Phase III, multicenter, randomized trial of 45 Gy versus 30 Gy thoracic radiation for extensive-stage small cell lung cancer (ES-SCLC): Study protocol.

BACKGROUND: Consolidative thoracic radiotherapy (cTRT) has previously shown benefit to patients with extensive stage small cell lung cancer (ES-SCLC) who respond to chemotherapy. However, the optimum dose of cTRT is unknown. The purpose of this randomized trial is to compare the efficacy of 45 Gy in 15 fractions with 30 Gy in 10 fractions cTRT in ES-SCLC. METHODS: This phase III, multicenter, randomized trial is designed to evaluate the safety and efficacy of different cTRT dose in ES-SCLC. Eligible patients with pathologically confirmed ES-SCLC who responded to 4-6 cycles of etoposide plus cisplatin (EP) or carboplatin (EC) chemotherapy were randomized 1:1 to receive either 30 Gy in 10 fractions (standard dose) or 45 Gy in 15 fractions (high dose) cTRT. The primary endpoint is 2-year overall survival (OS). Secondary endpoints include 2-year progression-free survival (PFS), 2-year local control (LC) and treatment related toxicity as measured by adverse events according to the Common Terminology Criteria for Adverse Events (version 4.0). DISCUSSION: The present study is the first randomized phase III trial designed to evaluate the efficacy of higher versus lower dose cTRT in ES-SCLC, providing evidence for future clinical practice in prolonging survival of patients with ES-SCLC.

Improved Cancer-Specific Risk Stratification by the Lymph Node Ratio-Based Nomogram: A Potential Role in Guiding Postoperative Management Decisions for Oral Cavity Carcinoma.

PURPOSE: To develop and validate a nomogram integrating lymph node ratio (LNR) to predict cancer-specific survival (CSS) and assist decision making for postoperative management in nonmetastatic oral cavity squamous cell carcinoma (OCSCC). MATERIALS AND METHODS: We retrospectively retrieved 6,760 patients with OCSCC primarily treated with surgery from surveillance, epidemiology, and end results database between 2010 and 2015. They were randomly divided into training and validation cohorts. Performance of the nomogram was evaluated by calibration curve, consistency index, area under the curve, and decision curve analysis and was compared with that of the LNR, positive lymph nodes (PLN) and tumor node metastasis (TNM) staging. According to the individualized nomogram score, patients were classified into three risk cohorts. The therapeutic efficacy of postoperative radiotherapy and chemotherapy was evaluated in each cohort. RESULTS: The nomogram incorporated six independent variables, including race, tumor site, grade, T stage, PLN, and LNR. Calibration plots demonstrated a good match between the predicted and observed CSS. C-indices for training and validation cohorts were 0.746 (95% CI, 0.740 to 0.752) and 0.726 (95% CI, 0.713 to 0.739), compared with 0.687, 0.695, and 0.669 for LNR, PLN, and TNM staging, respectively (P < .001). Decision curve analyses confirmed that nomogram showed the best performance in clinical utility. Postoperative radiotherapy presented survival benefit in medium-and high-risk groups but showed a negative effect in the low-risk group. Chemotherapy was only beneficial in the high-risk group. CONCLUSION: The LN status-incorporated nomogram demonstrated good discrimination and predictive accuracy of CSS for patients with OCSCC and could identify those most likely to benefit from adjuvant therapy.

Spatial architecture of regulatory T-cells correlates with disease progression in patients with nasopharyngeal cancer.

Purpose: This study aims to investigate the prognostic value of composition and spatial architecture of tumor-infiltrating lymphocytes (TILs) as well as PDL1 expression on TILs subpopulations in nasopharyngeal carcinoma (NPC). Methods: A total of 121 patients with NPC were included and divided into two groups: favorable (n = 68) and unfavorable (n = 53). The archived tumor tissues of the included patients were retrieved, and a tissue microarray was constructed. The density and spatial distribution of TILs infiltration were analyzed using the multiplex fluorescent immunohistochemistry staining for CD3, CD4, CD8, Foxp3, cytokeratin (CK), PDL1, and 4',6-diamidino-2-phenylindole (DAPI). The infiltration density of TILs subpopulations and PDL1 expression were compared between the two groups. The Gcross function was calculated to quantify the relative proximity of any two types of cells. The Cox proportional hazards regression model was used to identify factors associated with overall survival (OS) and disease-free survival (DFS). Results: The densities of regulatory T-cells (Tregs), effector T-cells (Teffs), PDL1+ Tregs, and PDL1+ Teffs were significantly higher in patients with unfavorable outcomes. PDL1 expression on tumor cells (TCs) or overall TILs was not associated with survival. Multivariate analysis revealed that higher PDL1+ Tregs infiltration density was independently associated with inferior OS and DFS, whereas Tregs infiltration density was only a prognostic marker for DFS. Spatial analysis revealed that unfavorable group had significantly stronger Tregs and PDL1+ Tregs engagement in the proximity of TCs and cytotoxic T lymphocyte (CTLs). Gcross analysis further revealed that Tregs and PDL1+ Tregs were more likely to colocalize with CTLs. Moreover, increased GTC : Treg (Tregs engagement surrounding TCs) and GCTL : PDL1+ Treg were identified as independent factors correlated with poor outcomes. Conclusion: TILs have a diverse infiltrating pattern and spatial distribution in NPC. Increased infiltration of Tregs, particularly PDL1+ Tregs, as well as their proximity to TCs and CTLs, correlates with unfavorable outcomes, implying the significance of intercellular immune regulation in mediating disease progression.

Lymph node ratio-dependent prognosis stratification and postoperative radiotherapy utilization in T1-2N1 oral cavity carcinoma.

OBJECTIVE: Pathological T1-2N1 oral cavity squamous cell carcinoma (pT1-2N1 OCSCC) is a setting with intermediate prognosis whilst without consensus regarding the utilization of postoperative radiotherapy (PORT). This study aimed to investigate the prognostic value of lymph node ratio (LNR) and to further examine its clinical validity for guiding PORT in pT1-2N1 OCSCC. METHODS: OCSCC patients who received surgery between 2010 and 2015 with at least 6 lymph nodes dissection were extracted from the Surveillance, Epidemiology and End Results (SEER) database. Time-dependent receiver operating characteristic (ROC) analysis was used to identify the optimal cutoff of LNR. Multivariable Cox regression analysis was employed to assess the prognostic value of LNR. Impact of PORT was evaluated in respective subgroups stratified by LNR. RESULTS: A total of 870 OCSCC patients with pT1-2N1 diseases were eligible for analysis. The 5-year overall survival (OS) and disease-specific survival (DSS) was 57.2% and 67.9% respectively. Time-dependent ROC analyses for OS and DSS concordantly revealed 5.5% as the optimal cutoff of LNR. Significantly higher risks of death (HR = 1.610, 95% CI: 1.139-2.276) and disease-specific death (HR = 1.731, 95% CI: 1.101-2.723) were unveiled in patients with LNR > 5.5%. PORT related improvement on OS (5-year rate: 57.6% vs. 47.3%, p = 0.095) and DSS (5-year rate: 71.0% vs. 53.8%, p = 0.030) was only found in LNR > 5.5% subgroup. CONCLUSIONS: LNR > 5.5% is indicative of inferior outcome in pT1-2N1 OCSCC, warranting the utilization of PORT in this sub-setting.

Lymph node ratio-based nomogram for prognosis evaluation and treatment optimization of non-metastatic oral cavity squamous cell carcinoma.

BACKGROUND: Lymph node ratio (LNR) has been increasingly reported as a prognostic factor in oral cavity squamous cell carcinoma (OCSCC). This study aimed to develop and validate a prognostic nomogram integrating LNR and to further assess its role in guiding adjuvant therapy for OCSCC. METHODS: A total of 8703 OCSCC patients treated primarily with surgery in the Surveillance, Epidemiology and End Results (SEER) database were retrieved and randomly divided into training and validation cohorts. The nomogram was created based on the factors identified by Cox model. The value of PORT and chemotherapy was respectively evaluated in each prognostic group according to nomogram-deduced individualized score. RESULTS: The final nomogram included tumor site, grade, T stage, number of positive lymph nodes and LNR. Calibration plots demonstrated a good match between predicted and observed rates of overall survival (OS). The concordance indexes for training and validation cohorts were 0.720 (95% confidence interval (CI): 0.708, 0.732) and 0.711 (95% CI: 0.687, 0.735), both significantly higher than did TNM stage (p< 0.001). According to individualized nomogram score, patients were stratified into three subgroups with significantly distinct outcome. PORT presented survival benefit among medium- and high-risk groups whereas a near-detrimental effect in low-risk group. Chemotherapy was found to be beneficial only in high-risk group. CONCLUSION: This LNR-incorporated nomogram surpassed the conventional TNM stage in predicting prognosis of patients with non-metastatic OCSCC and identified sub-settings that could gain survival benefit from adjuvant thearpy.

Management of cervical aortic arch complicated by multiple aneurysms.

OBJECTIVES: Cervical aortic arch with aneurysm formation is considered an extremely rare condition. Here, we summarize our experience in treating 8 patients. We validated extra-anatomic ascending-to-infrarenal abdominal aorta bypass through the retroperitoneal cavity without circulatory arrest as an alternative treatment for patients with a tortuous arch that was unsuitable for endovascular repair. METHODS: From March 2015 to April 2018, 8 patients (7 women; median age 46 years) diagnosed with cervical aortic arch complicated with aneurysm formation were treated at Peking Union Medical College Hospital and the Affiliated Hospital of Qingdao University. After assessment of the anatomical characteristics, 4 patients underwent endovascular repair. Three patients with a tortuous aortic arch and saccular aneurysm formation between the left common carotid artery and the left subclavian artery were treated with an extra-anatomic ascending-to-infrarenal abdominal aorta bypass and aneurysm indwelling. One patient refused surgical intervention and is being followed up on a yearly basis at our outpatient clinic. No circulatory arrest was required during surgery. RESULTS: No severe postoperative complications were observed during follow-up (6-36 months). Postoperative computed tomography angiography revealed patent blood flow in the prosthetic aortic graft bypass. No endoleak, migration or stenosis of the stent grafts was observed in patients following endovascular repair. The left subclavian artery was preserved in 3 patients. Follow-up computed tomography angiography revealed satisfactory postoperative results in all patients, with no signs of aortic dilation or coarctation. CONCLUSIONS: Ascending-to-infrarenal abdominal aorta bypass through the retroperitoneal cavity is a safe and effective treatment for cervical aortic arch with a tortuous aorta complicated by aneurysm formation and coarctation.

T cell receptor richness in peripheral blood increases after cetuximab therapy and correlates with therapeutic response.

The role of T cell receptor (TCR) signaling for adaptive immune responses is essential. The ability to respond to a broad spectrum of tumor antigens requires an adaptive selection of various TCR. So far, little is known about the role of TCR richness and clonality in the cellular immune response to head and neck cancer (HNC), though the Endothelial Growth Factor Receptor (EGFR)-specific CD8+ T cell response can be enhanced by cetuximab therapy. Therefore, we investigated differences in TCR sequences between human papillomavirus (HPV)+ and HPV- HNC patients, as well as differences in TCR sequence characteristics between T cells of peripheral blood mononuclear cells (PBMC) and tumor infiltrating lymphocytes (TIL). Additionally, we were able to investigate the TCR richness and clonality in samples pre- and post- treatment in a prospective clinical trial of neoadjuvant cetuximab. Interestingly, HPV+ and HPV- HNSCC did not significantly differ in the extent of TCR clonality and richness in PBMC or TIL. However, neoadjuvant cetuximab treatment increased the number of unique TCR sequences in PBMC (p = 0.0003), which was more prominent in the clinical responder patients compared to non-responders (p = 0.04). A trend toward TCR gene focusing was observed in TIL (p = 0.1) post-treatment. Thus, an increase in richness of TCR sequences in the periphery with a focusing at the tumor site is associated with an improved treatment response, suggesting an influence of peripheral quantity and intratumoral quality on adaptive immunity in cetuximab treated patients.

Novel Effector Phenotype of Tim-3+ Regulatory T Cells Leads to Enhanced Suppressive Function in Head and Neck Cancer Patients.

Purpose: Regulatory T (Treg) cells are important suppressive cells among tumor-infiltrating lymphocytes (TIL). Treg cells express the well-known immune checkpoint receptor PD-1, which is reported to mark "exhausted" Treg with lower suppressive function. T-cell immunoglobulin mucin (Tim)-3, a negative regulator of Th1 immunity, is expressed by a sizeable fraction of TIL Tregs, but the functional status of Tim-3+ Tregs remains unclear.Experimental Design: CD4+CTLA-4+CD25high Treg cells were sorted from freshly excised head and neck squamous cell carcinoma (HNSCC) TIL based on Tim-3 expression. Functional and phenotypic features of these Tim-3+ and Tim-3- TIL Tregs were tested by in vitro suppression assays and multi-color flow cytometry. Gene-expression profiling and NanoString analysis of Tim-3+ TIL Treg were performed. A murine HNSCC tumor model was used to test the effect of anti-PD-1 immunotherapy on Tim-3+ Treg.Results: Despite high PD-1 expression, Tim-3+ TIL Treg displayed a greater capacity to inhibit naïve T-cell proliferation than Tim-3- Treg. Tim-3+ Treg from human HNSCC TIL also displayed an effector-like phenotype, with more robust expression of CTLA-4, PD-1, CD39, and IFN-γ receptor. Exogenous IFN-γ treatment could partially reverse the suppressive function of Tim-3+ TIL Treg. Anti-PD-1 immunotherapy downregulated Tim-3 expression on Tregs isolated from murine HNSCC tumors, and this treatment reversed the suppressive function of HNSCC TIL Tregs.Conclusions: Tim-3+ Treg are functionally and phenotypically distinct in HNSCC TIL, and are highly effective at inhibiting T-cell proliferation despite high PD-1 expression. IFN-γ induced by anti-PD-1 immunotherapy may be beneficial by reversing Tim-3+ Treg suppression. Clin Cancer Res; 24(18); 4529-38. ©2018 AACR.

STING activation enhances cetuximab-mediated NK cell activation and DC maturation and correlates with HPV+ status in head and neck cancer.

OBJECTIVES: The intracellular DNA sensor stimulator of interferon genes (STING) has recently been shown to play a vital role in anti-viral and anti-tumor immune responses stimulating cytokine production. While human papillomavirus (HPV) is a causative agent for a subset of head and neck squamous cell carcinoma (HNSCC) with unique etiology and clinical outcome, how the STING pathway is regulated in a virus-induced tumor microenvironment is not well understood. Since STING inactivation likely reflects immunoescape via innate immunity, we hypothesized that its restoration would improve efficacy of the immune modulatory monoclonal antibody (mAb), cetuximab. MATERIALS AND METHODS: We correlated STING protein expression with clinical parameters by immunohistochemistry (n = 106) and its mRNA expression from The Cancer Genome Atlas (TCGA) in HNSCC tissue specimens. STING protein expression was tested for association with cancer-specific survival (CSS). We further examined the impact of STING activation on cetuximab-mediated immunity using an in vitro NK:DC:tumor cells co-culture system. RESULTS: In this study, we found that expression of STING both at the protein and mRNA level was higher in HPV positive (HPV+) specimens but unrelated to TNM stage or cancer-specific survival. Our in vitro studies verified that STING activation enhanced cetuximab mediated NK cell activation and DC maturation. CONCLUSION: Our findings suggest a novel role of STING in HPV-related carcinogenesis, in which activation of the STING signaling pathway may facilitate anti-tumor response in HNSCC patients, particularly in combination with therapeutic monoclonal antibodies (mAbs) such as cetuximab, an epidermal growth factor receptor (EGFR) inhibitor.

Phase Ib Study of Immune Biomarker Modulation with Neoadjuvant Cetuximab and TLR8 Stimulation in Head and Neck Cancer to Overcome Suppressive Myeloid Signals.

Purpose: The response rate of patients with head and neck squamous cell carcinoma (HNSCC) to cetuximab therapy is only 15% to 20%, despite frequent EGFR overexpression. Because immunosuppression is common in HNSCC, we hypothesized that adding a proinflammatory TLR8 agonist to cetuximab therapy might result in enhanced T-lymphocyte stimulation and anti-EGFR-specific priming.Experimental Design: Fourteen patients with previously untreated HNSCC were enrolled in this neoadjuvant trial and treated preoperatively with 3 to 4 weekly doses of motolimod (2.5 mg/m2) and cetuximab. Correlative tumor and peripheral blood specimens were obtained at baseline and at the time of surgical resection and analyzed for immune biomarker changes. Preclinical in vitro studies were also performed to assess the effect of cetuximab plus motolimod on myeloid cells.Results: TLR8 stimulation skewed monocytes toward an M1 phenotype and reversed myeloid-derived suppressor cell (MDSC) suppression of T-cell proliferation in vitro These data were validated in a prospective phase Ib neoadjuvant trial, in which fewer MDSC and increased M1 monocyte infiltration were found in tumor-infiltrating lymphocytes. Motolimod plus cetuximab also decreased induction of Treg and reduced markers of suppression, including CTLA-4, CD73, and membrane-bound TGFß. Significantly increased circulating EGFR-specific T cells were observed, concomitant with enhanced CD8+ T-cell infiltration into tumors. These T cells manifested increased T-cell receptor (TCR) clonality, upregulation of the costimulatory receptor CD27, and downregulation of inhibitory receptor TIGIT.Conclusions: Enhanced inflammatory stimulation in the tumor microenvironment using a TLR agonist overcomes suppressive myeloid and regulatory cells, enhancing the cellular antitumor immune response by therapeutic mAb in HNSCC. Clin Cancer Res; 24(1); 62-72. ©2017 AACR.

PD-1 Status in CD8+ T Cells Associates with Survival and Anti-PD-1 Therapeutic Outcomes in Head and Neck Cancer.

Improved understanding of expression of immune checkpoint receptors (ICR) on tumor-infiltrating lymphocytes (TIL) may facilitate more effective immunotherapy in head and neck cancer (HNC) patients. A higher frequency of PD-1+ TIL has been reported in human papillomavirus (HPV)+ HNC patients, despite the role of PD-1 in T-cell exhaustion. This discordance led us to hypothesize that the extent of PD-1 expression more accurately defines T-cell function and prognostic impact, because PD-1high T cells may be more exhausted than PD-1low T cells and may influence clinical outcome and response to anti-PD-1 immunotherapy. In this study, PD-1 expression was indeed upregulated on HNC patient TIL, and the frequency of these PD-1+ TIL was higher in HPV+ patients (P = 0.006), who nonetheless experienced significantly better clinical outcome. However, PD-1high CD8+ TILs were more frequent in HPV- patients and represented a more dysfunctional subset with compromised IFN-γ secretion. Moreover, HNC patients with higher frequencies of PD-1high CD8+ TIL showed significantly worse disease-free survival and higher hazard ratio for recurrence (P < 0.001), while higher fractions of PD-1low T cells associated with HPV positivity and better outcome. In a murine HPV+ HNC model, anti-PD-1 mAb therapy differentially modulated PD-1high/low populations, and tumor rejection associated with loss of dysfunctional PD-1high CD8+ T cells and a significant increase in PD-1low TIL. Thus, the extent of PD-1 expression on CD8+ TIL provides a potential biomarker for anti-PD-1-based immunotherapy. Cancer Res; 77(22); 6353-64. ©2017 AACR.

Interferon-γ Drives Treg Fragility to Promote Anti-tumor Immunity.

Regulatory T cells (Tregs) are a barrier to anti-tumor immunity. Neuropilin-1 (Nrp1) is required to maintain intratumoral Treg stability and function but is dispensable for peripheral immune tolerance. Treg-restricted Nrp1 deletion results in profound tumor resistance due to Treg functional fragility. Thus, identifying the basis for Nrp1 dependency and the key drivers of Treg fragility could help to improve immunotherapy for human cancer. We show that a high percentage of intratumoral NRP1+ Tregs correlates with poor prognosis in melanoma and head and neck squamous cell carcinoma. Using a mouse model of melanoma where Nrp1-deficient (Nrp1-/-) and wild-type (Nrp1+/+) Tregs can be assessed in a competitive environment, we find that a high proportion of intratumoral Nrp1-/- Tregs produce interferon-γ (IFNγ), which drives the fragility of surrounding wild-type Tregs, boosts anti-tumor immunity, and facilitates tumor clearance. We also show that IFNγ-induced Treg fragility is required for response to anti-PD1, suggesting that cancer therapies promoting Treg fragility may be efficacious.

Adaptive resistance to anti-PD1 therapy by Tim-3 upregulation is mediated by the PI3K-Akt pathway in head and neck cancer.

Programmed Death 1 (PD-1) and T cell Ig and mucin domain-3 protein (Tim-3) are immune checkpoint receptors that are expressed on tumor-infiltrating lymphocytes (TIL) in tumor-bearing mice and humans. As anti-PD-1 single agent response rates are only <20% in head and neck squamous cell carcinoma (HNSCC) patients, it is important to understand how multiple inhibitory checkpoint receptors maintain suppressed cellular immunity. One such receptor, Tim-3, activates downstream proliferative pathways through Akt/S6, and is highly expressed in dysfunctional TIL. We observed that PD-1 and Tim-3 co-expression was associated with a more exhausted phenotype, with the highest PD-1 levels on TIL co-expressing Tim-3. Dampened Akt/S6 phosphorylation in these PD-1+Tim-3+ TIL, when the PD-1 pathway was ligated, suggested that signaling cross-talk could lead to escape through Tim-3 expression. Indeed, PD-1 blockade of human HNSCC TIL led to further Tim-3 upregulation, supporting a circuit of compensatory signaling and potentially permitting escape from anti-PD-1 blockade in the tumor microenvironment. Also, in a murine HNC tumor model that is partially responsive to anti-PD-1 therapy, Tim-3 was upregulated in TIL from persistently growing tumors. Significant antitumor activity was observed after sequential addition of anti-Tim-3 mAb to overcome adaptive resistance to anti-PD-1 mAb. This increased Tim-3-mediated escape of exhausted TIL from PD-1 inhibition that was mediated by phospho-inositol-3 kinase (PI3K)/Akt complex downstream of TCR signaling but not cytokine-mediated pathways. Taken together, we conclude that during PD-1 blockade, TIL upregulate Tim-3 in a PI3K/Akt-dependent manner, providing further support for dual targeting of these molecules for more effective cancer immunotherapy.

Tumor-infiltrating Tim-3+ T cells proliferate avidly except when PD-1 is co-expressed: Evidence for intracellular cross talk.

Programmed Death 1 (PD-1) and T cell Ig and mucin domain-3 protein (Tim-3) are immune checkpoint receptors highly expressed on tumor infiltrating T lymphocytes (TIL). PD-1 inhibits T cell activation and type-1 T cell responses, while Tim-3 is proposed to mark more extensively exhausted cells, although the mechanisms underlying Tim-3 function are not clear. Trials of anti-PD-1 therapy have identified a large subset of non-responder patients, likely due to expression of alternative checkpoint molecules like Tim-3. We investigated the phenotypic and functional characteristics of T cells with differential expression of PD-1 (high/low) and Tim-3 (positive/negative), using TIL directly isolated from head and neck squamous cell carcinomas (HNSCC). Unexpectedly, we found that expression of Tim-3 alone does not necessarily mark TIL as dysfunctional/exhausted. In Tim-3-TIL, PD-1 levels correlate with T cell dysfunction, with a PD-1low/intermed phenotype identifying recently activated and still functional cells, whereas PD-1hiTim-3- T cells are actually exhausted. Nonetheless, PD-1intermed cells are still potently suppressed by PD-L1. PD-1 expression was associated with reduced phosphorylation of ribosomal protein S6 (pS6), whereas Tim-3 expression was associated with increased pS6. Using a novel mouse model for inducible Tim-3 expression, we confirmed that expression of Tim-3 does not necessarily render T cells refractory to further activation. These results suggest the existence of PD-1 and Tim-3 crosstalk in regulating antitumor T cell responses, with important implications for anti-PD-1 immunotherapy.