Decisional Conflict in Patients with Advanced Laryngeal Carcinoma: A Multicenter Study

OBJECTIVES

Decision-making for patients with a locally advanced laryngeal carcinoma (T3 and T4) is challenging due to the treatment choice between organ preservation and laryngectomy, both with different and high impact on function and quality of life (QoL). The complexity of these treatment decisions and their possible consequences might lead to decisional conflict (DC). This study aimed to explore the level of DC in locally advanced laryngeal carcinoma patients facing curative decision-making, and to identify possible associated factors.

METHODS

In this multicenter prospective cohort study, participants completed questionnaires on DC, level of shared decision-making (SDM), and a knowledge test directly after counseling and 6 months after treatment. Descriptive statistics and Spearman correlation tests were used to analyze the data.

RESULTS

Directly after counseling, almost all participants (44/45; 98%) experienced Clinically Significant DC score (CSDC >25, scale 0-100). On average, patients scored 47% (SD 20%) correct on the knowledge test. Questions related to radiotherapy were answered best (69%, SD 29%), whilst only 35% (SD 29%) of the questions related to laryngectomy were answered correctly. Patients' perceived level of SDM (scale 0-100) was 70 (mean, SD 16.2), and for physicians this was 70 (SD 1.7).

CONCLUSION

Most patients with advanced larynx cancer experience high levels of DC. Low knowledge levels regarding treatment aspects indicate a need for better patient counseling.

LEVEL OF EVIDENCE

Level IV Laryngoscope, 2024.

The development of a decision aid for patients with operable oropharyngeal carcinoma in the Netherlands - A mixed methods study

OBJECTIVE

The aim of this project is to create an interactive online patient decision aid (PDA) for oropharyngeal cancer (OPSCC) patients, eligible for transoral (robotic) surgery with an ultimate goal to assist both physicians and patients in making treatment choices.

MATERIALS AND METHODS

Following the International Patient Decision Aid Standards, a mixed-methods approach was employed. The study involved semi-structured in-depth interviews with patients and physicians, thinking-out-loud sessions, and study-specific questionnaires. Thematic coding and analysis were conducted on verbatim transcriptions of audio-recorded interviews.

RESULTS

The PDA drafts were evaluated by twenty OPSCC survivors and twenty multidisciplinary specialists. Significant revisions were made after phase 1 to enhance readability and reduce text, whilst incorporating videos and graphics. Following all phases, both patients and specialists rated the PDA as comprehensible, feasible, and a valuable addition to regular counseling.

CONCLUSION

This study showcases the development of a PDA for early stage oropharyngeal cancer patients considering surgery and radiotherapy options. The decision aid emphasizes the disparities in short- and long-term side effects between the two treatments. Patients and physicians found the decision aid to be understandable, user-friendly, and helpful for future patients. The PDA is available on https://beslissamen.nl/.

Squamous Cell Carcinoma Antigen in the Follow-up of Patients With Head and Neck Cancer

OBJECTIVE

to determine if the tumor marker squamous cell carcinoma antigen (SCC-Ag) observed over time may contribute to the early detection of recurrence, metastasis, and second primary tumors in the follow-up of patients with head and neck squamous cell carcinoma (HNSCC).

STUDY DESIGN

A retrospective analysis of patients with HNSCC and at least one SCC-Ag measurement was conducted. Hazard ratios (HRs) were used to determine the correlation between SCC-Ag and an event.

SETTING

patients with HNSCC, treated in the Antoni van Leeuwenhoek Hospital in The Netherlands between 2010 and 2020 were used for the analysis.

METHODS

Data from 789 patients were used on event-free survival (EFS) with time-dependent Cox models. In addition to current (most recent) SCC-Ag (also dichotomized into high and low as done for clinical practice), average SCC-Ag and change between SCC-Ag measurements (delta SCC-Ag) were considered, using restricted cubic splines to explore nonlinear relationships.

RESULTS

Dichotomized SCC-Ag values (HR = 3.01, 95% confidence interval [CI]: 2.17-4.18) and the delta SCC-Ag (HR = 1.15, 95% CI: 1.07-1.22) predicted EFS better than models using the cumulative average or current value of SCC-Ag, also after adjusting for tumor site, stage, age, and gender. A strong association was observed when using delta SCC-Ag as a linear predictor in the subgroup of oropharynx patients (HR = 4.88, 95% CI: 2.71-8.79).

CONCLUSION

Dichotomized and delta SCC-Ag values can be important markers for EFS, during the follow-up of patients treated for HNSCC. These results were more evident in patients with oropharyngeal cancer.

Personalized neck irradiation guided by sentinel lymph node biopsy in patients with squamous cell carcinoma of the oropharynx, larynx or hypopharynx with a clinically negative neck: (Chemo)radiotherapy to the PRIMary tumor only. Protocol of the PRIMO study

Background

Elective neck irradiation (ENI) is performed in head and neck cancer patients treated with definitive (chemo)radiotherapy. The aim is to eradicate nodal metastases that are not detectable by pretreatment imaging techniques. It is conceivable that personalized neck irradiation can be performed guided by the results of sentinel lymph node biopsy (SLNB). It is expected that ENI can be omitted to one or both sides of the neck in 9 out of 10 patients, resulting in less radiation side effects with better quality of life.

Methods/design

This is a multicenter randomized controlled trial aiming to compare safety and efficacy of treatment with SLNB guided neck irradiation versus standard bilateral ENI in 242 patients with cN0 squamous cell carcinoma of the oropharynx, larynx or hypopharynx for whom bilateral ENI is indicated. Patients randomized to the experimental-arm will undergo SLNB. Based on the histopathologic status of the SLNs, patients will receive no ENI (if all SLNs are negative), unilateral neck irradiation only (if a SLN is positive at one side of the neck) or bilateral neck irradiation (if SLNs are positive at both sides of the neck). Patients randomized to the control arm will not undergo SLNB but will receive standard bilateral ENI. The primary safety endpoint is the number of patients with recurrence in regional lymph nodes within 2 years after treatment. The primary efficacy endpoint is patient reported xerostomia-related quality of life at 6 months after treatment.

Discussion

If this trial demonstrates that the experimental treatment is non-inferior to the standard treatment in terms of regional recurrence and is superior in terms of xerostomia-related quality of life, this will become the new standard of care.

Phase I feasibility study of Olaparib in combination with loco-regional radiotherapy in head and neck squamous cell carcinoma

Purpose

PARP-inhibitors have potent radiosensitizing properties in pre-clinical models. To identify the maximum tolerated dose (MTD) of the PARP-inhibitor Olaparib in combination with radiotherapy in patients with head and neck cancer, a single institutional phase-I dose escalation trial was initiated.

Patients and methods

The starting dose of Olaparib was 25 mg BID, combined with radiotherapy (70 Gy in 35 fractions). The MTD was defined as the highest dose-level at which not more than 20 % of patients experience dose-limiting toxicities (DLT) or as the highest reached dose in the absence of DLT's.

Results

One week Olaparib-only treatment (25 mg QD) was administered to all patients prior to the start of radiotherapy. In dose-level I, Olaparib (25 mg BID) was combined with accelerated radiotherapy (70 Gy in 6 weeks). Because of DLT's in 3 of the 4 treated patients (acute tracheotomy 5 and 7 months and osteoradionecrosis 7 months after treatment), the Olaparib dose was de-escalated to 25 mg QD, and combined with conventional radiotherapy (70 Gy in 7 weeks) (dose-level II). There were no DLT's observed in 5 patients treated within dose-level II. After a median follow-up of 60 months, the 4-year LRC and OS rates were 77.8 % and 88.9 %, respectively.

Conclusion

Olaparib 25 mg QD combined with conventionally fractionated radiotherapy was well tolerated and identified as the MTD while severe DLT's were observed when Olaparib 25 mg BID was combined with accelerated radiation. This combination might be further explored in future Olaparib dose escalation studies in patients with locally-advanced HNSCC unfit for cisplatin-based chemoradiotherapy.

Adaptive FDG-PET/CT guided dose escalation in head and neck squamous cell carcinoma: Late toxicity and oncologic outcomes (The ADMIRE study)

Purpose

To report on the late toxicity and local control (LC) of head and neck cancer patients treated with adaptive FDG-PET/CT response-guided radiotherapy (ADMIRE) with dose escalation (NCT03376386).

Materials and methods

Between December 2017 and April 2019, 20 patients with stage II-IV squamous cell carcinoma of the larynx, hypopharynx or oropharynx were treated within the ADMIRE study where FDG-PET/CT response-guided (Week 2&4) dose escalation was applied (total dose 70-78 Gy). Cisplatin or cetuximab was added to radiotherapy in case of T3-4 and/or N2c disease. To compare the LC and late toxicity of the study population, we used an external control group (n = 67) consisting of all eligible patients for the study (but not participated). These patients were treated in our institution during the same period with the current standard of 70 Gy radiotherapy. To reduce the effect of confounding, logistic regression analyses was done using stabilized inverse probability of treatment weighting (SIPTW).

Results

After median follow-up of 40 and 43 months for the ADMIRE and control groups, the 3-year LC-rates were 74% and 78%, respectively (adjusted HR after SIPTW 0.80, 95 %CI 0.25-2.52, p = 0.70). The incidences of any late G3 toxicity were 35% and 18%, respectively. The adjusted OR for any late G3 toxicity was 5.09 (95 %CI 1.64-15.8, p = 0.005), for any late G ≥ 2 toxicity was 3.67 (95 %CI 1.2-11.7, p = 0.02), for persistent laryngeal edema was 10.95 (95% CI 2.71-44.29, p = 0.001), for persistent mucosal ulcers was 4.67 (95% CI 1.23-17.7, p = 0.023), and for late G3 radionecrosis was 15.69 (95 %CI 2.43-101.39, p = 0.004).

Conclusion

Given the comparable LC rates with increased late toxicity in the ADMIRE group, selection criteria for future adaptive dose escalation trials (preferably randomized) need to be refined to include only patients at higher risk of local failure and/or lower risk of severe late toxicity.

VoiceS: voice quality after transoral CO2 laser surgery versus single vocal cord irradiation for unilateral stage 0 and I glottic larynx cancer-a randomized phase III trial

Background

Surgery and radiotherapy are well-established standards of care for unilateral stage 0 and I early-stage glottic cancer (ESGC). Based on comparative studies and meta-analyses, functional and oncological outcomes after both treatment modalities are similar. Historically, radiotherapy (RT) has been performed by irradiation of the whole larynx. However, only the involved vocal cord is being treated with recently introduced hypofractionated concepts that result in 8 to 10-fold smaller target volumes. Retrospective data argues for an improvement in voice quality with non-inferior local control. Based on these findings, single vocal cord irradiation (SVCI) has been implemented as a routine approach in some institutions for ESGC in recent years. However, prospective data directly comparing SVCI with surgery is lacking. The aim of VoiceS is to fill this gap.

Methods

In this prospective randomized multi-center open-label phase III study with a superiority design, 34 patients with histopathologically confirmed, untreated, unilateral stage 0-I ESGC (unilateral cTis or cT1a) will be randomized to SVCI or transoral CO₂-laser microsurgical cordectomy (TLM). Average difference in voice quality, measured by using the voice handicap index (VHI) will be modeled over four time points (6, 12, 18, and 24 months). Primary endpoint of this study will be the patient-reported subjective voice quality between 6 to 24 months after randomization. Secondary endpoints will include perceptual impression of the voice via roughness – breathiness – hoarseness (RBH) assessment at the above-mentioned time points. Additionally, quantitative characteristics of voice, loco-regional tumor control at 2 and 5 years, and treatment toxicity at 2 and 5 years based on CTCAE v.5.0 will be reported.

Discussion

To our knowledge, VoiceS is the first randomized phase III trial comparing SVCI with TLM. Results of this study may lead to improved decision-making in the treatment of ESGC.

Trial registration

ClinicalTrials.gov NCT04057209. Registered on 15 August 2019. Cantonal Ethics Committee KEK-BE 2019-01506

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06841-5.

Largest diameter delineations can substitute 3D tumor volume delineations for radiomics prediction of human papillomavirus status on MRI's of oropharyngeal cancer

PURPOSE

Laborious and time-consuming tumor segmentations are one of the factors that impede adoption of radiomics in the clinical routine. This study investigates model performance using alternative tumor delineation strategies in models predictive of human papillomavirus (HPV) in oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

Of 153 OPSCC patients, HPV status was determined using p16/p53 immunohistochemistry. MR-based radiomic features were extracted within 3D delineations by an inexperienced observer, experienced radiologist or radiation oncologist, and within a 2D delineation of the largest axial tumor diameter and 3D spheres within the tumor. First, logistic regression prediction models were constructed and tested separately for each of these six delineation strategies. Secondly, the model trained on experienced delineations was tested using these delineation strategies. The latter methodology was repeated with the omission of shape features. Model performance was evaluated using area under the curve (AUC), sensitivity and specificity.

RESULTS

Models constructed and tested using single-slice delineations (AUC/Sensitivity/Specificity: 0.84/0.75/0.84) perform better compared to 3D experienced observer delineations (AUC/Sensitivity/Specificity: 0.76/0.76/0.71), where models based on 4 mm sphere delineations (AUC/Sensitivity/Specificity: 0.77/0.59/0.71) show similar performance. Similar performance was found when experienced and largest diameter delineations (AUC/Sens/Spec: 0.76/0.75/0.65 vs 0.76/0.69/0.69) was used to test the model constructed using experienced delineations without shape features.

CONCLUSION

Alternative delineations can substitute labor and time intensive full tumor delineations in a model that predicts HPV status in OPSCC. These faster delineations may improve adoption of radiomics in the clinical setting. Future research should evaluate whether these alternative delineations are valid in other radiomics models.

Strategies for tackling the class imbalance problem of oropharyngeal primary tumor segmentation on magnetic resonance imaging

•

Loss functions that account for class imbalance may not improve the segmentations.

•

Our two-stage segmentation approach can outperform the 3D U-Net.

•

A fully-automatic two-stage approach can perform comparably to a semi-automatic approach.

Background and purpose

Contouring oropharyngeal primary tumors in radiotherapy is currently done manually which is time-consuming. Autocontouring techniques based on deep learning methods are a desirable alternative, but these methods can render suboptimal results when the structure to segment is considerably smaller than the rest of the image. The purpose of this work was to investigate different strategies to tackle the class imbalance problem in this tumor site.

Materials and methods

A cohort of 230 oropharyngeal cancer patients treated between 2010 and 2018 was retrospectively collected. The following magnetic resonance imaging (MRI) sequences were available: T1-weighted, T2-weighted, 3D T1-weighted after gadolinium injection. Two strategies to tackle the class imbalance problem were studied: training with different loss functions (namely: Dice loss, Generalized Dice loss, Focal Tversky loss and Unified Focal loss) and implementing a two-stage approach (i.e. splitting the task in detection and segmentation). Segmentation performance was measured with Sørensen–Dice coefficient (Dice), 95th Hausdorff distance (HD) and Mean Surface Distance (MSD).

Results

The network trained with the Generalized Dice Loss yielded a median Dice of 0.54, median 95th HD of 10.6 mm and median MSD of 2.4 mm but no significant differences were observed among the different loss functions (p-value > 0.7). The two-stage approach resulted in a median Dice of 0.64, median HD of 8.7 mm and median MSD of 2.1 mm, significantly outperforming the end-to-end 3D U-Net (p-value < 0.05).

Conclusion

No significant differences were observed when training with different loss functions. The two-stage approach outperformed the end-to-end 3D U-Net.

Single vocal cord irradiation for early-stage glottic cancer: Excellent local control and favorable toxicity profile

OBJECTIVE

To validate the earlier reported promising oncologic outcomes and favorable toxicity profile following single vocal cord irradiation (SVCI) in an expanded cohort of patients with early-stage glottic cancer treated at our institute with longer follow-up time.

MATERIALS AND METHODS

Between February 2011 and January 2020, 111 consecutive patients with early-stage glottic cancer were treated with SVCI to the whole involved vocal cord (58.08 Gy, given in 16 fractions of 3.63 Gy). Setup verification was done using cone-beam CT, prior to each fraction. The endpoints were local control (LC), overall survival (OS), grade ≥ 3 toxicity and voice quality assessment using voice-handicap index (VHI) questionnaires.

RESULTS

Median follow-up was 41 months (range; 8-84). Two patients developed in-field local failure (LF). The 3- and 5-year LC rates were 99.1% and 97.1%, respectively. As both patients with LF were successfully salvaged with total laryngectomy, the 5-year ultimate LC-rates was 99%. The 5-years OS was 80.6%. All patients finished treatment without any interruption. No patients developed acute grade ≥ 3 toxicity. Late grade 3 toxicity was reported in 7 patients (6.5%) out of 108 patients evaluable for late toxicity; 2 because of severe hoarseness and 5 because of laryngeal radionecrosis (4.5%). The 5-years laryngectomy-free survival was 98.1%. The VHI-scores improved over time, only 22% of patients had VHI > 30 at 3-years post-radiotherapy, compared to 38% at baseline.

CONCLUSIONS

Local control rate and laryngectomy-free survival of SVCI are excellent with favorable toxicity profile and good VHI-score. These results validate our early results.

The dosimetric and clinical advantages of the GTV-CTV-PTV margins reduction by 6 mm in head and neck squamous cell carcinoma: Significant acute and late toxicity reduction

PURPOSE

We aim to identify the dosimetric and clinical impact of reducing the total GTV-CTV-PTV margins in head-and-neck squamous cell carcinoma (HNSCC) treated with definitive (chemo)radiation.

MATERIALS AND METHODS

The acute and late toxicity and outcomes of 155 consecutive patients treated between February 2017 and March 2019 with GTV-CTV-PTV margins of 9 mm were compared to those of 155 consecutive patients treated with total margin of 15 mm margin, before April 2015. All patients were treated with VMAT with daily-image guidance using CBCT.

RESULTS

Reducing the GTV-CTV-PTV by 6 mm resulted in significant reduction of total irradiated volume (PTV-total) by a median of 28.1% and significant reduction of doses to all salivary glands (largest reduction ipsilateral parotid gland; median -9.6 Gy) and constrictor muscle (-6.1 Gy) with subsequent reduction of the incidence of overall acute grade 3 toxicity (47.7% for 9 mm and 66.5% for 15 mm groups, p = 0.001), grade 3 mucositis (18.1% vs. 35.5%, p < 0.001) and feeding tube-dependency at the end of treatment (24.5% vs. 40%, p = 0.005). The incidence of late grade ≥ 2 xerostomia and dysphagia were also significantly lower in the 9 mm group (31.7% vs. 58.6% p < 0.001, and 15.4% vs. 26.7%, p = 0.04). The 2-year rates of loco-regional control, disease-free and overall survival were 78.8% vs.75.8%, 70.9% vs. 64.4%, and 83.8% vs. 67.6%, (p > 0.05, all).

CONCLUSION

Reduction of the total GTV-CTV-PTV margins from 15 to 9 mm in HNSCC significantly reduced the irradiated volumes and the dose to salivary glands and constrictor muscle with significant reduction of radiation-related toxicity. The loco-regional control rates of both groups were comparable.

[18F]FDG-PET accurately identifies pathological response early upon neoadjuvant immune checkpoint blockade in head and neck squamous cell carcinoma

Purpose

To investigate the utility of [¹⁸F]FDG-PET as an imaging biomarker for pathological response early upon neoadjuvant immune checkpoint blockade (ICB) in patients with head and neck squamous cell carcinoma (HNSCC) before surgery.

Methods

In the IMCISION trial (NCT03003637), 32 patients with stage II‒IVb HNSCC were treated with neoadjuvant nivolumab with (n = 26) or without (n = 6) ipilimumab (weeks 1 and 3) before surgery (week 5). [¹⁸F]FDG-PET/CT scans were acquired at baseline and shortly before surgery in 21 patients. Images were analysed for SUV_max, SUV_mean, metabolic tumour volume (MTV), and total lesion glycolysis (TLG). Major and partial pathological responses (MPR and PPR, respectively) to immunotherapy were identified based on the residual viable tumour in the resected primary tumour specimen (≤ 10% and 11–50%, respectively). Pathological response in lymph node metastases was assessed separately. Response for the 2 [¹⁸F]FDG-PET-analysable patients who did not undergo surgery was determined clinically and per MR-RECIST v.1.1. A patient with a primary tumour MPR, PPR, or primary tumour MR-RECIST-based response upon immunotherapy was called a responder.

Results

Median ΔSUV_max, ΔSUV_mean, ΔMTV, and ΔTLG decreased in the 8 responders and were significantly lower compared to the 13 non-responders (P = 0.05, P = 0.002, P < 0.001, and P < 0.001). A ΔMTV or ΔTLG of at least − 12.5% detected a primary tumour response with 95% accuracy, compared to 86% for the EORTC criteria. None of the patients with a ΔTLG of − 12.5% or more at the primary tumour site developed a relapse (median FU 23.0 months since surgery). Lymph node metastases with a PPR or MPR (5 metastases in 3 patients) showed a significant decrease in SUV_max (median − 3.1, P = 0.04). However, a SUV_max increase (median + 2.1) was observed in 27 lymph nodes (in 11 patients), while only 13 lymph nodes (48%) contained metastases in the corresponding neck dissection specimen.

Conclusions

Primary tumour response assessment using [¹⁸F]FDG-PET-based ΔMTV and ΔTLG accurately identifies pathological responses early upon neoadjuvant ICB in HNSCC, outperforming the EORTC criteria, although pseudoprogression is seen in neck lymph nodes. [¹⁸F]FDG-PET could, upon validation, select HNSCC patients for response-driven treatment adaptation in future trials.

Trial registration

https://www.clinicaltrials.gov/, NCT03003637, December 28, 2016.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-021-05610-x.

The association of pretreatment low skeletal muscle mass with chemotherapy dose-limiting toxicity in patients with head and neck cancer undergoing primary chemoradiotherapy with high-dose cisplatin

Background

Low skeletal muscle mass (SMM) is an adverse prognostic factor for chemotherapy dose‐limiting toxicity (CDLT). In patients with locally advanced head and neck squamous cell carcinoma (HNSCC) undergoing chemoradiotherapy (CRT), low SMM is a predictor for CDLT. We aimed to validate these findings.

Methods

Consecutive LA‐HNSCC patients treated with primary CRT with high‐dose cisplatin were retrospectively included. SMM was measured on pre‐treatment CT‐imaging. A cumulative cisplatin dose below 200 mg/m² was defined as CDLT.

Results

One hundred and fifty three patients were included; 37 (24.2%) experienced CDLT, and 84 had low SMM (54.9%). Patients with low SMM experienced more CDLT than patients with normal SMM (35.7% vs. 10.1%, p < 0.01). Low SMM (OR 3.99 [95% CI 1.56–10.23], p = 0.01) and an eGFR of 60–70 ml/min (OR 5.40 [95% CI 1.57–18.65], p < 0.01) were predictors for CDLT.

Conclusion

Pre‐treatment low SMM is associated with CDLT in LA‐HNSCC patients treated with primary CRT. Routine SMM assessment may allow for CDLT risk assessment and treatment optimization.

Comparisons of normal tissue complication probability models derived from planned and delivered dose for head and neck cancer patients

BACKGROUND AND PURPOSE

Normal tissue complication probability (NTCP) models are typically derived from the planned dose distribution, which can deviate from the delivered dose due to anatomical day-to-day variations. The aim of this study was to compare NTCP models derived from the planned and the delivered dose for head and neck cancer (HNC) patients.

MATERIAL AND METHOD

322 HNC patients who received radiotherapy with daily CBCT guidance were included in this retrospective study. The delivered dose was estimated by deformably accumulating dose from daily CBCT to planning anatomy. We used a Lyman-Kutcher-Burman NTCP model, to relate the equivalent uniform dose (EUD) of organs at risk (OAR) with oral mucositis, xerostomia and dysphagia respectively. We compared the model parameters and performances.

RESULTS

The median differences between planned and delivered EUD to the OARs were significantly larger for patients with toxicity than without for acute dysphagia (≥G2 and ≥G3) and late dysphagia (≥G3) (p < 0.05). Those differences resulted in small differences in steepness and agreement to the data between delivered- and planned-fitted NTCP curves, and the differences were not significant. The differences in AUC were less than 0.01.

CONCLUSION

Differences between delivered and planned dose did not lead to significant differences in NTCP curves. The additional clinical relevance of NTCP models using accumulated dose for oral mucositis, xerostomia and dysphagia in HNC radiotherapy is likely to be limited.

Radiotherapy as nose preservation treatment strategy for cancer of the nasal vestibule: The Dutch experience

BACKGROUND AND PURPOSE

Primary radiotherapy is often preferred for early-stage cancer of the nasal vestibule (CNV), combining high disease control with preservation of nasal anatomy. However, due to practice variation and an absence of comparative trials, no consensus exists on preference for brachytherapy (BT) or external beam radiotherapy (EBRT). We compared these modalities in terms of disease control, nose preservation rates and toxicity.

MATERIALS AND METHODS

Medical records of 225 patients with T1-T2 squamous cell carcinoma of the nasal vestibule treated with 3D image-guided primary radiotherapy between Jan 2010 and Dec 2016 in 6 Dutch institutions were reviewed retrospectively.

RESULTS

153 of 225 patients were treated with BT, 65 with EBRT and 7 with other modalities. Median follow-up was 46 months. Overall 3-year local control (LC) and regional control (RC) were 87% and 89%. Five-year disease-specific survival (DSS) and overall survival (OS) were 94% and 82%. Three-year survival with preserved nose (SPN) was 76%. BT provided higher 3-year LC (95% vs 71%, p < 0.01) and SPN compared with EBRT (82% vs 61%, p < 0.01). Multivariable and propensity-score-matched cohort analyses confirmed better outcomes after BT. No difference was seen in DSS or OS. Five-year incidence of CTCAE 5.0 grade ≥2 toxicity was higher after BT (20% vs 3%, p = 0.03) and consisted mostly of radiation ulcers. 50% of all late toxicity recovered.

CONCLUSION

In this largest-to-date multicenter analysis of T1-T2 CNV, BT achieved superior LC and SPN compared with EBRT. Grade 1-2 radiation ulcers occurred more frequently after brachytherapy, but were transient in half the cases. Considering these results, BT can be recommended as first-line treatment for T1-T2 CNV.

Deterioration of Intended Target Volume Radiation Dose Due to Anatomical Changes in Patients with Head-and-Neck Cancer

Delivered radiation dose can differ from intended dose. This study quantifies dose deterioration in targets, identifies predictive factors, and compares dosimetric to clinical patient selection for adaptive radiotherapy in head-and-neck cancer patients. One hundred and eighty-eight consecutive head-and-neck cancer patients treated up to 70 Gy were analyzed. Daily delivered dose was calculated, accumulated, and compared to the planned dose. Cutoff values (1 Gy/2 Gy) were used to assess plan deterioration in the highest/lowest dose percentile (D₁/D₉₉). Differences in clinical factors between patients with/without dosimetric deterioration were statistically tested. Dosimetric deterioration was evaluated in clinically selected patients for adaptive radiotherapy with CBCT. Respectively, 16% and 4% of patients had deterioration over 1 Gy in D₉₉ and D₁ in any of the targets, this was 5% (D₉₉) and 2% (D₁) over 2 Gy. Factors associated with deterioration of D₉₉ were higher baseline weight/BMI, weight gain early in treatment, and smaller PTV margins. The sensitivity of visual patient selection with CBCT was 22% for detection of dosimetric changes over 1 Gy. Large dose deteriorations in targets occur in a minority of patients. Clinical prediction based on patient characteristics or CBCT is challenging and dosimetric selection tools seem warranted to identify patients in need for ART, especially in treatment with small PTV margins.

Reduction of GTV to high-risk CTV radiation margin in head and neck squamous cell carcinoma significantly reduced acute and late radiation-related toxicity with comparable outcomes

BACKGROUND AND PURPOSE

We aim to retrospectively investigate whether reducing GTV to high-risk CTV margin will significantly reduce acute and late toxicity without jeopardizing outcome in head-and-neck squamous cell carcinoma (HNSCC) treated with definitive (chemo)radiation.

MATERIALS AND METHODS

Between April 2015 and April 2019, 155 consecutive patients were treated with GTV to high-risk CTV margin of 10 mm and subsequently another 155 patients with 6 mm margin. The CTV-PTV margin was 3 mm for both groups. All patients were treated with volumetric-modulated arc therapy with daily image-guidance using cone-beam CT. End points of the study were acute and late toxicity and oncologic outcomes.

RESULTS

Overall acute grade 3 toxicity was significantly lower in 6 mm, compared to 10 mm group (48% vs. 67%, respectively, p < 0.01). The same was true for acute grade 3 mucositis (18% vs. 34%, p < 0.01) and grade ≥ 2 dysphagia (67% vs. 85%, p < 0.01). Also feeding tube-dependency at the end of treatment (25% vs. 37%, p = 0.02), at 3 months (12% and 25%, p < 0.01), and at 6 months (6% and 15%, p = 0.01) was significantly less in 6 mm group. The incidence of late grade 2 xerostomia was also significantly lower in the 6 mm group (32% vs. 50%, p < 0.01). The 2-year rates of loco-regional control, disease-free and overall survival were 78.7% vs. 73.1%, 70.6% vs. 61.4%, and 83.2% vs. 74.4% (p > 0.05, all).

CONCLUSION

The first study reporting on reduction of GTV to high-risk CTV margin from 10 to 6 mm showed significant reduction of the incidence and severity of radiation-related toxicity without reducing local-regional control and survival.

Oropharyngeal primary tumor segmentation for radiotherapy planning on magnetic resonance imaging using deep learning

•

Reducing the context around the tumor results in better segmentations with CNNs.

•

Combining multiple MRI sequences as input can be beneficial to segmentation networks.

•

A semi-automatic approach is fast and can potentially improve the accuracy of segmentations.

Background and purpose

Segmentation of oropharyngeal squamous cell carcinoma (OPSCC) is needed for radiotherapy planning. We aimed to segment the primary tumor for OPSCC on MRI using convolutional neural networks (CNNs). We investigated the effect of multiple MRI sequences as input and we proposed a semi-automatic approach for tumor segmentation that is expected to save time in the clinic.

Materials and methods

We included 171 OPSCC patients retrospectively from 2010 until 2015. For all patients the following MRI sequences were available: T1-weighted, T2-weighted and 3D T1-weighted after gadolinium injection. We trained a 3D UNet using the entire images and images with reduced context, considering only information within clipboxes around the tumor. We compared the performance using different combinations of MRI sequences as input. Finally, a semi-automatic approach by two human observers defining clipboxes around the tumor was tested. Segmentation performance was measured with Sørensen–Dice coefficient (Dice), 95th Hausdorff distance (HD) and Mean Surface Distance (MSD).

Results

The 3D UNet trained with full context and all sequences as input yielded a median Dice of 0.55, HD of 8.7 mm and MSD of 2.7 mm. Combining all MRI sequences was better than using single sequences. The semi-automatic approach with all sequences as input yielded significantly better performance (p < 0.001): a median Dice of 0.74, HD of 4.6 mm and MSD of 1.2 mm.

Conclusion

Reducing the amount of context around the tumor and combining multiple MRI sequences improved the segmentation performance. A semi-automatic approach was accurate and clinically feasible.

Therapeutic neck dissection in head and neck melanoma patients: Comparing extent of surgery and clinical outcome in two cohorts

BACKGROUND

The extent of surgical management of regional lymph nodes in the treatment of cutaneous head and neck melanoma on and anterior to O'Brien's watershed line is controversial. By comparing patients' cohorts of two separate melanoma expert centers we investigate the effectiveness of comprehensive versus (super-) selective neck dissection approach.

METHODS

Sixty patients with macroscopic (palpable) neck node metastases (N2b) from anterior scalp and face melanoma were retrospectively studied. Forty therapeutic modified radical neck dissections (MRND; levels I-V) combined with elective parotidectomy from The Netherlands Cancer Institute (NCI) were compared with 16 (super-) selective neck dissections [(S)SND; 3-4 levels] and 4 solely MRNDs from Erasmus Medical Center (EMC). Cohorts were analyzed for site of recurrence, overall survival (OS), melanoma-specific survival (MSS), and disease-free survival (DFS).

RESULTS

Clinical characteristics of patients were equal in both groups. In the NCI cohort 62.5% (n = 25) of patients recurred versus 65% (n = 13) in the EMC cohort. None of the NCI recurrences affected the parotid gland in contrast to 3 patients in the EMC group. Survival characteristics were not different between the two groups: OS (p = 0.56), MSS (p = 0.98), DFS (p = 0.92).

CONCLUSION

This study does not support to continue the practice of routine elective parotidectomy and MRND in melanoma patients undergoing a lymph node dissection for macroscopic (palpable) nodal disease and justifies (S)SND.

Improved outcome prediction of oropharyngeal cancer by combining clinical and MRI features in machine learning models

OBJECTIVES

New markers are required to predict chemoradiation response in oropharyngeal squamous cell carcinoma (OPSCC) patients. This study evaluated the ability of magnetic resonance (MR) radiomics to predict locoregional control (LRC) and overall survival (OS) after chemoradiation and aimed to determine whether this has added value to traditional clinical outcome predictors.

METHODS

177 OPSCC patients were eligible for this study. Radiomic features were extracted from the primary tumor region in T1-weighted postcontrast MRI acquired before chemoradiation. Logistic regression models were created using either clinical variables (clinical model), radiomic features (radiomic model) or clinical and radiomic features combined (combined model) to predict LRC and OS 2-years posttreatment. Model performance was evaluated using area under the curve (AUC), 95 % confidence intervals were calculated using 500 iterations of bootstrap. All analyses were performed for the total population and the Human papillomavirus (HPV) negative tumor subgroup.

RESULTS

A combined model predicted treatment outcome with a higher AUC (LRC: 0.745 [0.734-0.757], OS: 0.744 [0.735-0.753]) than the clinical model (LRC: 0.607 [0.594-0.620], OS: 0.708 [0.697-0.719]). Performance of the radiomic model was comparable to the combined model for LRC (AUC: 0.740 [0.729-0.750]), but not for OS prediction (AUC: 0.654 [0.646-0.662]). In HPV negative patients, the performance of all models was not sufficient with AUCs ranging from 0.587 to 0.660 for LRC and 0.559 to 0.600 for OS prediction.

CONCLUSION

Predictive models that include clinical variables and radiomic tumor features derived from MR images of OPSCC better predict LRC after chemoradiation than models based on only clinical variables. Predictive models that include clinical variables perform better than models based on only radiomic features for the prediction of OS.

Muscarinic inhibition of salivary glands with glycopyrronium bromide does not reduce the uptake of PSMA-ligands or radioiodine

RATIONALE

Salivary glands are highly perfused and express the prostate-specific membrane antigen (PSMA) receptor as well as the sodium-iodide symporter. As a consequence, treatment with ¹⁷⁷Lu/²²⁵Ac-PSMA for prostate cancer or ¹³¹I for thyroid cancer leads to a high radiation dose in the salivary glands, and patients can be confronted with persistent xerostomia and reduced quality of life. Salivation can be inhibited using an antimuscarinic pharmaceutical, such as glycopyrronium bromide (GPB), which may also reduce perfusion. The primary objective of this work was to determine if inhibition with GPB could provide a considerable (> 30%) reduction in the accumulation of administered ¹²³I or ⁶⁸Ga-PSMA-11 in salivary glands.

METHODS

Ten patients who already received a whole-body ⁶⁸Ga-PSMA-11 PET/CT scan for (re)staging of prostate cancer underwent a repeat PET/CT scan with tracer administration at 90 min after intravenous injection of 0.2 mg GPB. Four patients in follow-up after thyroid cancer, who had been treated with one round of ablative ¹³¹I therapy with curative intent and had no signs of recurrence, received ¹²³I planar scintigraphy at 4 h after tracer administration without GPB and a repeated scan at least one week later, with tracer administration at 30 min after intramuscular injection of 0.4 mg GPB. Tracer uptake in the salivary glands was quantified on PET and scintigraphy, respectively, and values with and without GPB were compared.

RESULTS

No significant difference in PSMA uptake in the salivary glands was seen without or with GPB (Mean SUL_mean parotid glands control 5.57, intervention 5.72, p = 0.50. Mean SUL_mean submandibular glands control 6.25, intervention 5.89, p = 0.12). Three out of 4 patients showed increased ¹²³I uptake in the salivary glands after GPB (Mean counts per pixel control 8.60, intervention 11.46).

CONCLUSION

Muscarinic inhibition of salivation with GPB did not significantly reduce the uptake of PSMA-ligands or radioiodine in salivary glands, and can be dismissed as a potential strategy to reduce toxicity from radionuclide therapies.

Surgical site complications of post-chemoradiotherapy neck dissection: Urgent need for standard registration

Nowadays, a substantial number of head and neck cancer patients are treated by organ-preserving chemoradiation (CRT), with a possible increased risk of complications after planned or salvage neck dissections. We try to determine the risk pattern of surgical site complications (SSC) post-CRT.

Randomized controlled trial to identify the optimal radiotherapy scheme for palliative treatment of incurable head and neck squamous cell carcinoma

BACKGROUND

No randomized controlled trials (RCT) have yet identified the optimal palliative radiotherapy scheme in patients with incurable head and neck squamous cell carcinoma (HNSCC). We conducted RCT to compare two radiation schemes in terms of efficacy, toxicity and quality-of-life (QoL).

MATERIALS AND METHODS

Patients with locally-advanced HNSCC who were ineligible for radical treatment and those with limited metastatic disease were randomly assigned in 1:1 ratio to arm 1 (36 Gy in 6 fractions, twice a week) or arm 2 (50 Gy in 16 fractions, four times a week).

RESULTS

The trial was discontinued early because of slow accrual (34 patients enrolled). Objective response rates were 38.9% and 57.1% for arm 1 and 2 respectively (p = 0.476). The median time to loco-regional progression was not reached. The loco-regional control rates at 1 year was 57.4% and 69.3% in arm 1 and 2 (p = 0.450, HR = 0.56, 95%CI 0.12-2.58). One-year overall survival was 33.3% and 57.1%, with medians of 35.4 and 59.5 weeks, respectively (p = 0.215, HR = 0.55, 95%CI 0.21-1.43). Acute grade ≥3 toxicity was lower in arm 1 (16.7% versus 57.1%, p = 0.027), with the largest difference in grade 3 mucositis (5.6% versus 42.9%, p = 0.027). However, no significant deterioration in any of the patient-reported QoL-scales was found.

CONCLUSION

No solid conclusion could be made on this incomplete study which is closed early. Long-course radiotherapy did not show significantly better oncologic outcomes, but was associated with more acute grade 3 mucositis. No meaningful differences in QoL-scores were found. Therefore, the shorter schedule might be carefully advocated. However, this recommendation should be interpreted with great caution because of the inadequate statistical power.

Protocolised way to cope with anatomical changes in head & neck cancer during the course of radiotherapy

INTRODUCTION

During a course of radiotherapy for head-and-neck-cancer (HNC), non-rigid anatomical changes can be observed on daily Cone Beam CT (CBCT). To objectify responses to these changes, we use a decision support system (traffic light protocol). Action levels orange and red may lead to re-planning. The purpose of this study was to evaluate how often re-planning was done for non-rigid anatomical changes, which anatomical changes led to re-planning and in which subgroups of patients treatment adaptation was deemed necessary.

MATERIALS AND METHODS

A consecutive series of 388 HNC patients were retrospectively selected using the digital log of CBCT scans. The logs were analyzed for the number of new plans on an original planning CT scan (O-pCT) or a new pCT scan (N-pCT). Reasons for re-planning were categorized into: target volume increase/decrease, body contour decrease/increase and local shift of target volume. Subgroup analysis was performed to investigate relative differences of re-planning between treatment modalities.

RESULTS

For 33 patients the treatment plan was adapted due to anatomical changes, resulting in 37 new plans in total. Re-planning on a N-pCT with complete re-delineation was done 22 times. In fifteen cases a new plan was created after adjustment of contours on the O-pCT. Main reasons for re-planning were target volume increase, body contour decrease and local shifts of target volume. Most re-planning (23%) was seen in patients treated with chemoradiotherapy.

CONCLUSION

Visual detection of anatomical changes on CBCT during treatment of HNC, results in re-planning in 1 out of 10 patients.

Mapping of sentinel lymph node drainage using SPECT/CT to tailor elective nodal irradiation in head and neck cancer patients (SUSPECT-2): a single-center prospective trial

Background

The majority of patients with head and neck squamous cell carcinoma (HNSCC) receive bilateral elective nodal irradiation (ENI), in order to reduce the risk of regional failure. Bilateral ENI, as compared to unilateral ENI, is associated with higher incidence of acute and late radiation-induced toxicity with subsequent deterioration of quality of life. Increasing evidence that the incidence of contralateral regional failure (cRF) in lateralized HNSCC is very low (< 10%) suggests that it can be justified to treat selected patients unilaterally. This trial aims to minimize the proportion of patients that undergo bilateral ENI, by using lymph drainage mapping by SPECT/CT to select patients with a minimal risk of contralateral nodal failure for unilateral elective nodal irradiation.

Methods

In this one-armed, single-center prospective trial, patients with primary T1-4 N0-2b HNSCC of the oral cavity, oropharynx, larynx (except T1 glottic) or hypopharynx, not extending beyond the midline and planned for primary (chemo) radiotherapy, are eligible. After ^99mTc-nanocolloid tracer injection in and around the tumor, lymphatic drainage is visualized using SPECT/CT. In case of contralateral lymph drainage, a contralateral sentinel node procedure is performed on the same day. Patients without contralateral lymph drainage, and patients with contralateral drainage but without pathologic involvement of any removed contralateral sentinel nodes, receive unilateral ENI. Only when tumor cells are found in a contralateral sentinel node the patient will be treated with bilateral ENI. The primary endpoint is cumulative incidence of cRF at 1 and 2 years after treatment. Secondary endpoints are radiation-related toxicity and quality of life. The removed lymph nodes will be studied to determine the prevalence of occult metastatic disease in contralateral sentinel nodes.

Discussion

This single-center prospective trial aims to reduce the incidence and duration of radiation-related toxicities and improve quality of life of HNSCC patients, by using lymph drainage mapping by SPECT/CT to select patients with a minimal risk of contralateral nodal failure for unilateral elective nodal irradiation.

Trial registration

ClinicalTrials.gov Identifier: NCT03968679, date of registration: May 30, 2019.

Feasibility and toxicity of neoadjuvant nivolumab with or without ipilimumab prior to extensive (salvage) surgery in patients with advanced head and neck cancer (the IMCISION trial, NCT03003637)

2575

Background: surgery w/wo adjuvant radiotherapy (RT) for (recurrent) advanced head and neck squamous cell carcinoma (HNSCC) results in 30-50% 5-year OS, indicating the need for novel treatment options. In recurrent metastatic HNSCC nivolumab nearly tripled the 2-year OS. Aiming at improving clinical outcome in advanced HNSCC in a curative setting, we tested the feasibility of nivolumab ± ipilimumab neoadjuvant to (salvage) surgery w/wo RT. Methods: investigator-initiated phase-IB/II trial to assess feasibility of neoadjuvant nivolumab monotherapy (240 mg in week 1&3: arm-A) or in combination with ipilimumab (1 mg/kg in week 1: arm-B) before surgery (≤ week 5) w/wo RT for advanced HNSCC. Results: 12 patients were included (3+3 design, both arms) in phase-IB of this study; 7/12 (58%) patients had pre-existent moderate-to-severe comorbidities (ACE-27). All patients were HPV negative. All patients received surgery as planned (25-33 days after start of immunotherapy) with no unexpected wound healing problems. In both groups, 4 patients (67%) experienced immune-related toxicity: grade 1-2 (n = 4) and grade 3-4 (n = 1; colitis) in arm-A; grade 1-2 (n = 5) and grade 3-4 (n = 2; colitis and elevated liver enzymes) in arm B. Immune-related toxicity was managed with prednisone (n = 2) and infliximab (n = 1). There was 1/6 (12.5%) pathological response in arm-A (1 near complete response, nCR) and 3/6 (50%) in arm-B (1x partial response and 2x nCR). No patients with nCR had a recurrence at follow-up (median 10 months). Preliminary data (mutational load will be added) show increased H7-B3 gene expression in non-responders before treatment, and increased endothelial cell and NK cell gene expression in responders post-treatment. Overall, in these 12 patients, neoadjuvant ipilimumab + nivolumab resulted in a significant increase in immune-related gene expression when compared to nivolumab only, irrespective of treatment response. Conclusions: neoadjuvant ipilimumab + nivolumab can safely be administered prior to major surgery for advanced HNSCC. Efficacy is promising and will be further evaluated in the phase-II trial continuation. Clinical trial information: NCT03003637.

Organ Function Preservation Failure after (Chemo)Radiotherapy in Head and Neck Cancer: A Retrospective Cohort Analysis

Objective

The aim of the current study was to determine the incidence of organ function preservation failure (OFPF) in patients with head and neck squamous cell carcinoma (HNSCC) treated by (chemo)radiotherapy and to identify its risk factors.

Study Design

Retrospective cohort analysis.

Setting

Tertiary cancer care center.

Subjects and Methods

A single-center retrospective cohort analysis was done (n = 703) in which OFPF after (chemo)radiotherapy was assessed. OFPF was defined as local failure or pure functional failure in the absence of local failure because of major surgical intervention (total laryngectomy, commando resection, permanent tracheostomy) or feeding tube dependence >2 years.

Results

OFPF occurred in 153 patients (21.8%). Reasons for OFPF were local failure in 103 patients (14.6%) and functional failure in 50 patients (7.2%). Evidence of functional failure included need for total laryngectomy (n = 9, 1.3%), commando resection (n = 2, 0.3%), permanent tracheostomy (n = 16, 2.3%), and/or long-term feeding tube for functional reasons (n = 23, 3.3%). In a Cox proportional hazards model, OFPF was worse for patients with T4 tumors (hazard ratio [HR] <0.5 and P < .001 for all other stages), for laryngeal vs oropharyngeal cancer (HR, 1.83; 95% confidence interval [CI], 1.20-2.79, P = .005, hypopharyngeal not significant), and for smokers (HR, 1.68; 95% CI, 1.10-2.56, P = .015). Exploratory multivariate analysis by tumor site showed that T4 tumor and pretreatment tracheostomy were the strongest predictive factors for OFPF in laryngeal and hypopharyngeal carcinoma while T4 tumor and smoking were predictive for poor OFPF in oropharyngeal carcinoma.

Conclusion

This work shows a detrimental effect of smoking on functional outcomes after (chemo-)radiotherapy for HNSCC. Moreover, T4 tumor, laryngeal subsite, and pretreatment tracheostomy are strong predictors of OFPF.

Incidence of contralateral regional failure in the electively irradiated contralateral neck of patients with head and neck squamous cell carcinoma

•

Contralateral regional failure still occurs after bilateral nodal irradiation.

•

No significant predictive factors were identified for contralateral regional failure.

•

Overall survival did not differ between patients with ipsi- or contralateral failure.

Background

The vast majority of patients with head and neck squamous cell carcinoma (HNSCC) routinely undergo elective nodal irradiation (ENI) to both sides of the neck. Little is known about the extent to which bilateral ENI prevents regional failure (RF) and contralateral RF (cRF) in particular, while such knowledge is necessary to evaluate the results of more selective approaches like unilateral ENI. We investigated the rate and pattern of RF after bilateral ENI, the rate of cRF in the electively irradiated contralateral neck, and tried to identify risk factors for development of cRF.

Materials and methods

Retrospective cohort study of a consecutive series of 605 patients with T1-4N0-3 HNSCC treated between 2008 and 2017 with primary (chemo)radiation and bilateral ENI.

Results

Median follow-up was 43 months (range 1.4–126). Three-year cumulative incidence of RF was 12.7%. Three-year cumulative incidences of ipsilateral RF (iRF) and cRF were 10.6% and 2.8%, respectively. All cRF occurred within the electively treated volume. Salvage treatment was possible in 65% and 59% of patients with iRF and cRF, respectively (p = 0.746). The 3-year overall survival rates after RF in patients with iRF and cRF were 27.4% and 41.2%, respectively (p = 0.713). Three-year cancer-specific survival rates were 31.6% and 48.1%, respectively (p = 0.634). In multivariate analysis, no significant predictive factors were identified for cRF after bilateral ENI.

Conclusion

Contralateral regional failure is rare, but still occurs in 2.8% of patients treated with bilateral ENI. The possibilities for salvage treatment, the rates of overall survival and cancer-specific survival were comparable to patients with iRF.

Prostate-specific membrane antigen positron emission tomography/computed tomography as a potential tool to assess and guide salivary gland irradiation

•

PSMA PET/CT allows visualisation of salivary glands with good spatial and contrast resolution.

•

Evaluable glands include minor and less well-known gland locations.

•

PSMA PET/CT can visualise damage to salivary glands from external beam radiotherapy.

•

PSMA PET/CT has the potential to guide optimisation of radiotherapy to the head and neck.

•

The potential benefit of PSMA PET/CT is to avoid salivary gland toxicity and preserve quality of life.

Evaluation of salivary gland damage after head and neck radiotherapy (RT) is difficult with current tools, such as subjective patient-reported outcome measures. We demonstrate the use of prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) as an objective non-invasive tool to visualize damage to salivary glands resulting from RT. In three clinical cases, the PSMA-ligand distribution correlates to the RT dose distribution including intra-gland dose gradients and matches patient-reported toxicity, suggesting a dose-response relation. These findings support further exploration of PSMA PET/CT to guide and evaluate RT, with the ultimate aim to reduce salivary gland toxicity.

FDG-PET/CT improves detection of residual disease and reduces the need for examination under anaesthesia in oropharyngeal cancer patients treated with (chemo-)radiation

PURPOSE

Early detection of residual disease (RD) after (chemo)radiation for oropharyngeal (OPC) is crucial. Surveillance of neck nodes with FDG-PET/CT has been studied extensively, whereas its value for local RD remains less clear. We aim to evaluate the diagnostic value of post-treatment FDG-PET/CT in detecting local RD and the outcome of patients with local RD.

METHODS

A cohort (n = 352) of consecutively treated OPC patients at our institute between 2010 and 2017 was evaluated. Patients that underwent FDG-PET/CT at 3 months post-treatment (n = 94) were classified as having complete (CMR) or partial metabolic response (PMR). PMR was defined as visually detectable metabolic activity above the background of surrounding normal tissues. Primary endpoint was diagnostic accuracy in detecting local RD.

RESULTS

Local RD was seen in 19/352 patients (5%), all of them were HPV negative. The FDG-PET/CT had a sensitivity of 100% (8/8), specificity 85% (73/86), PPV 38% (8/21), NPV 100% (73/73), and accuracy 86%. Patients with local RD had significantly worse OS at 2 years, compared to those without (10 versus 88%, P < 0.001). In multivariable analysis, local RD remained a significant predictive factor for death with a hazard ratio of 11.9 (95% CI 5.8-24.3). The number of patients that underwent PET/CT increased over time (P < 0.001), whereas the number of patients that underwent EUA declined (P = 0.072).

CONCLUSION

FDG-PET/CT has excellent performance for the detection of RD, with the sensitivity and negative predictive value approaching 100%. Due to these excellent results is examination under anaesthesia today in the vast majority of the PET-negative cases not necessary anymore.

Salvage surgery for advanced stage head and neck squamous cell carcinoma following radiotherapy or chemoradiation

PURPOSE

Salvage surgery for recurrent advanced stage head and neck squamous cell carcinoma (HNSCC) is known to result in poor prognosis. As there are only small and heterogeneous studies available with wide variety in outcome measures, our purpose was to select and pool literature according to specific criteria.

METHODS

Systematic review and meta-analysis of clinical outcome after salvage surgery for recurrent advanced stage HNSCC following primary radiotherapy or chemoradiation.

RESULTS

16 of 3956 screened studies were included for analysis (729 patients). Pooled 5-year OS was 37% (95% CI 30-45%, 12 studies, 17 outcome measurements, 540 patients). Outcome was presented for larynx (6 studies, 397 patients), hypopharynx (2 studies, 47 patients), larynx and hypopharynx combined (3 studies, 69 patients) or separately (1 study, 134 patients), oral cavity (1 study, 11 patients), oropharynx (1 study, 34 patients) and multiple subsites combined (2 studies, 37 patients). There was no significant difference in survival outcome between subsites (p_{heterogeneity} = 0.8116). The pooled tumor-positive resection margin rate was 32% and pooled re-operation rate 17%. Complication rates from the pooled data were: fistulas 33%, wound infections 24% and flap failure 3%. Treatment-related mortality rate was 1% and mean hospital stay was 23 days.

CONCLUSIONS

Salvage surgery for recurrent advanced stage head and neck squamous cell carcinoma after primary (chemo)radiotherapy is a good last resort curative treatment option, resulting in 37% overall survival at 5 years. As data from advanced stage non-laryngeal tumors were sparse, no solid conclusions can be drawn with regard to outcome differences between tumor subsites.

Salvage Surgery for Recurrence after Radiotherapy for Squamous Cell Carcinoma of the Head and Neck

OBJECTIVE

Most studies that report on salvage surgery after primary radiotherapy for head and neck squamous cell carcinoma (HNSCC) are small and heterogeneous. Subsequently, some relevant questions remain unanswered. We specifically focused on (1) difference in prognosis per tumor subsite, corrected for disease stage, and (2) differences in prognosis after salvage surgery for local, regional, and locoregional recurrences.

STUDY DESIGN

Retrospective analysis.

SETTING

Single-center study (2000-2016).

SUBJECTS AND METHODS

Patients treated with salvage surgery for HNSCC recurrence after (chemo)radiotherapy.

RESULTS

In total, 189 patients were included. Five-year overall survival (OS) was 33%, and median OS was 18 (95% confidence interval [CI], 11-26) months. Treatment-related mortality was 2%. Larynx carcinoma was associated with more favorable local (adjusted hazard ratio [HR] = 4.02; 95% CI, 1.46-11.10; P = .007) and locoregional control (adjusted HR = 5.34; 95% CI, 1.83-15.61; P = .002) than pharyngeal carcinoma. American Society of Anesthesiologists (ASA) score (≥3 vs 1-2: adjusted HR = 3.04; 95% CI, 1.17-7.91; P = .023), pT stage (3-4 vs 1-2: adjusted HR = 4.41; 95% CI, 1.65-11.82; P = .003), and salvage surgery for locoregional recurrences (locoregional vs local: adjusted HR = 3.81; 95% CI, 1.13-11.82; P = .021) were independent predictors for disease-free survival (DFS).

CONCLUSION

Salvage surgery for larynx carcinoma, regardless of disease stage and other prognostic factors, results in more favorable loco(regional) control but not favorable DFS than pharyngeal carcinoma. The observed difference in DFS between salvage surgery for local and regional recurrences was not significant after correction for confounders. However, survival following salvage surgery for locoregional disease is significantly worse. For this subgroup, we propose to consider T status and comorbidity for clinical decision making, as high pT stage and ASA score are independent predictors for worse DFS.

Magnetic Resonance-based Response Assessment and Dose Adaptation in Human Papilloma Virus Positive Tumors of the Oropharynx treated with Radiotherapy (MR-ADAPTOR): An R-IDEAL stage 2a-2b/Bayesian phase II trial

BACKGROUND

Current standard radiotherapy for oropharynx cancer (OPC) is associated with high rates of severe toxicities, shown to adversely impact patients' quality of life. Given excellent outcomes of human papilloma virus (HPV)-associated OPC and long-term survival of these typically young patients, treatment de-intensification aimed at improving survivorship while maintaining excellent disease control is now a central concern. The recent implementation of magnetic resonance image - guided radiotherapy (MRgRT) systems allows for individual tumor response assessment during treatment and offers possibility of personalized dose-reduction. In this 2-stage Bayesian phase II study, we propose to examine weekly radiotherapy dose-adaptation based on magnetic resonance imaging (MRI) evaluated tumor response. Individual patient's plan will be designed to optimize dose reduction to organs at risk and minimize locoregional failure probability based on serial MRI during RT. Our primary aim is to assess the non-inferiority of MRgRT dose adaptation for patients with low risk HPV-associated OPC compared to historical control, as measured by Bayesian posterior probability of locoregional control (LRC).

METHODS

Patients with T1-2 N0-2b (as per AJCC 7th Edition) HPV-positive OPC, with lymph node <3 cm and <10 pack-year smoking history planned for curative radiotherapy alone to a dose of 70 Gy in 33 fractions will be eligible. All patients will undergo pre-treatment MRI and at least weekly intra-treatment MRI. Patients undergoing MRgRT will have weekly adaptation of high dose planning target volume based on gross tumor volume response. The stage 1 of this study will enroll 15 patients to MRgRT dose adaptation. If LRC at 6 months with MRgRT dose adaptation is found sufficiently safe as per the Bayesian model, stage 2 of the protocol will expand enrollment to an additional 60 patients, randomized to either MRgRT or standard IMRT.

DISCUSSION

Multiple methods for safe treatment de-escalation in patients with HPV-positive OPC are currently being studied. By leveraging the ability of advanced MRI techniques to visualize tumor and soft tissues through the course of treatment, this protocol proposes a workflow for safe personalized radiation dose-reduction in good responders with radiosensitive tumors, while ensuring tumoricidal dose to more radioresistant tumors. MRgRT dose adaptation could translate in reduced long term radiation toxicities and improved survivorship while maintaining excellent LRC outcomes in favorable OPC.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03224000; Registration date: 07/21/2017.