Comparative effectiveness of simultaneous integrated boost vs sequential intensity-modulated radiotherapy for oropharyngeal or hypopharyngeal cancer patients: A population-based propensity score-matched analysis

Detailed analysis of failure patterns using deformable image registration in hypopharyngeal cancer patients treated with sequential boost intensity-modulated radiotherapy

INTRODUCTION

Sequential boost intensity-modulated radiotherapy (SQB-IMRT) uses two different planning CTs (pCTs) and treatment plans. SQB-IMRT is a form of adaptive radiotherapy that allows for responses to changes in the shape of the tumour and organs at risk (OAR). On the other hand, dose accumulation with the two plans can be difficult to evaluate. The purpose of this study was to analyse patterns of loco-regional failure using deformable image registration (DIR) in hypopharyngeal cancer patients treated with SQB-IMRT.

METHODS

Between 2013 and 2019, 102 patients with hypopharyngeal cancer were treated with definitive SQB-IMRT at our institution. Dose accumulation with the 1st and 2nd plans was performed, and the dose to the loco-regional recurrent tumour volume was calculated using the DIR workflow. Failure was classified as follows: (i) in-field (≥95% of the recurrent tumour volume received 95% of the prescribed dose); (ii) marginal (20-95%); or (iii) out-of-field (<20%).

RESULTS

After a median follow-up period of 25 months, loco-regional failure occurred in 34 patients. Dose-volume histogram analysis showed that all loco-regional failures occurred in the field within 95% of the prescribed dose, with no marginal or out-of-field recurrences observed.

CONCLUSION

The dosimetric analysis using DIR showed that all loco-regional failures were within the high-dose region. More aggressive treatment may be required for gross tumours.

Matched-pair analysis of survival in patients with poorly differentiated versus well and moderately differentiated hypopharyngeal squamous cell carcinoma

Hypopharyngeal squamous cell carcinoma (HPSCC) is among the most common malignances of the head and neck and is associated with a poor prognosis. Although both differentiation and tumor-node-metastasis stage affect tumor aggressiveness, the effect of differentiation on the prognosis of HPSCC at different stages is unclear. The aim of this study was to compare survival outcomes between patients with poorly differentiated versus well-differentiated and moderately differentiated HPSCC. Patients with well/moderately differentiated and poorly differentiated HPSCC were matched based on age, sex, smoking status, alcohol use, comorbidity score, tumor stage, and therapeutic strategies. The Kaplan-Meier curve and Cox proportional hazards model were used to analyze survival. A total of 204 patients with newly diagnosed HPSCC were included after matching 102 well/moderately differentiated cases and 102 poorly differentiated cases from Peking Union Medical College Hospital. Patients with well/moderately differentiated HPSCC had significantly better disease-specific survival (P = .003) and overall survival (P = .006) than patients with poorly differentiated HPSCC. Additionally, multivariable analysis indicated that increased differentiation was associated with a significantly reduced risk of overall death (adjusted hazard ratio, 0.51; 95% confidence interval, 0.34-0.78, P = .002), and death due to disease (adjusted hazard ratio, 0.44; 95% confidence interval, 0.28-0.69, P < .001). Survival outcomes differed significantly between the well/moderately differentiated and poorly differentiated HPSCC patients. Treatment strategies based on the level of pathological differentiation might be necessary to improve survival outcomes in patients with HPSCC.

A randomized prospective study comparing acute toxicity, compliance and objective response rate between simultaneous integrated boost and sequential intensity-modulated radiotherapy for locally advanced head and neck cancer

PURPOSE

Intensity-modulated radiotherapy (IMRT) provides higher dose to target volumes and limits the dose to normal tissues. IMRT may be applied using either simultaneous integrated boost (SIB-IMRT) or sequential boost (SEQ-IMRT) technique. The objectives of this study were to compare acute toxicity and objective response rates between SIB-IMRT and SEQ-IMRT in patients with locally advanced head and neck cancer.

MATERIALS AND METHODS

Total 110 patients with locally advanced carcinoma of oropharynx, hypopharynx, and larynx were randomized equally into the two arms (SIB-IMRT vs. SEQ-IMRT). Patients in SIB-IMRT arm received dose of 66 Gy in 30 fractions, 5 days a week, over 6 weeks. SEQ-IMRT arm's patients received 70 Gy in 35 fractions over 7 weeks. Weekly concurrent cisplatin chemotherapy was given in both arms. Patients were assessed for acute toxicities during the treatment and for objective response at 3 months after the radiotherapy.

RESULTS

Grade 3 dysphagia was significantly more with SIB-IMRT compared to SEQ-IMRT (72% vs. 41.2%; p = 0.006) but other toxicities including mucositis, dermatitis, xerostomia, weight-loss, incidence of nasogastric tube intubation and hospitalization for supportive management were similar in both the arms. Patients in SIB-IMRT arm showed better treatment-compliance and had significantly less treatment-interruption compared to SEQ-IMRT arm (p = 0.028). Objective response rates were similar in both the arms (p = 0.783).

CONCLUSION

Concurrent chemoradiation with SIB-IMRT for locally advanced head and neck cancer is well-tolerated and results in better treatment-compliance, similar objective response rates, comparable incidence of mucositis and higher incidence of grade 3 dysphagia compared to SEQ-IMRT.

Moderately accelerated intensity-modulated radiation therapy using simultaneous integrated boost: Practical reasons or evidence-based choice? A critical appraisal of literature

Concurrent chemo-radiotherapy is the non-surgical mainstay of treatment for locally advanced head and neck squamous cell carcinoma (HNSCC). The following aspects have emerged as fundamental components of the combined approach: first, intensity modulated radiotherapy (IMRT) is the minimum standard technical requirement, with level 1 evidence in support of its reduction of late treatment-induced morbidity in comparison with 3D conformal radiotherapy. Second, cisplatin-based chemotherapy is the preferred systemic agent to be associated with radiation, with 100 mg/m² every 3 weeks deemed as the reference schedule. Because of significant progress in irradiation techniques achieved in last 15 years, the optimal fractionation schedule in modern radiation era remains controversial, especially for locally advanced disease. The purpose of this work was to perform a critical review on the value of moderately accelerated IMRT using simultaneous-integrated boost (SIB) in HNSCC, aiming to provide insights on current clinical practice and directions for future research.