Sara Lonardi

Primary Tumor Response to Preoperative Chemoradiation With or Without Oxaliplatin in Locally Advanced Rectal Cancer: Pathologic Results of the STAR-01 Randomized Phase III Trial

PURPOSE To investigate oxaliplatin combined with fluorouracil-based chemoradiotherapy as preoperative treatment for locally advanced rectal cancer. PATIENTS AND METHODS Seven hundred forty-seven patients with resectable, locally advanced (cT3-4 and/or cN1-2) adenocarcinoma of the mid-low rectum were randomly assigned to receive pelvic radiation (50.4 Gy in 28 daily fractions) and concomitant infused fluorouracil (225 mg/m(2)/d) either alone (arm A, n = 379) or combined with oxaliplatin (60 mg/m(2) weekly × 6; arm B, n = 368). Overall survival is the primary end point. A protocol-planned analysis of response to preoperative treatment is reported here. RESULTS Grade 3 to 4 adverse events during preoperative treatment were more frequent with oxaliplatin plus fluorouracil and radiation than with radiation and fluorouracil alone (24% v 8% of treated patients; P < .001). In arm B, 83% of the patients treated with oxaliplatin had five or more weekly administrations. Ninety-one percent, compared with 97% in the control arm, received ≥ 45 Gy (P < .001). Ninety-six percent versus 95% of patients underwent surgery with similar rates of abdominoperineal resections (20% v 18%, arm A v arm B). The rate of pathologic complete responses was 16% in both arms (odds ratio = 0.98; 95% CI, 0.66 to 1.44; P = .904). Twenty-six percent versus 29% of patients had pathologically positive lymph nodes (arm A v arm B; P = .447), 46% versus 44% had tumor infiltration beyond the muscularis propria (P = .701), and 7% versus 4% had positive circumferential resection margins (P = .239). Intra-abdominal metastases were found at surgery in 2.9% versus 0.5% of patients (arm A v arm B; P = .014). CONCLUSION Adding oxaliplatin to fluorouracil-based preoperative chemoradiotherapy significantly increases toxicity without affecting primary tumor response. Longer follow-up is needed to assess the impact on efficacy end points.

Initial Therapy with FOLFOXIRI and Bevacizumab for Metastatic Colorectal Cancer

BACKGROUND A fluoropyrimidine plus irinotecan or oxaliplatin, combined with bevacizumab (a monoclonal antibody against vascular endothelial growth factor), is standard first-line treatment for metastatic colorectal cancer. Before the introduction of bevacizumab, chemotherapy with fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI) showed superior efficacy as compared with fluorouracil, leucovorin, and irinotecan (FOLFIRI). In a phase 2 study, FOLFOXIRI plus bevacizumab showed promising activity and an acceptable rate of adverse effects. METHODS We randomly assigned 508 patients with untreated metastatic colorectal cancer to receive either FOLFIRI plus bevacizumab (control group) or FOLFOXIRI plus bevacizumab (experimental group). Up to 12 cycles of treatment were administered, followed by fluorouracil plus bevacizumab until disease progression. The primary end point was progression-free survival. RESULTS The median progression-free survival was 12.1 months in the experimental group, as compared with 9.7 months in the control group (hazard ratio for progression, 0.75; 95% confidence interval [CI], 0.62 to 0.90; P=0.003). The objective response rate was 65% in the experimental group and 53% in the control group (P=0.006). Overall survival was longer, but not significantly so, in the experimental group (31.0 vs. 25.8 months; hazard ratio for death, 0.79; 95% CI, 0.63 to 1.00; P=0.054). The incidences of grade 3 or 4 neurotoxicity, stomatitis, diarrhea, and neutropenia were significantly higher in the experimental group. CONCLUSIONS FOLFOXIRI plus bevacizumab, as compared with FOLFIRI plus bevacizumab, improved the outcome in patients with metastatic colorectal cancer and increased the incidence of some adverse events. (Funded by the Gruppo Oncologico Nord Ovest and others; ClinicalTrials.gov number, NCT00719797.).

FOLFOXIRI plus bevacizumab versus FOLFIRI plus bevacizumab as first-line treatment of patients with metastatic colorectal cancer: updated overall survival and molecular subgroup analyses of the open-label, phase 3 TRIBE study

BACKGROUND In the TRIBE study, FOLFOXIRI (fluorouracil, leucovorin, oxaliplatin, and irinotecan) plus bevacizumab significantly improved progression-free survival of patients with metastatic colorectal cancer compared with FOLFIRI (fluorouracil, leucovorin, and irinotecan) plus bevacizumab. In this updated analysis, we aimed to provide mature results for overall survival-a secondary endpoint-and report treatment efficacy in RAS and BRAF molecular subgroups. METHODS TRIBE was an open-label, multicentre, phase 3 randomised study of patients (aged 18-70 years with Eastern Cooperative Oncology Group [ECOG] performance status of 2 or less and aged 71-75 years with an ECOG performance status of 0) with unresectable metastatic colorectal cancer who were recruited from 34 Italian oncology units. Patients were randomly assigned (1:1) via a web-based procedure to receive FOLFIRI plus bevacizumab or FOLFOXIRI plus bevacizumab. Bevacizumab was given as a 5 mg/kg intravenous dose. FOLFIRI consisted of a 180 mg/m(2) intravenous infusion of irinotecan for 60 min followed by a 200 mg/m(2) intravenous infusion of leucovorin for 120 min, a 400 mg/m(2) intravenous bolus of fluorouracil, and a 2400 mg/m(2) continuous infusion of fluorouracil for 46 h. FOLFOXIRI consisted of a 165 mg/m(2) intravenous infusion of irinotecan for 60 min, followed by an 85 mg/m(2) intravenous infusion of oxaliplatin given concurrently with 200 mg/m(2) leucovorin for 120 min, followed by a 3200 mg/m(2) continuous infusion of fluorouracil for 48 h. Tissue samples for RAS and BRAF mutational status analyses were centrally collected. In this updated analysis, we assessed the secondary endpoint of overall survival in the main cohort and treatment efficacy in RAS and BRAF molecular subgroups. All analyses were by intention to treat. TRIBE was concluded on Nov 30, 2014. The trial is registered with ClinicalTrials.gov, number NCT00719797. FINDINGS Between July 17, 2008, and May 31, 2011, 508 patients were randomly assigned. At a median follow-up of 48·1 months (IQR 41·7-55·6), median overall survival was 29·8 months (95% CI 26·0-34·3) in the FOLFOXIRI plus bevacizumab group compared with 25·8 months (22·5-29·1) in the FOLFIRI plus bevacizumab group (hazard ratio [HR] 0·80, 95% CI 0·65-0·98; p=0·03). Median overall survival was 37·1 months (95% CI 29·7-42·7) in the RAS and BRAF wild-type subgroup compared with 25·6 months (22·4-28·6) in the RAS-mutation-positive subgroup (HR 1·49, 95% CI 1·11-1·99) and 13·4 months (8·2-24·1) in the BRAF-mutation-positive subgroup (HR 2·79, 95% CI 1·75-4·46; likelihood-ratio test p<0·0001). Treatment effect was not significantly different across molecular subgroups (pinteraction=0·52). INTERPRETATION FOLFOXIRI plus bevacizumab is a feasible treatment option for those patients who meet the inclusion criteria of the present study, irrespective of baseline clinical characteristics and RAS or BRAF mutational status.

Dual-targeted therapy with trastuzumab and lapatinib in treatment-refractory, KRAS codon 12/13 wild-type, HER2-positive metastatic colorectal cancer (HERACLES): a proof-of-concept, multicentre, open-label, phase 2 trial

BACKGROUND We previously found that dual HER2 blockade with trastuzumab and lapatinib led to inhibition of tumour growth in patient-derived xenografts of HER2-amplified metastatic colorectal cancer. In this study, we aimed to assess the antitumour activity of trastuzumab and lapatinib in patients with HER2-positive colorectal cancer. METHODS HERACLES was a proof-of-concept, multicentre, open-label, phase 2 trial done at four Italian academic cancer centres. We enrolled adult patients with KRAS exon 2 (codons 12 and 13) wild-type and HER2-positive metastatic colorectal cancer refractory to standard of care (including cetuximab or panitumumab), an Eastern Cooperative Oncology Group performance status of 0 or 1, and at least one measurable lesion. We defined HER2 positivity in tumour samples by use of immunohistochemistry and fluorescence in-situ hybridisation in accordance with our previously validated colorectal cancer-specific diagnostic criteria. Eligible patients received intravenous trastuzumab at 4 mg/kg loading dose followed by 2 mg/kg once per week, and oral lapatinib at 1000 mg per day until evidence of disease progression. The primary endpoint was the proportion of patients achieving an objective response (defined as complete response or partial response), which was assessed by independent central review in the intention-to-treat population. This trial is registered with EudraCT, number 2012-002128-33. FINDINGS Between Aug 27, 2012, and May 15, 2015, we screened 914 patients with KRAS exon 2 (codons 12 and 13) wild-type metastatic colorectal cancer and identified 48 (5%) patients with HER2-positive tumours, although two died before enrolment. Of these patients, 27 were eligible for the trial. All were evaluable for response. At the time of data cutoff on Oct 15, 2015, with a median follow-up of 94 weeks (IQR 51-127), eight (30%, 95% CI 14-50) of 27 patients had achieved an objective response, with one patient (4%, 95% CI -3 to 11) achieving a complete response, and seven (26%, 95% CI 9-43) achieving partial responses; 12 (44%, 95% CI 25-63) patients had stable disease. Six (22%) of 27 patients had grade 3 adverse events, which consisted of fatigue in four patients, skin rash in one patient, and increased bilirubin concentration in one patient. No grade 4 or 5 adverse events were reported. We detected no drug-related serious adverse events. INTERPRETATION The combination of trastuzumab and lapatinib is active and well tolerated in treatment-refractory patients with HER2-positive metastatic colorectal cancer. FUNDING Associazione Italiana Ricerca Cancro (AIRC), Fondazione Oncologia Niguarda Onlus, and Roche.

Nivolumab in patients with metastatic DNA mismatch repair-deficient or microsatellite instability-high colorectal cancer (CheckMate 142): an open-label, multicentre, phase 2 study

BACKGROUND Metastatic DNA mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) colorectal cancer has a poor prognosis after treatment with conventional chemotherapy and exhibits high levels of tumour neoantigens, tumour-infiltrating lymphocytes, and checkpoint regulators. All of these features are associated with the response to PD-1 blockade in other tumour types. Therefore, we aimed to study nivolumab, a PD-1 immune checkpoint inhibitor, in patients with dMMR/MSI-H metastatic colorectal cancer. METHODS In this ongoing, multicentre, open-label, phase 2 trial, we enrolled adults (aged ≥18 years) with histologically confirmed recurrent or metastatic colorectal cancer locally assessed as dMMR/MSI-H from 31 sites (academic centres and hospitals) in eight countries (Australia, Belgium, Canada, France, Ireland, Italy, Spain, and the USA). Eligible patients had progressed on or after, or been intolerant of, at least one previous line of treatment, including a fluoropyrimidine and oxaliplatin or irinotecan. Patients were given 3 mg/kg nivolumab every 2 weeks until disease progression, death, unacceptable toxic effects, or withdrawal from study. The primary endpoint was investigator-assessed objective response as per Response Evaluation Criteria in Solid Tumors (version 1.1). All patients who received at least one dose of study drug were included in all analyses. This trial is registered with ClinicalTrials.gov, number NCT02060188. FINDINGS Of the 74 patients who were enrolled between March 12, 2014, and March 16, 2016, 40 (54%) had received three or more previous treatments. At a median follow-up of 12·0 months (IQR 8·6-18·0), 23 (31·1%, 95% CI 20·8-42·9) of 74 patients achieved an investigator-assessed objective response and 51 (69%, 57-79) patients had disease control for 12 weeks or longer. Median duration of response was not yet reached; all responders were alive, and eight had responses lasting 12 months or longer (Kaplan-Meier 12-month estimate 86%, 95% CI 62-95). The most common grade 3 or 4 drug-related adverse events were increased concentrations of lipase (six [8%]) and amylase (two [3%]). 23 (31%) patients died during the study; none of these deaths were deemed to be treatment related by the investigator. INTERPRETATION Nivolumab provided durable responses and disease control in pre-treated patients with dMMR/MSI-H metastatic colorectal cancer, and could be a new treatment option for these patients. FUNDING Bristol-Myers Squibb.

Preoperative fluorouracil (FU)-based chemoradiation with and without weekly oxaliplatin in locally advanced rectal cancer: Pathologic response analysis of the Studio Terapia Adiuvante Retto (STAR)-01 randomized phase III trial

CRA4008 Background: Oxaliplatin (OXA) enhances the efficacy of FU-based chemotherapy in colon cancer. This randomized phase III trial investigated the effect of adding OXA to preoperative (preop) FU-based pelvic chemoradiation (CRT) in patients (pts) with locally-advanced rectal cancer. METHODS Eligibility required a resectable, biopsy-proven rectal adenocarcinoma within 12 cm from the anal verge with radiological evidence of perirectal fat or lymphnode involvement. Randomization was between infused FU (225 mg/msq/day) concomitant to external-beam pelvic radiation (50.4 Gy in 28 daily fractions) (arm A) or the same regimen + weekly OXA (60 mg/msq × 6) (Arm B). Surgery was scheduled 6-8 weeks after completing CRT. Overall survival was the primary endpoint. A protocol-planned analysis of local tumor response to preop treatment (secondary end-point) is the object of this report. RESULTS 747 pts from 41 Italian centers were randomized between 12/2003 and 8/2008 (arm A/B: 379/368). Pretreatment characteristics in arm A/B: median age 63/62 years; male:female 2:1; median distance from anal verge 6 cm; T4 16/14%, N+ 63/65%. Overall grade 3-4 toxicity rates on treated pts (mainly diarrhoea) were 8% and 24% (arm A/B, p<0.001). 96/90% of pts (arm A/B) received > 90% of the planned RT. 82% of Arm B pts had > 5 oxa courses. 358/342 pts (arm A/B) had surgery at a median of 52/53 days from the end of CRT, 14 pts in each arm were not operated (progression 8, death 5, other/unknown 15) and surgery data are not yet available for 19 pts. Pathologic response data analyzed on the randomized population are reported in the table . CONCLUSIONS The addition of weekly OXA to standard FU-based preop CRT significantly increases toxicity without affecting local tumor response. The reduced pathologic M+ rate suggests a potential effect on distant micrometastases. Longer follow-up is needed to assess the impact on efficacy endpoints. [Table: see text] No significant financial relationships to disclose.

FOLFOXIRI plus bevacizumab as first-line treatment in BRAF mutant metastatic colorectal cancer

BACKGROUND BRAF V600E mutation plays a negative prognostic role in metastatic colorectal cancer (mCRC), leading to a median Progression Free Survival (PFS) of 4-6months with first-line conventional treatments. Our group recently reported in a retrospective exploratory analysis of a phase II trial that FOLFOXIRI (5-FU/LV+Oxaliplatin+Irinotecan) plus bevacizumab might allow to achieve remarkable results in terms of PFS and Overall Survival (OS) also in this poor-prognosis subgroup. The aim of this work was to prospectively validate our retrospective finding. PATIENTS AND METHODS This phase II trial was designed to detect an increase in 6month-Progression Free Rate (6m-PFR) from 45% to 80% in a population of BRAF mutant mCRC patients treated with first-line FOLFOXIRI plus bevacizumab. Secondary end-points were PFS, OS, response rate (RR) and the analysis of outcome parameters in the pooled population consisting of both retrospectively and prospectively included patients. This trial is registered with ClinicalTrials.gov, number NCT01437618. RESULTS Two-hundred-fourteen potentially eligible mCRC patients were screened for BRAF mutational status. Fifteen BRAF mutant patients (7%) were included in the validation cohort. At a median follow up of 25.7months, 6m-PFR was 73%. Median PFS and OS were 9.2 and 24.1months, respectively. In the pooled population, at a median follow up of 40.4months, 6m-PFR was 84%. Median PFS and OS were 11.8 and 24.1months, respectively. Overall RR and disease control rate were 72% and 88%, respectively. CONCLUSION Lacking randomised trials in this specific molecular subgroup, FOLFOXIRI plus bevacizumab might be a reasonable option for the first-line treatment of BRAF mutant mCRC patients.

Intermittent versus continuous chemotherapy in advanced colorectal cancer: a randomised ‘GISCAD’ trial

BACKGROUND In advanced colorectal cancer, chemotherapy is usually administered without pauses and until progression but patients can experience cumulative toxicity and cannot tolerate a heavy therapeutic charge. AIM The aim of the present trial was to evaluate whether an intermittent chemotherapy with levo-leucovorin + 5-fluorouracil (5-FU) + irinotecan (CPT-11) was at least as effective as the same regimen given continuously, both administered until progression, in patients affected with advanced colorectal cancer and not previously exposed to chemotherapy for metastatic disease. PATIENTS, MATERIALS AND METHODS A total of 337 patients from 27 institutions were randomised between levo-leucovorin, 100/mg/m(2) i.v. + 5-FU; 400 mg/m(2) i.v. bolus + 5-FU; 600 mg/m(2) 22-h continuous infusion, days 1 and 2 + CPT-11; 180 mg/m(2) day 1, administered every 2 weeks 2 months on and 2 months off (arm A) and the same regimen administered continuously (arm B), until progression in both arms. The main end point was overall survival (OS), the secondary progression-free survival (PFS) and toxicity. RESULTS At a median follow-up of 41 months, OS was 18 months in arm A and 17 months in arm B [hazard ratio (HR), 0.88]. Also PFS was comparable in the two groups (6 months in both, with HR, 1.03), and even grades 3-4 toxicity (mainly myelosuppression, fever and diarrhoea) was similar. Second-line oxaliplatin-based treatment was administered in a similar percentage (66%) in the two arms. The median chemotherapy-free period (drug holiday) in arm A was 3.5 months. CONCLUSION Reducing the charge of therapy in this population did not diminish the efficacy of treatment. Further studies with this strategy, including biologicals, are warranted.

BRAF codons 594 and 596 mutations identify a new molecular subtype of metastatic colorectal cancer at favorable prognosis

BACKGROUND While the negative prognostic role of BRAF V600E mutation in metastatic colorectal cancer (mCRC) is well established, the impact of BRAF codons 594 and 596 mutations, occurring in <1% of CRCs, is completely unknown. The present work aims to describe clinical, pathological and molecular features and prognosis of BRAF codons 594 and 596 mutant mCRCs, compared with BRAF V600E mutant and wild-type ones. PATIENTS AND METHODS Patients treated for mCRC at three Italian Institutions between October 2006 and October 2014, with available KRAS and NRAS codon 12, 13, 59, 61, 117 and 146 and BRAF codon 594, 596 and 600 mutational status, as detected by means of direct sequencing or matrix assisted laser desorption ionization time-of-flight MassArray, were included. RESULTS Ten patients bearing BRAF codons 594 or 596 mutated tumors were identified and compared with 77 and 542 patients bearing BRAF V600E mutated and BRAF wild-type tumors, respectively. While BRAF V600E mutated tumors were more frequently right-sided, mucinous and with peritoneal spread, BRAF 594 or 596 mutated were more frequently rectal, nonmucinous and with no peritoneal spread. All BRAF 594 or 596 mutated tumors were microsatellite stable. Patients with BRAF codons 594 or 596 mutated tumors had markedly longer overall survival (OS) when compared with BRAF V600E mutated [median OS: 62.0 versus 12.6 months; hazard ratio: 0.36 (95% confidence interval 0.20-0.64), P = 0.002], both at univariate and multivariate analyses. CONCLUSIONS BRAF codon 594 or 596 mutated mCRCs are different from BRAF V600E ones in terms of molecular features, pathological characteristics and clinical outcome. This is consistent with preclinical evidences of a kinase inactivating effect of these mutations. The role of CRAF in transducing the intracellular signal downstream BRAF 594 or 596 mutated proteins opens the way to further preclinical investigation.

FOLFOXIRI in combination with panitumumab as first-line treatment in quadruple wild-type (KRAS, NRAS, HRAS, BRAF) metastatic colorectal cancer patients: a phase II trial by the Gruppo Oncologico Nord Ovest (GONO)

BACKGROUND The FOLFOXIRI regimen developed by the Gruppo Oncologico Nord Ovest (GONO) demonstrated higher activity and efficacy compared with FOLFIRI in metastatic colorectal cancer (mCRC). Panitumumab is effective in some patients with KRAS codon 12-13 wild-type mCRC. KRAS codon 61, HRAS, NRAS, and BRAF V600E mutations might predict resistance to anti-epidermal growth factor receptor antibodies. PATIENTS AND METHODS We conducted a phase II study evaluating the combination of panitumumab (6 mg/kg on day 1) with a slightly modified GONO-FOLFOXIRI (irinotecan 150 mg/m², oxaliplatin 85 mg/m², and folinate 200 mg/m² on day 1, followed by fluorouracil 3000 mg/m² as a 48-h continuous infusion starting on day 1) repeated every 2 weeks as first-line treatment of wild-type KRAS, HRAS, NRAS (codon 12-13-61), and BRAF unresectable mCRC patients. Fluorouracil dose was reduced to 2400 mg/m² after two of the first three patients reported grade 3-4 diarrhoea (in one case with febrile neutropenia). Induction treatment was scheduled for a maximum of 12 cycles, followed by panitumumab ± fluorouracil/folinate maintenance until progression. Primary end point was overall response rate (ORR). RESULTS Eighty-seven patients were screened and 37 were enrolled. Thirty-three patients achieved an objective response (ORR: 89%; 95% CI 75% to 96%). Sixteen patients (43%) underwent secondary surgery of metastases, and R0 resection was achieved in 13 cases (35%). At a median follow-up of 17.7 months, median progression-free survival was 11.3 months (95% CI 9.7-12.9 months). After amendment, most common grade 3-4 adverse events reported during induction treatment were neutropenia (48%; febrile neutropenia: 5%), diarrhoea (35%), asthenia (27%), stomatitis (14%), and skin toxic effect (14%). One treatment-related death was registered. CONCLUSIONS Adding panitumumab to FOLFOXIRI is feasible decreasing the dose of fluorouracil and irinotecan to reduce the risk of diarrhoea. Activity and secondary resectability of metastases among Ras-BRAF wild-type patients are promising.