Safety and antitumor activity of the anti-PD-1 antibody pembrolizumab in patients with recurrent carcinoma of the anal canal

Background

Safety and efficacy of pembrolizumab, a humanized programmed death 1 monoclonal antibody, was assessed in KEYNOTE-028, a multicohort, phase Ib trial for patients with programmed death ligand 1 (PD-L1)-positive advanced solid tumors. We report results for the cohort of patients with advanced anal carcinoma.

Patients and methods

Patients with PD-L1-positive tumors (≥1%) received intravenous pembrolizumab 10 mg/kg once every 2 weeks for up to 2 years or until confirmed progression or unacceptable toxicity. Response was assessed every 8 weeks for the first 6 months and every 12 weeks thereafter per Response Evaluation Criteria In Solid Tumors, version 1.1. Primary endpoints were safety and overall response rate per investigator review. Secondary endpoints included progression-free survival, overall survival, and response duration. Data cutoff date was 1 July 2015.

Results

Of the 43 patients with advanced anal carcinoma evaluable for PD-L1 expression, 32 (74%) had PD-L1-positive tumors as assessed with the 22C3 prototype assay, of whom 25 were enrolled between April and September 2014. Sixteen patients (64%) experienced treatment-related adverse events; the most common ones were diarrhea and fatigue in four patients (16%) each and nausea in three patients (12%). There were no treatment-related deaths or discontinuations as of the data cutoff date. Among the 24 patients with squamous cell carcinoma histology, four had confirmed partial response, for an overall response rate of 17% [95% confidence interval (CI), 5%-37%) and 10 (42%) had confirmed stable disease, for a disease control rate of 58%. One additional patient with non-squamous histology had confirmed stable disease.

Conclusion

In this population of patients with PD-L1-positive advanced squamous cell anal carcinoma, pembrolizumab demonstrated a manageable safety profile and encouraging antitumor activity. These data support further study of pembrolizumab for this patient population.

ClinicalTrials.gov

NCT02054806.

Neutrophils in Gliomas

Neutrophils are the most abundant white blood cells and are the first recruited to inflammatory sites. Neutrophils are an important component of the tumor stroma and can exert both anti-tumoral and pro-tumoral activities, depending on their maturation and activation state. In human gliomas, the number of circulating and infiltrating neutrophils correlates with the severity of the disease, indicating a prognostic and possible pro-tumoral role for these leukocytes. In glioma preclinical models, neutrophils promote tumor growth and orchestrate the resistance to anti-angiogenic therapies. Nevertheless, recent data indicate that neutrophils can be activated to directly kill tumor cells or to orchestrate the anti-tumoral response. Here, we review current knowledge about the role of neutrophils in glioma and their possible involvement in new strategies to improve current cancer therapies.

Phase II Study of Everolimus in Patients With Thymoma and Thymic Carcinoma Previously Treated With Cisplatin-Based Chemotherapy

Purpose No effective salvage treatments are available for patients with advanced/recurrent thymoma (T) or thymic carcinoma (TC) who have progressed after platinum-based chemotherapy. This study evaluated the activity of everolimus in patients with advanced/recurrent T or TC previously treated with cisplatin-containing chemotherapy. Patients and Methods This was a single-arm, single-stage, open-label, multicenter, phase II trial. Patients received oral everolimus 10 mg/d until disease progression, unacceptable toxicity, or patient refusal. A Fleming phase II trial was designed. The null hypothesis of a true disease control rate (DCR) of 40% was tested against a one-sided alternative of a true DCR of 60% (α = β = 0.10): If disease control were achieved in ≥ 21 of the first 41 evaluable patients, everolimus could be recommended for further evaluation. Progression-free survival, overall survival, and safety were also evaluated. Results From 2011 to 2013, 51 patients were enrolled (T, n = 32; TC, n = 19). Complete remission was observed in one patient with TC, partial response in five patients (T, n = 3; TC, n = 2), and stable disease in 38 patients (T, n = 27; TC, n= 11), with a DCR of 88% (T,: 93.8%; TC, 77.8%). With a median follow up of 25.7 months, median progression-free survival was 10.1 months (T,: 16.6 months; TC, 5.6 months), and median overall survival was 25.7 months (T, not reached; TC, 14.7 months). Fourteen patients had a serious drug-related adverse event; of these patients, nine permanently discontinued treatment. Three patients died of pneumonitis while in the study. Immunohistochemical positivity for p4E-BP1 or insulin-like growth factor-1 receptor was statistically significantly related to a shorter survival. Conclusion Everolimus may induce durable disease control in a high percentage of patients with T or TC, albeit with a potential high risk of fatal pneumonitis.

Phase II Study of Asparagine-Glycine-Arginine–Human Tumor Necrosis Factor α, a Selective Vascular Targeting Agent, in Previously Treated Patients With Malignant Pleural Mesothelioma

Purpose

NGR-hTNF consists of human tumor necrosis factor α (hTNF-α) fused to the tumor-homing peptide asparagine-glycine-arginine (NGR) able to selectively bind an aminopeptidase N isoform overexpressed on tumor blood vessels. Hypervascularity is a prominent and poor-prognosis feature of malignant pleural mesothelioma (MPM). Currently, there are no standard options for patients with MPM who are failing a front-line pemetrexed-based regimen. We explored safety and efficacy of NGR-hTNF in this setting.

Patients and Methods

Eligible patients had radiologically documented tumor progression and performance status ≤ 2. Primary study aim was progression-free survival (PFS). NGR-hTNF 0.8 μg/m2 was given intravenously every 3 weeks. A subsequent cohort of patients received 0.8 μg/m2 on a weekly basis.

Results

In the triweekly cohort (n = 43), only one grade 3 drug-related toxicity was noted, and the most common grades 1 to 2 were short-lived chills (71%). The median PFS was 2.8 months (95% CI, 2.3 to 3.3 months). Nineteen patients (44%) had disease control (one had partial response, and 18 had stable diseases) and experienced a median progression-free time of 4.4 months. In the weekly cohort (n = 14), there was no higher toxicity, and median PFS was 3.0 months (95% CI, 1.9 to 4.1 months). Seven patients (50%) had disease control (all stable diseases) and had a median progression-free interval of 9.1 months. In the overall study population (N = 57), median PFS was 2.8 months. Median progression-free time was 4.7 months in twenty-six patients (46%) who achieved disease control. Median survival was 12.1 months.

Conclusion

The tolerability and disease control of NGR-hTNF 0.8 μg/m2 weekly warrant additional evaluation in patients with advanced MPM.

Advances in the biology of malignant pleural mesothelioma

Malignant pleural mesothelioma is a highly aggressive cancer with a very poor prognosis. Although the mechanism of carcinogenesis is not fully understood, approximately 80% of malignant pleural mesothelioma can be attributed to asbestos fiber exposure. This disease is largely unresponsive to conventional chemotherapy or radiotherapy, and most patients die within 10-17 months of their first symptoms. Currently, malignant pleural mesothelioma therapy is guided by clinical stage and patient characteristics rather than by the histological or molecular features of the tumor. Several molecular pathways involved in malignant pleural mesothelioma have been identified; these include cell cycle regulation, apoptosis, growth factor pathways, and angiogenesis. Unfortunately, several agents targeting these processes, including erlotinib, gefitinib, and imatinib, have proven ineffective in clinical trials. A greater understanding of the molecular pathways involved in malignant pleural mesothelioma is needed to develop better diagnostics, therapeutics, and preventative measures. Moreover, understanding the biological basis of mesothelioma progression may facilitate personalized treatment approaches, and early identification of poor prognostic indicators may help reduce the heterogeneity of the clinical response. This paper reviews advances in the molecular biology of malignant pleural mesothelioma in terms of pathogenesis, the major molecular pathways and the associated therapeutic strategies, and the roles of biomarkers.

Treatment with pembrolizumab in programmed death ligand 1-positive recurrent glioblastoma: Results from the multicohort phase 1 KEYNOTE-028 trial

BACKGROUND

Current treatments for recurrent glioblastoma offer limited benefit. The authors report the antitumor activity and safety of the anti-programmed death 1 (anti-PD-1) immunotherapy, pembrolizumab, in programmed death ligand 1 (PD-L1)-positive, recurrent glioblastoma.

METHODS

Adult patients with PD-L1-positive tumors were enrolled in the recurrent glioblastoma cohort of the multicohort, phase 1b KEYNOTE-028 study (ClinicalTrials.gov identifier, NCT02054806) and received pembrolizumab 10 mg/kg every 2 weeks for up to 2 years. The primary endpoint was investigator-assessed overall response rate according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Archival tumor samples were assessed for PD-L1 expression levels (prospectively) and T-cell-inflamed gene expression profile score (retrospectively).

RESULTS

After a median follow-up of 14 months (range, 2-55 months) among the 26 enrolled patients, the overall response rate was 8% (95% CI, 1%-26%). Two partial responses, lasting 8.3 and 22.8 months, occurred. Progression-free survival (median, 2.8 months; 95% CI, 1.9-8.1 months) rate at 6 months was 37.7%, and the overall survival (median, 13.1 months; 95% CI, 8.0-26.6 months) rate at 12 months was 58%. Correlation of therapeutic benefit to level of PD-L1 expression, gene expression profile score, or baseline steroid use could not be established. Treatment-related adverse events occurred in 19 patients (73%), and 5 patients experienced grade 3 or 4 events (there were no grade 5 events). Immune-mediated adverse events and infusion reactions occurred in 7 patients (27%).

CONCLUSIONS

Pembrolizumab monotherapy demonstrated durable antitumor activity in a subset of patients with manageable toxicity in this small, signal-finding, recurrent glioblastoma cohort. Future studies evaluating rationally designed pembrolizumab combination regimens may improve outcomes in patients with recurrent glioblastoma.

Thymidylate synthase and excision repair cross-complementing group-1 as predictors of responsiveness in mesothelioma patients treated with pemetrexed/carboplatin

PURPOSE

The pemetrexed/platinum agent combination represents the standard of care in first-line treatment for malignant pleural mesothelioma (MPM). However, there are no established indicators of responsiveness that can be used to optimize the treatment. This retrospective study aimed to assess the role of excision repair cross-complementing group-1 (ERCC1) and thymidylate synthase (TS) in tumors, and correlate expression levels and polymorphisms of these key determinants of drug activity with the outcome of MPM patients treated with carboplatin/pemetrexed in first-line setting.

EXPERIMENTAL DESIGN

Analysis of TS and ERCC1 polymorphisms, mRNA and protein expression was done by PCR and immunohistochemistry [with the H-score (histologic score)] in tumor specimens from 126 MPM patients, including 99 carboplatin-/pemetrexed-treated patients.

RESULTS

A significant correlation between low TS protein expression and disease control (DC) to carboplatin/pemetrexed therapy (P = 0.027), longer progression-free survival (PFS; P = 0.017), and longer overall survival (OS; P = 0.022) was found when patients were categorized according to median H-score. However, patients with the higher tertile of TS mRNA expression correlated with higher risk of developing progressive disease (P = 0.022), shorter PFS (P < 0.001), and shorter OS (P < 0.001). At multivariate analysis, the higher tertile of TS mRNA level and TS H-score confirmed their independent prognostic role for DC, PFS, and OS. No significant associations were found among ERCC1 protein expression, TS and ERCC1 polymorphisms, and clinical outcome.

CONCLUSIONS

In our series of carboplatin-/pemetrexed-treated MPM patients, low TS protein and mRNA levels were significantly associated to DC, improved PFS, and OS. Prospective trials for the validation of the prognostic/predictive role of TS in MPM patients treated with pemetrexed-based regimens are warranted.

Second-line chemotherapy in malignant pleural mesothelioma: results of a retrospective multicenter survey

The pemetrexed-cisplatin chemotherapy is standard of care in first-line (FL) treatment of malignant pleural mesothelioma (MPM). The second-line (SL) chemotherapy is considered, but the optimal treatment has not been defined yet. The aim of this study was to evaluate the clinical outcomes of SL-therapy in a series of MPM-patients included in a retrospective multicenter database. Clinical records of MPM-patients who received SL-treatment from 1996 to 2008 were reviewed. Study endpoints were response, overall-survival (OS), and progression-free-survival (PFS) for SL, stratified for patient characteristics, FL-outcomes, and type of SL. Out of 423 patients, 181 with full clinical data were identified. Patients' characteristics: median-age 64 years (range: 36-85); male gender 115 (63.5%); good EORTC-score 109 (60.2%); epithelial histology 135 (74.6%). After FL, 147 (81.2%) patients achieved disease-control (DC) and 45 had a time-to-progression≥12 months (TTP≥12). After SL, 95 patients (52.6%) achieved DC (21 response; 74 stable-disease); median PFS and OS were 4.3 and 8.7 months, respectively. According to multivariate analysis, DC after SL-therapy was significantly related to pemetrexed-based treatment (OR: 2.46; p=0.017) and FL-TTP≥12 (OR: 3.50; p=0.006). PFS was related to younger age (<65 years) (HR: 0.70; p=0.045), ECOG-PS0 (HR: 0.67; p=0.022), and FL-TTP≥12 (HR: 0.45; p<0.001). OS was significantly related to ECOG-PS0 (HR: 0.43; p<0.001) and to FL-TTP≥12 (HR: 0.54; p=0.005). In pemetrexed pre-treated patients, re-treatment with a pemetrexed/platinum combination significantly reduced the risk-of-death than pemetrexed alone (HR: 0.11; p<0.001). In conclusion, SL-chemotherapy seems to be active in MPM-patients, particularly in younger patients with ECOG-PS0 and prolonged TTP after FL-pemetrexed-based chemotherapy. In selected patients, re-challenge with pemetrexed-based regimens, preferentially associated with platinum-compound, appears to be an option for SL-setting. Considering the important limitations of this study, due to retrospective nature and the possible selection bias, prospective clinical trials are warranted to clarify these issues.

A Phase-1b study of tivantinib (ARQ 197) in adult patients with hepatocellular carcinoma and cirrhosis

BACKGROUND

The mesenchymal-epithelial transition factor (MET) receptor is dysregulated in hepatocellular carcinoma (HCC), and tivantinib (ARQ 197) is an oral, selective, MET inhibitor.

METHODS

This Phase-1b study assessed tivantinib safety as primary objective in patients with previously treated HCC and Child-Pugh A or B liver cirrhosis. Patients received oral tivantinib 360 mg twice daily until disease progression or unacceptable toxicity.

RESULTS

Among 21 HCC patients, common drug-related adverse events (AEs) were neutropaenia, anaemia, asthenia, leucopaenia, anorexia, diarrhoea, and fatigue. No drug-related worsening of liver function or performance status occurred, but one Child-Pugh B patient experienced drug-related bilirubin increase. Four patients had drug-related serious AEs, including one neutropaenia-related death. Haematologic toxicities were more frequent than in previous tivantinib studies but were manageable with prompt therapy. Best response was stable disease (median, 5.3 months) in 9 of 16 evaluable patients (56%). Median time to progression was 3.3 months.

CONCLUSION

Tivantinib demonstrated a manageable safety profile and preliminary antitumour activity in patients with HCC and Child-Pugh A or B cirrhosis.

Prognostic value of molecular and imaging biomarkers in patients with supratentorial glioma

PURPOSE

We evaluated the relationship between ¹¹C-methionine PET (¹¹C-METH PET) findings and molecular biomarkers in patients with supratentorial glioma who underwent surgery.

METHODS

A consecutive series of 109 patients with pathologically proven glioma (64 men, 45 women; median age 43 years) referred to our Institution from March 2012 to January 2015 for tumour resection and who underwent preoperative ¹¹C-METH PET were analysed. Semiquantitative evaluation of the ¹¹C-METH PET images included SUVmax, region of interest-to-normal brain SUV ratio (SUVratio) and metabolic tumour volume (MTV). Imaging findings were correlated with disease outcome in terms of progression-free survival (PFS), and compared with other clinical biological data, including IDH1 mutation status, 1p/19q codeletion and MGMT promoter methylation. The patients were monitored for a mean period of 16.7 months (median 13 months).

RESULTS

In all patients, the tumour was identified on ¹¹C-METH PET. Significant differences in SUVmax, SUVratio and MTV were observed in relation to tumour grade (p < 0.001). IDH1 mutation was found in 49 patients, 1p/19q codeletion in 58 patients and MGMT promoter methylation in 74 patients. SUVmax and SUVratio were significantly inversely correlated with the presence of IDH1 mutation (p < 0.001). Using the 2016 WHO classification, SUVmax and SUVratio were significantly higher in patients with primary glioblastoma (IDH1-negative) than in those with other diffuse gliomas (p < 0.001). Relapse or progression was documented in 48 patients (median PFS 8.7 months). Cox regression analysis showed that SUVmax and SUVratio, tumour grade, tumour type on 2016 WHO classification, IDH1 mutation status, 1p/19q codeletion and MGMT promoter methylation were significantly associated with PFS. None of these factors was found to be an independent prognostic factor in multivariate analysis.

CONCLUSION

¹¹C-METH PET parameters are significantly correlated with histological grade and IDH1 mutation status in patients with glioma. Grade, pathological classification, molecular biomarkers, SUVmax and SUVratio were prognostic factors for PFS in this cohort of patients. The trial was registered with ClinicalTrials.gov (registration: NCT02518061).

Association of supratotal resection with progression-free survival, malignant transformation, and overall survival in lower-grade gliomas

BACKGROUND

Supratotal resection is advocated in lower-grade gliomas (LGGs) based on theoretical advantages but with limited verification of functional risk and data on oncological outcomes. We assessed the association of supratotal resection in molecularly defined LGGs with oncological outcomes.

METHODS

Included were 460 presumptive LGGs; 404 resected; 347 were LGGs, 319 isocitrate dehydrogenase (IDH)-mutated, 28 wildtype. All patients had clinical, imaging, and molecular data. Resection aimed at supratotal resection without any patient or tumor a priori selection. The association of extent of resection (EOR), categorized on volumetric fluid attenuated inversion recovery images as residual tumor volume, along with postsurgical management with progression-free survival (PFS), malignant (M)PFS, and overall survival (OS) assessed by univariate, multivariate, and propensity score analysis. The study mainly focused on IDH-mutated LGGs, the "typical LGGs."

RESULTS

Median follow-up was 6.8 years (interquartile range, 5-8). Out of 319 IDH-mutated LGGs, 190 (59.6%) progressed, median PFS: 4.7 years (95% CI: 4-5.3). Total and supratotal resection obtained in 39% and 35% of patients with IDH1-mutated tumors. In IDH-mutated tumors, most patients in the partial/subtotal group progressed, 82.4% in total, only 6 (5.4%) in supratotal. Median PFS was 29 months (95% CI: 25-36) in subtotal, 46 months (95% CI: 38-48) in total, while at 92 months, PFS in supratotal was 94.0%. There was no association with molecular subtypes and grade. At random forest analysis, PFS strongly associated with EOR, radiotherapy, and previous treatment. In the propensity score analysis, EOR associated with PFS (hazard ratio, 0.03; 95% CI: 0.01-0.13). MPFS occurred in 32.1% of subtotal total groups; 1 event in supratotal. EOR, grade III, previous treatment correlated to MPFS. At random forest analysis, OS associated with EOR as well.

CONCLUSIONS

Supratotal resection strongly associated with PFS, MPFS, and OS in LGGs, regardless of molecular subtypes and grade, right from the beginning of clinical presentation.

Insulin-like growth factor-1 receptor and phosphorylated AKT-serine 473 expression in 132 resected thymomas and thymic carcinomas

BACKGROUND

Thymic malignancies are rare tumors. The insulin-like growth factor-1 (IGF-1)/IGF-1 receptor (IGF-1R) system is involved in the development of the thymus. IGF-1R expression in thymic epithelial malignancies is unknown.

METHODS

The authors investigated the expression of IGF-1R and phosphorylated AKT serine 473 (p-AKT) by using immunohistochemistry and examined the clinicopathologic correlations in a retrospective, single-institution surgical series of 132 patients with thymic epithelial malignancies.

RESULTS

Earlier disease stage, less aggressive histologic types, and complete resection were significant positive prognostic factors for disease-related survival and progression-free survival, and being a woman was a better prognostic factor for disease-related survival. IGF-1R and p-AKT protein levels were expressed in 20% and 36% of thymic tumors, respectively. Both markers were expressed more commonly in recurrent disease than in primary tumors, in more aggressive subtypes, and in more advanced disease stages. There was a trend toward better survival and progression-free survival in patients who were negative for IGF-1R or p-AKT expression in the whole series. When only the 91 primary tumors, IGF1R expression was associated with worse progression-free survival (P < .001).

CONCLUSIONS

The current retrospective analysis demonstrated that disease stage, tumor histology, sex, and resection type were major prognostic factors in the survival of patients with thymic malignancies. The expression levels of IGF-1R and p-AKT in thymic tumors suggested that IGF-1R is a potential target for treatment.

Phase 1 trial of tivantinib in combination with sorafenib in adult patients with advanced solid tumors

PURPOSE

This phase I study evaluated the safety, tolerability, maximum tolerated dose (MTD), and recommended phase II dose (RP2D) of tivantinib combined with sorafenib in patients with advanced solid tumors.

MATERIALS AND METHODS

A standard 3 + 3 dose escalation design was used. At the RP2D, expansion cohorts in 5 tumor types could be enrolled. Pharmacogenetic and pharmacodynamic analysis were performed.

RESULTS

Eighty-seven patients received the study treatment. The combination had no unexpected toxicities. The most common treatment-related adverse events (AE) were rash (40 %), diarrhea (38 %), and anorexia (33 %). The RP2D was tivantinib 360 mg BID and sorafenib 400 mg BID for all cancer histologies, except in hepatocellular carcinoma (HCC) patients tivantinib was 240 mg BID plus sorafenib 400 mg BID. The overall response rate was 12 % in all patients, 26 % in melanoma, 15 % in renal cell carcinoma (RCC), 10 % in HCC, and 0 % in other patients. Disease control rate (CR, PR and SD ≥8 weeks) was 58 % in all patients, 90 % in RCC, 65 % in HCC, 63 % in melanoma, 40 % in breast cancer, and 8 % in NSCLC patients.

CONCLUSIONS

The combination treatment could be administered at full standard single-agent doses in all patients except those with HCC, where tivantinib was lowered to 240 mg BID. Preliminary evidence of anticancer activity was observed in patients with RCC, HCC, and melanoma, including patients refractory to sorafenib and/or other anti-VEGF pathway therapies. The combination treatment has therapeutic potential in treating a variety of solid tumors.

First-In-Human Phase I Study of a Next-Generation, Oral, TGFβ Receptor 1 Inhibitor, LY3200882, in Patients with Advanced Cancer

PURPOSE

A novel, selective, next-generation transforming growth factor beta (TGFβ) receptor type-1 small molecule inhibitor, LY3200882, demonstrated promising preclinical data. This first-in-human trial evaluated safety, tolerability, recommended phase II dose (RP2D), pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of LY3200882 as monotherapy or with other anticancer agents in patients with advanced cancer.

PATIENTS AND METHODS

This phase I multicenter study of oral LY3200882 (NCT02937272) comprised dose escalation, monotherapy expansion in grade 4 glioma, and combination therapy in solid tumors (LY3200882 and PD-L1 inhibitor LY3300054), pancreatic cancer (LY3200882, gemcitabine, and nab-paclitaxel), and head and neck squamous cell cancer (LY3200882, cisplatin, and radiation).

RESULTS

Overall, 139 patients with advanced cancer were treated. The majority (93.5%) of patients experienced ≥1 treatment-emergent adverse events (TEAE), with 39.6% LY3200882-related. Grade 3 LY3200882-related toxicities were only observed in combination therapy arms. One patient in the pancreatic cancer arm experienced cardiovascular toxicity. The LY3200882 monotherapy RP2Ds were established in two schedules: 50 mg twice a day 2-weeks-on/2-weeks-off and 35 mg twice a day 3-weeks-on/1-week-off. Four patients with grade 4 glioma had durable Revised Assessment in Neuro Oncology (RANO) partial responses (PR) with LY3200882 monotherapy (n = 3) or LY3200882-LY3300054 combination therapy (n = 1). In treatment-naïve patients with advanced pancreatic cancer, 6 of 12 patients achieved Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 PR and 3 of 12 patients demonstrated stable disease, for an overall 75% disease-control rate with the combination of LY3200882, gemcitabine, and nab-paclitaxel.

CONCLUSIONS

LY3200882 as monotherapy and combination therapy was safe and well tolerated with preliminary antitumor activity observed in pancreatic cancer. Further studies to evaluate the efficacy of LY3200882 with gemcitabine and nab-paclitaxel in advanced pancreatic cancer are warranted.

NKG2A expression identifies a subset of human Vδ2 T cells exerting the highest antitumor effector functions

Human Vδ2 cells are innate-like γδ T effectors performing potent immune surveillance against tumors. The constitutive expression of NKG2A identifies a subset of Vδ2 T cells licensed with an intrinsic hyper-responsiveness against cancer. Indeed, the transcriptomic profiles of NKG2A⁺ and NKG2A^- cells characterize two distinct "intralineages" of Vδ2 T lymphocytes that appear early during development, keep their phenotypes, and show self-renewal capabilities in adult life. The hyper-responsiveness of NKG2A⁺ Vδ2 T cells is counterbalanced by the inhibitory signaling delivered by human leukocyte antigen E (HLA-E) expressed on malignant cells as a tumor-escape mechanism. However, either masking or knocking out NKG2A restores the capacity of Vδ2 T cells to exert the highest effector functions even against HLA-E⁺ tumors. This is highly relevant in the clinic, as the different degrees of engagement of the NKG2A-HLA-E checkpoint in hepatocellular carcinoma, glioblastoma, and non-small cell lung cancer directly impact patients' overall survival. These findings open avenues for developing combined cellular and immunologic anticancer therapies.

Pembrolizumab Activity in Recurrent High-Grade Gliomas with Partial or Complete Loss of Mismatch Repair Protein Expression: A Monocentric, Observational and Prospective Pilot Study

INTRODUCTION

Pembrolizumab demonstrated promising results in hypermutated tumors of diverse origin. Immunohistochemical loss of mismatch repair (MMR) proteins has been suggested as a surrogate of hypermutation in high-grade gliomas (HGG). We evaluated the efficacy and safety of pembrolizumab in relapsing HGGs with immunohistochemical loss of at least 1 MMR protein. Molecular biomarkers of pembrolizumab activity were also analyzed.

METHODS

Consecutive patients with recurrent HGG and partial or complete loss of MMR protein expression were prospectively enrolled; they received pembrolizumab 200 mg once every 3 weeks until disease progression. The primary endpoint was disease control rate (DCR). Post hoc exploratory analyses included next-generation sequencing to assess tumor mutational burden (TMB), and immunostaining for CD8+ T-cells and CD68+ macrophages.

RESULTS

Among 310 HGG patients screened, 13 cases with MMR loss were enrolled: eight glioblastoma, four anaplastic astrocytoma, and one anaplastic oligodendroglioma. Median age was 43 years. DCR was 31%: four patients had stable disease and no patient had complete or partial response. TMB ranged between 6.8 and 23.4 mutations/megabase. Neither TMB nor gene mutations, nor CD8+ T-cell and CD68+ macrophage content, were associated with pembrolizumab activity.

CONCLUSIONS

pembrolizumab showed no apparent benefit in these patients. No molecular biomarker was found to be associated with pembrolizumab activity.

Is supratotal resection achievable in low-grade gliomas? Feasibility, putative factors, safety, and functional outcome

OBJECTIVE

Surgery for low-grade gliomas (LGGs) aims to achieve maximal tumor removal and maintenance of patients' functional integrity. Because extent of resection is one of the factors affecting the natural history of LGGs, surgery could be extended further than total resection toward a supratotal resection, beyond tumor borders detectable on FLAIR imaging. Supratotal resection is highly debated, mainly due to a lack of evidence of its feasibility and safety. The authors explored the intraoperative feasibility of supratotal resection and its short- and long-term impact on functional integrity in a large cohort of patients. The role of some putative factors in the achievement of supratotal resection was also studied.

METHODS

Four hundred forty-nine patients with a presumptive radiological diagnosis of LGG consecutively admitted to the neurosurgical oncology service at the University of Milan over a 5-year period were enrolled. In all patients, a policy was adopted to perform surgery according to functional boundaries, aimed at achieving a supratotal resection whenever possible, without any patient or tumor a priori selection. Feasibility, general safety, and tumor or patient putative factors possibly affecting the achievement of a supratotal resection were analyzed. Postsurgical patient functional performance was evaluated in five cognitive domains (memory, language, praxis, executive functions, and fluid intelligence) using a detailed neuropsychological evaluation and quality of life (QOL) examination.

RESULTS

Total resection was feasible in 40.8% of patients, and supratotal resection in 32.3%. The achievement of a supratotal versus total resection was independent of age, sex, education, tumor volume, deep extension, location, handedness, appearance of tumor border, vicinity to eloquent sites, surgical mapping time, or surgical tools applied. Supratotal resection was associated with a long clinical history and histological grade II, suggesting that reshaping of brain networks occurred. Although a consistent amount of apparently MRI-normal brain was removed with this approach, the procedure was safe and did not carry additional risk to the patient, as demonstrated by detailed neuropsychological evaluation and QOL examination. This approach also improved seizure control.

CONCLUSIONS

Supratotal resection is feasible and safe in routine clinical practice. These results show that a long clinical history may be the main factor associated with its achievement.

Ectopic lingual thyroid as unusual cause of severe dysphagia

Ectopic lingual thyroid is an uncommon embryological aberration characterized by the presence of thyroid tissue located in a site different from the pretracheal region as in the normal. Lingual thyroid is the most frequent ectopic location of the thyroid gland, although its clinical incidence varies between 1:3000 and 1:10,000. We present the case of a 26-year-old woman who presented severe dysphagia caused by a mass located on the base of the tongue in the midline. An endoscopic partial removal of the ectopic tissue allowed her to rapidly regain her swallowing capacity. The literature regarding the incidence and diagnosis of lingual thyroid is reviewed and the possibilities of treatment discussed.

Vinorelbine in pemetrexed-pretreated patients with malignant pleural mesothelioma

BACKGROUND

Pemetrexed-platinum chemotherapy is the standard first-line treatment of unresectable malignant pleural mesothelioma (MPM). At progression, patients are generally selected to experimental trials, when available, or, in every-day clinical practice, they are offered second-line chemotherapy. The optimal treatment has not yet been defined. The aim of this retrospective, single-center study was to evaluate the activity and toxicity of vinorelbine administered to a consecutive series of pemetrexed-pretreated MPM patients.

METHODS

Vinorelbine 25 mg/m(2) was administered intravenously as a single agent on days 1, 8 every three weeks, either as second-line (2L) or further-line (>2L) therapy. Treatment was repeated for a maximum of 6 cycles, until progression, or unacceptable toxicity.

RESULTS

Fifty-nine patients were included in this analysis. Vinorelbine was given to 34 patients as 2L, and to 25 as > 2L treatment. The median age was 69 years (range 45-80). Forty-two patients (71.2%) had a good EORTC prognostic score. Partial response was observed in 9 (15.2%) cases, stable disease in 20 (33.9%). The overall disease control rate (DCR) was 49.1%. Median progression-free survival (PFS) and overall survival (OS) were 2.3 and 6.2 months, respectively. ECOG performance status (PS) (HR(0 vs. 1-2) 0.50; 95%CI: 0.3-0.8; p = 0.014) and PFS ≥ 6 months following first-line (FL) chemotherapy (HR(FL-PFS>6 ms vs. <6 ms) 0.50; 95%CI: 0.3-0.9; p = 0.031) were significantly associated to OS in multivariate analysis. No difference was observed in terms of DCR, PFS, and OS in relation to age, histology, sex, line of vinorelbine therapy, or response to FL treatment. Hematological toxicity was acceptable, with grade 3/4 neutropenia occurring in 5 (8.4%) patients, and there were no cases of febrile neutropenia. The main non-hematological toxicities were grade 2 fatigue in 17 (28.8%) and constipation in 7 (11.8%) patients.

CONCLUSIONS

Vinorelbine was moderately active in pemetrexed-pretreated MPM patients, with an acceptable toxicity profile, particularly in patients with ECOG-PS0 and FL-PFS ≥ 6 months.

Investigation on the role of integrated PET/MRI for target volume definition and radiotherapy planning in patients with high grade glioma

PURPOSE

To evaluate the impact of fluid-attenuated-inversion-recovery MRI (FLAIR/MRI) and Carbon-11-labeled-methionine PET (11C-MET-PET) on high grade glioma (HGG) tumor volume delineation for radiotherapy planning.

MATERIAL AND METHODS

Sixty-nine patients with HGG were evaluated. The clinical target volumes (CTV1, generated by adding a 10mm margin to FLAIRMRI area, CTV2 by adding a 20mm margin to enhanced T1MRI) and biological target volume (BTV) were delineated on pre-operative MRI images and 11CMETPET respectively.

RESULTS

The overlap between CTV1 and CTV2 showed a low correlation between the two volumes with CTV1 not always fully included into the CTV2. In all cases the whole BTV was included into the CTV1, while in 35/69 patients (50%) part of BTV was outside the CTV2 despite larger margins were added. In all cases recurrences were within the CTV1 volume and in 19/38 (50%) partially outside the CTV2. In all patients relapse corresponded to the BTV area.

CONCLUSIONS

Our data suggest that the target volume definition using FLAIR-MRI is more adequate compared to enhanced T1MRI. 11C-METPET uptake could help identify microscopic residual areas.

Phase I study of PF-03446962, a fully human monoclonal antibody against activin receptor-like kinase-1, in patients with hepatocellular carcinoma

BACKGROUND

This expansion cohort of a multicenter, dose-escalation, phase I study (NCT00557856) evaluated safety, tolerability, antitumor activity, pharmacokinetics, and pharmacodynamic effects of the anti-activin receptor-like kinase-1 (ALK-1) monoclonal antibody PF-03446962 in advanced hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

Patients with HCC and disease progression after prior antiangiogenic therapy or intolerance to treatment received PF-03446962 7 mg/kg intravenously biweekly, as recommended in the dose-escalation part of the study.

RESULTS

Twenty-four patients received PF-03446962. The most frequent treatment-related adverse events (AEs) were thrombocytopenia (33.3%), asthenia (29.2), and chills (16.7%). Two patients experienced treatment-related telangiectasia, suggesting an in vivo knockout of ALK-1 function through ALK-1 pathway inhibition. Overall, treatment-related grade 3-4 AEs were reported in eight patients (33.3%). Treatment-related grade 3-4 thrombocytopenia was noted in four patients. No complete or partial responses were reported. Twelve (50%) patients achieved stable disease, which lasted ≥12 weeks in seven (29.2%) patients. The median time to progression was 3 months. Biomarker analyses showed higher mean tumor expression of c-tumor mesenchymal-epithelial transition factor and higher mean serum levels of bone morphogenetic protein-9 in patients with disease control (DC) for ≥12 weeks versus patients with disease progression. Conversely, lower mean serum transforming growth factor-β and vascular endothelial growth factor receptor-3 levels were detected in patients with DC versus patients with progression.

CONCLUSIONS

The observed safety, tolerability, pharmacokinetic profile, and clinical activity support further evaluation of PF-03446962 in patients with HCC and other solid malignancies, as single agent or in combination with other antiangiogenic, chemotherapeutic, or immunotherapeutic agents.

TRIAL REGISTRATION NUMBER

NCT00557856.

Reproducibility of the WHO classification of thymomas: practical implications

BACKGROUND

The WHO-classification was shown to be an independent prognostic marker in some but not all retrospective studies possibly due to lack of reproducibility. We investigated the reproducibility of the WHO-classification and its prognostic implication using a large series of resected thymomas.

METHODS

Four independent pathologists histologically classified a surgical series of 129 thymic tumors in a blinded fashion. Fleiss' kappa-coefficient was used to assess the pathologists' overall agreement, and Cohen-Kappa to assess the agreement between two observers. Disease-related-survival (DRS) and progression-free-survival (PFS) curves were generated by Kaplan-Meier method and compared by log-rank test.

RESULTS

In 63/129 (48.8%) cases there was a complete agreement; in 43/129 (33.3%) cases 3/4 pathological diagnoses were identical; in 15/129 (11.6%) cases the diagnoses were identical by pair; in 8/129 (6.2%) cases three different pathological diagnoses were on record. The Kappa-correlation coefficient was only moderate (0.53). A following web review carried out on the 23 cases with at least two different diagnoses reached a complete consensus. The histotype showed a statistically significant impact on PFS and DRS in the classification provided by only two pathologists.

CONCLUSIONS

In this study, the agreement on WHO classification of thymomas was only moderate and this impacted on patients management. Web consensus conference on the diagnosis, more stringent diagnostic criteria or the adoption of referral diagnostic centres may substantially reduce discrepancies.

Pathological characterization of nivolumab-related liver injury in a patient with glioblastoma

Immune checkpoint inhibitors such as anti-CTLA-4 and anti-PD-1/PD-L1 monoclonal antibodies have dramatically changed the paradigm of cancer therapy over the past few years. The use of these agents is associated with a unique pattern of autoimmune-like/inflammatory side effects termed immune-related adverse events (irAEs), that may cause collateral damage to normal tissues. Although severe irAEs remain rare, they can become life-threatening if not anticipated and managed appropriately. Improving our knowledge of the mechanisms underlying the development of these toxicities is crucial to optimize clinical efficacy and safety of these new immunotherapeutics. Herein we describe for the first time the pathological features of a severe liver-injury associated with the administration of the anti-PD-1 agent nivolumab in a patient with glioblastoma.