Radiation therapy quality assurance in head and neck radiotherapy - Moving forward

Enhanced head and neck radiotherapy target definition through multidisciplinary delineation and peer review: A prospective single-center study

This study evaluates the benefit of weekly delineation and peer review by a multidisciplinary team (MDT) of radiation oncologists (ROs), radiologists (RXs), and nuclear medicine (NM) physicians in defining primary and lymph node tumor volumes (GTVp and GTVn) for head and neck cancer (HNC) radiotherapy. This study includes 30 consecutive HNC patients referred for definitive curative (chemo)-radiotherapy. Imaging data including head and neck MRI, [18F]-FDG-PET and CT scan were evaluated by the MDT. The RO identified the 'undeniable' tumor as GTVp_core and determined GTVp_max, representing the maximum tumoral volume. The MDT delineation (MDT-D) by RX and NM physicians outlined their respective primary GTVs (GTVp_RX and GTVp_NM). During the MDT meeting (MDT-M), these contours were discussed to reach a consensus on the final primary GTV (GTVp_final). In the comparative analysis of various GTVp delineations, we performed descriptive statistics and assessed two MDT-M factors: 1) the added value of MDT-M, which includes the section of GTVp_final outside GTVp_core but within GTVp_RX or GTVp_NM, and 2) the part of GTVp_final that deviates from GTVp_max, representing the area missed by the RO. For GTVn, discussions evaluated lymph node extent and malignancy, documenting findings and the frequency of disagreements. The average GTVp core and max volumes were 19.5 cc (range: 0.4-90.1) and 22.1 cc (range: 0.8-106.2), respectively. Compared to GTVp_core, MDT-D to GTVp_final added an average of 3.3 cc (range: 0-25.6) and spared an average of 1.3 cc (0-15.6). Compared to GTVp_max, MDT-D and -M added an average of 2.7 cc (range: 0-20.3) and removed 2.3 cc (0-21.3). The most frequent GTVn discussions included morphologically suspicious nodes not fixing on [18F]-FDG-PET and small [18F]-FDG-PET negative retropharyngeal lymph nodes. Multidisciplinary review of target contours in HNC is essential for accurate treatment planning, ensuring precise tumor and lymph node delineation, potentially improving local control and reducing toxicity.

Facility Volume and Changing Facilities for Postoperative Radiotherapy in Salivary Gland Cancer

OBJECTIVES

Changing location of postoperative radiotherapy (PORT) after treatment at a high-volume facility (HVF) is associated with worse survival in various head and neck cancers. Our study investigates this relationship in salivary gland cancer (SGC).

METHODS

The 2004-2016 National Cancer Database was queried for all cases of adult SGC treated with surgery and PORT with or without adjuvant chemotherapy. Patients with multiple cancer diagnoses, metastatic disease, or unknown PORT facility were excluded. Reporting facilities with >95th percentile annual case volume were classified as HVFs, the remainder were classified low-volume facilities (LVFs).

RESULTS

A total of 7885 patients met inclusion criteria, of which 418 (5.3%) were treated at an HVF. Patients treated at an HVF had higher rates clinical nodal positivity (18.2% vs. 14.0%, p < 0.001) and clinical T3/T4 (27.3% vs. 20.7%, p = 0.001) disease. Patients at HVFs changed facility for PORT at lower rates (18.9% vs. 24.5%, p = 0.009). Patients treated at an HVF had higher 5-year overall survival (5-OS) than those treated at an LVF (79.0% vs. 72.0%, p = 0.042). Patients treated at an HVF that changed PORT facility had worse 5-OS (60.8% vs. 83.2%, p < 0.001). Radiation facility change was an independent predictor of worse survival in patients treated at an HVF (HR: 8.99 [3.15-25.67], p < 0.001) but not for patients treated at a LVF (HR: 1.11 [0.98-1.25], p = 0.109).

CONCLUSIONS

Patients treated at an HVF changing facility for PORT for SGC experience worse survival. Our data suggest patients treated surgically at an HVF should be counseled to continue their PORT at the same institution.

LEVEL OF EVIDENCE

3 Laryngoscope, 2024.

A proposed framework for the implementation of head and neck cancer treatment at a new cancer center from a radiation oncology perspective

BACKGROUND

Establishing a new head and neck cancer (HNC) treatment center requires multidisciplinary team management and expertise. To our knowledge, there are no clear recommendations or guidelines in the literature for the commencement of HNC radiation therapy (RT) at a new cancer center. We propose a novel framework outlining the necessary components required to set-up a new radiation therapy HNC treatment.

METHODS

We reviewed the infrastructure and methodology in the commencement of HNC radiation therapy in our cancer care center and invited several external, experienced metropolitan head and neck radiation oncologists to develop a novel consensus guideline that may be used by new RT centers to treat HNC. Recommendations were presented to our internal and external staff specialists using a survey questionnaire with ratings utilized to determine consensus using pre-defined thresholds as per the American Society of Clinical Oncology Guidelines Methodology Manual.

CONCLUSION

This consensus recommendation aims to improve RT utilization whilst advocating for optimal patient outcomes by presenting a framework for new radiation therapy centers ready to step up and manage the treatment of head and neck cancer patients. We propose these evidence-based consensus guidelines endorsed by external HNC radiation oncologists.

Latin American Consensus on the Treatment of Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) is well known as a serious health problem worldwide, especially in low-income countries or those with limited resources, such as most countries in Latin America. International guidelines cannot always be applied to a population from a large region with specific conditions. This study established a Latin American guideline for care of patients with head and neck cancer and presented evidence of HNSCC management considering availability and oncologic benefit. A panel composed of 41 head and neck cancer experts systematically worked according to a modified Delphi process on (1) document compilation of evidence-based answers to different questions contextualized by resource availability and oncologic benefit regarding Latin America (region of limited resources and/or without access to all necessary health care system infrastructure), (2) revision of the answers and the classification of levels of evidence and degrees of recommendations of all recommendations, (3) validation of the consensus through two rounds of online surveys, and (4) manuscript composition. The consensus consists of 12 sections: Head and neck cancer staging, Histopathologic evaluation of head and neck cancer, Head and neck surgery-oral cavity, Clinical oncology-oral cavity, Head and neck surgery-oropharynx, Clinical oncology-oropharynx, Head and neck surgery-larynx, Head and neck surgery-larynx/hypopharynx, Clinical oncology-larynx/hypopharynx, Clinical oncology-recurrent and metastatic head and neck cancer, Head and neck surgery-reconstruction and rehabilitation, and Radiation therapy. The present consensus established 48 recommendations on HNSCC patient care considering the availability of resources and focusing on oncologic benefit. These recommendations could also be used to formulate strategies in other regions like Latin America countries.

Overcoming inter-observer planning variability in target volume contouring and dose planning for high-risk neuroblastoma - a European multicenter effort of the SIOPEN radiotherapy committee

BACKGROUND AND PURPOSE

To establish an international quality standard for contouring and planning for high-risk neuroblastoma within the prospective High-Risk Neuroblastoma Study 2 of SIOP-Europe-Neuroblastoma (SIOPEN HR-NBL2), which includes a randomized question on dose escalation for residual disease.

MATERIALS AND METHODS

Data on four patients with high-risk neuroblastoma were selected and distributed to the radiotherapy committee of the HR-NBL2 study for independent contouring and planning. Differences in contouring were analyzed using apparent and kappa-corrected agreement. Plans were analyzed regarding the dose-volume histogram metrics. Results were discussed among experts and agreement was obtained.

RESULTS

Substantial agreement was found for contouring of the heart (0.64), liver (0.70), left lung (0.74), and right lung (0.74). For contouring of the gastrointestinal tract (0.54), left kidney (0.60), and right kidney (0.59) moderate agreement was obtained. For target volume delineation, agreement for preoperative tumour extent was moderate (0.42), for CTV fair (0.35) and only low (0.06) for residual tumour, respectively. The dose planning strategies appeared to be relatively homogeneous among all experts.

CONCLUSION

Considerable variability was found for the delineation of target volumes, particularly the boost volume, whereas the contouring of the organs at risk and the planning strategy were reasonably consistent. In order to obtain reliable results from the randomized HR-NBL2 trial, standardization of target volume delineation based on adequate imaging is crucial.

Facility volume and survival: Human papilloma virus positive oropharyngeal squamous cell carcinoma

BACKGROUND

To analyze the impact of facility volume on survival for human papilloma virus positive oropharyngeal squamous cell carcinoma (HPV+ OPSCC) patients.

METHODS

Patients treated for HPV+ OPSCC from 2010 to 2017 were queried from the National Cancer Database. Facilities of average annual case volume <50th percentile were categorized as low-volume (LV) and >95th percentile as high-volume (HV).

RESULTS

11,546 were included, with 10,305 patients (89.3 %) treated at LV and 1241 (10.7 %) at HV facilities. A greater proportion of cases involving resection of base of tongue and lingual tonsil were treated at HV (30.3 %) compared to LV (22.3 %) facilities (p < 0.001). Patients treated at a HV facility had greater percentage of clinical T4 (11.2 % vs. 8.6 %, p = 0.001) and N+ disease (90.5 % vs. 85.7 %, p < 0.001) patients. Survival analysis showed no statistically significant difference between five-year overall survival rates by facility volume (p = 0.388) for all patients. On multivariable analysis, facility volume was not associated with survival (HR: 0.968 [0.758-1.235], p = 0.791). These trends were found for both patients undergoing primary surgery or chemoradiotherapy.

CONCLUSION

Our data indicates that patients with HPV+ OPSCC do not experience a survival benefit with treatment at HV facility, suggesting these patients may be adequately treated at LV centers.

The role of medical physicists in clinical trials across Europe

INTRODUCTION

The roles and responsibilities of medical physicists (MPs) are growing together with the evolving science and technology. The complexity of today's clinical trials requires the skills and knowledge of MPs for their safe and efficient implementation. However, it is unclear to what extent the skillsets offered by MPs are being exploited in clinical trials across Europe.

METHODS

The EFOMP Working Group on the role of Medical Physics Experts in Clinical Trials has designed a survey that targeted all 36 current National Member Organisations, receiving a response from 31 countries. The survey included both quantitative and qualitative queries regarding the involvement of MPs in trial design, setup, and coordination, either as trial team members or principal investigators.

RESULTS

The extent of MPs involvement in clinical trials greatly varies across European countries. The results showed disparities between the roles played by MPs in trial design, conduct or data processing. Similarly, differences among the 31 European countries that responded to the survey were found regarding the existence of national bodies responsible for trials or the available training offered to MPs. The role of principal investigator or co-investigator was reported by 12 countries (39%), a sign of efficient collaboration with medical doctors in designing and implementing clinical studies.

CONCLUSION

Organisation of specific training courses and guideline development for clinical trial design and conduct would encourage the involvement of a larger number of MPs in all stages of trials across Europe, leading to a better standardisation of clinical practice.

Head and neck cancers: Monitoring quality and reporting outcomes

INTRODUCTION

Head and neck cancers (HNC) require high level multidisciplinary care to achieve optimal outcomes. Reporting of quality indicators (QIs) has been instigated by some health services in an effort to improve quality of care. The aim of this study was to determine the quality of care provided to patients with HNC at a single institution by analysing compliance with QIs and to explore the feasibility and utility of collecting this data.

METHODS

This was a single institution retrospective chart review of all patients with squamous cell HNC at Townsville Hospital who were treated with curative intent between June 2011 and June 2019. Data was entered into a RedCap database and then exported to Stata V16 for analysis.

RESULTS

A total of 537 patients were included in the overall study, with six patients who had a synchronous non-HNC and two patients who received previous radiotherapy (RT) to the head and neck region excluded from the outcome analysis. Overall, compliance with pre-treatment, treatment and post-treatment QIs was high, with the exception of smoking cessation support (66%), post-treatment dental review and time to post-operative RT (33% of patients within 6 weeks). The 5-year overall survival was 69.4% (CI; 64-73.2%). The cumulative incidence of locoregional relapse for the overall study cohort was 18% (CI; 14.8-21.4%).

CONCLUSION

Collecting and evaluating quality metrics is feasible and helps identify areas for improvement. Centres treating HNC patients should strive towards monitoring quality against benchmarks and demonstrate transparency in outcome data.

Report on planning comparison of VMAT, IMRT and helical tomotherapy for the ESCALOX-trial pre-study

Background

The ESCALOX trial was designed as a multicenter, randomized prospective dose escalation study for head and neck cancer. Therefore, feasibility of treatment planning via different treatment planning systems (TPS) and radiotherapy (RT) techniques is essential. We hypothesized the comparability of dose distributions for simultaneous integrated boost (SIB) volumes respecting the constraints by different TPS and RT techniques.

Methods

CT data sets of the first six patients (all male, mean age: 61.3 years) of the pre-study (up to 77 Gy) were used for comparison of IMRT, VMAT, and helical tomotherapy (HT). Oropharynx was the primary tumor location. Normalization of the three step SIB (77 Gy, 70 Gy, 56 Gy) was D95% = 77 Gy. Coverage (CVF), healthy tissue conformity index (HTCI), conformation number (CN), and dose homogeneity (HI) were compared for PTVs and conformation index (COIN) for parotids.

Results

All RT techniques achieved good coverage. For SIB77Gy, CVF was best for IMRT and VMAT, HT achieved highest CN followed by VMAT and IMRT. HT reached good HTCI value, and HI compared to both other techniques. For SIB70Gy, CVF was best by IMRT. HTCI favored HT, consequently CN as well. HI was slightly better for HT. For SIB56Gy, CVF resulted comparably. Conformity favors VMAT as seen by HTCI and CN. Dmean of ipsilateral and contralateral parotids favor HT.

Conclusion

Different TPS for dose escalation reliably achieved high plan quality. Despite the very good results of HT planning for coverage, conformity, and homogeneity, the TPS also achieved acceptable results for IMRT and VMAT.

Trial registration ClinicalTrials.gov Identifier: NCT 01212354, EudraCT-No.: 2010-021139-15. ARO: ARO 14-01

Factors Associated With the Choice of Radiation Therapy Treatment Facility in Head and Neck Cancer

OBJECTIVE

To analyze the clinicodemographic characteristics and treatment outcomes of patients receiving postoperative radiation therapy (PORT) at a different treatment facility rather than the initial surgical facility for head and neck cancer.

STUDY DESIGN

Retrospective cohort analysis.

METHODS

Utilizing the National Cancer Data Base, 2004 to 2015, patients with a diagnosis of oral cavity/oropharyngeal, hypopharyngeal, and laryngeal squamous cell carcinoma were studied. Multivariate analysis was completed with multivariate regression and Cox proportional hazard model, and survival outcomes were examined using Kaplan-Meier analysis.

RESULTS

A total of 15,181 patients who had surgery for a head and neck cancer at an academic/research center were included in the study population. Of the study population, 4,890 (32.2%) patients completed PORT at a different treatment facility. Treatment at a different facility was more common among patients who were ≥65 years old, white, Medicare recipients, those with a greater distance between residence and surgical treatment facility, and with lower income within area of residence (each P < .05). Overall survival was worse in patients completing PORT at a different treatment facility versus at the institution where surgery was completed (61.9% vs. 66.4%; P = .002).

CONCLUSIONS

PORT at a different facility was more common in older individuals, Medicare recipients, those with greater distance to travel, and lower-income individuals. Completing PORT outside the hospital where surgery was performed was associated with inferior survival outcomes among head and neck cancer patients.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:1019-1025, 2021.

Saliva electrolyte analysis and xerostomia-related quality of life in nasopharyngeal carcinoma patients following intensity-modulated radiation therapy

BACKGROUND AND PURPOSE

Nasopharyngeal carcinoma (NPC) is one of the most common cancers in southern China and the first-line treatment is radiotherapy. Intensity-modulated radiation therapy (IMRT) can deliver high dose to cancer and low dose to normal tissue, but xerostomia is still one of the complications after IMRT. However, how the concentration of saliva electrolytes be affected by IMRT and the effects on the quality of life are still unknown. In this prospective study, 76 NPC patients were recruited from hospitals in Hong Kong to identify the change of saliva electrolytes and xerostomia-related quality of life before and after IMRT.

METHODS AND MATERIALS

Saliva and questionnaire were collected before IMRT, 1 month, 3 months, 6 months and 12 months after IMRT. The concentration of saliva electrolytes was detected using inductively coupled plasma-optical emission spectroscopy (ICP-OES).

RESULTS

Saliva flow rate significantly decreased after IMRT. Decrease in the mean value of pH was observed but the difference is not statistically significant. The concentrations of potassium, iodine, and calcium decreased and chloride concentration increased after IMRT, while the concentrations of sodium, magnesium, copper or zinc were kept at the same level before and after treatment. Xerostomia-related quality of life was adversely affected by IMRT, but partially recovered after 1 year.

CONCLUSIONS

Our study revealed the change of saliva electrolytes and xerostomia-related quality of life in patients undergone IMRT for NPC.

Quality of Life, Toxicity and Unmet Needs in Nasopharyngeal Cancer Survivors

Concerted research efforts over the last three decades have resulted in improved survival and outcomes for patients diagnosed with nasopharyngeal carcinoma (NPC). The evolution of radiotherapy techniques has facilitated improved dose delivery to target volumes while reducing dose to the surrounding normal tissue, improving both disease control and quality of life (QoL). In parallel, clinical trials focusing on determining the optimal systemic therapy to use in conjunction with radiotherapy have been largely successful, resulting in improved locoregional, and distant control. As a consequence, neoadjuvant chemotherapy (NACT) prior to definitive chemoradiotherapy has recently emerged as the preferred standard for patients with locally advanced NPC. Two of the major challenges in interpreting toxicity and QoL data from the published literature have been the reliance on: (1) clinician rather than patient reported outcomes; and (2) reporting statistical rather than clinical meaningful differences in measures. Despite the lower rates of toxicity that have been achieved with highly conformal radiotherapy techniques, survivors remain at moderate risk of persistent and long-lasting treatment effects, and the development of late radiation toxicities such as hearing loss, cranial neuropathies and cognitive impairment many years after successful treatment can herald a significant decline in QoL. Future approaches to reduce long-term toxicity will rely on: (1) identifying individual patients most likely to benefit from NACT; (2) development of response-adapted radiation strategies following NACT; and (3) anticipated further dose reductions to organs at risk with proton and particle therapy. With increasing numbers of survivors, many in the prime of their adult life, research to identify, and strategies to address the unmet needs of NPC survivors are required. This contemporary review will summarize our current knowledge of long-term toxicity, QoL and unmet needs of this survivorship group.

Proton therapy for head and neck squamous cell carcinomas: A review of the physical and clinical challenges

The quality of radiation therapy has been shown to significantly influence the outcomes for head and neck squamous cell carcinoma (HNSCC) patients. The results of dosimetric studies suggest that intensity-modulated proton therapy (IMPT) could be of added value for HNSCC by being more effective than intensity-modulated (photon) radiation therapy (IMRT) for reducing side effects of radiation therapy. However, the physical properties of protons make IMPT more sensitive than photons to planning uncertainties. This could potentially have a negative effect on the quality of IMPT planning and delivery. For this review, the three French proton therapy centers collaborated to evaluate the differences between IMRT and IMPT. The review explored the effects of these uncertainties and their management for developing a robust and optimized IMPT treatment delivery plan to achieve clinical outcomes that are superior to those for IMRT. We also provide practical suggestions for the management of HNSCC carcinoma with IMPT. Because metallic dental implants can increase range uncertainties (3-10%), patient preparation for IMPT may require more systematic removal of in-field alien material than is done for IMRT. Multi-energy CT may be an alternative to calculate more accurately the dose distribution. The practical aspects that we describe are essential to guarantee optimal quality in radiation therapy in both model-based and randomized clinical trials.

Radiotherapy Quality Assurance for Head and Neck Squamous Cell Carcinoma

The impact of radiotherapy (RT) quality assurance (QA) has been demonstrated by numerous studies and is particularly important for head and neck cancer (HNC) treatment due to the complexity of RT target volumes in this region and the multiple adjacent organs at risk. The RT planning process includes many critical steps including interpretation of diagnostic imaging, image fusion, target volume delineation (tumor, lymph nodes, and organs at risk), and planning. Each step has become highly complex, and precise and rigorous QA throughout the planning process is essential. The ultimate aim is to precisely deliver radiation dose to the target, maximizing the tumor dose and minimizing the dose to surrounding organs at risk, in order to improve the therapeutic index. It is imperative that RT QA programs should systematically control all aspects of the RT planning pathway and include regular end-to-end tests and external audits. However, comprehensive QA should not be limited to RT and should, where possible, also be implemented for surgery, systemic therapy, pathology, as well as other aspects involved in the interdisciplinary treatment of HNC.

Quality of Care Indicators for Head and Neck Cancers: The Experience of the European Project RARECAREnet

Background: Monitoring and improving quality of cancer care has become pivotal today. This is especially relevant for head and neck cancers since the disease is complex, it needs multi therapy, patients tend to be older, they tend to have comorbidities and limited social support. However, information on quality of care for head and neck cancers is scarce. In the context of the project "Information Network on Rare Cancers" we aimed to identify indicators of quality of care specific for the head and neck cancers management and to measure the quality of care for head and neck cancers in different EU Member States. Methods: We defined indicators of quality of care for head and neck cancers based on a multidisciplinary and expert-based consensus process at a European level. To test the proposed indicators, we performed an observational population-based retrospective study in four countries (Ireland, Italy, Netherlands, and Slovenia) in the years 2009-2011. Results: The main quality indicators identified are: availability of formalized multidisciplinary team, participation in clinical and translational research; timeliness of care, high quality of surgery and radiotherapy, and of pathological reporting. For head and neck cancers, the quality of care did not reach the optimal standards in most of the countries analyzed. A high proportion of patients was diagnosed at an advanced disease stage, showed delays in starting treatment (especially for radiotherapy), and there was only a very limited use of multi therapy. Conclusions: According to the achieved consensus, indicators of quality of care for head and neck cancers have to cover the patient journey (i.e., diagnosis and treatment). Our results, showed suboptimal quality of care across countries and call for solutions for ensuring good quality of care for head and neck cancer patients in all EU countries. One possible option might be to refer head and neck cancer patients to specialized centers or to networks including specialized centers.