The role of transoral robotic surgery in the management of oropharyngeal cancer: a review of the literature

Outcomes for potentially Resectable patients undergoing primary chemoradiation treatment for T1-T2 HPV Negative oropharyngeal squamous cell carcinoma

BACKGROUND

Transoral surgical resectability (TOS) is a prognostic factor for patients with HPV+ T1-2 oropharyngeal squamous cell carcinoma (OPSCC) disease undergoing radiotherapy (RT), but it is unclear whether this holds for HPV-negative (HPV-) patients. We aimed to compare outcomes of potential TOS-candidates vs. non-TOS candidates, among patients who underwent RT/CRT for early T-stage HPV- OPSCC.

METHODS

For patients treated with RT/CRT for early T-stage HPV-negative OPSCC between 2014 and 2021, pretreatment imaging was reviewed by four head-and-neck surgeons, masked to clinical outcomes, to assess primary-site suitability for TOS. Extracapsular extension (ECE) was assessed by a head-and-neck neuroradiologist. We compared outcomes based on surgical resectability relating to: (1) the primary site tumor alone, and (2) the primary site plus the absence/presence of ECE (overall assessment). Kaplan-Meier curves for overall survival (OS), disease-specific survival (DSS), and progression-free survival (PFS) were compared using the log-rank test.

RESULTS

Seventy patients were included in the analysis. The primary site was TOS-favorable in 46/70 (66%). Based on the overall assessment, 41/70 (58.6%) were TOS-favorable. The 3-year OS, DSS and PFS for primary site TOS-favorable versus unfavorable were OS: 76.9% versus 37.4%; DSS: 78.1% versus 46.2%, PFS: 69.9% versus 41.3%, (log-rank test = 0.01, 0.03, 0.04; respectively). Additionally, patients with an overall assessment of TOS favorability demonstrated better survival outcomes compared with TOS-unfavorable patients (OS: 77.3% vs. 46.2%; DSS: 78.2% vs. 56.5%, PFS: 72.3% vs. 42.1%, log-rank test = 0.01, 0.04, 0.01; respectively).

CONCLUSION

Patients with TOS-favorable HPV-negative early T-stage OPSCC have superior survival outcomes than TOS-unfavorable patients.

Toward an Ecologically Valid Conceptual Framework for the Use of Artificial Intelligence in Clinical Settings: Need for Systems Thinking, Accountability, Decision-making, Trust, and Patient Safety Considerations in Safeguarding the Technology and Clinicians

The health care management and the medical practitioner literature lack a descriptive conceptual framework for understanding the dynamic and complex interactions between clinicians and artificial intelligence (AI) systems. As most of the existing literature has been investigating AI's performance and effectiveness from a statistical (analytical) standpoint, there is a lack of studies ensuring AI's ecological validity. In this study, we derived a framework that focuses explicitly on the interaction between AI and clinicians. The proposed framework builds upon well-established human factors models such as the technology acceptance model and expectancy theory. The framework can be used to perform quantitative and qualitative analyses (mixed methods) to capture how clinician-AI interactions may vary based on human factors such as expectancy, workload, trust, cognitive variables related to absorptive capacity and bounded rationality, and concerns for patient safety. If leveraged, the proposed framework can help to identify factors influencing clinicians' intention to use AI and, consequently, improve AI acceptance and address the lack of AI accountability while safeguarding the patients, clinicians, and AI technology. Overall, this paper discusses the concepts, propositions, and assumptions of the multidisciplinary decision-making literature, constituting a sociocognitive approach that extends the theories of distributed cognition and, thus, will account for the ecological validity of AI.

Assessment of Toxic Effects and Survival in Treatment Deescalation With Radiotherapy vs Transoral Surgery for HPV-Associated Oropharyngeal Squamous Cell Carcinoma: The ORATOR2 Phase 2 Randomized Clinical Trial

Importance

The optimal approach for treatment deescalation in human papillomavirus (HPV)-related oropharyngeal squamous cell carcinomas (OPSCCs) is unknown.

Objective

To assess a primary radiotherapy (RT) approach vs a primary transoral surgical (TOS) approach in treatment deescalation for HPV-related OPSCC.

Design, Setting, and Participants

This international, multicenter, open-label parallel-group phase 2 randomized clinical trial was conducted at 9 tertiary academic cancer centers in Canada and Australia and enrolled patients with T1-T2N0-2 p16-positive OPSCC between February 13, 2018, and November 17, 2020. Patients had up to 3 years of follow-up.

Interventions

Primary RT (consisting of 60 Gy of RT with concurrent weekly cisplatin in node-positive patients) vs TOS and neck dissection (ND) (with adjuvant reduced-dose RT depending on pathologic findings).

Main Outcomes and Measures

The primary end point was overall survival (OS) compared with a historical control. Secondary end points included progression-free survival (PFS), quality of life, and toxic effects.

Results

Overall, 61 patients were randomized (30 [49.2%] in the RT arm and 31 [50.8%] in the TOS and ND arm; median [IQR] age, 61.9 [57.2-67.9] years; 8 women [13.6%] and 51 men [86.4%]; 31 [50.8%] never smoked). The trial began in February 2018, and accrual was halted in November 2020 because of excessive toxic effects in the TOS and ND arm. Median follow-up was 17 months (IQR, 15-20 months). For the OS end point, there were 3 death events, all in the TOS and ND arm, including the 2 treatment-related deaths (0.7 and 4.3 months after randomization, respectively) and 1 of myocardial infarction at 8.5 months. There were 4 events for the PFS end point, also all in the TOS and ND arm, which included the 3 mortality events and 1 local recurrence. Thus, the OS and PFS data remained immature. Grade 2 to 5 toxic effects occurred in 20 patients (67%) in the RT arm and 22 (71%) in the TOS and ND arm. Mean (SD) MD Anderson Dysphagia Inventory scores at 1 year were similar between arms (85.7 [15.6] and 84.7 [14.5], respectively).

Conclusions and Relevance

In this randomized clinical trial, TOS was associated with an unacceptable risk of grade 5 toxic effects, but patients in both trial arms achieved good swallowing outcomes at 1 year. Long-term follow-up is required to assess OS and PFS outcomes.

Trial Registration

Clinicaltrials.gov Identifier: NCT03210103.

Flap Reconstruction of the Oropharyngeal Defect After Tumor Resection via Combined Transcervical and Transoral Approach in Patients With HPV-Positive and -Negative Oropharyngeal Squamous Cell Carcinoma

Objective

To investigate a novel surgical approach of combined transcervical parapharyngeal space (PPS) with the transoral approach to dissect oropharyngeal cancer.

Methods

31 patients who were pathologically diagnosed with oropharyngeal cancer and had undergone surgical treatment in Beijing Tongren Hospital during June 2018 and December 2020 were enrolled. All patients were squamous cell carcinoma patients. There were 25 males and 6 females, and the age ranged between 44 and 70 years old. The number of patients with T1, T2, T3, and T4 stage disease was 8, 15, 8, and 0, respectively, according to the American Joint Committee on Cancer staging method, 8th edition. After the dissection of the submandibular and cervical lymph nodes, the parapharyngeal space was exposed, and the parapharyngeal space lymph node and the outer borderline of the tumor were dissected, and then the inner borderline of the tumor was dissected via a transoral approach; the tumor was dissected en bloc, and the defects were reconstructed with the flap from the neck through the parapharyngeal space.

Results

Among the patients enrolled, 21 were HPV positive and 10 were HPV negative. 8 patients were free of lymph node metastasis. The tumor resection margins were negative in all 31 patients. Safe and sufficient excision of tumors was feasible by this new surgical approach, avoiding complications associated with mandibulotomy or lip-splitting. All patients had no obvious dysfunctions of swallowing and voice. By the time of this follow-up, none died caused by OPSCC, and only two patients suffered from local recurrence. The 3-year survival rate is 100%, and the 3-year recurrence-free survival rate is 84.58%.

Conclusion

The surgical approach of combined transcervical parapharyngeal space with the transoral approach was effective and safe. On this basis, this approach has the advantage of fewer postoperative complications and better functional results.

Current Status of Transoral Surgery for Patients With Early-Stage Pharyngeal and Laryngeal Cancers in Japan

As the laryngopharynx is closely related to swallowing, speech, and phonation, it is necessary to consider not only disease control but also a minimally invasive approach for the treatment of laryngopharyngeal cancer. Transoral surgery has been reported to be a minimally invasive method for treating these diseases. Transoral videolaryngoscopic surgery (TOVS) and endoscopic laryngo-pharyngeal surgery (ELPS) have been developed in Japan and recently emerged as treatments for patients with early stage pharyngeal and laryngeal cancers. However, securing an appropriate field of view and a narrow operating space during TOVS or ELPS are critical issues to be resolved for these surgeries. The clinical significance and safety of transoral robotic surgery (TORS) using the da Vinci Surgical System have been widely reported to provide surgeons with increased visualization and magnification, resulting in precise surgical margins and rapid functional recovery. In this context, a multi-institutional clinical study was conducted to evaluate the treatment outcomes of TORS for the treatment of laryngopharyngeal cancer in Japan, and the da Vinci Surgical System for oral robot-assisted surgery for these diseases was approved by the Pharmaceutical Affairs Agency in August 2018. This review provides an overview of the therapeutic effects of TOVS, ELPS, and TORS, with a particular focus on these therapeutic results in Japan.

Days alive and out of hospital following transoral robotic surgery: Cohort study of 262 patients with head and neck cancer

BACKGROUND

Days alive and out of hospital (DAOH) is a validated outcome in clinical trials, since it reflects procedure-associated morbidity and mortality. Transoral robotic surgery (TORS) has become a widely adopted procedure with increasing demand for knowledge and data on morbidity.

METHODS

Retrospective single-center assessment of a prospective TORS database comprising patients treated for malignancy between 2013 and 2018 using DAOH to describe procedure- and disease-related morbidity the first 12-postoperative months.

RESULTS

For 262 patients, median DAOH₃₆₅ was 357 days (IQR 351-360). Indications for TORS were (i) primary curative resection (61%), (ii) salvage resection (15%), and (iii) diagnostic work-up of cancer of unknown primary in the head and neck (24%). Median DAOH₃₆₅ was 359 days (IQR 351-361 days), 348 days (IQR 233-355), and 357 days (351-361), respectively. Pneumonia had the highest impact in DAOH₃₆₅ reduction.

CONCLUSION

Total median DAOH₃₆₅ after TORS was 357 days. The main cause leading to DAOH₃₆₅ reduction was pneumonia.

Nasogastric tube feeding after transoral robotic surgery for oropharynx carcinoma

PURPOSE

To determine the need for and predictors of nasogastric tube feeding (NGTF) use and duration after transoral robotic surgery (TORS) for oropharynx squamous cell carcinoma (OPSCC).

MATERIALS AND METHODS

This is a retrospective cohort study. For 95 OPSCC patients undergoing TORS with or without concurrent unilateral or bilateral neck dissections (ND), we evaluated NGTF use and duration, along with demographic, clinical, histopathologic, and treatment risk factors.

RESULTS

23.2% (22/95) of patients received NGTF. Univariate analysis found that NGTF was significantly more likely in larger tumor specimens (mean: 2.32 cm vs. 1.84 cm; p = 0.043) and after concurrent bilateral (46.7%) compared to unilateral (17.4%) ND (p = 0.043). Multivariable analysis also found increased tumor size (p = 0.035) and concurrent bilateral ND (p = 0.04) to be significant risk factors for NGTF. The following were not statistically significantly associated with NGTF use: sex, age, smoking history, HPV status, base of tongue (BOT) resection (20%) vs. radical tonsillectomy (25.9%), pT2 (27.0%) vs. pT1 (20.4%) vs pT0 (16.7%), BOT with (28.6%) vs. without epiglottis resection (22.2%), and surgery for additional margins the same day (27.3%) (all p > 0.1). Patients who underwent NGTF had a mean duration of 18 days (2-96, SD: 20.7 days) with 12 (55.6%) having over 2 weeks of use. No significant predictors of longer duration of NGTF were identified.

CONCLUSIONS

A majority of patients undergoing TORS do not need NGTF. When NGTF is needed, the duration of use is usually longer than 14 days. Larger tumor size and concurrent bilateral ND are risk factors for NGTF.

Transoral robotic surgery versus nonrobotic resection of oropharyngeal squamous cell carcinoma

The aim of this study is to evaluate the impact of transoral robotic surgery (TORS) compared to nonrobotic surgery (NRS) on overall survival in oropharyngeal squamous cell carcinoma (OPSCC). We performed a retrospective study of patients with HPV+ and HPV- OPSCC undergoing TORS or NRS with neck dissection using the National Cancer Database from the years 2010-2016. Among patients with OPSCC in our cohort, 3167 (58.1%) patients underwent NRS and 2288 (41.9%) underwent TORS. TORS patients demonstrated better overall survival than NRS patients (HPV+ patients: aHR 0.74, p = 0.02; HPV- patients: aHR 0.58, p < 0.01). Subsite analysis showed TORS was correlated with improved survival in base of tongue (BoT) primaries for both HPV+ (aHR 0.46, p = 0.01) and HPV- (aHR 0.42, p = 0.01) OPSCC. Compared to NRS, TORS is associated with improved overall survival for HPV+ and HPV- OPSCC, as well as greater overall survival for BoT primaries.

The implementation of TORS for head and neck surgery in Thailand

Transoral robotic surgery (TORS) is a novel surgical treatment of head and neck cancers, mainly for limited tumor in oropharynx and supraglottis. Despite the major advantage of favorable postoperative functional outcomes, many obstacles exist during the implementation of TORS, especially in a country where financial resources are modest. We demonstrated our experience of initiating this sophisticated technology at the largest tertiary hospital in Thailand. A retrospective review study was conducted in patients with benign or malignant lesions during 2014-2020 at Siriraj Hospital. Different periods of operation time between initial and subsequent cases were compared to evaluate learning-curve improvement. A total of 36 patients underwent TORS, with median follow-up time of 18 months. The average time of room set-up, anesthesia, and positioning was 37 ± 14, 13 ± 7, and 15 ± 7 min, respectively. Whilst, the average robotic procedure time and total time in room were 44 ± 19 and 118 ± 31 min, consecutively. There was no significant difference in any time interval, except the set-up time between initial and subsequent cases. The worthwhile utilization of TORS could be administered cost-effectively despite the complicated and daunting implementation of TORS. Whilst, meticulous planning and sufficient training prior to the initiation of TORS can favorably shorten the learning curve of operative staffs in the TORS team.

Preoperative predictors of dysphagia after transoral surgery

BACKGROUND

Transoral surgery (TOS) has been used to remove pharyngeal and laryngeal cancers with the objective of improving functional without worsening survival. However, there is a risk of postoperative dysphagia, which can severely impair quality of life. The aim of this study was to evaluate the preoperative predictive factors for postoperative dysphagia in patients undergoing TOS.

METHODS

One hundred and twenty patients who underwent TOS were evaluated in this study. The degree of dysphagia was evaluated using the Functional Outcome Swallowing Scale (FOSS) both preoperatively and 3 months postoperatively. Those whose FOSS stage was maintained postoperatively were classified into the FOSS-M group, while those with increased FOSS stage postopratively were classified into the FOSS-I group. The following parameters were assessed before surgery: age, weight, height, body mass index (BMI), forced expiratory volume in 1 s, and history of head and neck radiotherapy. Videofluoroscopy (VF) was performed preoperatively to evaluate swallowing function using the Penetration-Aspiration Scale (PAS).

RESULTS

The BMI of the FOSS-M group was significantly higher than that of the FOSS-I group. A history of radiotherapy was significantly more common in the FOSS-I group than in the FOSS-M group. Finally, preoperative PAS in the FOSS-M group was lower than that in the FOSS-I group.

CONCLUSION

This study suggested that patients with preoperative aspiration detected using VF might develop postoperative dysphagia severely. In addition, preoperative low BMI and a history of previous radiotherapy for head and neck cancer were associated with postoperative dysphagia. Objective examinations such as VF should be performed preoperatively.

De-intensification strategies in HPV-related oropharyngeal squamous cell carcinoma-a narrative review

Human papillomavirus-related (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) is a relatively new clinical entity that is dramatically on the rise globally. HPV+ OPSCC is thought to be a separate clinical entity compared to HPV− OPSCC with a distinct tumor biology. Patients with HPV associated disease have been shown to have a substantially better prognosis and overall survival than those patients with the HPV negative (HPV−) counterpart. The standard of care for OPSCC is definitive radiation therapy (RT) and concurrent chemoradiation therapy (CRT), for lower and higher stage disease, respectively. However, traditional CRT is also associated with severe acute and late toxicities affecting patient quality of life, such as severe mucositis, dry mouth and dysphagia. Considering that HPV+ OPSCC is on the rise in a younger, healthier patient population and the good prognosis of HPV-related disease, there has been a focus on reducing treatment toxicities and optimizing quality of life while maintaining favorable oncologic outcomes. A variety of such de-escalation regimens are currently being explored in recently completed and ongoing clinical trials. Alterations to the standard chemotherapy, radiation and surgical regimens are being explored. This review will provide an overview of the rationale for and available results of the major de-intensification strategies in the treatment of locally advanced HPV+ OPSCC.

Early fiberoptic endoscopic evaluation of swallow in transoral robotic surgery: Description of swallow function and recovery in the acute postoperative period for oropharyngeal squamous cell carcinoma

BACKGROUND

Transoral robotic surgery (TORS) is a minimally invasive approach for the treatment of oropharyngeal cancer. The effects on swallowing and speech need to be comprehensively evaluated to understand the associated morbidity.

METHODS

A prospective cohort of 21 patients was recruited to undergo pre-TORS and post-TORS swallowing and communication assessment. Fiberoptic endoscopic evaluation of swallowing (FEES) was used in the first postoperative week.

RESULTS

Sixteen participants (76.2%) had penetration-aspiration scores ≥3 or higher, seven (33.3%) aspirated on thin liquids, three (14.3%) did so silently. Prolonged recovery trajectory occurred for the majority of the cohort, particularly if TORS was followed by adjuvant radiotherapy. Swallowing and communication scores were significantly worse in base of tongue primary tumors and with advanced age.

CONCLUSION

Early FEES demonstrates a significant decline in swallowing function, including increased secretion load, pharyngeal residue, laryngeal penetration, and aspiration. Silent aspiration occurred in 14% and thus highlights the necessity for instrumental assessment to ascertain aspiration risk.

Role of Artificial Intelligence in Patient Safety Outcomes: Systematic Literature Review

BACKGROUND

Artificial intelligence (AI) provides opportunities to identify the health risks of patients and thus influence patient safety outcomes.

OBJECTIVE

The purpose of this systematic literature review was to identify and analyze quantitative studies utilizing or integrating AI to address and report clinical-level patient safety outcomes.

METHODS

We restricted our search to the PubMed, PubMed Central, and Web of Science databases to retrieve research articles published in English between January 2009 and August 2019. We focused on quantitative studies that reported positive, negative, or intermediate changes in patient safety outcomes using AI apps, specifically those based on machine-learning algorithms and natural language processing. Quantitative studies reporting only AI performance but not its influence on patient safety outcomes were excluded from further review.

RESULTS

We identified 53 eligible studies, which were summarized concerning their patient safety subcategories, the most frequently used AI, and reported performance metrics. Recognized safety subcategories were clinical alarms (n=9; mainly based on decision tree models), clinical reports (n=21; based on support vector machine models), and drug safety (n=23; mainly based on decision tree models). Analysis of these 53 studies also identified two essential findings: (1) the lack of a standardized benchmark and (2) heterogeneity in AI reporting.

CONCLUSIONS

This systematic review indicates that AI-enabled decision support systems, when implemented correctly, can aid in enhancing patient safety by improving error detection, patient stratification, and drug management. Future work is still needed for robust validation of these systems in prospective and real-world clinical environments to understand how well AI can predict safety outcomes in health care settings.

Robotic surgery of head and neck cancers, a narrative review

Head and neck cancers are the most common cancers in the body. Treatments are determined on the basis of the location and stage of the primary tumor. The goal of treatment is to eliminate the tumor, prevent recurrence or metastasis, and maintain the quality of life. There are several treatments available for the management of head and neck cancers, including surgery, radiation therapy, chemotherapy, new molecular agents, and a combination of them. Transoral robotic technique is a short-time operation using a type of robotic machine in which the patient undergoes anesthesia for a shorter time and the side effects of this operation and the time of hospitalization are less than open surgery. Due to the importance of speed and accuracy in head and neck cancer surgery and the importance of application of robotics in surgery, the present study was designed and implemented to review the application of robotics in the management of head and neck cancers. In this review study, the keywords: application, robotic, surgical, head cancer, transoral robotic surgery (TORS), and neck cancer, were searched in ISI, PubMed, Scopus, Google scholar databases. Related articles written domestically or abroad that have covered areas such as the background of transoral robotic surgery, maintaining organ function and approaches, the advantages and disadvantages of TORS, the affordability of TORS, the combination of TORS with other therapeutic approaches published from 2003 to 2019 were reviewed. The use of robotic surgery for precise operations such as head and neck cancers seems to be essential. More advanced robotic devices are expected to expand the surgery treatment for head and neck cancers as well as the results of using TORS for oncologic optimization and acceptability of results while maintaining organ function and patient's quality of life.

Transoral robotic surgery in head and neck district: a retrospective study on 67 patients treated in a single center

BACKGROUND

The anatomical complexity of the oropharynx and the difficulty in reaching its distal portion have always conditioned the surgical accessibility.Robotic surgery represents an excellent alternative in the treatment of cervico-facial oncological diseases.

METHODS

This series comprises all patients managed for head and neck cancer by Trans Oral Robotic Surgery TORS.The staging assessment, including neck ultrasound and total body PET/CT scan, was performed in each patient according to the TNM classification.All charts were recorded with the following data: name and surname, age, gender, date of surgery intra or post-operative hemorragia, tumor site, histology, TNM stage, robot set-up time, tumor resection time, whether or not tracheotomy was performed, whether or not neck dissection was performed, insertion of a nasogastric tube or gastrostomy, time to resumption of oral feeding, surgical margins, mean length of hospital stay, adjuvant treatment and follow-up.

RESULTS

From February 2013 to February 2018, TORS was performed in 67 consecutive patients affected by head and neck tumours.We divided, our sample, in 3 subsites: supraglottic larynx, parapharyngeal space and oropharynx.Pathology reports confimed malignancy in 44 cases: 8 cases lymphomas, 36 cases of Squamous cell carcinoma (SCC), 5 cases of benign salivary glands tumors and 18 miscellaneous cases. Neck dissection was performed in 12 cases.Tracheotomy was perfomed in 3/67 cases for respiratory failures. A nasogastric tube was inserted at the end of the surgical procedure in 21 patients. The mean length of hospital stay was 10 days .Major complications included post-operative bleeding in 3 patients, 1 exitus for massive bleeding 20 days post-surgery and 1 respiratory failure treated with tracheotomy and monitoring in the Intensive Care Unit (ICU) for 3 days.

CONCLUSIONS

Robotic surgery has been considered a valid alternative to traditional open treatment in many specializations with the advantages of an endoscopic procedure, with the same oncological and functional results and with fewer complications. The advantages of this type of surgical technique have been discussed, it is mandatory to focus on the indications and contraindications.

Nanomedical detection and downstream analysis of circulating tumor cells in head and neck patients

The establishment of novel biomarkers in liquid biopsies of cancer patients has come more into focus in prognostic and diagnostic research efforts. Due to their prognostic relevance disseminated tumor cells or circulating tumor cells are the subject of intensive research and are discussed as early diagnostic indicators for treatment failure and the formation of micrometastases. A potential association of this early-systemic tumor component with poor prognosis of cancer patients could be already demonstrated for various entities including breast, colon, lung, melanoma, ovarian and prostate cancers. Thus, the detection of circulating tumor cells seems to be also applicable for minimal-invasive monitoring of therapy progress in head and neck cancer patients. A major problem of the use in clinical routine is that circulating tumor cells could not be detected by modern imaging techniques. To overcome these limitations highly sensitive detection methods and techniques for their molecular characterization are urgently needed allowing mechanistic understanding and targeting of circulating tumor cells. Especially the medical application of nanotechnology (nanomedical methods) has made valuable contributions to the field. Here, we want to provide a comprehensive overview on (nanomedical) detection methods for circulating tumor cells and discuss their merits, pitfalls and future perspectives especially for head and neck solid squamous cell carcinoma (HNSCC) patients.

Robotic surgery of head and neck cancers, a narrative review

Head and neck cancers are the most common cancers in the body. Treatments are determined on the basis of the location and stage of the primary tumor. The goal of treatment is to eliminate the tumor, prevent recurrence or metastasis, and maintain the quality of life. There are several treatments available for the management of head and neck cancers, including surgery, radiation therapy, chemotherapy, new molecular agents, and a combination of them. Transoral robotic technique is a short-time operation using a type of robotic machine in which the patient undergoes anesthesia for a shorter time and the side effects of this operation and the time of hospitalization are less than open surgery. Due to the importance of speed and accuracy in head and neck cancer surgery and the importance of application of robotics in surgery, the present study was designed and implemented to review the application of robotics in the management of head and neck cancers. In this review study, the keywords: application, robotic, surgical, head cancer, transoral robotic surgery (TORS), and neck cancer, were searched in ISI, PubMed, Scopus, Google scholar databases. Related articles written domestically or abroad that have covered areas such as the background of transoral robotic surgery, maintaining organ function and approaches, the advantages and disadvantages of TORS, the affordability of TORS, the combination of TORS with other therapeutic approaches published from 2003 to 2019 were reviewed. The use of robotic surgery for precise operations such as head and neck cancers seems to be essential. More advanced robotic devices are expected to expand the surgery treatment for head and neck cancers as well as the results of using TORS for oncologic optimization and acceptability of results while maintaining organ function and patient's quality of life.

Deintensification of Adjuvant Treatment After Transoral Surgery in Patients With Human Papillomavirus-Positive Oropharyngeal Cancer: The Conception of the PATHOS Study and Its Development

PATHOS is a phase II/III randomized controlled trial (RCT) of risk-stratified, reduced intensity adjuvant treatment in patients undergoing transoral surgery (TOS) for human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC). The study opened in the UK in October 2015 and, after successful recruitment into the phase II, transitioned into phase III in the autumn of 2018. PATHOS aims to establish whether the de-intensification of adjuvant treatment in patients with favorable prognosis HPV-positive OPSCC will confer improved swallowing outcomes, whilst maintaining high rates of cure. In this article, we will outline the rationale for the study and how it aims to answer fundamentally important questions about the safety, effectiveness and functional outcomes of minimally invasive TOS techniques followed by adjuvant radiotherapy (RT) or chemo-radiotherapy (CRT) in this patient population.

Current Role of Surgery in the Management of Oropharyngeal Cancer

In the last few decades, the surgical treatment of oropharyngeal squamous cell carcinoma (OPSCC) has undergone enormous changes. Until the 1990s, open surgery was the primary treatment for OPSCC. However, due to the potentially severe functional morbidity of this approach, open surgery was largely displaced by concurrent chemoradiotherapy (CRT) in the 1990s. At the same time, new, less-invasive surgical approaches such as transoral surgery with monopolar cautery began to emerge, with the potential to reduce functional morbidity and avoid the late-onset toxicity of CRT. More recently, the growing incidence of HPV-positive disease has altered the patient profile of OPSCC, as these patients tend to be younger and have a better long-term prognosis. Consequently, this has further bolstered interest in minimally-invasive techniques to de-intensify treatment to reduce long-term toxicity and treatment-related morbidity. In this context, there has been a renewed interest in the primary surgery, which allows for accurate pathologic staging and thus—potentially—de-intensification of postoperative CRT. The continuous advances in minimally-invasive surgical approaches, including transoral laser microsurgery (TLM) and transoral robotic surgery (TORS), have also altered the surgical landscape. These minimally-invasive approaches offer excellent functional outcomes, without the severe toxicity associated with intensive CRT, thus substantially reducing treatment-related morbidity. In short, given the increasing prevalence of HPV-positive OPSCC, together with the severe long-term sequela of aggressive CRT, surgery appears to be recapturing its previous role as the primary treatment modality for this disease. While a growing body of evidence suggests that TLM and TORS offer oncologic outcomes that are comparable to CRT and open surgery, many questions remain due to the lack of prospective data. In the present review, we explore the emerging range of surgical options and discuss future directions in the treatment of OPSCC, including the most relevant clinical trials currently underway.

Functional Organ Preservation Surgery in Head and Neck Cancer: Transoral Robotic Surgery and Beyond

In recent years, interest in functional organ preservation surgery (FOPS) in the treatment of head and neck cancer has increased dramatically as clinicians seek to minimize the adverse effects of treatment while maximizing survival and quality of life. In this context, the use of transoral robotic surgery (TORS) is becoming increasingly common. TORS is a relatively new and rapidly-evolving technique, with a growing range of treatment indications. A wide range of novel, flexible surgical robots are now in development and their commercialization is expected to significantly expand the current indications for TORS. In the present review, we discuss the current and future role of this organ-preserving modality as the central element in the multimodal treatment of head and neck cancer.

A Review of HPV-Related Head and Neck Cancer

Head and neck squamous cell carcinomas (HNSCCs) arise in the mucosal lining of the upper aerodigestive tract. Tobacco and alcohol use have been reported to be associated with HNSCC. Infection with high-risk human papillomaviruses (HPVs) has recently been implicated in the pathogenesis of HNSCCs. It is now widely accepted that high-risk HPV is a cause of almost all cervical cancers as well as some forms of HNSCCs. HPV-related HNSCCs are increasing. HPV-related HNSCCs and HPV-unrelated HNSCCs differ with respect to the molecular mechanisms underlying their oncogenic processes. HPV-related HNSCCs are known to have a better prognosis response to treatment as compared with HPV-unrelated HNSCCs. Therefore, in recent years, it has been required to accurately discriminate between HPV-related and HPV-unrelated HNSCCs. To diagnose the HPV-related HNSCCs, various methods including P16 immunohistochemistry, FISH, and genetic analyses of the HPV gene from histopathological and liquid biopsy specimens have been employed. Based on the results of the differential diagnosis, various treatments employing EGFR TKI and low-dose radiation have been employed. Here, we review the involvement of the HPV virus in HNSCCs as well as the molecular mechanism of carcinogenesis, classification, prognosis, diagnostic procedures, and therapy of the disease.

Preoperative predictors of difficult hypopharyngeal exposure by retractor for transoral robotic surgery

Introduction

Transoral endoscopic surgeries provide excellent oncologic outcomes while preserving speech and swallowing ability. However, feasibility has been a major concern about transoral surgery. Therefore, ensuring visualization of the surgical field and sufficient working space is required. The aim of this study was to evaluate the parameters in the preoperative assessment that affect hypopharyngeal exposure.

Methods

Before transoral surgery, parameters regarding the patient’s neck and face such as modified Mallampati index, thyroid–mental distance (TMD), and ability to fully open the mouth were evaluated. Cephalometry and cervical spine radiography were performed preoperatively to evaluate the size of the mandible bone, mouth opening, and cervical spine extension. Mandibular bone parameters such as intergonion distance, mental–gonion distance, articulare–gonion distance, and aperture angle were measured. According to hypopharyngeal exposure using FKWO retractor, patients were divided into difficult hypopharyngeal exposure group (DHE) and non-difficult hypopharyngeal exposure group (non-DHE). Parameters were enrolled to evaluate the relationship between these parameters and DHE status.

Results

This study included 51 patients, 37 in the non-DHE group and 14 in the DHE group. On radiographic evaluation, there was a significant difference in the degree of cervical lordosis between non-DHE and DHE patients. A significantly higher proportion of DHE patients had a history of radiotherapy compared with non-DHE patients.

Conclusion

Patients with limited cervical extension and a history of previous radiotherapy might have difficult hypopharyngeal exposure during transoral surgery. This is the first report to suggest a classification system for hypopharyngeal exposure during transoral surgery.

Outcomes of transoral laser microsurgery for oropharyngeal squamous cell carcinoma in Ireland and review of the literature on transoral approaches

BACKGROUND

The optimal treatment for oropharyngeal squamous cell carcinoma (OPSCC) is controversial. There is increasing evidence that, in selected cases, minimally invasive transoral surgery can offer improved functional outcomes, with equivalent oncologic outcomes, compared to chemoradiotherapy.

AIMS

We report the outcomes of transoral laser microsurgery (TLM) for treatment of OPSCC at our institution.

METHODS

Patients with OPSCC undergoing TLM at the South Infirmary Victoria University Hospital, Cork, between 2010 and 2016, were identified from an institutional database. Human papillomavirus (HPV) status was determined by p16 immunohistochemistry. Survival outcomes were analysed using the Kaplan-Meier method. Complications following surgery and gastrostomy tube dependence were evaluated.

RESULTS

The study cohort consisted of 26 patients, with mean age of 56 years (range 29-71). Primary tumours were located in the tonsil (18), base of tongue (4) and other subsites (4). Seventeen cases were p16-positive. Complications included haemorrhage necessitating return to theatre (1) and aspiration pneumonia (1). Four patients underwent tracheostomy, all of whom were successfully decannulated. One patient underwent gastrostomy tube insertion during postoperative radiotherapy. No patient was gastrostomy dependent at latest follow-up. Twenty-two patients received adjuvant treatment, with radiation alone (21) or chemoradiotherapy (2). Mean follow-up was 27 months. Five-year locoregional control was 92% and disease-specific survival was 81%.

CONCLUSIONS

In selected patients with OPSCC, TLM offers excellent functional and survival outcomes, and as such offers an alternative approach to chemoradiotherapy as primary treatment. We compare TLM to other transoral approaches and discuss its potential use in the Irish healthcare system.

Prospective in silico study of the feasibility and dosimetric advantages of MRI-guided dose adaptation for human papillomavirus positive oropharyngeal cancer patients compared with standard IMRT

PURPOSE

We aim to determine the feasibility and dosimetric benefits of a novel MRI-guided IMRT dose-adaption strategy for human papillomavirus positive (HPV+) oropharyngeal squamous cell carcinoma (OPC).

MATERIALS/METHODS

Patients with locally advanced HPV+ OPC underwent pre-treatment and in-treatment MRIs every two weeks using RT immobilization setup. For each patient, two IMRT plans were created (i.e. standard and adaptive). The prescription dose for the standard plans was 2.12 Gy/fx for 33 fractions to the initial PTV. For adaptive plans, a new PTVadaptive was generated based on serial MRIs in case of detectable tumor shrinkage. Prescription dose to PTVadaptive was 2.12 Gy/fx to allow for maximum dose to the residual disease. Any previously involved volumes received minimally a floor dose of 50.16 Gy. Uninvolved elective nodal volumes were prescribed 50.16 Gy in 1.52 Gy/fx. Dosimetric parameters of organs at risk (OARs) were recorded for standard vs. adaptive plans. Normal tissue complication probability (NTCP) for toxicity endpoints was calculated using literature-derived multivariate logistic regression models.

RESULTS

Five patients were included in this pilot study, 3 men and 2 women. Median age was 58 years (range 45-69). Three tumors originated at the tonsillar fossa and two at the base of tongue. The average dose to 95% of initial PTV volume was 70.7 Gy (SD,0.3) for standard plans vs. 58.5 Gy (SD,2.0) for adaptive plans. The majority of OARs showed decrease in dosimetric parameters using adaptive plans vs. standard plans, particularly swallowing related structures. The average reduction in the probability of developing dysphagia ≥ grade2, feeding tube persistence at 6-month post-treatment and hypothyroidism at 1-year post-treatment was 11%, 4%, and 5%, respectively. The probability of xerostomia at 6-month was only reduced by 1% for adaptive plans vs. standard IMRT.

CONCLUSION

These in silico results showed that the proposed MRI-guided adaptive approach is technically feasible and advantageous in reducing dose to OARs, especially swallowing musculature.

Swallowing after transoral surgery for oropharyngeal cancer: comparison with primary chemoradiotherapy outcomes

PURPOSE OF REVIEW

Survival equipoise is recognized between the contemporary surgical and oncological approaches to oropharyngeal squamous cell carcinoma treatment. Primary transoral surgery (TOS) options have emerged that utilize either laser or robotic techniques. Our review presents an overview of the evidence available for swallowing outcomes following TOS approaches and compares these with outcomes following primary oncological management.

RECENT FINDINGS

Meta-analysis of swallow outcomes following TOS or (chemo)radiotherapy is not possible given the heterogeneity of the available data. There are suggestions of less swallowing impairment following primary TOS, but the favourable selection of patients to these case series must be considered.

SUMMARY

Minimizing swallowing impairment following oropharyngeal squamous cell carcinoma treatment, while ensuring oncological efficacy, should be a priority for head and neck healthcare providers. Primary TOS may offer an advantage to patients, but only through a team approach that considers how adjuvant oncological therapy could be tailored to individuals. High-quality clinical trials are in progress that will inform future practice.

Treatment de-escalation for HPV-driven oropharyngeal cancer: Where do we stand?

HPV-driven oropharyngeal cancers have significantly better survival rates than tobacco and alcohol induced head and neck cancers. As HPV-positive patients are younger, healthier and far more likely to survive their disease, long-term treatment side effects are becoming a major issue. This has led the scientific and medical community to reassess the current treatment protocols in order to develop less toxic strategies while maintaining good oncological outcomes. In this article, we discuss the ongoing treatment de-escalation trials and highlight the issues raised by these studies.

Transoral robotic surgery for the base of tongue squamous cell carcinoma: a preliminary comparison between da Vinci Xi and Si

Considering the emerging advantages related to da Vinci Xi robotic platform, the aim of this study is to compare for the first time the operative outcomes of this tool to the previous da Vinci Si during transoral robotic surgery (TORS), both performed for squamous cell carcinomas (SCC) of the base of tongue (BOT). Intra- and peri-operative outcomes of eight patients with early stage (T1-T2) of the BOT carcinoma and undergoing TORS by means of the da Vinci Xi robotic platform (Xi-TORS) are compared with the da Vinci Si group ones (Si-TORS). With respect to Si-TORS group, Xi-TORS group demonstrated a significantly shorter overall operative time, console time, and intraoperative blood loss, as well as peri-operative pain intensity and length of mean hospital stays and nasogastric tube positioning. Considering recent advantages offered by surgical robotic techniques, the da Vinci Xi Surgical System preliminary outcomes could suggest its possible future routine implementation in BOT squamous cell carcinoma procedures.

Survival and Gastrostomy Prevalence in Patients With Oropharyngeal Cancer Treated With Transoral Robotic Surgery vs Chemoradiotherapy

IMPORTANCE

Treatment of oropharyngeal squamous cell carcinoma (OPSCC) presents unique challenges and can be associated with significant morbidity. Transoral robotic surgery (TORS) has emerged as a treatment modality for OPSCC, but data comparing outcomes between patients treated with TORS-based therapy and nonsurgical therapy are limited.

OBJECTIVE

To compare survival and gastrostomy prevalence between patients with OPSCC treated with TORS-based therapy and those treated with nonsurgical therapy.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective matched-cohort study identified patients with OPSCC treated at the University of Washington and University of Minnesota tertiary care medical centers from January 1, 2005, to December 31, 2013. Each patient treated with TORS-based therapy was matched by stage with as many as 3 patients treated with nonsurgical therapy. Final follow-up was completed on April 1, 2015.

MAIN OUTCOMES AND MEASURES

Disease-free survival, overall survival, and gastrostomy tube prevalence.

RESULTS

One hundred twenty-seven patients met the study criteria (113 men [89.0%]; 14 women [11.0%]; median [interquartile range] age, 57 [52-63] years); 39 patients who underwent TORS were matched to 88 patients who underwent nonsurgical therapy. Compared with the nonsurgical group, more patients had p16-positive tumors in the TORS group (30 of 31 [96.8%] vs 30 of 37 [81.1%] among patients with known p16 status). No statistically significant difference in survival between treatment groups was found in multivariable analysis (disease-free survival hazard ratio, 0.22; 95% CI, 0.04-1.36; P = .10). Patients who received TORS-based therapy had lower gastrostomy tube prevalence after treatment (13 of 39 [33.3%] vs 74 of 88 [84.1%]) for a univariable relative risk of 0.43 (95% CI, 0.27-0.67; P < .001) and a multivariable relative risk of 0.43 (95% CI, 0.27-0.68; P < .001). Gastrostomy prevalence decreased by time after treatment for both groups (TORS group: 3 of 34 [9%] at 3 months to 1 of 33 [3%] at 12 months; nonsurgical group: 37 of 82 [45%] at 3 months to 7 of 66 [11%] at 12 months).

CONCLUSIONS AND RELEVANCE

Patients undergoing TORS for OPSCC have statistically indistinguishable survival but lower gastrostomy prevalence compared with patients undergoing nonsurgical therapy for stage-matched OPSCC. TORS offers promise for improved swallowing function in patients with OPSCC.

The Role of Conventional Surgery in Oropharyngeal Cancer

Anatomically, the oropharynx can be divided into four subsites: the soft palate, pharyngeal wall, base of tongue, and the tonsillar complex. Surgical access to these tumours is often challenging due to the anatomic localization. For this reason, such tumours were traditionally managed with open surgical techniques, usually involving a mandibulotomy, to provide better visualization and access to the oropharynx, followed by free-flap reconstruction of the oropharyngeal defect. However, the invasiveness of this approach could lead to significant morbidity, including speech, swallowing, and airway dysfunction, in addition to poor cosmetic outcomes. In response, less invasive approaches (Mercante et al. 2013) have been developed including minimally invasive surgical approaches (chiefly transoral surgery) as well as non-surgical methods, primarily radiotherapy, and chemotherapy (Mercante et al. 2013).

De-intensification of adjuvant therapy in human papillomavirus-associated oropharyngeal cancer

Current adjuvant treatment guidelines for oropharyngeal squamous cell carcinoma treated with primary surgery are based on studies that predate the human papillomavirus (HPV) era. HPV-associated oropharynx carcinoma (HPV-OPC) has a much more favorable prognosis compared to HPV-unassociated cancer and is increasingly considered to be a distinct disease entity due to its unique etiology, presentation, and behavior. Currently, there is significant interest in adjuvant treatment de-intensification of HPV-OPC patients in order to reduce treatment-related toxicity while maintaining excellent clinical outcomes. Here, we review the evidence and rationale underlying the ongoing prospective trials of adjuvant treatment de-intensification for HPV-OPC patients.

Fluorescence Identification of Head and Neck Squamous Cell Carcinoma and High-Risk Oral Dysplasia With BLZ-100, a Chlorotoxin-Indocyanine Green Conjugate

IMPORTANCE

Surgical cure of head and neck squamous cell carcinoma (HNSCC) remains hampered by inadequately resected tumors and poor recognition of lesions with malignant potential. BLZ-100 is a chlorotoxin-based, tumor-targeting agent that has not yet been studied in HNSCC.

OBJECTIVE

To evaluate BLZ-100 uptake in models of HNSCC and oral dysplasia.

DESIGN, SETTING, AND PARTICIPANTS

This was an observational study (including sensitivity and specificity analysis) of BLZ-100 uptake in an orthotopic xenograft mouse model of HNSCC and a carcinogen-induced dysplasia model of hamster cheek pouches.

INTERVENTIONS

Various HNSCC xenografts were established in the tongues of NOD-scid IL2Rgammanull (NSG) mice. BLZ-100 was intravenously injected and fluorescence uptake was measured. To induce dysplasia, the carcinogen 7,12-dimethylbenz(a)anthracene (DMBA) was applied to the cheek pouch of Golden Syrian hamsters for 9 to16 weeks. BLZ-100 was subcutaneously injected, and fluorescence uptake was measured.

MAIN OUTCOMES AND MEASURES

The signal-to-background ratio (SBR) of BLZ-100 was measured in tumor xenografts. To calculate the sensitivity and specificity of BLZ-100 uptake, a digital grid was placed over tissue sections and correlative histologic sections to discretely measure fluorescence intensity and presence of tumor; a receiver operating characteristic (ROC) curve was then plotted. In the hamster dysplasia model, cheeks were graded according to dysplasia severity. The SBR of BLZ-100 was compared among dysplasia grades.

RESULTS

In HNSCC xenografts, BLZ-100 demonstrated a mean (SD) SBR of 2.51 (0.47). The ROC curve demonstrated an area under the curve (AUC) of 0.89; an SBR of 2.50 corresponded to 92% sensitivity and 74% specificity. When this analysis was focused on the tumor and nontumor interface, the AUC increased to 0.97; an SBR of 2.50 corresponded to 95% sensitivity and 91% specificity. DMBA treatment of hamster cheek pouches generated lesions representing all grades of dysplasia. The SBR of high-grade dysplasia was significantly greater than that of mild-to-moderate dysplasia (2.31 [0.71] vs 1.51 [0.34], P = .006).

CONCLUSIONS AND RELEVANCE

BLZ-100 is a sensitive and specific marker of HNSCC and can distinguish high-risk from low-risk dysplasia. BLZ-100 has the potential to serve as an intraoperative guide for tumor margin excision and identification of premalignant lesions.

Considerations in surgical versus non-surgical management of HPV positive oropharyngeal cancer

Given the marked difference in clinical presentation and treatment response based on human papilloma virus (HPV) status, HPV-associated oropharyngeal squamous cell carcinoma is now viewed as a distinct biologic and clinical entity. HPV-associated oropharyngeal squamous cell carcinoma has increased by nearly 7.5 % per year, from approximately 16 % in the early 1980′s to nearly 70 % today, and is believed will continue to increase dramatically in the coming years. Currently, a myriad of treatment options exist for these patients as many active clinical trials are underway which aim to identify the most appropriate interventions for this unique group of patients. This review aims to provide considerations between surgical and non-surgical management for HPV-associated oropharyngeal squamous cell carcinoma.

Preliminary study of transoral robotic surgery for pharyngeal cancer in Japan

Transoral robotic surgery (TORS) with the da Vinci Surgical System has been used for the removal of pharyngeal and laryngeal cancers with the objective to improve functional and aesthetic outcomes without worsening survival. While TORS has been approved in many countries, Japan's FDA has not yet done so. Our hospital started using TORS with the approval of the Ethical Review Board and the Minimum Invasive Surgical Center Committee at Tottori University. No surgical outcomes of TORS for Japanese patients with head and neck cancer have been reported in Japan. This paper deals with the outcomes and feasibility of TORS for Japanese patients with pharyngeal cancer at our institution. TORS was performed for 10 patients with T1, T2, T3 oropharyngeal and hypopharyngeal squamous cell carcinoma between 2013 and 2014. This is a single-institutional study. TORS could be completed for all cases, except one patient that was not candidate, and no intraoperative conversion to an open surgical procedure was required. Five patients underwent neck dissection, two of them concurrent and three staged. Of all patients, positive surgical margins were detected in two. The average blood loss including neck dissection was 21.5 ± 33.4 ml, the operation time was 183 ± 36 min and the console time was 103 ± 22 min. No tracheostomy had been performed either pre- or postoperatively, and there was no difference between preoperative and postoperative swallowing functions. In this single-institutional preliminary study, we demonstrated that TORS is a feasible and safe treatment. A clinical multi-institutional study of TORS for laryngopharyngeal cancer has been approved as an advanced medical system study and is under way. In the near future, it is expected that the efficacy and safety of TORS for laryngopharyngeal cancer will be confirmed as the result of this multiple-institutional clinical study in Japan.

Mechanical evaluation of newly developed mouthpiece using polyethylene terephthalate glycol for transoral robotic surgery

Transoral robotic surgery (TORS), performed with the da Vinci surgical system (da Vinci), has been classified as a surgical approach for benign and malignant lesions of the oral cavity and laryngopharynx. It provides several unique advantages, which include a three-dimensional magnified view, ability to see and work around curves or angles, and the availability of two or three robotic arms. At present, however, the da Vinci surgical system does not provide haptic feedback. The potential risks specific to the transoral use of the da Vinci include tooth injury, mucosal laceration, ocular injury, and mandibular fracture. To prevent such intra-operative tooth injuries, we created a mouthpiece made of polyethylene terephthalate glycol (PETG) individually shaped for the patient’s teeth. We compared the safety and efficacy of the PETG mouthpiece with those of a conventional mouthpiece made of ethylene–vinyl acetate (EVA). To determine the difference in tooth injury resulting from the two types of mouthpiece, we constructed an experimental system to measure load and strain. We measured the dynamic load and the strain from the rod to the tooth using the PETG and EVA mouthpiece. The rod was pressed against the tooth model outfitted with two types of mouthpiece and the dynamic load was measured with a load cell and the strain with a strain gage. The maximum dynamic load was 1.29 ± 0.03 kgf for the PETG mouthpiece and 2.24 ± 0.05 kgf for the EVA mouthpiece. The load against the tooth was thus less for the EVA mouthpiece. The strain was −166.84 ± 3.94 and 48.24 ± 7.77 με, respectively, while the load direction was parallel to that of the tooth axis for the PETG mouthpiece and perpendicular to the tooth axis for the EVA mouthpiece. The PETG mouthpiece reduced the tooth load compared with the EVA mouthpiece and the load direction was in parallel to the tooth axis. The PETG mouthpiece thus enhances tooth safety for TORS.

Management of locally advanced HPV-related oropharyngeal squamous cell carcinoma: where are we?

HPV-related (HPV+) oropharyngeal cancer (OPC) has a better prognosis compared to HPV unrelated (HPV-) OPC. This review summarizes and discusses several of the controversies regarding the management of HPV+ OPC, including the mechanism of its treatment sensitivity, modern surgical techniques, chemotherapy regimens, and treatment de-intensification protocols. We also discuss and reconsider potential adverse prognostic factors such as tumor EGFR expression, tumor hypoxia, and patient smoking history, as well as the significance of retropharyngeal adenopathy. Finally, we discuss elective nodal treatment of uninvolved lymph node stations. While this review does not exhaust all controversies related to the management of HPV+ OPC, it aims to highlight some of the most clinically relevant ones.

Transoral robotic surgery vs. radiotherapy for management of oropharyngeal squamous cell carcinoma - A systematic review of the literature

BACKGROUND

Intensity-modulated radiation therapy (IMRT) with or without concurrent chemotherapy is widely utilized for the treatment of oropharyngeal squamous cell carcinoma (OPSCC). However, due to significant acute and late toxicities there has been increasing interest in minimally invasive surgical approaches, particularly transoral robotic surgery (TORS) in an attempt to preserve patient quality of life while maintaining oncologic outcomes. The aim of this study was to review the current literature in order to compare primary IMRT versus TORS in the management of OPSCC.

METHODS

A MEDLINE search was conducted to identify studies reporting on the outcomes of TORS or IMRT in the treatment of OPSCC. Reference lists were also reviewed for relevant articles. Oncologic, functional, and quality of life data is summarized and discussed.

RESULTS

One hundred-ninety papers were identified through the MEDLINE search. An additional 52 papers were retrieved by hand searching the reference lists. Ultimately, 44 papers were identified that discussed outcomes after IMRT or TORS for OPSCC. No outcomes from randomized trials were identified.

CONCLUSION

No randomized trials comparing TORS versus IMRT to each other were identified. Uncontrolled reports from the current literature suggest comparable oncologic outcomes with TORS compared to IMRT and functional outcomes may be superior. However, the median follow-up was relatively short and the TORS studies included patients with earlier stage OPSCC on average compared to IMRT studies. Prospective, randomized controlled trials and direct, well-matched comparisons are needed to further elucidate the role for TORS in the treatment of oropharyngeal squamous cell carcinoma.

Targeted Therapy in Oropharyngeal Squamous Cell Carcinoma: The Implications of HPV for Therapy

Oropharyngeal cancers caused by human papillomaviruses (HPV) have a different epidemiology, prognosis, genetic mutational landscape, response to treatment, and outcome when compared to HPV-negative cancers. In this review, a summary of our current understanding of HPV in head and neck cancer and the important advances that have shown HPV to be an etiological agent are discussed. HPV-positive and HPV-negative tumors are compared discussing clinicopathological factors, prognosis, outcome following treatment, and the molecular and genetic differences. Currently, the standard of care for oropharyngeal cancer is both surgery and post-operative radiotherapy with or without cisplatin or concurrent chemo-radiotherapy. The latter is used more often, especially in cancers of tonsil and base of tongue. However, there is increased interest in trying to de-intensify treatment and in the development of new treatments to target the underlying different molecular pathways of HPV-positive cancers. The current clinical trials involving surgery, chemotherapy, and radiation therapy are discussed. The new targeted treatments are also summarized. Although there is currently is no evidence from prospective studies to support a change in the treatment algorithm, the treatment options for patients with HPV-positive disease are likely to change in the future.

PATHOS: a phase II/III trial of risk-stratified, reduced intensity adjuvant treatment in patients undergoing transoral surgery for Human papillomavirus (HPV) positive oropharyngeal cancer

BACKGROUND

Human papillomavirus-positive oropharyngeal squamous cell carcinoma is increasing in incidence worldwide. Current treatments are associated with high survival rates but often result in significant long-term toxicities. In particular, long-term dysphagia has a negative impact on patient quality of life and health. The aim of PATHOS is to determine whether reducing the intensity of adjuvant treatment after minimally invasive transoral surgery in this favourable prognosis disease will result in better long-term swallowing function whilst maintaining excellent disease-specific survival outcomes.

METHODS/DESIGN

The study is a multicentre phase II/III randomised controlled trial for patients with biopsy-proven Human papillomavirus-positive oropharyngeal squamous cell cancer staged T1-T3 N0-N2b with a primary tumour that is resectable via a transoral approach. Following transoral surgery and neck dissection, patients are allocated into three groups based on pathological risk factors for recurrence. Patients in the low-risk pathology group will receive no adjuvant treatment, as in standard practice. Patients in the intermediate-risk pathology group will be randomised to receive either standard dose post-operative radiotherapy (control) or reduced dose radiotherapy. Patients in the high-risk pathology group will be randomised to receive either post-operative chemoradiotherapy (control) or radiotherapy alone. The primary outcome of the phase II study is patient reported swallowing function measured using the MD Anderson Dysphagia Inventory score at 12 months post-treatment. If the phase II study is successful, PATHOS will proceed to a phase III non-inferiority trial with overall survival as the primary endpoint.

DISCUSSION

PATHOS is a prospective, randomised trial for Human papillomavirus-positive oropharyngeal cancer, which represents a different disease entity compared with other head and neck cancers. The trial aims to demonstrate that long-term dysphagia can be lessened by reducing the intensity of adjuvant treatment without having a negative impact on clinical outcome. The study will standardise transoral surgery and post-operative intensity-modulated radiotherapy protocols in the UK and develop a gold-standard swallowing assessment panel. An associated planned translational research programme, underpinned by tumour specimens and sequential blood collected as part of PATHOS, will facilitate further empirical understanding of this new disease and its response to treatment.

TRIAL REGISTRATION

This study is registered with ClinicalTrials.gov identifier NCT02215265 .

PATHOS: a phase II/III trial of risk-stratified, reduced intensity adjuvant treatment in patients undergoing transoral surgery for Human papillomavirus (HPV) positive oropharyngeal cancer

BACKGROUND

Human papillomavirus-positive oropharyngeal squamous cell carcinoma is increasing in incidence worldwide. Current treatments are associated with high survival rates but often result in significant long-term toxicities. In particular, long-term dysphagia has a negative impact on patient quality of life and health. The aim of PATHOS is to determine whether reducing the intensity of adjuvant treatment after minimally invasive transoral surgery in this favourable prognosis disease will result in better long-term swallowing function whilst maintaining excellent disease-specific survival outcomes.

METHODS/DESIGN

The study is a multicentre phase II/III randomised controlled trial for patients with biopsy-proven Human papillomavirus-positive oropharyngeal squamous cell cancer staged T1-T3 N0-N2b with a primary tumour that is resectable via a transoral approach. Following transoral surgery and neck dissection, patients are allocated into three groups based on pathological risk factors for recurrence. Patients in the low-risk pathology group will receive no adjuvant treatment, as in standard practice. Patients in the intermediate-risk pathology group will be randomised to receive either standard dose post-operative radiotherapy (control) or reduced dose radiotherapy. Patients in the high-risk pathology group will be randomised to receive either post-operative chemoradiotherapy (control) or radiotherapy alone. The primary outcome of the phase II study is patient reported swallowing function measured using the MD Anderson Dysphagia Inventory score at 12 months post-treatment. If the phase II study is successful, PATHOS will proceed to a phase III non-inferiority trial with overall survival as the primary endpoint.

DISCUSSION

PATHOS is a prospective, randomised trial for Human papillomavirus-positive oropharyngeal cancer, which represents a different disease entity compared with other head and neck cancers. The trial aims to demonstrate that long-term dysphagia can be lessened by reducing the intensity of adjuvant treatment without having a negative impact on clinical outcome. The study will standardise transoral surgery and post-operative intensity-modulated radiotherapy protocols in the UK and develop a gold-standard swallowing assessment panel. An associated planned translational research programme, underpinned by tumour specimens and sequential blood collected as part of PATHOS, will facilitate further empirical understanding of this new disease and its response to treatment.

TRIAL REGISTRATION

This study is registered with ClinicalTrials.gov identifier NCT02215265 .

HPV in oropharyngeal cancer: the basics to know in clinical practice

The incidence of oropharyngeal squamous cell carcinoma (OPSCC) is rising in contrast to the decreasing incidence of carcinomas in other subsites of the head and neck, in spite of the reduced prevalence of smoking. Human papilloma virus (HPV) infection, and in particular type 16 (HPV-16), is now recognized as a significant player in the onset of HPV positive OPSCC, with different epidemiological, clinical, anatomical, radiological, behavioural, biological and prognostic characteristics from HPV negative OPSCC. Indeed, the only subsite in the head and neck with a demonstrated aetiological viral link is, at present, the oropharynx. These observations lead to questions regarding management choices for patients based on tumour HPV status with important consequences on treatment, and on the role of vaccines and targeted therapy over the upcoming years.

Should patients with HPV-positive or negative tumors be treated differently?

The striking rise in the incidence of HPV-related oropharyngeal squamous cell carcinomas and their improved prognosis compared to classical oropharyngeal cancer raises the question as to whether this subset of patients could benefit from less aggressive treatment without compromising efficacy. To achieve that goal, it is critically important to advance our understanding of the behavior of HPV-positive tumors. It is necessary to identify relevant clinical risk factors and to refine the current staging system. Several clinical trials studying various deintensification strategies are currently underway. This review presents some of the most valuable evidence in this regard in an attempt to encourage further exploration of risk stratification and risk-based therapy for patients with oropharyngeal cancer.

Treatment de-escalation in HPV-positive oropharyngeal carcinoma: ongoing trials, critical issues and perspectives

Due to the generally poor prognosis of head and neck squamous cell carcinoma (HNSCC), treatment has been intensified, these last decades, leading to an increase of serious side effects. High-risk human papillomavirus (HR-HPV) infection has been recently etiologically linked to a subset of oropharyngeal squamous cell carcinoma (OPSCC), which is on the increase. These tumors are different, at the clinical and molecular level, when compared to tumors caused by traditional risk factors. Additionally, their prognosis is much more favorable which has led the medical community to consider new treatment strategies. Indeed, it is possible that less intensive treatment regimens could achieve similar efficacy with less toxicity and improved quality of life. Several clinical trials, investigating different ways to de-escalate treatment, are currently ongoing. In this article, we review these main approaches, discuss the rationale behind them and the issues raised by treatment de-escalation in HPV-positive OPSCC.

Transoral Robotic Surgery in the HPV Era

The incidence of oropharyngeal squamous cell carcinoma (OPSCC) has markedly increased over the last three decades mostly due to human papillomavirus (HPV)-related infections. Cancers resulting from HPV infection bear a better prognosis than those that are smoking-related. Because HPV-positive patients are often younger, with lower rates of co-morbid illness and longer overall life expectancies, long-term sequelae of therapy have become an important issue. Treatment of oropharyngeal cancers has typically involved the use of radiation and chemotherapy to avoid the morbidity of open surgery which included mandibulotomy and composite resection. Transoral robotic surgery (TORS) is an emerging treatment option for this disease, avoiding the morbidity of open approaches while providing excellent oncologic and functional outcomes. With overall survival rate at 2 years exceeding 80%, and local failure rate of less than 3%, patients receiving TORS report relatively good health-related quality of life (QOL) scores. The aim of the current review is to provide a summary of the current literature with regard to the oncologic and functional outcomes following treatment of OPSCC with TORS.

Transoral robotic surgery (TORS) for tongue base tumours

In recent years, transoral robotic surgery (TORS) has been used for the removal of pharyngeal and laryngeal cancers with the objective to improve functional and aesthetic outcomes without worsening the survival. This prospective single-centre cohort study described TORS in selected tumours of the tongue base in order to assess safety, efficacy and functional outcome of the procedure. From October 2010 to February 2012, TORS was performed in 13 consecutive patients affected by T1-T2 tumours of the base of the tongue. This procedure was applicable in all cases. The clinical stage demonstrated 8 T1 tumours and 5 T2 tumours. Neck node metastases were clinically evident in 6 cases (7 N0, 1 N1, 4 N2b and 1 N2c). The final pathology report confirmed malignancy in all cases (11 squamous cell carcinoma and 2 mucoepidermoid carcinoma). Negative-margin resections were obtained in all cases but one with close margins. Synchronous lymph node neck dissections were performed in 7 cases (6 monolateral, 1 bilateral). Patients underwent temporary tracheostomies for a mean time of 6 days. A naso-gastric feeding tube was positioned in 10/13 (76.9%) patients for a mean time of 7.5 days. The average time to carry out the TORS procedure was 95 min (set-up time 25 min; TORS 70 min). No deaths occurred. Surgical complications were observed in 4 cases (postoperative bleedings in 3 cases and intraoperative anaphylactic shock in 1 case). Median hospital stay was 9 days. All patients had good functional outcomes. Adjuvant treatment was indicated in 5/13 cases (35.4%). TORS represents a good tool for staging and treating neoplasm of the base of the tongue. The transoral removal is safe and can radically remove limited oropharyngeal tumours of the tongue base with good functional outcomes. The operating costs can be relatively high but they are related to the number of procedures per year, although the advantages to patients seem to justify the procedure. TORS can represent the definitive treatment in selected T1-T2 cases of base of the tongue tumours without adverse features and allow the possibility for the deintensification of adjuvant treatments.

Impact of human papillomavirus on oropharyngeal cancer biology and response to therapy: implications for treatment

Oropharyngeal squamous cell carcinoma (OPSCC) originating from human papillomavirus infection has emerged as a new entity in head and neck cancer, defining a subset of patients with distinct carcinogenesis, risk factor profiles, and clinical presentation that show markedly improved survival than patients with classic OPSCC. De-escalation of therapy and identification of relevant biomarkers to aid in patient selection are actively being investigated. This review addresses the implications of these findings in clinical care.

Oropharyngeal squamous cell carcinoma with known human papillomavirus status treated with definitive chemoradiotherapy: patterns of failure and toxicity outcomes

Background

Tumor human papillomavirus (HPV) status has emerged as one of the most powerful prognostic factors for disease control and survival in patients with oropharyngeal squamous cell carcinoma (OPSCC). We reviewed our experience in patients with OPSCC and known tumor HPV status treated with definitive chemoradiotherapy (CRT).

Methods

Patients with stage III-IVb OPSCC and known tumor HPV status treated with CRT between 2006 and 2011 were identified from an IRB approved registry for this retrospective review. Outcomes were estimated using the Kaplan-Meier method and compared between HPV-positive and negative patients using the log-rank test.

Results

Of the 121 pts (89% male, 93% Caucasian) included in this study, median age was 57 (range: 40–73) and median follow-up was 21 months (range: 6–63). Ninety-seven (80%) patients were HPV-positive and 24 (20%) were HPV-negative. Primary site was base of tongue (55%), tonsil (44%), and oropharyngeal wall (2%). Two year rates of locoregional recurrence (3% vs. 26%; p = 0.002), disease free survival (93% vs. 64%; p = 0.001) and overall survival (94% vs 73%; p = 0.002) were superior in HPV-positive patients, while rates of distant recurrence were similar (3% vs. 5%; p = 0.98). While acute toxicities were similar between both groups, patients with HPV-positive disease were more likely to resume a normal diet (90% vs. 65%; p = 0.017) at last follow up. Also, no HPV-positive patient required a feeding tube beyond 6 months after treatment, compared with 24% of HPV-negative patients.

Conclusions

Definitive CRT produces excellent rates of disease control with minimal late toxicity for patients with HPV-positive OPSCC. Studies of OPSCC should account for tumor HPV status when identifying factors prognostic for outcome.