Activating mutations in downstream genes of the epidermal growth factor receptor (EGFR) pathway may cause anti-EGFR resistance in patients with colorectal cancers. We present performance ...characteristics of a next-generation sequencing assay designed to detect such mutations. In this retrospective quality assessment study, we analyzed mutation detected in the KRAS, NRAS, BRAF, and PIK3CA genes by a clinically validated next-generation sequencing assay in 310 colorectal cancer specimens. Tumor cellularity and mutant allele frequency were analyzed to identify tumor heterogeneity and mutant allele-specific imbalance. Next-generation sequencing showed precise measurement of mutant allele frequencies and detected 23% of mutations with 2-20% mutant allele frequencies. Of the KRAS mutations detected, 17% were outside of codons 12 and 13. Among PIK3CA mutations, 48% were outside of codons 542, 545, and 1047. The percentage of tumors with predicted resistance to anti-EGFR therapy increased from 40% when testing for only mutations in KRAS exon 2 to 47% when testing for KRAS exons 2-4, 48% when testing for KRAS and NRAS exons 2-4, 58% when including BRAF codon 600 mutations, and 59% when adding PIK3CA exon 20 mutations. Right-sided colorectal cancers carried a higher risk of predicted anti-EGFR resistance. A concomitant KRAS mutation was detected in 51% of PIK3CA, 23% of NRAS, and 33% of kinase-impaired BRAF-mutated tumors. Lower than expected mutant allele frequency indicated tumor heterogeneity, while higher than expected mutant allele frequency indicated mutant allele-specific imbalance. Two paired neuroendocrine carcinomas and adjacent adenomas showed identical KRAS mutations, but only PIK3CA mutations in neuroendocrine carcinomas. Next-generation sequencing is a robust tool for mutation detection in clinical laboratories. It demonstrates high analytic sensitivity and broad reportable range, and it provides simultaneous detection of concomitant mutations and a quantitative measurement of mutant allele frequencies to predict tumor heterogeneity and mutant allele-specific imbalance.
DNA methyltransferase inhibitors (DNMTi) have demonstrated benefit in reversing resistance to systemic therapies for several cancer types. In a phase II trial of guadecitabine and irinotecan compared ...to regorafenib or TAS-102 in pts with advanced mCRC refractory to irinotecan. Patients with mCRC refractory to irinotecan were randomized 2:1 to guadecitabine and irinotecan (Arm A) vs standard of care regorafenib or TAS-102 (Arm B) on a 28-day cycle. Between January 15, 2016 and October 24, 2018, 104 pts were randomized at four international sites, with 96 pts undergoing treatment, 62 in Arm A and 34 in Arm B. Median overall survival was 7.15 months for Arm A and 7.66 months for Arm B (HR 0.93, 95% CI: 0.58-1.47, P = .75). The Kaplan-Meier rates of progression free survival at 4 months were 32% in Arm A and 26% in Arm B. Common ≥Grade 3 treatment related adverse events in Arm A were neutropenia (42%), anemia (18%), diarrhea (11%), compared to Arm B pts with neutropenia (12%), anemia (12%). Guadecitabine and irinotecan had similar OS compared to standard of care TAS-102 or regorafenib, with evidence of target modulation. Clinical trial information: NCT01896856.
Cholangiocarcinoma is an aggressive malignancy with limited therapeutic options. MEK inhibition and antiangiogenic therapies have individually shown modest activity in advanced cholangiocarcinoma, ...whereas dual inhibition of these pathways has not been previously evaluated. We evaluated the safety and efficacy of combination therapy with the oral VEGF receptor tyrosine kinase inhibitor pazopanib plus the MEK inhibitor trametinib in patients with advanced cholangiocarcinoma.
In this open-label, multicentre, single-arm trial, adults with advanced unresectable cholangiocarcinoma received pazopanib 800 mg daily and trametinib 2 mg daily until disease progression or unacceptable toxicity. The primary end point was progression-free survival (PFS) with secondary end points including overall survival (OS), response rate, and disease control rate (DCR).
A total of 25 patients were enrolled and had received a median of 2 prior systemic therapies (range 1-7). Median PFS was 3.6 months (95% CI: 2.7-5.1) and the 4-month PFS was 40% (95% CI: 24.7-64.6%). There was a trend towards increased 4-month PFS as compared with the prespecified null hypothesised 4-month PFS of 25%, but this difference did not reach statistical significance (P=0.063). The median survival was 6.4 months (95% CI: 4.3-10.2). The objective response rate was 5% (95% CI: 0.13-24.9%) and the DCR was 75% (95% CI: 51%, 91%). Grade 3/4 adverse events attributable to study drugs were observed in 14 (56%) and included thrombocytopenia, abnormal liver enzymes, rash, and hypertension.
Although the combination of pazopanib plus trametinib had acceptable toxicity with evidence of clinical activity, it did not achieve a statistically significant improvement in 4-month PFS over the prespecified null hypothesised 4-month PFS.
BACKGROUNDMEK inhibitors have limited activity in biliary tract cancers (BTCs) as monotherapy but are hypothesized to enhance responses to programmed death ligand 1 (PD-L1) inhibition.METHODSThis ...open-label phase II study randomized patients with BTC to atezolizumab (anti-PD-L1) as monotherapy or in combination with cobimetinib (MEK inhibitor). Eligible patients had unresectable BTC with 1 to 2 lines of prior therapy in the metastatic setting, measurable disease, and Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to 1. The primary endpoint was progression-free survival (PFS).RESULTSSeventy-seven patients were randomized and received study therapy. The trial met its primary endpoint, with a median PFS of 3.65 months in the combination arm versus 1.87 months in the monotherapy arm (HR 0.58, 90% CI 0.35-0.93, 1-tail P = 0.027). One patient in the combination arm (3.3%) and 1 patient in the monotherapy arm (2.8%) had a partial response. Combination therapy was associated with more rash, gastrointestinal events, CPK elevations, and thrombocytopenia. Exploratory analysis of tumor biopsies revealed enhanced expression of antigen processing and presentation genes and an increase in CD8/FoxP3 ratios with combination treatment. Patients with higher baseline or lower fold changes in expression of certain inhibitory ligands (LAG3, BTLA, VISTA) on circulating T cells had evidence of greater clinical benefit from the combination.CONCLUSIONThe combination of atezolizumab plus cobimetinib prolonged PFS as compared with atezolizumab monotherapy, but the low response rate in both arms highlights the immune-resistant nature of BTCs.TRIAL REGISTRATIONClinicalTrials.gov NCT03201458.FUNDINGNational Cancer Institute (NCI) Experimental Therapeutics Clinical Trials Network (ETCTN); F. Hoffmann-La Roche, Ltd.; NCI, NIH (R01 CA228414-01 and UM1CA186691); NCI's Specialized Program of Research Excellence (SPORE) in Gastrointestinal Cancers (P50 CA062924); NIH Center Core Grant (P30 CA006973); and the Passano Foundation.
Objectives
Patients with cancer who are at a transition to Phase I investigational treatments have been identified as an underserved population with regard to palliative care. This disease transition ...is often accompanied by spiritual and existential concerns. The study objective was to conduct a secondary analysis of data from a larger study testing a palliative care intervention. This paper reports the findings of this secondary focus on the spiritual needs of this population.
Methods
Patients (n = 479) were accrued to this study prior to initiating a Phase I clinical trial with data collected at baseline, and 4, 12, and 24 week follow‐up.
Results
Qualitative data revealed that the transition to Phase 1 trial participation is a time of balancing hope for extended life with the reality of advancing disease. Quantitative results demonstrated increased spirituality over time in both religious‐ and non‐religious‐affiliated patients.
Conclusions
Patients entering Phase I trials have important spiritual needs as they face treatment decisions, advancing disease, and often mortality. Spiritual care should be provided to seriously ill patients as a component of quality care.
Isocitrate dehydrogenase-1 (IDH1) is mutated in up to 25% of cholangiocarcinomas, especially intrahepatic cholangiocarcinoma. Ivosidenib is an oral, targeted inhibitor of mutant IDH1 (mIDH1) approved ...in the USA for the treatment of mIDH1 acute myeloid leukaemia in newly diagnosed patients ineligible for intensive chemotherapy and patients with relapsed or refractory disease. Ivosidenib is under clinical evaluation in a phase 1 study that aims to assess its safety and tolerability in patients with mIDH1 solid tumours. Here we report data for the mIDH1-cholangiocarcinoma cohort.
We did a phase 1 dose-escalation and expansion study of ivosidenib monotherapy in mIDH1 solid tumours at 12 clinical sites in the USA and one in France. The primary outcomes were safety, tolerability, maximum tolerated dose, and recommended phase 2 dose. Eligible patients had a documented mIDH1 tumour based on local testing, an Eastern Cooperative Oncology Group performance status of 0 or 1, one or more previous lines of therapy, and evaluable disease by Response Evaluation Criteria in Solid Tumors version 1.1. During dose escalation, ivosidenib was administered orally at 200-1200 mg daily in 28-day cycles in a standard 3 + 3 design; during expansion, patients received the selected dose on the basis of pharmacodynamic, pharmacokinetic, safety, and activity data from dose escalation. Safety and clinical activity analyses were reported for all patients with mIDH1-cholangiocarcinoma who were enrolled and received at least one dose of study treatment. Enrolment is complete, and the study is ongoing. This trial is registered at ClinicalTrials.gov, number NCT02073994.
Between March 14, 2014 and May 12, 2017, 73 patients with mIDH1-cholangiocarcinoma were enrolled and received ivosidenib. No dose-limiting toxicities were reported and maximum tolerated dose was not reached; 500 mg daily was selected for expansion. Common (≥20%) adverse events, regardless of cause, were fatigue (31 42%; two 3% grade ≥3), nausea (25 34%; one 1% grade ≥3), diarrhoea (23 32%), abdominal pain (20 27%; two 3% grade ≥3), decreased appetite (20 27%; one 1% grade ≥3), and vomiting (17 23%). Common grade 3 or worse adverse events were ascites (four 5%) and anaemia (three 4%); the only treatment-related grade 3 or worse adverse event in more than one patient was fatigue (two 3%). Two (3%) patients had serious adverse events leading to on-treatment death (Clostridioides difficile infection and procedural haemorrhage); neither was assessed by the investigator as related to treatment. 46 (63%) patients had adverse events deemed related to ivosidenib, of which four (5%) were grade 3 or higher (two 3% for fatigue; one 1% each for decreased blood phosphorus and increased blood alkaline phosphatase). One serious adverse event was considered possibly related to treatment (grade 2 supraventricular extrasystoles). Four (5%; 95% CI 1·5-13·4) patients had a partial response. Median progression-free survival was 3·8 months (95% CI 3·6-7·3), 6-month progression-free survival was 40·1% (28·4-51·6), and 12-month progression-free survival was 21·8% (12·3-33·0). Median overall survival was 13·8 months (95% CI 11·1-29·3); however, data were censored for 48 patients (66%).
Ivosidenib might offer a well tolerated option for patients with mIDH1-cholangiocarcinoma. An ongoing, global phase 3 study is evaluating ivosidenib versus placebo in patients with previously treated nonresectable or metastatic mIDH1-cholangiocarcinoma.
Agios Pharmaceuticals, Inc.
Biliary tract cancers (BTC) are aggressive malignancies refractory to chemotherapy and immunotherapy. MEK inhibition (MEKi)-based regimens may have utility in this disease when combined with PD-L1 ...blockade. We hypothesize that dual MEK/PD-L1 inhibition alters circulating soluble and cellular immune mediators to improve clinical outcomes in patients with advanced BTC.
We examined immune features in peripheral blood from 77 patients with advanced BTC enrolled in a phase II clinical trial investigating atezolizumab with or without cobimetinib. Plasma and peripheral blood mononuclear cells (PBMC) were isolated from whole blood to evaluate soluble factors and immune cell populations. Baseline blood samples were additionally compared with healthy donors to identify immune signatures unique to BTC.
At baseline, the soluble factors platelet-derived growth factor B (PDGF)-BB, placental growth factor (PlGF)-1, IL5, and IL17A were elevated in patients with BTC compared with healthy adult donors, and higher baseline frequencies of CD8+BTLA+ T cells correlated with better overall survival (OS) in this trial. There were also significant treatment-related alterations in several factors, including decreased PDGF-BB following combination treatment, that correlated with improved OS and progression-free survival (PFS). Higher baseline levels of IL23 and RANTES corresponded to improved clinical outcomes following combination treatment. Dual MEK/PD-L1 inhibition increased populations of CD4+TIM3+ and decreased CD8+VISTA+ T cells, correlating with worse OS and better PFS, respectively.
This work represents a comprehensive analysis of peripheral immune features in patients with BTC and systemic responses to dual MEK/PD-L1 inhibition. These data support further investigation to understand how MEKi combines with immunotherapeutic approaches to improve clinical outcomes for patients with advanced BTC.
Microsatellite instability (MSI) is caused by defective mismatch repair in 15-20% of colorectal cancers (CRCs). Higher mutation loads in tumors with mismatch repair deficiency can predict response to ...pembrolizumab, an anti-programmed death 1 (PD-1) immune checkpoint inhibitor. We analyzed the mutations in 113 CRCs without MSI (MSS) and 29 CRCs with MSI-High (MSI-H) using the 50-gene AmpliSeq cancer panel. Overall, MSI-H CRCs showed significantly higher mutations than MSS CRCs, including insertion/deletion mutations at repeat regions. MSI-H CRCs showed higher incidences of mutations in the BRAF, PIK3CA, and PTEN genes as well as mutations in the receptor tyrosine kinase families. While the increased mutations in BRAF and PTEN in MSI-H CRCs are well accepted, we also support findings of mutations in the mTOR pathway and receptor tyrosine kinase family genes. MSS CRCs showed higher incidences of mutations in the APC, KRAS and TP53 genes, confirming previous findings. NGS assays may be designed to detect driver mutations for targeted therapeutics and to identify tumors with high mutation loads for potential treatment with immune checkpoint blockade therapies. Further studies may be warranted to elucidate potential targeted therapeutics against mutations in the mTOR pathway and the receptor tyrosine kinase family in MSI-H CRCs as well as the benefit of anti-PD-1 immunotherapy in hypermutated MSS CRCs or other cancers.
Biliary tract cancers (BTCs) are aggressive cancers that carry a poor prognosis. An enhanced understanding of the immune landscape of anatomically and molecularly defined subsets of BTC may improve ...patient selection for immunotherapy and inform immune-based combination treatment strategies.
We analyzed deidentified clinical, genomic, and transcriptomic data from the Tempus database to determine the mutational frequency and mutational clustering across the three major BTC subtypes (intrahepatic cholangiocarcinoma IHC, extrahepatic cholangiocarcinoma, and gallbladder cancer). We subsequently determined the relationship between specific molecular alterations and anatomical subsets and features of the BTC immune microenvironment.
We analyzed 454 samples of BTC, of which the most commonly detected alterations were
(42.5%),
(23.4%),
(19.6%),
(15.5%),
(15%),
(14.2%),
(11.7%),
(11.7%),
(8.4%),
(10.4%) and
(8.4%), and
fusions (8.7%). Potentially actionable molecular alterations were identified in 30.5% of BTCs including 39.1% of IHC. Integrative cluster analysis revealed four distinct molecular clusters, with cluster 4 predominately associated with
rearrangements and
mutations in IHC. Immune-related biomarkers indicative of an inflamed tumor-immune microenvironment were elevated in gallbladder cancers and in cluster 1, which was enriched for
,
, and
mutations. Multiple common driver genes, including
,
,
,
,
, and
, were individually associated with unique BTC immune microenvironments.
BTC subtypes exhibit diverse DNA alterations, RNA inflammatory signatures, and immune biomarkers. The association between specific BTC anatomical subsets, molecular alterations, and immunophenotypes highlights new opportunities for therapeutic development.
There is continued debate regarding the optimal combinations of radiation therapy and chemotherapy in the preoperative treatment of locally advanced rectal adenocarcinomas. We report our ...single-institution experience of feasibility and early oncologic outcomes of short-course preoperative radiation therapy (5 Gy X 5 fractions) followed by consolidation neoadjuvant chemotherapy.
We reviewed the records of 26 patients with locally advanced rectal adenocarcinoma. All patients underwent short course radiotherapy (5 Gy X 5 fractions) followed by chemotherapy either modified infusional and bolus 5-fluorouracail and oxalipatin (mFOLFOX6) or capecitabine and oxaliplatin prior to consideration for surgery. A full course of chemotherapy was defined as at least 8 weeks of chemotherapy.
There were five clinical (c) T2, 16 cT3, and five cT4 rectal tumors, with 88% cN+. Twenty-five patients received a median of 4 cycles (range 3 to 8) of mFOLFOX6 (with one cycle defined as a two-week period); one patient received 3 cycles of capecitabine and oxaliplatin. All patients completed SCRT; 81% completed the full course of neoadjuvant chemotherapy with 19% requiring dose reductions in chemotherapy, most commonly due to neuropathy. Nineteen patients underwent post-treatment endoscopic evaluation, and nine patients were noted to achieve a complete clinical response (CCR). Six of the nine patients who achieved CCR opted for a non-operative approach of watch-and-wait. Twenty patients underwent surgical resection; pathologic complete response was observed in seven (35%) of these twenty. The main radiation-associated toxicity was proctitis with CTCAE Grade 2 proctitis observed in seven patients (27%). Post-operative Clavien-Dindo Grade 3 complications within 30 days of surgery were identified in six patients (30%), with no Grade 4 or 5 adverse events. Median length of hospital stay was 4.5 days (range 2-16 days); three patients were readmitted within a 30 day period.
Short course preoperative radiotherapy followed by neoadjuvant chemotherapy was well-tolerated and achieved oncologic outcomes that compare favorably with short-course radiation therapy alone or long-course chemoradiotherapy. This regimen is associated with high rates of clinical and pathologic complete response.
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