Prospective development study of the Versius Surgical System for use in transoral robotic surgery: an IDEAL stage 1/2a first in human and initial case series experience.

PURPOSE: Transoral robotic surgery is well established in the treatment paradigm of oropharyngeal pathology. The Versius Surgical System (CMR Surgical) is a robotic platform in clinical use in multiple specialities but is currently untested in the head and neck. This study utilises the IDEAL framework of surgical innovation to prospectively evaluate and report a first in human clinical experience and single centre case series of transoral robotic surgery (TORS) with Versius. METHODS: Following IDEAL framework stages 1 and 2a, the study evaluated Versius to perform first in human TORS before transitioning from benign to malignant cases. Iterative adjustments were made to system setup, instrumentation, and technique, recorded in accordance with IDEAL recommendations. Evaluation criteria included successful procedure completion, setup time, operative time, complications, and subjective impressions. Further evaluation of the system to perform four-arm surgery was conducted. RESULTS: 30 TORS procedures were successfully completed (15 benign, 15 malignant) without intraoperative complication or conversion to open surgery. Setup time significantly decreased over the study period. Instrumentation challenges were identified, urging the need for TORS-specific instruments. The study introduced four-arm surgery, showcasing Versius' unique capabilities, although limitations in distal access were observed. CONCLUSIONS: TORS is feasible with the Versius Surgical System. The development of TORS-specific instruments would benefit performance and wider adoption of the system. 4-arm surgery is possible however further evaluation is required. Multicentre evaluation (IDEAL stage 2b) is recommended.

Soft Tissue Robotic Assisted Orbital Surgery Using da Vinci SP: A Cadaveric Experience.

PURPOSE: Robotic surgical techniques have transformed many surgical specialties however robotic techniques and applications have been much more limited in ophthalmology. This study aims to evaluate the feasibility of robotic assisted orbital surgery using a single-port novel robotic platform, the da Vinci SP. METHODS: A series of orbital procedures were performed in cadaveric specimens utilizing the da Vinci SP robotic system. The procedures performed included lacrimal gland dissection and biopsy, medial and lateral orbital wall dissections, enucleation, and lid-sparing orbital exenteration. Successful completion of each procedure was defined by the operating surgeon and was considered the primary outcome and marker of feasibility. RESULTS: Seven cadaveric procedures were performed in 3 cadaveric specimens. All 7 procedures were completed successfully without complication. Setup optimization occurred throughout the study and setup and operative times were acceptable. Three instrument arms and 1 endoscope were utilized throughout the study allowing 3 arm operating and dynamic retraction. Instrument size was found to limit surgical access and precision particular at the orbital apex. CONCLUSIONS: This preclinical study demonstrates that the da Vinci SP can be utilized within the orbit and is feasible for several applications. Robotic surgical systems offer significant advantages over conventional techniques and should be embraced. However, current commercially available robotic platforms are not optimized for the orbit and have their limitations although they may be suitable for some clinical applications.

Setting up a nurse-led 2-week-wait head and neck cancer diagnostic service.

The number of urgent '2-week-wait' referrals to hospital for people with suspected head and neck cancer being sent by primary care is constantly growing and it is becoming increasingly difficult for head and neck cancer services to meet this demand. In order for trusts to meet their Faster Diagnosis Standards, there needs to be an effective and efficient way to ensure there is capacity for patients to receive the appropriate assessments and diagnostic investigations without compromising the quality of care delivered. This article presents the proposal of introducing a nurse-led 2-week-wait clinic to meet the ever-growing demands on the service. There is discussion of the consultant-led training programme used to upskill an advanced nurse practitioner in a single-centre study, as well as explanation of the processes followed to maintain patient safety throughout the pilot project. There will also be consideration of clinical governance and discussion of how patient satisfaction with the novel service will be measured.

Clinical outcomes in relapsed oropharyngeal cancer after definitive (chemo) radiotherapy.

OBJECTIVES: To report clinical outcomes of relapsed oropharyngeal squamous cell carcinoma (OPSCC) after definitive intensity-modulated (chemo)radiotherapy [(C)RT]. MATERIALS AND METHODS: Data for all relapsed patients treated for OPSCC with definitive (C)RT between 2010 and 2016 were collected. Primary end-point was post-failure survival (PFS). RESULTS: Overall, 273 OPSCC patients completed definitive (C)RT. Of these, 42 cases (n = 26 human papilloma virus (HPV)-negative; n = 16 HPV-positive) had relapsed (n = 23 persistent disease; n = 19 recurrent disease) and were included in the final analysis. Two-year PFS for the entire population was 30.6%; 20.5% for HPV-negative and 43.8% for HPV-positive patients. Salvage curative surgery was associated with a significantly higher 2 years PFS rate (56.2%) compared with palliative treatment (22.9%) and best supportive care (0%) (p < 0.001). A positive trend in 2 years PFS was recorded in the early complete response cases (49.5%) versus patients who did not achieve a complete response within 3 months of the end of (C)RT (23.0%) (p = 0.11). CONCLUSION: A higher PFS rate is achieved when relapsed OPSCC cases are treated with salvage curative intent. HPV-positive disease and early complete response within 3 months from the end of (C)RT may be related to better PFS.

Water soluble swallow for leak detection after total laryngectomy post radiotherapy.

AIM: Pharyngeal leak (PL) and pharyngocutaneous fistula (PCF) are serious complications following total laryngectomy and their incidence is higher in the salvage setting. The aim of this study is to describe the accuracy of water soluble swallow (WSS) to rule out salivary postoperative leak after salvage total laryngectomy (STL) to expedite start of oral intake. MATERIAL AND METHODS: Retrospective study including patients undergoing STL between 2008 and 2021 at Guy's Hospital. WSS was routinely performed within 15 days post operation. RESULTS: Sixty-six patients underwent STL. Nine developed clinically diagnosed PCF; one died before having WSS. Fifty-six patients underwent WSS post STL. WSS was performed within 15 days after STL when no postoperative complications occurred (76.8%). Among patients undergoing WSS with no clinical suspicion for fistula (56), PL was identified in 15 cases (26.8%). They were managed conservatively; PCF was avoided in 7(46.7%) cases. Three patients (7.3%) developed PCF after having started oral intake with a negative WSS. These three cases were further analysed, 2 cases where recorded at the beginning of the studied period when less experience was available possibly leading to incorrect results. Sensitivity and negative predictive value (NPV) for fistula prediction were 72.7% and 92.7%, respectively. CONCLUSION: Taking into account the high NPV of WSS, it is safe to start oral intake after negative WSS. Further studies to evaluate its accuracy earlier on after SLT are justified taking into account the results and the impact that delayed feeding has on patient's quality of life.

Locally Advanced Scalp Tumors: Clinical and Survival Outcomes of a Tertiary Unit.

INTRODUCTION: Locally advanced nonmelanoma skin cancers of the head and neck are well described in the current literature. However, data about clinical and survival outcomes are lacking. We present survival data from a tertiary head and neck cancer unit in London. METHODS: A retrospective analysis of data collected from a single institution was conducted. All patients with locally advanced cutaneous scalp carcinomas invading the skull between 2011 and 2019 were included. Data included patient demographics, tumor, comorbidities, interventions, flap survival, and metal work exposure. Survival outcomes were examined using Kaplan-Meier analysis. RESULTS: Twenty-three patients were identified. The mean age was 72 years. Eighteen patients were male, and 5 were female. Five patients were immunosuppressed. Nineteen patients underwent outer cortex drill-down/full-thickness calvarial resection, followed by reconstruction with free tissue transfer. Six patients had titanium mesh reconstruction after segmental skull resections. Three patients underwent further surgery because of exposed metalwork. Disease-free survival at 3 years after surgery was 60%. CONCLUSIONS: Locally advanced nonmelanoma skin cancers invading the bone are sporadic. There are little published data on clinical and survival outcomes in this group. Despite the nature of these skin lesions, a high degree of local control can be obtained by extensive surgical resection, outer table drill-down, and calvarial resection. We conclude that aggressive management of the bony invasion improves disease-free survival and improves local control.

Outcomes of salvage surgery for the oropharynx and larynx: a contemporary experience in a UK Cancer Centre.

INTRODUCTION: The purpose of this study was to review our recent experience of salvage surgery, comparing larynx and oropharynx recurrence patterns. METHODS: A single centre, retrospective review of salvage surgery for recurrent head and neck cancer including patients between 2008 and 2016. RESULTS: 61 patients were identified, 36 underwent salvage laryngectomy and 25 received oropharyngeal resections. The median overall survival of oropharyngeal recurrent tumors was 26 months (95% CI 15-118 months) and for laryngeal tumors was 23 months (95% CI 11-38 months), p = 0.1008. There was a significant overall survival benefit in patients with negative resection margin. The median survival in the negative margin group was 38 months (95% CI 25-108 months) compared to the positive margin group, 9 months (95% CI 5-15 months), p < 0.0001. CONCLUSION: Survival results following surgical salvage in the larynx and oropharynx appear to be similarly poor. Those patients with clear margins appear to have a significantly better prognosis.

Next-Generation Robotic Head and Neck Surgery.

Following the inception of transoral robotic surgery (TORS) in 2005, the field of robotic head and neck surgery has undergone refinement and innovation. Optimizing patient outcome, preserving function, and limiting morbidity are the key drivers. The next leap forward is another generation of flexible robotic surgical systems. Several such systems are under clinical and preclinical evaluation. A new single-port (Sp) robotic surgical architecture is now available integrating three fully articulating instruments and a flexible three-dimensional high-definition camera delivered through a 25-mm cannula. Preclinical feasibility studies of the Sp in human cadaver and porcine models suggest improved application compared to existing platforms for oropharyngeal and nasopharyngeal resection. With 3-handed manipulation of tissue, traction and countertraction may be used to deliver a more precise surgical dissection of head and neck anatomy than is currently possible. The single-port design permits greater access and maneuverability for the bedside surgical assistant. An alternative currently available in clinical use includes the Flex® system using a robotic camera and manually controlled endoscopic instruments. The Cambridge Medical Robotics Versius system is undergoing preclinical evaluation for TORS and may offer a novel modular approach. All of these systems allow the head and neck surgeon to reach further beyond the upper aerodigestive tract with greater agility and precision, expanding the boundaries of minimal access head and neck surgery.

(18)F-FDG PET/CT to assess response and guide risk-stratified follow-up after chemoradiotherapy for oropharyngeal squamous cell carcinoma.

PURPOSE: To evaluate the use of (18)F-FDG PET/CT as the principal investigation to assess tumour response, to determine the need for further surgery and to guide follow-up following radical chemoradiotherapy for stage III/IV oropharyngeal squamous cell carcinoma (OPSCC). METHODS: A retrospective analysis was undertaken in 146 patients treated at our centre with radical chemoradiotherapy for OPSCC and who had a PET/CT scan to assess response. According to the PET/CT findings, patients were divided into four groups and recommendations: (1) complete metabolic response (enter clinical follow-up); (2) low-level uptake only (follow-up PET/CT scan in 12 weeks); (3) residual uptake suspicious for residual disease (further investigation with or without neck dissection); and (4) new diagnosis of distant metastatic disease (palliative treatment options). RESULTS: The initial PET/CT scan was performed at a median of 12.4 weeks (range 4.3 - 21.7 weeks) following treatment. Overall sensitivity and specificity rates were 92.0 % (74.0 - 99.0 %) and 85 % (77.5 - 90.9 %). Of the 146 patients, 90 (62 %) had a complete response and had estimated 3-year overall and disease-free survival rates of 91.9 % (85.6 - 98.2 %) and 85.6 % (78.0 - 93.2 %), respectively, 17 (12 %) had residual low-level uptake only (with two having confirmed residual disease on subsequent PET/CT, both surgically salvaged), 30 (21 %) had suspicious residual uptake (12 proceeded to neck dissection; true positive rate at surgery 33 %). HPV-positive patients with reassuring PET/CT findings had an estimated 3-year progression-free survival rate of 91.7 % (85.2 - 98.2 %), compared with 66.2 % (41.5 - 90.9 %) of HPV-negative patients. CONCLUSION: A strategy of using PET/CT results alongside clinical examination to help select patients for salvage surgery appears successful. Despite a complete response on the 12-week PET/CT scan, HPV-negative patients have a significant risk of disease relapse in the following 2 years and further studies to assess whether surveillance imaging in this group could improve outcomes are warranted.

Quantification of lymph nodes in the central compartment of the neck: a cadaveric study.

Differentiated thyroid cancer (DTC) accounts for over 90 % of thyroid malignancies, and is frequently associated with central neck compartment nodal metastasis that requires a therapeutic central compartment neck dissection (CCND) for clinically evident nodes. Current knowledge on the expected lymph node yield from a CCND is limited, compared with data on the lateral neck. The aim of our study was to accurately quantify nodal yield from the cadaveric central neck compartment. Twenty-eight cadaveric necks were dissected and the central neck compartment was subdivided into four regions: pre-laryngeal (delphian), pre-tracheal, right and left para-tracheal regions. Each cadaver had a thyroid gland, which was also removed, and the CCND tissue in each compartment was processed and examined by a consultant histopathologist. Only lymphoid tissue with a defined microscopic fibrous capsule and subcapsular sinus was included in the node count. The median total lymph node count per cadaver was four (range 1-16), with a median of one node detectable in each para-tracheal region (range 0-7) and the pre-tracheal region (range 0-8). The median pre-laryngeal node count was 0 (range 0- 2). The average lymph node size across all compartments was 2.9 mm. This is the first European study to assess cadaveric central neck lymph nodes and establish baseline counts for nodal yield. If a prophylactic or therapeutic CCND is required during thyroid surgery, those involved in DTC management must recognise that there is a wide range, and low median yield of central neck compartment lymph nodes.

Preclinical in vivo modeling of cytokine release syndrome induced by ErbB-retargeted human T cells: identifying a window of therapeutic opportunity?

The ErbB network is dysregulated in many solid tumors. To exploit this, we have developed a chimeric Ag receptor (CAR) named T1E28z that targets several pathogenetically relevant ErbB dimers. T1E28z is coexpressed with a chimeric cytokine receptor named 4αß (combination termed T4), enabling the selective expansion of engineered T cells using IL-4. Human T4(+) T cells exhibit antitumor activity against several ErbB(+) cancer types. However, ErbB receptors are also expressed in several healthy tissues, raising concerns about toxic potential. In this study, we have evaluated safety of T4 immunotherapy in vivo using a SCID beige mouse model. We show that the human T1E28z CAR efficiently recognizes mouse ErbB(+) cells, rendering this species suitable to evaluate preclinical toxicity. Administration of T4(+) T cells using the i.v. or intratumoral routes achieves partial tumor regression without clinical or histopathologic toxicity. In contrast, when delivered i.p., tumor reduction is accompanied by dose-dependent side effects. Toxicity mediated by T4(+) T cells results from target recognition in both tumor and healthy tissues, leading to release of both human (IL-2/IFN-γ) and murine (IL-6) cytokines. In extreme cases, outcome is lethal. Both toxicity and IL-6 release can be ameliorated by prior macrophage depletion, consistent with clinical data that implicate IL-6 in this pathogenic event. These data demonstrate that CAR-induced cytokine release syndrome can be modeled in mice that express target Ag in an appropriate distribution. Furthermore, our findings argue that ErbB-retargeted T cells can achieve therapeutic benefit in the absence of unacceptable toxicity, providing that route of administration and dose are carefully optimized.

Selective neck dissection as a therapeutic option in management of squamous cell carcinoma of unknown primary.

Carcinoma of unknown primary of the neck (CUP) is a metastasis presenting in one or more cervical lymph nodes, with no primary mucosal site identified. Retrospective case notes review of 25 consecutive patients (median age 55, 72% males) diagnosed as CUP who underwent neck dissection in a UK tertiary referral comprehensive cancer centre between 2000 and 2011. Median follow-up was 33 months. Nineteen patients underwent comprehensive neck dissections (six extended), six patients had selective neck dissection. Five year disease specific survival and regional recurrence free survival were 76 and 80% respectively. The overall rate of occult disease (disease not identified on preoperative evaluation, but found on histopathologic examination) was 8%, with rates of 0% in level I and 6% in level V. Our study suggests that in patients without preoperative evidence of disease in levels I or V selective neck dissection might be considered as an option, to facilitate preservation of the submandibular gland and accessory nerve without compromising oncological outcome. Larger studies should be performed before a change in practice can be advised.

Factors predictive of outcome following primary total laryngectomy for advanced squamous cell carcinoma.

The increasing use of primary chemoradiation (CRT) for laryngeal squamous cell carcinoma (SCC) means that historical surgical data sets are not representative of the modern laryngectomy patient. We analyse a contemporary total laryngectomy (TL) cohort to identify factors predictive of outcome. This is a retrospective consecutive case note review in a UK tertiary referral centre. Demographic, staging, treatment and outcome data were collected. Oncological outcomes are expressed using the Kaplan-Meier method. The log-rank test was used for univariate analysis and cox regression for multivariate analysis. Sixty consecutive patients between 2003 and 2010 underwent primary TL, 28 including partial pharyngectomy. Median age was 61 years and mean follow-up was 24 months (1-78 months). Thirty six patients died during the study period, 24 of their disease. Of the disease-specific deaths, two occurred peri-operatively, four from local, two from regional and 18 from distant disease [two patients had simultaneous local and distant recurrence (DR)]. Five-year overall survival, disease-specific survival, loco-regional recurrence-free survival and distant recurrence-free survival (DRFS) were 36, 51, 87, 62 %, respectively. Of 17 parameters analysed, pN-stage, extra-capsular spread, a non-cohesive tumour front, thyroid infiltration and involvement of level 6 were significant predictors of disease-specific survival (DSS) on univariate analysis. pN > 1 and the presence of adverse histological features were found to be independent predictors of DSS and DRFS on multivariate analysis. Neither was significantly associated with loco-regional recurrence-free survival. Around half of patients who undergo TL for stage IV SCC will die of disease within 5 years, with most deaths attributable to DR. Surgery provides excellent loco-regional control but patients, especially those with advanced nodal disease and/or adverse histological features, should be thoroughly screened for occult distant disease. Level of evidence 4.

Robotic assisted orbital surgery for resection of advanced periocular tumours - a case series report on the feasibility, safety and outcome.

PURPOSE: Orbital surgery benefits from well-designed instrumentation that offers gentle tissue manipulation, high manoeuvrability and control. Nevertheless, in confined spaces, tissue manipulation must be accomplished with exceptionally high accuracy and precision. This is where robotic surgery offers an advantage. We aimed to evaluate a robotic-assisted surgical system's feasibility, safety and outcome in assisting tumour clearance. PATIENTS AND METHODS: A case series of patients with advanced periocular tumours undergoing robotic-assisted globe-sparing resection was performed using the DaVinci XI system (Intuitive Surgical, Inc). Institutional ethics and multidisciplinary approval were sought in all cases. RESULTS: Four patients with advanced periocular tumours underwent robotic-assisted orbital surgery at a mean age of 63 years (range 42-86). Two patients were diagnosed with squamous cell carcinoma, and two had basal cell carcinoma. One patient was found to have positive lymph nodes at the time of surgery and underwent simultaneous parotidectomy and lymph node clearance. Clear resection of the primary tumour was achieved in all patients; three patients underwent further resection due to narrow margins prior to reconstruction. Patients were follow-up for at least one year, and three remained disease-free. One patient with pre-existing extra-orbital disease developed metastatic disease four months post-op. All patients preserved vision peri-operatively, with no complaints of diplopia. Moderate ocular surface disease was noted in two patients. CONCLUSION: Our series highlights the potential advantage of three-dimensional optics, multi-directional instrumentation and motion scaling technology to achieve globe-sparing tumour resection in advanced periocular tumours. However, further robotic instrumentation development is required for orbital surgery.

New robotic platform for transoral robotic surgery: an IDEAL stage 0 study.

Objectives: This study aims to assess the feasibility to perform transoral robotic surgery (TORS) with a new robotic platform, the Versius Surgical System (CMR Surgical, UK) in a preclinical cadaveric setting in accordance to stage 0 of the IDEAL-D framework. Design: IDEAL stage 0 preclinical assessment of the Versius Robotic System in TORS in human cadavers. Setting: All procedures were performed in a simulated operating theatre environment at a UK surgical training centre. Participants: 11 consultant head and neck surgeons from the UK, mainland Europe and the USA took part in TORS procedures on six human cadavers. Interventions: 3 key index procedures were assessed that represent the core surgical workload of TORS: lateral oropharyngectomy, tongue base resection and partial supraglottic laryngectomy. Main outcome measures: The primary outcome was the successful completion of each surgical procedure. Secondary outcomes included the optimisation of system setup, instrumentation and surgeon-reported outcomes for feasibility of each component procedural step. Results: 33 cadaveric procedures were performed and 32 were successfully completed. One supraglottic laryngectomy was not fully completed due to issues dividing the epiglottic cartilage with available instrumentation. Surgeon-reported outcomes met the minimal level of feasibility in all procedures and a consensus that it is feasible to perform TORS with Versius was reached. Available instrumentation was not representative of other robotic platforms used in TORS and further instrument optimisation is recommended before wider dissemination. Conclusions: It is feasible to perform TORS with the Versius Surgical System (CMR Surgical) within a pre-clinical cadaveric setting. Clinical evaluation is needed and appropriate with the system. Further instrument development and optimisation is desirable.

Correlation of the treatment sensitivity of patient-derived organoids with treatment outcomes in patients with head and neck cancer (SOTO): protocol for a prospective observational study.

INTRODUCTION: Organoids have been successfully used in several areas of cancer research and large living biobanks of patient-derived organoids (PDOs) have been developed from various malignancies. The characteristics of the original tumour tissue such as mutation signatures, phenotype and genetic diversity are well preserved in organoids, thus showing promising results for the use of this model in translational research. In this study, we aim to assess whether we can generate PDOs from head and neck squamous cell carcinoma (HNSCC) samples and whether PDOs can be used to predict treatment sensitivity in HNSCC patients as well as to explore potential biomarkers. METHODS AND ANALYSIS: This is a prospective observational study at a single centre (Guy's and St Thomas' NHS Foundation Trust) to generate PDOs from patients' samples to assess treatment response and to correlate with patients' treatment outcomes. Patients will be included if they are diagnosed with HNSCC undergoing curative treatment (primary surgery or radiotherapy) or presenting with recurrent or metastatic cancers and they will be categorised into three groups (cohort 1: primary surgery, cohort 2: primary radiotherapy and cohort 3: recurrent/metastatic disease). Research tumour samples will be collected and processed into PDOs and chemosensitivity/radiosensitivity will be assessed using established methods. Moreover, blood and other biological samples (eg, saliva) will be collected at different time intervals during treatment and will be processed in the laboratory for plasma and peripheral blood mononuclear cell (PBMC) isolation. Plasma and saliva will be used for circulating tumour DNA analysis and PBMC will be stored for assessment of the peripheral immune characteristics of the patients as well as to perform co-culture experiments with PDOs. SOTO study (correlation of the treatment Sensitivity of patient-derived Organoids with Treatment Outcomes in patients with head and neck cancer) uses the collaboration of several specialties in head and neck cancer and has the potential to explore multiple areas of research with the aim of offering a valid and effective approach to personalised medicine for cancer patients. ETHICS AND DISSEMINATION: This study was approved by North West-Greater Manchester South Research Ethics Committee (REC Ref: 22/NW/0023) on 21 March 2022. An informed consent will be obtained from all participants prior to inclusion in the study. Results will be disseminated via peer-reviewed publications and presentations at international conferences. TRIAL REGISTRATION NUMBER: NCT05400239.

Pre-operative tracheostomy does not impact on stomal recurrence and overall survival in patients undergoing primary laryngectomy.

Pre-operative tracheostomy (POT) to secure a critical airway up to several weeks before definitive laryngectomy in patients with laryngeal cancer has been proposed as a risk factor for poor oncologic outcome. Few modern papers, however, examine this question. The aim of this study is therefore to determine whether POT affects oncologic outcome with an emphasis on stomal/peristomal recurrence. This is a retrospective case note review of 60 consecutive patients undergoing curative primary total laryngectomy (TL) for advanced laryngeal squamous cell carcinoma (SCC). Demographic, staging, treatment and outcome data were collected. 27/60 (45 %) patients had POT and 33/60 did not. No patient underwent laser debulking. Median age was 62 years (39-90 years) and median follow-up of survivors was 31 months. 5-year overall survival (OS), disease-specific survival (DSS) and local recurrence-free survival (LRFS) of patients undergoing POT versus no POT was 28 versus 39 % (p = 0.947), 55 versus 46 % (p = 0.201) and 96 versus 88 % (p = 0.324) respectively. No statistically significant difference in OS, DSS and LRFS was found between patients undergoing POT and those not. Despite the relatively small case series, this evidence should reassure surgeons without the ability to perform trans-oral debulking that they should not hesitate to perform tracheostomy on a patient with airway obstruction due to laryngeal cancer. Appropriate definitive treatment meant that POT was not a risk factor for poor oncological outcome in our series.

Mechanistic insights into the interactions between cancer drivers and the tumour immune microenvironment.

BACKGROUND: The crosstalk between cancer and the tumour immune microenvironment (TIME) has attracted significant interest in the latest years because of its impact on cancer evolution and response to treatment. Despite this, cancer-specific tumour-TIME interactions and their mechanistic insights are still poorly understood. METHODS: Here, we compute the significant interactions occurring between cancer-specific genetic drivers and five anti- and pro-tumour TIME features in 32 cancer types using Lasso regularised ordinal regression. Focusing on head and neck squamous cancer (HNSC), we rebuild the functional networks linking specific TIME driver alterations to the TIME state they associate with. RESULTS: The 477 TIME drivers that we identify are multifunctional genes whose alterations are selected early in cancer evolution and recur across and within cancer types. Tumour suppressors and oncogenes have an opposite effect on the TIME and the overall anti-tumour TIME driver burden is predictive of response to immunotherapy. TIME driver alterations predict the immune profiles of HNSC molecular subtypes, and perturbations in keratinization, apoptosis and interferon signalling underpin specific driver-TIME interactions. CONCLUSIONS: Overall, our study delivers a comprehensive resource of TIME drivers, gives mechanistic insights into their immune-regulatory role, and provides an additional framework for patient prioritisation to immunotherapy. The full list of TIME drivers and associated properties are available at http://www.network-cancer-genes.org .