoma patients who started first‐line therapy in 2 different periods (2004‐2010 and 2011‐2017) in daily practice. Patients who started treatment during the past 5 years received a greater number of treatment lines with an improvement in overall survival. Background: The purpose of the present retrospective analysis was to describe the trends in exposure to multiple lines of treatment and overall survival (OS) in patients with metastatic renal cell carcinoma (mRCC) who started therapy in 2 different periods (period 1, 2004‐2010; and period 2, 2011‐2017). Patients and Methods: The proportion of patients who received subsequent lines of treatment after disease progression was compared between the 2 groups. OS was measured from the start of first‐line treatment for metastatic disease to death or the last follow‐up examination. Both univariate and multivariate analyses were performed. Results: A total of 500 patients were included in the study; 274 started treatment in period 1 and 226 in period 2. Of those patients who stopped first‐line treatment because of disease progression, the patients in period 2 had a greater conditional probability to receive second‐ and third‐line treatment compared with patients in period 1 (77.2% vs. 63.7%; odds ratio [OR], 1.93; 95% confidence interval [CI], 1.20‐3.11; P = .0065; and 69.6% vs. 48.1%; OR, 2.48; 95% CI, 1.40‐4.40; P = .002, respectively). The median OS improved from 22.8 months for patients in period 1 to 38.2 months for patients in period 2 (univariate analysis: hazard ratio, 0.65; 95% CI, 0.50‐0.83; P = .001). Conclusion: Patients who started treatment during the past 5 years were exposed to a greater number of treatment lines compared with patients treated before 2011. Our data suggest that the increase of treatment options available and clinician expertise could be associated with better outcomes.

Multimodal treatment of advanced renal cancer in 2017

ABSTRACT Introduction: in the last decades, the treatment of renal cell carcinoma has become more complex due to the introduction of novel systemic agents and the improvement of the loco-regional therapies that prolong survival maintaining a good quality of life. Areas covered: in this review, we summarize the currently available local and systemic treatment options, their indications and their hypothetical role in the management of advanced renal cell carcinoma, highlighting the need of multimodality treatment paradigms within interdisciplinary decision-making. Expert commentary: in early disease, radical or partial nephrectomy remains the standard of care, but innovative ablation techniques, including radiofrequency ablation, microwave ablation, cryoablation and so on, may represent an alternative option of treatment for small renal lesions in unfit patients who cannot undergo surgery. In metastatic setting, it is imperative a multidisciplinary team approach to select patients for a cytoreductive nephrectomy, metastasectomy, and/or systemic treatment, aiming to the optimization of the treatment strategy.

TARIBO trial: targeted therapy with or without nephrectomy in metastatic renal cell carcinoma: liquid biopsy for biomarkers discovery

Purpose: Two randomized trials in the cytokine era showed that cytoreductive nephrectomy (CN) had a role in metastatic renal cell carcinoma (mRCC), increasing life expectancy. The survival benefit of tyrosine kinase inhibitors (TKIs), including first-line sunitinib and pazopanib, in mRCC has been demonstrated, but the majority of patients enrolled in the pivotal phase III studies had undergone nephrectomy. Therefore it is unknown if similar survival benefit with targeted agents could be achieved without CN. We hypothesize that in these patients CN could increase overall survival (OS) in comparison to targeted therapy without CN. We also will investigate mechanisms of primary and secondary resistance to TKIs in patients with mRCC and identify prognostic or predictive biomarkers. Methods: This is a randomized, open-label, controlled, multicenter phase 3 study comparing sunitinib or pazopanib vs CN followed by sunitinib or pazopanib as first-line therapy for patients with mRCC who have not received surgery and prior systemic treatment for metastatic disease. We will identify 270 patients eligible for randomization. The planned treatment duration per patient will be until progressive disease is observed. Secondary endpoints are the evaluation of progression-free survival (PFS) and response rate and the assessment of the safety profile. Exploratory objectives include the evaluation of circulating tumor cells and circulating tumor DNA and correlation with response/resistance to treatment. Results: The study is enrolling patients. Conclusions: The use of CN in addition to targeted therapy in patients with renal cell carcinoma with synchronous metastases could lead to a significant improvement in OS and PFS.

Preoperative Capecitabine, Oxaliplatin, and Irinotecan in Resectable Gastric or Gastroesophageal Junction Cancer: Pathological Response as Primary Endpoint and FDG-PET Predictions

Objectives: This phase II trial was aimed at assessing the safety and activity of capecitabine, oxaliplatin, and irinotecan (COI regimen) as a preoperative treatment for resectable gastric cancer (GC) or gastroesophageal junction (GEJ) cancer. Methods: Patients affected by T3-T4/N0-N+/M0 GC/GEJ cancer were treated with the COI regimen for 4 cycles followed by restaging and gastroresection with D2 lymphadenectomy. Four postoperative cycles were scheduled. The primary endpoint was pathological response rate according to Becker et al. [Cancer 2003;98:1521-1530]. The potential role of fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) as a predictive biomarker of pathological tumor response was assessed in a subgroup of 19 evaluable patients. Results: Between January 2011 and October 2015, a total of 40 patients were enrolled. After the preoperative phase, 36 out of 40 patients (90%) were considered eligible for surgery: 12 patients (30%) achieved a pathological response. The most frequent grade 3/4 adverse events were diarrhea (27%), nausea (25%), and fatigue (17%). Grade 3 neutropenia occurred in 7.5% of patients. A lower standard uptake value at baseline FDG-PET/CT was associated with pathological response. Conclusion: COI combination is active with a manageable toxicity profile in patients with resectable GC or GEJ cancer. FDG-PET/CT imaging as a surrogate biomarker of pathological response in this setting appears fascinating but should be further investigated.

Abstract LB-238: Dissecting primary resistance to anti-EGFR monoclonal antibodies (anti-EGFRs) inRASandBRAFwild-type (wt) metastatic colorectal cancer (mCRC)

Patients with RAS and BRAF wt mCRC are regarded as the best candidates to receive anti-EGFRs. Nevertheless, almost half of these patients do not achieve response, so that a deeper refinement of candidates’ selection would be highly desirable. Different molecular alterations, supported by a strong and sound biologic rationale, have been suggested as predictors of primary resistance to anti-EGFRs, but up today their potential impact has been suggested only in preclinical experiences and retrospective series, and their low frequency makes difficult the validation of each single marker. The present case-control study was conducted to prospectively demonstrate the negative predictive impact of HER-2 amplification or mutations, MET amplification, NTRK/ROS1/ALK/RET rearrangements, and mutations activating MAPKs or PI3K/Akt axis. Patients with RAS and BRAF wt mCRC clearly resistant (cases) vs. clearly sensitive (controls) to single-agent anti-EGFRs were selected, their archival tissue samples were collected and the prevalence of above-mentioned alterations was prospectively assessed. HER-2 status was evaluated by immunohistochemistry (IHC) and silver in-situ hybridization (SISH); MET amplification was studied by SISH; gene rearrangements were screened by IHC followed by RNA-based NGS confirmation. Other candidate mutations were investigated by NGS (Hotspot Cancer Panel v2, Ion Torrent Personal Genome platform (Life Technologies®). Hypothesizing a prevalence of candidate alterations of 0% and 15% among controls and cases, respectively, we needed to include 47 cases and 47 controls to be able to reject the null hypothesis that the prevalence of alterations is equal, with α-error 0.05 and β-error 0.20. Moreover, we evaluated the predictive impact of microsatellite instability, since hypermutated tumors may hardly rely on a single pathway (i.e. EGFR) for their growth. Forty-six cases and 47 controls were included. The primary endpoint was met: above-mentioned alterations were reported in 19 (41.3%) cases and 1 (2.1%) control (p This is the first prospective demonstration that the combined assessment of these rare alterations allows to better select patients for treatment with anti-EGFRs, while opening the way to properly tailored therapies. Citation Format: Chiara Cremolini, Rosa Berenato, Federica Morano, Roberto Moretto, Federica Perrone, Elena Tamborini, Daniele Rossini, Annunziata Gloghini, Adele Busico, Giovanni Fuca, Chiara Baratelli, Emiliano Tamburini, Iolanda Capone, Chiara Costanza Volpi, Massimo Milione, Massimo Di Maio, Gabriella Fontanini, Filippo De Braud, Alfredo Falcone, Filippo Pietrantonio. Dissecting primary resistance to anti-EGFR monoclonal antibodies (anti-EGFRs) in RAS and BRAF wild-type (wt) metastatic colorectal cancer (mCRC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-238. doi:10.1158/1538-7445.AM2017-LB-238