Pancreatic Cancer Outcome: Local Treatment with Radiation Using MRI-Linac

PURPOSE/OBJECTIVE(S)

Stereotactic MR-guided on-table adaptive radiotherapy (SMART) is a surging modality in radiotherapy, delivering high dose radiation to the tumor in great proximity to susceptible organs. The aim of this study is to evaluate the clinical outcome in locally advanced or recurrent pancreatic tumors with or without prior irradiation.

MATERIALS/METHODS

All consecutive patients were treated in our center for pancreatic cancer (PC) using SMART technology to a prescription of 50Gy (BED10 100 Gy1o) in 5 fractions, with daily on-table adaptation of treatment plan. Endpoints for this retrospective, single center, IRB approved study were local control, overall survival, local disease-free period, acute and late toxicities.

RESULTS

Fifty-four PC patients were treated between 8.2019-9.2022, with median follow-up of 8.9 months from SMART (0.8-34 months). Forty patients had upfront inoperable PC (45% were metastatic at RT, five treated to liver metastatic lesions concomitantly) and fourteen patients had local recurrence following prior pancreatectomy, six of them had prior adjuvant RT. 87% received at least one round of chemotherapy (Oxaliplatin based- 72%), 25% received ≥2 regimens. Mean age was 68.9 (45-86) years. There was no significant difference in baseline parameters between prior pancreatectomy and inoperable groups. On-table adaptive replanning was performed for 100% of all (269) fractions (one patient received 4 fractions). No patient reported grade ≥2 acute GI toxicity. Six patients reported fatigue at the end of RT, four of them had prior radiation. Forty-eight patients were available for evaluation. Complete local control was achieved in 21.7% (10 patients) for median of 9 months (2.8-28.8 months), three had later local progression. Eight patients had regional or marginal recurrence following treatment. 6-months and 12-months OS was 75% and 52%, respectively. There was no significant difference in toxicity and outcome between post-pancreatectomy and inoperable groups.

CONCLUSION

Pancreatic cancer local ablative SMART is safe, with minimal treatment-related toxicity, even in previously irradiated patients. Local control with complete response was achieved by 20% of patients. Further studies are needed to evaluate long-term outcome and late toxicity.

A systematic review and meta-analysis of germline BRCA mutations in pancreatic cancer patients identifies global and racial disparities in access to genetic testing

BACKGROUND

Germline BRCA1 and BRCA2 mutations (gBRCAm) can inform pancreatic cancer (PC) risk and treatment but most of the available information is derived from white patients. The ethnic and geographic variability of gBRCAm prevalence and of germline BRCA (gBRCA) testing uptake in PC globally is largely unknown.

MATERIALS AND METHODS

We carried out a systematic review and prevalence meta-analysis of gBRCA testing and gBRCAm prevalence in PC patients stratified by ethnicity. The main outcome was the distribution of gBRCA testing uptake across diverse populations worldwide. Secondary outcomes included: geographic distribution of gBRCA testing uptake, temporal analysis of gBRCA testing uptake in ethnic groups, and pooled proportion of gBRCAm stratified by ethnicity. The study is listed under PROSPERO registration number #CRD42022311769.

RESULTS

A total of 51 studies with 16 621 patients were included. Twelve of the studies (23.5%) enrolled white patients only, 10 Asians only (19.6%), and 29 (56.9%) included mixed populations. The pooled prevalence of white, Asian, African American, and Hispanic patients tested per study was 88.7%, 34.8%, 3.6%, and 5.2%, respectively. The majority of included studies were from high-income countries (HICs) (64; 91.2%). Temporal analysis showed a significant increase only in white and Asians patients tested from 2000 to present (P < 0.001). The pooled prevalence of gBRCAm was: 3.3% in white, 1.7% in Asian, and negligible (<0.3%) in African American and Hispanic patients.

CONCLUSIONS

Data on gBRCA testing and gBRCAm in PC derive mostly from white patients and from HICs. This limits the interpretation of gBRCAm for treating PC across diverse populations and implies substantial global and racial disparities in access to BRCA testing in PC.

First-in-human phase 1 study of the anti-TIGIT antibody vibostolimab as monotherapy or with pembrolizumab for advanced solid tumors, including non-small cell lung cancer

BACKGROUND

In this first-in-human phase 1 study, we investigated the safety and efficacy of the anti-TIGIT antibody vibostolimab as monotherapy or in combination with pembrolizumab.

METHODS

Part A enrolled patients with advanced solid tumors and part B enrolled patients with non-small cell lung cancer (NSCLC). Patients received vibostolimab 2.1-700 mg alone or with pembrolizumab 200 mg in part A and vibostolimab 200 mg alone or with pembrolizumab 200 mg in part B. Primary end points were safety and tolerability. Secondary end points included pharmacokinetics and objective response rate (ORR) per RECIST v1.1.

RESULTS

Part A enrolled 76 patients (monotherapy, 34; combination therapy, 42). No dose-limiting toxicities were reported. Across doses, 56% of patients receiving monotherapy and 62% receiving combination therapy had treatment-related adverse events (TRAEs); grade 3-4 TRAEs occurred in 9% and 17% of patients, respectively. The most common TRAEs were fatigue (15%) and pruritus (15%) with monotherapy and pruritus (17%) and rash (14%) with combination therapy. Confirmed ORR was 0% with monotherapy and 7% with combination therapy. In part B, 39 patients had anti-PD-1/PD-L1-naïve NSCLC (all received combination therapy) and 67 had anti-PD-1/PD-L1-refractory NSCLC (monotherapy, 34; combination therapy, 33). In patients with anti-PD-1/PD-L1-naive NSCLC: 85% had TRAEs-the most common were pruritus (38%) and hypoalbuminemia (31%); confirmed ORR was 26%, with responses occurring in both PD-L1-positive and PD-L1-negative tumors. In patients with anti-PD-1/PD-L1‒refractory NSCLC: 56% receiving monotherapy and 70% receiving combination therapy had TRAEs-the most common were rash and fatigue (21% each) with monotherapy and pruritus (36%) and fatigue (24%) with combination therapy; confirmed ORR was 3% with monotherapy and 3% with combination therapy.

CONCLUSION

Vibostolimab plus pembrolizumab was well tolerated and demonstrated antitumor activity in patients with advanced solid tumors, including patients with advanced NSCLC.

Identification and diagnosis of Secondary Progressive Multiple Sclerosis during the clinical encounter: Results from a physician survey

BACKGROUND

It is difficult to characterize the transition from relapsing-remitting multiple sclerosis (RRMS) to secondary progressive MS (SPMS), due to symptomatic variability across patients. Diagnosis of SPMS is prolonged and often established retrospectively, as it is based on patient clinical history and symptoms. This cross-sectional study aimed to identify MS neurologist reported clinical indicators deemed important in diagnosing SPMS in clinical practice.

METHODS

A web-based quantitative survey was conducted among MS-treating neurologists across the United States in January 2019. The questionnaire comprised of 17 questions evaluating primary clinical indicators used by neurologists in assessing patient progression to SPMS. Treatment approach and factors influencing treatment decision-making following SPMS diagnosis were also analyzed in the survey.

RESULTS

Overall, 300 neurologists completed the survey; most of the respondents were general MS-treating neurologists (63%) and from private care setting (58%). The overall respondents as well as MS-focused neurologists ranked patient history (45% and 42%, respectively) and patients' neurological exam (39% and 44%, respectively) as -primary clinical indicators of SPMS diagnosis. 57% of neurologists always or mostly switched disease modifying therapies after progression to SPMS, and mostly considered 3-6 months' assessment interval to diagnose SPMS.

CONCLUSION

The survey indicated that neurologists are able to recognize signs of SPMS within six months of symptomatic assessment. The diagnosis is primarily based on patient history among MS-treating neurologists. Therefore, continued education to neurologists may facilitate early diagnosis and timely introduction of effective treatment to manage the progression of SPMS.

Reshaping preoperative treatment of pancreatic cancer in the era of precision medicine

This review summarises the recent evidence on preoperative therapeutic strategies in pancreatic cancer and discusses the rationale for an imminent need for a personalised therapeutic approach in non-metastatic disease. The molecular diversity of pancreatic cancer and its influence on prognosis and treatment response, combined with the failure of 'all-comer' treatments to significantly impact on patient outcomes, requires a paradigm shift towards a genomic-driven approach. This is particularly important in the preoperative, potentially curable setting, where a personalised treatment allocation has the substantial potential to reduce pancreatic cancer mortality.

Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

Health-related quality of life in patients with a germline BRCA mutation and metastatic pancreatic cancer receiving maintenance olaparib

BACKGROUND

Patients with metastatic pancreatic cancer often have a detriment in health-related quality of life (HRQoL). In the randomized, double-blind, phase III POLO trial progression-free survival was significantly longer with maintenance olaparib, a poly(ADP-ribose) polymerase inhibitor, than placebo in patients with a germline BRCA1 and/or BRCA2 mutation (gBRCAm) and metastatic pancreatic cancer whose disease had not progressed during first-line platinum-based chemotherapy. The prespecified HRQoL evaluation is reported here.

PATIENTS AND METHODS

Patients were randomized to receive maintenance olaparib (300 mg b.i.d.; tablets) or placebo. HRQoL was assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30-item module at baseline, every 4 weeks until disease progression, at discontinuation, and 30 days after last dose. Scores ranged from 0 to 100; a ≥10-point change or difference between arms was considered clinically meaningful. Adjusted mean change from baseline was analysed using a mixed model for repeated measures. Time to sustained clinically meaningful deterioration (TSCMD) was analysed using a log-rank test.

RESULTS

Of 154 randomized patients, 89 of 92 olaparib-arm and 58 of 62 placebo-arm patients were included in HRQoL analyses. The adjusted mean change in Global Health Status (GHS) score from baseline was <10 points in both arms and there was no significant between-group difference [-2.47; 95% confidence interval (CI) -7.27, 2.33; P = 0.31]. Analysis of physical functioning scores showed a significant between-group difference (-4.45 points; 95% CI -8.75, -0.16; P = 0.04). There was no difference in TSCMD for olaparib versus placebo for GHS [P = 0.25; hazard ratio (HR) 0.72; 95% CI 0.41, 1.27] or physical functioning (P = 0.32; HR 1.38; 95% CI 0.73, 2.63).

CONCLUSIONS

HRQoL was preserved with maintenance olaparib treatment with no clinically meaningful difference compared with placebo. These results support the observed efficacy benefit of maintenance olaparib in patients with a gBRCAm and metastatic pancreatic cancer.

CLINCALTRIALS.GOV NUMBER

NCT02184195.

Publisher's Note: Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer [Phys. Rev. Lett. 116, 071802 (2016)]

This corrects the article DOI: 10.1103/PhysRevLett.116.071802.

Search for CP Violation in Neutrino and Antineutrino Oscillations by the T2K Experiment with 2.2×10^{21} Protons on Target

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3}  eV^{2}/c^{4}.

Direct Measurement of Nuclear Dependence of Charged Current Quasielasticlike Neutrino Interactions Using MINERvA

Charged-current ν_{μ} interactions on carbon, iron, and lead with a final state hadronic system of one or more protons with zero mesons are used to investigate the influence of the nuclear environment on quasielasticlike interactions. The transferred four-momentum squared to the target nucleus, Q^{2}, is reconstructed based on the kinematics of the leading proton, and differential cross sections versus Q^{2} and the cross-section ratios of iron, lead, and carbon to scintillator are measured for the first time in a single experiment. The measurements show a dependence on the atomic number. While the quasielasticlike scattering on carbon is compatible with predictions, the trends exhibited by scattering on iron and lead favor a prediction with intranuclear rescattering of hadrons accounted for by a conventional particle cascade treatment. These measurements help discriminate between different models of both initial state nucleons and final state interactions used in the neutrino oscillation experiments.

Measurement of Neutral-Current K^{+} Production by Neutrinos using MINERvA

Neutral-current production of K^{+} by atmospheric neutrinos is a background in searches for the proton decay p→K^{+}ν[over ¯]. Reactions such as νp→νK^{+}Λ are indistinguishable from proton decays when the decay products of the Λ are below detection threshold. Events with K^{+} are identified in MINERvA by reconstructing the timing signature of a K^{+} decay at rest. A sample of 201 neutrino-induced neutral-current K^{+} events is used to measure differential cross sections with respect to the K^{+} kinetic energy, and the non-K^{+} hadronic visible energy. An excess of events at low hadronic visible energy is observed relative to the prediction of the neut event generator. Good agreement is observed with the cross section prediction of the genie generator. A search for photons from π^{0} decay, which would veto a neutral-current K^{+} event in a proton decay search, is performed, and a 2σ deficit of detached photons is observed relative to the genie prediction.

Combined Analysis of Neutrino and Antineutrino Oscillations at T2K

T2K reports its first results in the search for CP violation in neutrino oscillations using appearance and disappearance channels for neutrino- and antineutrino-mode beams. The data include all runs from January 2010 to May 2016 and comprise 7.482×10^{20} protons on target in neutrino mode, which yielded in the far detector 32 e-like and 135  μ-like events, and 7.471×10^{20} protons on target in antineutrino mode, which yielded 4 e-like and 66  μ-like events. Reactor measurements of sin^{2}2θ_{13} have been used as an additional constraint. The one-dimensional confidence interval at 90% for the phase δ_{CP} spans the range (-3.13, -0.39) for normal mass ordering. The CP conservation hypothesis (δ_{CP}=0, π) is excluded at 90% C.L.

Evidence for Neutral-Current Diffractive π^{0} Production from Hydrogen in Neutrino Interactions on Hydrocarbon

The MINERvA experiment observes an excess of events containing electromagnetic showers relative to the expectation from Monte Carlo simulations in neutral-current neutrino interactions with mean beam energy of 4.5 GeV on a hydrocarbon target. The excess is characterized and found to be consistent with neutral-current π^{0} production with a broad energy distribution peaking at 7 GeV and a total cross section of 0.26±0.02(stat.)±0.08(sys.)×10^{-39}  cm^{2}. The angular distribution, electromagnetic shower energy, and spatial distribution of the energy depositions of the excess are consistent with expectations from neutrino neutral-current diffractive π^{0} production from hydrogen in the hydrocarbon target. These data comprise the first direct experimental observation and constraint for a reaction that poses an important background process in neutrino-oscillation experiments searching for ν_{μ} to ν_{e} oscillations.

Evidence of Coherent K^{+} Meson Production in Neutrino-Nucleus Scattering

Neutrino-induced charged-current coherent kaon production ν_{μ}A→μ^{-}K^{+}A is a rare, inelastic electroweak process that brings a K^{+} on shell and leaves the target nucleus intact in its ground state. This process is significantly lower in rate than the neutrino-induced charged-current coherent pion production because of Cabibbo suppression and a kinematic suppression due to the larger kaon mass. We search for such events in the scintillator tracker of MINERvA by observing the final state K^{+}, μ^{-}, and no other detector activity, and by using the kinematics of the final state particles to reconstruct the small momentum transfer to the nucleus, which is a model-independent characteristic of coherent scattering. We find the first experimental evidence for the process at 3σ significance.

Measurement of Electron Neutrino Quasielastic and Quasielasticlike Scattering on Hydrocarbon at ⟨E_{ν}⟩=3.6 GeV

The first direct measurement of electron neutrino quasielastic and quasielasticlike scattering on hydrocarbon in the few-GeV region of incident neutrino energy has been carried out using the MINERvA detector in the NuMI beam at Fermilab. The flux-integrated differential cross sections in the electron production angle, electron energy, and Q^{2} are presented. The ratio of the quasielastic, flux-integrated differential cross section in Q^{2} for ν_{e} with that of similarly selected ν_{μ}-induced events from the same exposure is used to probe assumptions that underpin conventional treatments of charged-current ν_{e} interactions used by long-baseline neutrino oscillation experiments. The data are found to be consistent with lepton universality and are well described by the predictions of the neutrino event generator GENIE.

Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer

Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current ν_{μ} interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.

Abstract OT1-01-04: A multicenter, phase 1b, first-in-human dose-escalation study of ADXS31-164, a Listeria monocytogenes-LLO immunotherapy, in patients with HER2-expressing solid tumors

Background: Wild type Listeria monocytogenes (Lm) is taken up by antigen-presenting cells (APCs) and has the capability to escape destruction in the phagolysosome and proliferate in the cytosol of the APC. ADXS31-164 is a live attenuated Lm-listeriolysin O (LLO) immunotherapy bioengineered to express the intracellular domain 1 and extracellular domains 1 and 2 of chimeric human epidermal growth factor receptor 2 (cHER2) as a fusion protein to a truncated form of the LLO (tLLO) in the cytoplasm of APCs. The resultant immunologic response generates tumor antigen-specific cytotoxic T lymphocytes while also inhibiting regulatory T cells and myeloid-derived suppressor cells in the tumor microenvironment. Preclinical studies have shown ADXS31-164 can delay the progression of tumors in both transplantable and autochthonous HER2-expressing mouse tumor models.

Trial Design: This is an open-label, multicenter Phase 1b trial (NCT02386501). Patients will receive ADXS31-164 every 3 weeks until progression of disease or unacceptable toxicity. Dose escalations will be performed according to a standard 3+3 design starting at 1 × 109 colony forming units (CFU) to a maximum dose level of 1 × 1010 CFU.

The maximum tolerated dose (MTD) will be identified as the dose level in which a dose-limiting toxicity is seen in 2 of 6 patients; the previous dose level will be selected as the recommended Phase 2 dose (RP2D). Once the MTD and RP2D have been identified, up to 4 HER2-overexpressing tumor-specific expansion cohorts will be evaluated. Treatment cycles can be repeated at the RP2D (or less) for each patient until a study discontinuation criterion is met or the subject completes 1 cycle of treatment post-observation of complete response. Blood samples will be evaluated for immunologic effects in cycle 1 only. Descriptive statistics will be used to evaluate the safety and tolerability of ADXS31-164.

Objectives: The primary aim of this trial is to evaluate safety and tolerability of ADXS31-164 in patients with solid tumors that express HER2, and to select the RP2D. Secondary objectives include tumor response rates and progression-free survival (measured by Response Evaluation Criteria In Solid Tumors [RECIST] 1.1 and immune-related RECIST criteria). Exploratory analyses will describe and evaluate data from correlative immunologic studies.

Key Eligibility Criteria: Patients aged ≥18 years with HER2-positive tumors determined by fluorescence in situ hybridization (FISH) or immunohistochemistry (IHC, at least 1 positive in 1% of the evaluable tumor cells) and an Eastern Cooperative Oncology Group performance status of 0–1 are eligible. Additional criteria include a diagnosis of locally advanced/metastatic solid tumor that has progressed or become intolerant to standard therapy or for which no standard therapy is available, measurable and/or evaluable disease per RECIST 1.1, and a left ventricular ejection fraction within normal limits.

Citation Format: Tan AR, Olszanski A, Golan T, Mauro D, Rugo H. A multicenter, phase 1b, first-in-human dose-escalation study of ADXS31-164, a Listeria monocytogenes-LLO immunotherapy, in patients with HER2-expressing solid tumors. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT1-01-04.