Predicting response to immune checkpoint blockade in NSCLC with tumour-only RNA-seq.

BACKGROUND: Targeted RNA sequencing (RNA-seq) from FFPE specimens is used clinically in cancer for its ability to estimate gene expression and to detect fusions. Using a cohort of NSCLC patients, we sought to determine whether targeted RNA-seq could be used to measure tumour mutational burden (TMB) and the expression of immune-cell-restricted genes from FFPE specimens and whether these could predict response to immune checkpoint blockade. METHODS: Using The Cancer Genome Atlas LUAD dataset, we developed a method for determining TMB from tumour-only RNA-seq and showed a correlation with DNA sequencing derived TMB calculated from tumour/normal sample pairs (Spearman correlation = 0.79, 95% CI [0.73, 0.83]. We applied this method to targeted sequencing data from our patient cohort and validated these results against TMB estimates obtained using an orthogonal assay (Spearman correlation = 0.49, 95% CI [0.24, 0.68]). RESULTS: We observed that the RNA measure of TMB was significantly higher in responders to immune blockade treatment (P = 0.028) and that it was predictive of response (AUC = 0.640 with 95% CI [0.493, 0.786]). By contrast, the expression of immune-cell-restricted genes was uncorrelated with patient outcome. CONCLUSION: TMB calculated from targeted RNA sequencing has a similar diagnostic ability to TMB generated from targeted DNA sequencing.

The AP-1 transcription factor Batf controls T(H)17 differentiation.

Activator protein 1 (AP-1, also known as JUN) transcription factors are dimers of JUN, FOS, MAF and activating transcription factor (ATF) family proteins characterized by basic region and leucine zipper domains. Many AP-1 proteins contain defined transcriptional activation domains, but BATF and the closely related BATF3 (refs 2, 3) contain only a basic region and leucine zipper, and are considered to be inhibitors of AP-1 activity. Here we show that Batf is required for the differentiation of IL17-producing T helper (T(H)17) cells. T(H)17 cells comprise a CD4(+) T-cell subset that coordinates inflammatory responses in host defence but is pathogenic in autoimmunity. Batf(-/-) mice have normal T(H)1 and T(H)2 differentiation, but show a defect in T(H)17 differentiation, and are resistant to experimental autoimmune encephalomyelitis. Batf(-/-) T cells fail to induce known factors required for T(H)17 differentiation, such as RORgamma t (encoded by Rorc) and the cytokine IL21 (refs 14-17). Neither the addition of IL21 nor the overexpression of RORgamma t fully restores IL17 production in Batf(-/-) T cells. The Il17 promoter is BATF-responsive, and after T(H)17 differentiation, BATF binds conserved intergenic elements in the Il17a-Il17f locus and to the Il17, Il21 and Il22 (ref. 18) promoters. These results demonstrate that the AP-1 protein BATF has a critical role in T(H)17 differentiation.

Trends in primary care blood tests prior to lung and colorectal cancer diagnosis-A retrospective cohort study using linked Australian data.

INTRODUCTION: Abnormal results in common blood tests may occur several months before lung cancer (LC) and colorectal cancer (CRC) diagnosis. Identifying early blood markers of cancer and distinct blood test signatures could support earlier diagnosis in general practice. METHODS: Using linked Australian primary care and hospital cancer registry data, we conducted a cohort study of 855 LC and 399 CRC patients diagnosed between 2001 and 2021. Requests and results from general practice blood tests (six acute phase reactants [APR] and six red blood cell indices [RBCI]) were examined in the 2 years before cancer diagnosis. Poisson regression models were used to estimate monthly incidence rates and examine pre-diagnostic trends in blood test use and abnormal results prior to cancer diagnosis, comparing patterns in LC and CRC patients. RESULTS: General practice blood test requests increase from 7 months before CRC and 6 months before LC diagnosis. Abnormalities in many APR and RBCI tests increase several months before cancer diagnosis, often occur prior to or in the absence of anaemia (in 51% of CRC and 81% of LC patients with abnormalities), and are different in LC and CRC patients. CONCLUSIONS: This study demonstrates an increase in diagnostic activity in Australian general practice several months before LC and CRC diagnosis, indicating potential opportunities for earlier diagnosis. It identifies blood test abnormalities and distinct signatures that are early markers of LC and CRC. If combined with other pre-diagnostic information, these blood tests have potential to support GPs in prioritising patients for cancer investigation of different sites to expedite diagnosis.

The impact of pre-treatment smoking status on survival after chemoradiotherapy for locally advanced non-small-cell lung cancer.

INTRODUCTION: Smoking is a risk factor for the development of lung cancer and reduces life expectancy within the general population. Retrospective studies suggest that non-smokers have better outcomes after treatment for lung cancer. We used a prospective database to investigate relationships between pre-treatment smoking status and survival for a cohort of patients with stage III non-small-cell lung cancer (NSCLC) treated with curative-intent concurrent chemoradiotherapy (CRT). METHODS: All patients treated with CRT for stage III NSCLC at a major metropolitan cancer centre were prospectively registered to a database. A detailed smoking history was routinely obtained at baseline. Kaplan-Meier statistics were used to assess overall survival and progression-free survival in never versus former versus current smokers. RESULTS: Median overall survival for 265 eligible patients was 2.21 years (95 % Confidence Interval 1.78, 2.84). It was 5.5 years (95 % CI 2.1, not reached) for 25 never-smokers versus 1.9 years (95 % CI 1.5, 2.7) for 182 former smokers and 2.2 years (95 % CI 1.3, 2.7) for 58 current smokers. Hazard ratio for death was 2.43 (95 % CI 1.32-4.50) for former smokers and 2.75 (95 % CI 1.40, 5.40) for current smokers, p = 0.006. Actionable tumour mutations (EGFR, ALK, ROS1) were present in more never smokers (14/25) than former (9/182) or current (3/58) smokers. TKI use was also higher in never smokers but this was not significantly associated with superior survival (Hazard ratio 0.71, 95 % CI 0.41, 1.26). CONCLUSIONS: Never smokers have substantially better overall survival than former or current smokers after undergoing CRT for NSCLC.

Integrative systems biology reveals NKG2A-biased immune responses correlate with protection in infectious disease, autoimmune disease, and cancer.

Infection, autoimmunity, and cancer are principal human health challenges of the 21st century. Often regarded as distinct ends of the immunological spectrum, recent studies hint at potential overlap between these diseases. For example, inflammation can be pathogenic in infection and autoimmunity. T resident memory (TRM) cells can be beneficial in infection and cancer. However, these findings are limited by size and scope; exact immunological factors shared across diseases remain elusive. Here, we integrate large-scale deeply clinically and biologically phenotyped human cohorts of 526 patients with infection, 162 with lupus, and 11,180 with cancer. We identify an NKG2A+ immune bias as associative with protection against disease severity, mortality, and autoimmune/post-acute chronic disease. We reveal that NKG2A+ CD8+ T cells correlate with reduced inflammation and increased humoral immunity and that they resemble TRM cells. Our results suggest NKG2A+ biases as a cross-disease factor of protection, supporting suggestions of immunological overlap between infection, autoimmunity, and cancer.

TSTEM-like CAR-T cells exhibit improved persistence and tumor control compared with conventional CAR-T cells in preclinical models.

Patients who receive chimeric antigen receptor (CAR)-T cells that are enriched in memory T cells exhibit better disease control as a result of increased expansion and persistence of the CAR-T cells. Human memory T cells include stem-like CD8+ memory T cell progenitors that can become either functional stem-like T (TSTEM) cells or dysfunctional T progenitor exhausted (TPEX) cells. To that end, we demonstrated that TSTEM cells were less abundant in infused CAR-T cell products in a phase 1 clinical trial testing Lewis Y-CAR-T cells (NCT03851146), and the infused CAR-T cells displayed poor persistence in patients. To address this issue, we developed a production protocol to generate TSTEM-like CAR-T cells enriched for expression of genes in cell replication pathways. Compared with conventional CAR-T cells, TSTEM-like CAR-T cells had enhanced proliferative capacity and increased cytokine secretion after CAR stimulation, including after chronic CAR stimulation in vitro. These responses were dependent on the presence of CD4+ T cells during TSTEM-like CAR-T cell production. Adoptive transfer of TSTEM-like CAR-T cells induced better control of established tumors and resistance to tumor rechallenge in preclinical models. These more favorable outcomes were associated with increased persistence of TSTEM-like CAR-T cells and an increased memory T cell pool. Last, TSTEM-like CAR-T cells and anti-programmed cell death protein 1 (PD-1) treatment eradicated established tumors, and this was associated with increased tumor-infiltrating CD8+CAR+ T cells producing interferon-γ. In conclusion, our CAR-T cell protocol generated TSTEM-like CAR-T cells with enhanced therapeutic efficacy, resulting in increased proliferative capacity and persistence in vivo.

A Multi-Center Real-World Experience of IMpower150 in Oncogene Driven Tumors and CNS Metastases.

BACKGROUND: There are limited real world data on the IMpower150 regimen in oncogene driven tumors and central nervous system metastases; this study aims to address this gap. MATERIALS AND METHODS: Retrospective analysis of patients with advanced non-small cell lung cancer treated with the IMpower150 regimen across 12 Australian sites between July 2018 and April 2021. Clinicopathologic and treatment parameters were correlated with efficacy and toxicity. RESULTS: A total of 106 patients identified with median follow up of 8 months (range 0-72). Median age was 61 years (range 33-83), 34% Asian and 58% never-smokers. An oncogene was reported in 94 (89%) patients, EGFR in 72 (68%). At treatment commencement, 50 (47%) patients had brain metastases, 21 (20%) leptomeningeal disease (LMD) and 47 (44%) liver metastases. 27% were treatment-naïve and pemetrexed was substituted for paclitaxel in 44 (42%). The overall response rate was 51% for all patients; 52% in patients with EGFR mutations. Patients with untreated brain metastases prior to commencing IMpower150 had a similar intracranial response as those with treated brain metastases (55% vs. 53%). The median time to treatment failure and overall survival from commencement of IMpower150 was 5.7 and 11.4 months respectively for the entire cohort and 5.2 and 10.5 months in those with an EGFR sensitizing mutation. Overall survival in patients with liver, brain metastases and LMD was 11.0, 11.4, and 7.1 months respectively. No new safety signals seen. CONCLUSION: In this largely oncogene positive, pre-treated population the IMpower150 regimen demonstrated clinically-meaningful responses, including in patients with CNS disease.

Neoadjuvant immunotherapy for non-small cell lung cancer: right drugs, right patient, right time?

Standard curative treatment of early-stage non-small cell lung cancer (NSCLC) involves surgery in combination with postoperative (adjuvant) platinum-based chemotherapy where indicated. Preoperative (neoadjuvant) therapies offer certain theoretical benefits compared with adjuvant approaches, including the ability to assess on-treatment response, reduce the tumor bulk prior to surgery, and enhance tolerability in the preoperative setting. Indeed, the use of neoadjuvant therapies are well established in other cancers such as breast and rectal cancers to debulk the tumor and guide ongoing therapy, and neoadjuvant chemotherapy has similar efficacy but less toxicity in NSCLC. More recently, immune checkpoint inhibitors (ICI) targeting programmed death-1 (PD1)/PD1-ligand 1 (PD-L1) have transformed the treatment of advanced NSCLC; the unique mechanisms of action of ICI offer additional rationale for assessment in the neoadjuvant setting. Preclinical studies in mouse cancer models support the proof of concept of neoadjuvant ICI (NAICI) through improvement of T-cell effector function and long-term memory induction. Preliminary early-phase human trial data support the proposition that NAICI in NSCLC may provide an feasible and potentially efficacious future treatment strategy and large, randomized phase III trials are currently recruiting to assess this approach. However, outstanding issues include defining optimal treatment combinations which balance high efficacy with acceptable toxicity, validating biomarkers to aid in patient selection, and avoiding potential pitfalls such as missing a window for successful surgery, that is, choosing the right drugs, for the right patient, at the right time. Predictive biomarkers to direct selection of therapy are required, and the validation of major pathological response (MPR) as a surrogate for survival will be important in the uptake of the neoadjuvant approach.

First-in-human phase I clinical trial of a combined immune modulatory approach using TetMYB vaccine and Anti-PD-1 antibody in patients with advanced solid cancer including colorectal or adenoid cystic carcinoma: The MYPHISMO study protocol (NCT03287427).

BACKGROUND: MYB is a transcription factor that is overexpressed in colorectal cancer (CRC) and also a driver mutation in adenoid cystic carcinoma (AdCC). Therefore, the MYB protein is an ideal target to vaccinate against to aid recruitment of tumour infiltrating lymphocytes (TILs) against these tumours. The Peter MacCallum Cancer Centre (Melbourne, Australia) has engineered a DNA vaccine, TetMYB, based on the pVAX1 plasmid vector carrying a fusion construct consisting of the universal tetanus toxin T-cell epitopes flanking an inactivated MYB gene. METHODS: This prospective first-in-human phase I single-arm multi-centre clinical trial involves patients with metastatic CRC or AdCC. Stage 1 will evaluate the safety profile of escalating doses of TetMYB vaccine, given sequentially and in combination with an anti-PD-1 inhibitory antibody, to determine the maximum tolerated dose (MTD). Stage 2 will assess the MTD in an expanded cohort. The calculated sample size is 32 patients: 12 in Stage 1 and 20 in Stage 2. The expected total duration of the trial is 3 years with 15 months of recruitment followed by a minimum of 18 months follow-up. DISCUSSION: MYB transcription factor is aberrantly overexpressed in a range of epithelial cancers, not limited to the above tumour types. Based on promising pre-clinical data of vaccine-induced tumour clearance and establishment of anti-tumour memory, we are embarking on this first-in-human trial. If successful, the results from this trial will allow progression to a Phase II trial and validation of this breakthrough immunotherapeutic approach, not only in CRC and AdCC, but other MYB over-expressing cancers. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03287427. Registered: September 19, 2017.

Feasibility of 5-fluorouracil pharmacokinetic monitoring using the My-5FU PCM™ system in a quaternary oncology centre.

PURPOSE: 5-Fluorouracil (5FU) drug exposure correlates with treatment response and toxicity in cancer patients. Dosing is based upon body surface area which does not correlate with 5FU pharmacokinetics (PK)/pharmacodynamics. Therapeutic drug monitoring has enabled real-time 5FU dose adjustments: reducing toxicity with increased efficacy. The aim of this study was to assess feasibility of a 5FU monitoring service utilising a commercial kit in a quaternary cancer centre and to compare PK parameters to previously published studies. METHODS: Cancer patients receiving continuous infusional (CI) 5FU with ECOG PS 0-2, and adequate organ function, were eligible. Patients had blood samples taken at t = 0, mid infusion (if feasible) then 2 h pre infusion end. 5FU levels were measured using a commercial kit (My-5FU PCM™). A feasibility questionnaire was completed by trial nurses and toxicity data were recorded at baseline and at the commencement of the next cycle. 5FU pharmacokinetic exposure parameters were calculated. RESULTS: Twenty patients (12 male; 8 female), median age 62, (range 37-71) had samples taken. Twenty (100%) feasibility forms were available for assessment. Blood samples were taken at 51/69 (74%) specified time points. Ease of sample processing was recorded as easy in all 20 patients. Patient compliance with scheduled visits was 18/20 (90%). One form noted other difficulties with predicting end of infusion time. 19/20 patients had blood samples analysed. Mean measured 5FU AUC (0-Tlast) for 5FU 1 g/m2 with platinum: 35.8 h mg/L (range 28.56-44.26), mean Css 372.2 µg/L (range 297.5-461.0); 5FU 600 mg/m2 with platinum: 12.42 h mg/L (range 6.91-18.29), mean Css 111.0 µg/L (72.0-190.5) and 5FU 2400 mg/m2 as part of FOLFOX ± bevacizumab: 14.75 h mg/L (range 6.74-22.93), mean Css 320.70 µg/L (range 146.5-498.5). One patient had grade 4 neutropenia and one patient without PK parameters experienced febrile neutropenia (grade 4 neutropenia). Mucositis was observed in two patients: [5FU/platinum (1), grade 1, FOXFOX ± bevacizumab (1) grade 1]. Diarrhoea was reported in three patients [5FU/platinum (2) grade 1-2, FOXFOX ± bevacizumab (1) grade 1]. CONCLUSION: Therapeutic 5FU drug monitoring was feasible using commercial kits and analysers and hence warrants development as a routine standard of care in cancer patients. The variability in the 5FU exposure parameters is consistent with other studies using the My 5FU PCM kit.

Unilateral radiotherapy treatment for p16/human papillomavirus-positive squamous cell carcinoma of unknown primary in the head and neck.

OBJECTIVES/HYPOTHESIS: The outcomes of unilateral radiotherapy treatment for patients with p16/HPV-positive squamous cell carcinomas of unknown primary (SCCUP) affecting cervical lymph nodes are under-reported. Compared to radiating large volumes of the pharyngeal axis (the more common approach), this is potentially a much less toxic treatment for a good prognosis group. STUDY DESIGN: Retrospective cohort study. METHODS: We identified patients with SCCUP who were treated radically at our center and did not have parotid or isolated level IV or V nodal involvement. Failure-free and overall survivals were calculated using Kaplan-Meier methods. RESULTS: From 2004 to 2012, there were 49 radically treated patients with SCCUP. Fourteen patients had bilateral neck treatment (they had bilateral nodal disease or suspected lesions in the base of tongue, though not proven with biopsy), two had surgery alone, whereas 33 had unilateral radiotherapy (after neck dissection, excisional biopsy, or definitively with concurrent chemotherapy). Of the 33 patients, 21 tested positive to p16/HPV and had median follow-up of 57 months. In this group, no isolated contralateral neck failures or putative primaries emerged. There was 1/21 (4.3%) ipsilateral neck failure, 1/21 (4.3%) concurrent contralateral neck and distant failure, and 1/21 (4.3%) patient with distant failure. The 5-year freedom from failure was 78% (95% confidence interval [CI]: 56%-100%) and overall survival was 90% (95% CI: 79%-100%). CONCLUSIONS: With no emergence of putative primaries and no isolated contralateral neck failures, this single-institution experience in p16/HPV-positive SCCUP patients suggests that unilateral radiotherapy may be an underutilized management strategy. LEVELS OF EVIDENCE: 4 Laryngoscope, 128:2076-2083, 2018.

Reduced abundance of the E3 ubiquitin ligase E6AP contributes to decreased expression of the INK4/ARF locus in non-small cell lung cancer.

The tumor suppressor p16INK4a, one protein encoded by the INK4/ARF locus, is frequently absent in multiple cancers, including non-small cell lung cancer (NSCLC). Whereas increased methylation of the encoding gene (CDKN2A) accounts for its loss in a third of patients, no molecular explanation exists for the remainder. We unraveled an alternative mechanism for the silencing of the INK4/ARF locus involving the E3 ubiquitin ligase and transcriptional cofactor E6AP (also known as UBE3A). We found that the expression of three tumor suppressor genes encoded in the INK4/ARF locus (p15INK4b, p16INK4a, and p19ARF) was decreased in E6AP-/- mouse embryo fibroblasts. E6AP induced the expression of the INK4/ARF locus at the transcriptional level by inhibiting CDC6 transcription, a gene encoding a key repressor of the locus. Luciferase assays revealed that E6AP inhibited CDC6 expression by reducing its E2F1-dependent transcription. Chromatin immunoprecipitation analysis indicated that E6AP reduced the amount of E2F1 at the CDC6 promoter. In a subset of NSCLC samples, an E6AP-low/CDC6-high/p16INK4a-low protein abundance profile correlated with low methylation of the gene encoding p16INK4a (CDKN2A) and poor patient prognosis. These findings define a previously unrecognized tumor-suppressive role for E6AP in NSCLC, reveal an alternative silencing mechanism of the INK4/ARF locus, and reveal E6AP as a potential prognostic marker in NSCLC.

Weekly cisplatin and radiotherapy for low risk, locoregionally advanced human papillomavirus-positive oropharyngeal squamous cell carcinoma.

BACKGROUND: There is interest in different treatment strategies, including deintensification in good prognosis human papillomavirus-positive (HPV(+)) oropharyngeal squamous cell carcinoma (SCC). We reviewed our experience with weekly cisplatin in low-risk, locoregionally advanced HPV(+) oropharyngeal SCC since late 2009. METHODS: Data from patients with low-risk HPV(+) oropharyngeal SCC treated with weekly cisplatin (40 mg/m(2) ) and 70 Gy radiotherapy were collected. Low risk was defined as stage III to IV oropharyngeal SCC excluding T1-2N1, T4 or N3 disease, or N2b to N2c disease in patients with >10 pack-year smoking history. RESULTS: Of 31 patients, the median age was 56 years (range, 41-69 years). All patients completed 70 Gy radiotherapy within 51 days and 84% completed at least 5 cycles of cisplatin. Grade 3 mucositis occurred in 22 patients (71%) and grade 3 febrile neutropenia in 6 patients (19%). No patients required enteral feeding at 12 months. The median follow-up was 30 months (range, 21-57 months) with no recurrences or deaths. CONCLUSION: Concurrent weekly cisplatin is relatively well-tolerated and associated with excellent disease control in low-risk, locoregionally advanced HPV(+) oropharyngeal SCC. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1117-E1121, 2016.

Effect of Platinum-Based Chemoradiotherapy on Cellular Proliferation in Bone Marrow and Spleen, Estimated by (18)F-FLT PET/CT in Patients with Locally Advanced Non-Small Cell Lung Cancer.

UNLABELLED: Historically, it has been difficult to monitor the acute impact of anticancer therapies on hematopoietic organs on a whole-body scale. Deeper understanding of the effect of treatments on bone marrow would be of great potential value in the rational design of intensive treatment regimens. 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) is a functional radiotracer used to study cellular proliferation. It is trapped in cells in proportion to thymidine-kinase 1 enzyme expression, which is upregulated during DNA synthesis. This study investigates the potential of (18)F-FLT to monitor acute effects of chemotherapy on cellular proliferation and its recovery in bone marrow, spleen, and liver during treatment with 2 different chemotherapy regimens. METHODS: Sixty patients with non-small cell lung cancer underwent concurrent radical chemoradiotherapy to 60 Gy in 6 wk with either cisplatin/etoposide (C/E, n = 28) weeks 1 and 5 or weekly carboplatin/paclitaxel (C/P, n = 32) regimens. (18)F-FLT and (18)F-FDG PET with CT were performed at baseline, week 2 (day 9 for (18)F-FLT and day 10 for (18)F-FDG PET), and week 4 (day 23 for (18)F-FLT and day 24 for (18)F-FDG PET). Visual and semiquantitative standardized uptake value (SUV) measurements were performed in bone marrow outside the radiotherapy field, liver, spleen, and small bowel. These were correlated to blood counts and smears in a subset of patients. RESULTS: The C/E group exhibited a drop in bone marrow (18)F-FLT uptake at week 2 (median SUVmax [maximum SUV] decrease to 31%, 8.7-6.0, P < 0.001), with recovery at week 4, reflecting the absence of chemotherapy between these times. By contrast, the weekly C/P group showed gradually declining bone marrow uptake (P > 0.05). Spleen uptake in both cohorts decreased at week 2, with intense rebound activity at week 4 (SUVmax week 4 at 58% above baseline: 2.4-3.8, for C/E, respectively, 30% for C/P: 2.7-3.5, P < 0.001). Liver uptake changed little. (18)F-FLT changes preceded neutrophil count reductions. (18)F-FDG uptake in marrow liver and spleen changed much less than (18)F-FLT. CONCLUSION: (18)F-FLT imaging may be used to quantify impairment and recovery of bone marrow by specific chemotherapy regimens and may also enable imaging of organ-specific processes such as spleen activation. (18)F-FLT is superior to (18)F-FDG for this purpose. This technology may support novel treatment planning and monitoring approaches in oncology patients.

Correlation of p16 status, hypoxic imaging using [18F]-misonidazole positron emission tomography and outcome in patients with loco-regionally advanced head and neck cancer.

INTRODUCTION: We investigated the relationship between hypoxia, human papillomavirus (HPV) status and outcome in head and neck squamous cell carcinoma. METHODS: Patients with stage III and IV head and neck squamous cell carcinoma treated on phase I and II chemoradiation trials with 70-Gy radiation combined with tirapazamine/cisplatin or cisplatin/fluorouracil (5FU), hypoxic imaging using [18F]-misonidazole positron emission tomography and known HPV status (by p16 immunohistochemistry) were included in this sub-study. Separate analyses were conducted to consider the impact of tirapazamine on HPV-negative tumours in the phase II trial. RESULTS: Both p16-positive oropharyngeal tumours and p16-negative head and neck squamous cell carcinoma tumours had a high prevalence of tumour hypoxia; 14/19 (74%) and 35/44 (80%), respectively. The distribution of hypoxia (primary, nodal) was similar. On phase II, trial patients with p16-negative hypoxic tumours had worse loco-regional control with cisplatin and 5FU compared with tirapazamine and cisplatin (P < 0.001) and worse failure-free survival (hazard ratio = 5.18; 95% confidence interval, 1.98-13.55; P = 0.001). Only 1 out of 14 p16-positive patients on the phase II trial experienced loco-regional failure. CONCLUSION: Hypoxia, as assessed by [18F]-misonidazole positron emission tomography, is frequently present in both p16-positive and negative head and neck cancer. Further research is required to determine whether hypoxic imaging can be used to predict benefit from hypoxia-targeting therapies in patients with p16-negative tumours.

Treatment response in the neck: p16+ versus p16- oropharyngeal cancer.

INTRODUCTION: To compare nodal response rates following chemoradiotherapy in patients with p16+ and p16- oropharyngeal squamous cell carcinoma (OPSCC). METHODS: Patients with node-positive OPSCC treated at Peter MacCallum Cancer Centre on the published phase I-III tirapazamine trials were identified. All patients had conventional assessment (clinical examination (CA), CT and/or MRI) and positron emission tomography (PET) at both baseline and 2-4 months post-treatment. RESULTS: There were 30 p16+ and 18 p16- patients, the former group having significantly higher stage nodal disease (P = 0.016). The mean overall reduction in nodal size at post-treatment assessment was similar in p16+ and p16- patients (78% vs. 75%), and no statistically significant difference in nodal complete response (CR) rates was detected by either CA (50% vs. 39%, P = 0.35) or PET/PET-CT (93% vs. 83%, P = 0.19). PET was significantly more accurate in determining the true nodal CR rate in both groups, with a negative predictive value of 96%. CONCLUSION: Nodal response rates following chemoradiotherapy appear to be similar in p16+ and p16- patients when assessed by either CA or PET/PET-CT. However, higher nodal CR was seen in PET/PET-CT compared with CA in both groups. Metabolic imaging is more accurate than CA in assessing nodal response post-treatment.

Prognostic significance of p16INK4A and human papillomavirus in patients with oropharyngeal cancer treated on TROG 02.02 phase III trial.

PURPOSE: To determine the prognostic importance of p16 and human papillomavirus (HPV) in patients with oropharyngeal cancer treated on a phase III concurrent chemoradiotherapy trial. PATIENTS AND METHODS: Patients with stage III or IV head and neck squamous cell cancer were randomly assigned to concurrent radiotherapy and cisplatin with or without tirapazamine. In this substudy, analyses were restricted to patients with oropharyngeal cancer. p16 was detected by immunohistochemistry, and HPV was detected by in situ hybridization and polymerase chain reaction. RESULTS: Slides were available for p16 assay in 206 of 465 patients, of which 185 were eligible, and p16 and HPV were evaluable in 172 patients. One hundred six (57%) of 185 were p16-positive, and in patients evaluable for both p16 and HPV, 88 (86%) of 102 p16-positive patients were also HPV-positive. Patients who were p16-positive had lower T and higher N categories and better Eastern Cooperative Oncology Group (ECOG) performance status. p16-positive tumors compared with p16-negative tumors were associated with better 2-year overall survival (91% v 74%; hazard ratio [HR], 0.36; 95% CI, 0.17 to 0.74; P = .004) and failure-free survival (87% v 72%; HR, 0.39; 95% CI, 0.20 to 0.74; P = .003). p16 was a significant prognostic factor on multivariable analysis (HR, 0.45; 95% CI, 0.21 to 0.96; P = .04). p16-positive patients had lower rates of locoregional failure and deaths due to other causes. There was a trend favoring the tirapazamine arm for improved locoregional control in p16-negative patients (HR, 0.33; 95% CI, 0.09 to 1.24; P = .13). CONCLUSION: HPV-associated oropharyngeal cancer is a distinct entity with a favorable prognosis compared with HPV-negative oropharyngeal cancer when treated with cisplatin-based chemoradiotherapy.

Frequent and focal FGFR1 amplification associates with therapeutically tractable FGFR1 dependency in squamous cell lung cancer.

Lung cancer remains one of the leading causes of cancer-related death in developed countries. Although lung adenocarcinomas with EGFR mutations or EML4-ALK fusions respond to treatment by epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) inhibition, respectively, squamous cell lung cancer currently lacks therapeutically exploitable genetic alterations. We conducted a systematic search in a set of 232 lung cancer specimens for genetic alterations that were therapeutically amenable and then performed high-resolution gene copy number analyses. We identified frequent and focal fibroblast growth factor receptor 1 (FGFR1) amplification in squamous cell lung cancer (n = 155), but not in other lung cancer subtypes, and, by fluorescence in situ hybridization, confirmed the presence of FGFR1 amplifications in an independent cohort of squamous cell lung cancer samples (22% of cases). Using cell-based screening with the FGFR inhibitor PD173074 in a large (n = 83) panel of lung cancer cell lines, we demonstrated that this compound inhibited growth and induced apoptosis specifically in those lung cancer cells carrying amplified FGFR1. We validated the FGFR1 dependence of FGFR1-amplified cell lines by FGFR1 knockdown and by ectopic expression of an FGFR1-resistant allele (FGFR1(V561M)), which rescued FGFR1-amplified cells from PD173074-mediated cytotoxicity. Finally, we showed that inhibition of FGFR1 with a small molecule led to significant tumor shrinkage in vivo. Thus, focal FGFR1 amplification is common in squamous cell lung cancer and associated with tumor growth and survival, suggesting that FGFR inhibitors may be a viable therapeutic option in this cohort of patients.