Is there a patient population with squamous cell carcinoma of the head and neck region who might benefit from de-intensification of postoperative radiotherapy? : A monocentric retrospective analysis of a previously defined low-risk patient population treated with standard-of-care radiotherapy

Less is more: Exploring neoadjuvant immunotherapy as a de-escalation strategy in head and neck squamous cell carcinoma treatment

Head and neck squamous cell carcinoma (HNSCC) constitutes a significant global cancer burden, given its high prevalence and associated mortality. Despite substantial progress in survival rates due to the enhanced multidisciplinary approach to treatment, these methods often lead to severe tissue damage, compromised function, and potential toxicity. Thus, there is an imperative need for novel, effective, and minimally damaging treatment modalities. Neoadjuvant treatment, an emerging therapeutic strategy, is designed to reduce tumor size and curtail distant metastasis prior to definitive intervention. Currently, neoadjuvant chemotherapy (NACT) has optimized the treatment approach for a subset of HNSCC patients, yet it has not produced a noticeable enhancement in overall survival (OS). In the contemporary cancer therapeutics landscape, immunotherapy is gaining traction at an accelerated pace. Notably, neoadjuvant immunotherapy (NAIT) has shown promising radiological and pathological responses, coupled with encouraging efficacy in several clinical trials. This potentially paves the way for a myriad of possibilities in treatment de-escalation of HNSCC, which warrants further exploration. This paper reviews the existing strategies and efficacies of neoadjuvant immune checkpoint inhibitors (ICIs), along with potential de-escalation strategies. Furthermore, the challenges encountered in the context of the de-escalation strategies of NAIT are explored. The aim is to inform future research directions that strive to improve the quality of life (QoL) for patients battling HNSCC.

De-intensification of postoperative radiotherapy in head and neck cancer irrespective of human papillomavirus status-results of a prospective multicenter phase II trial (DIREKHT Trial)

Background

Current standard treatment concepts in head and neck squamous cell carcinoma (HNSCC) are based on former studies using 2D and 3D treatment plans. However, modern radiation techniques allow for a more precise and individual dose application. Therefore, in a clearly defined patient population, de-intensified risk-adapted radiation is investigated.

Methods

Patients with newly diagnosed HNSCC after surgery (with resection margins ≥1 mm and cM0) with the following tumor stages (TNM 7th Edition) were eligible for the study: oral cavity, oropharynx, or larynx: pT1-3, pN0-pN2b; hypopharynx: pT1-2, pN1. The patients should have either a low risk of local recurrence [≤pT2, resection margin ≥5 mm, no peritumoral lymphangiosis (L0), and no perineural invasion] or contralateral lymph node metastasis (≤3 ipsilateral lymph node metastases, in case of well-lateralized oropharyngeal or oral cavity cancer contralateral cN0, otherwise pN0). Patients were assigned to three different treatment regimes with reduction of the treated volume, radiation dose, or both, according to tumor stage and results of surgery performed. The primary objective was to show an LRR of <10% after 2 years.

Findings

A total of 150 patients were enrolled. Tumor localizations were as follows: n = 53 (35.3%), oral cavity; n = 94 (62.7%), oropharynx (82% HPV-positive); n = 2 (1.3%), hypopharynx; and n = 1 (0.7%), larynx. A total of 61 patients (41.0%) were stage IVA, 81 (54.0%) were stage III, and 8 (5.3%) were stage II. Median follow-up was 36 months. Cumulative incidence of 2y-LRR was 5.6% (95% CI: 1.7%-9.2%) in the whole study population and 14.1% (95% CI: 3.8%-23.2%) in patients with oral cavity cancer. Cumulative incidence of 2y-LRR in non-irradiated or dose-reduced regions was 3.5% (95% CI: 0.4%-6.5%). After 2 years, disease-free survival was 92% (95% CI: 87%-96%) and overall survival was 94% (95% CI: 90%-98%) for the complete study cohort. Acute III° toxicity was as follows: dysphagia, 30%; xerostomia, 7%; mucositis, 19%; and dermatitis, 4%. Dysphagia and xerostomia decrease over time. After 27 months, late dysphagia III° and xerostomia II° were 1% and 9%, respectively.

Interpretation

The study met its primary objective. De-intensification of postoperative radiotherapy irrespective of HPV status in a predefined patient population is associated with a favorable toxicity profile without compromising LRR. In an unplanned subgroup analysis, a significantly increased risk of LRR was observed in patients with oral cavity cancer. In these patients, de-intensified radiotherapy should be applied with caution.

Postoperative radiotherapy may not be necessary for locally advanced head and neck squamous cell carcinoma: a case-match multicentre study

Background

Some head and neck cancer surgeons found that many patients with locally advanced head and neck squamous cell carcinoma (LA-HNSCC) without postoperative radiotherapy (PORT) also have a good prognosis. The purpose of this study was to determine the effect of PORT on survival in patients with LA-HNSCC.

Methods

A case-match cohort analysis was performed at two institutions on patients with LA-HNSCC. Patients who received surgery alone were case-matched 1: 1 with patients treated by surgery plus PORT based on pT, pN, tumor subsite etc.

Results

114 patients were matched into 57 pairs, with a median follow-up period of 40.2 months. No difference in overall survival (OS, HR 0.88; 95% CI 0.50–1.58; P = 0.79) or disease-specific survival (DFS, 0.86; 95% CI 0.50–1.50; P = 0.76) was observed with no PORT.

Conclusions

PORT isn’t necessary for patients with LA-HNSCC who are treated for the first time as long as the head and neck cancer surgeon adhere to appropriate surgical concepts. The indications of PORT for patients with LA-HNSCC need to be further discussed.

De-Escalation Strategies of (Chemo)Radiation for Head-and-Neck Squamous Cell Cancers-HPV and Beyond

Oncological outcomes for head-and-neck squamous cell carcinoma (HNSCC) patients are still unsatisfactory, especially for advanced tumor stages. Besides the moderate survival rates, the prevalence of severe treatment-induced normal tissue toxicities is high after multimodal cancer treatments, both causing significant morbidity and decreasing quality of life of surviving patients. Therefore, risk-adapted and individualized treatment approaches are urgently needed for HNSCC patients to optimize the therapeutic gain. It has been a well-known fact that especially HPV-positive oropharyngeal squamous cell carcinoma (OSCC) patients exhibit an excellent prognosis and may therefore be subject to overtreatment, resulting in long-term treatment-related toxicities. Regarding the superior prognosis of HPV-positive OSCC patients, treatment de-escalation strategies are currently investigated in several clinical trials, and HPV-positive OSCC may potentially serve as a model for treatment de-escalation also for other types of HNSCC. We performed a literature search for both published and ongoing clinical trials and critically discussed the presented concepts and results. Radiotherapy dose or volume reduction, omission or modification of concomitant chemotherapy, and usage of induction chemotherapy are common treatment de-escalation strategies that are pursued in clinical trials for biologically selected subgroups of HNSCC patients. While promising data have been reported from various Phase II trials, evidence from Phase III de-escalation trials is either lacking or has failed to demonstrate comparable outcomes for de-escalated treatments. Therefore, further data and a refinement of biological HNSCC stratification are required before deescalated radiation treatments can be recommended outside of clinical trials.

Dose Reduction to the Swallowing Apparatus and the Salivary Glands by De-Intensification of Postoperative Radiotherapy in Patients with Head and Neck Cancer: First (Treatment Planning) Results of the Prospective Multicenter DIREKHT Trial

Aim: Evaluating radiotherapy treatment plans of the prospective DIREKHT trial (ClinicalTrials.gov, NCT02528955) investigating de-intensification of radiotherapy in patients with head and neck cancer. Patients and Methods: The first 30 patients from the DIREKHT trial of the leading study centre were included in this analysis. Standard treatment plans and study treatment plans derived from the protocol were calculated for each patient. Sizes of planning target volumes (PTVs) and mean doses to organs at risk were compared using the Student’s t-test with paired samples. Results: Mean PTV3 including primary tumor region and ipsilateral elective neck up to a dose of 50 Gy in the study treatment plans was 662 mL (+/− 165 mL standard deviation (SD)) and therefore significantly smaller than those of the standard treatment plans (1166 mL (+/− 266 mL SD). In the medial and inferior constrictor muscles, cricopharyngeal muscle, glottic and supraglottic laryngeal areas, arytenoid cartilages, contralateral major salivary glands highly significant dose reductions (p < 0.0001) of more than 10 Gy were achieved in study treatment plan compared to standard treatment plan. Conclusion: De-intensification of radiotherapy led to smaller planning target volumes and clinical relevant dose reductions in the swallowing apparatus and in the contralateral salivary glands.

Age-dependent hemato- and nephrotoxicity in patients with head and neck cancer receiving chemoradiotherapy with weekly cisplatin

BACKGROUND AND PURPOSE

In cases of simultaneous chemoradiotherapy (CRT), early recognition of toxic side effects is important, as drug discontinuation may prevent further injury. It appears favorable to undertake further steps to investigate whether patient subgroups behave differently depending on their toxicity profile.

METHODS

We retrospectively analyzed 125 consecutive patients with non-metastasized carcinoma of the head and neck who were treated with CRT (cisplatin 40 mg/m² weekly) in 2013/2014. Patients were planned to receive six cycles of cisplatin. Statistical analyses were performed using the chi² test, t-test, Kaplan-Meier method, and the log-rank test, as appropriate.

RESULTS

Eighty-six patients did not reach the intended sixth cycle (68.8%; 60.0% of whom were ≥60 years, p < 0.05). Acute kidney injury (glomerular filtration rate <60 mL/min/1.73m²) was the most common reason for drug discontinuation (26.7%; 82.6% of whom were ≥60 years; p < 0.01), followed by leukopenia <3/nL (23.3%; 75% of whom were <60 years; p < 0.01) and infection (11.6%). Patients who underwent ≥5 cycles were associated with prolonged overall survival and metastasis-free survival after CRT (p < 0.02; median follow-up 24 months), especially patients <60 years.

CONCLUSION

Acute kidney injury was the most common side effect in patients ≥60 years, whereas leukopenia characteristically occurred significantly more often in younger patients. Discontinuing cisplatin during CRT was associated with a worse outcome, especially in patients <60 years.

Addition of chemotherapy to hyperfractionated radiotherapy in advanced head and neck cancer-a meta-analysis

BACKGROUND

Adding concurrent chemotherapy (CTx) to definitive radiation therapy (RT) in patients with locally advanced head and neck squamous cell carcinoma (LA-HNSCC) improves overall survival. A comparable effect has been reported for hyperfractionated radiotherapy (HFX-RT) alone. Adding concurrent CTx to HFX-RT has been investigated in multiple trials, yet an evident effect on oncological outcomes and toxicity profile has not been established to date. Thus, the aim of the current study was to perform a meta-analysis on the clinical outcome and toxicity of the addition of CTx to HFX-RT.

PATIENTS AND METHODS

We performed a literature search for randomized controlled trials comparing HFX-RT alone to HFX-RT + concurrent CTx in patients with LA-HNSCC undergoing definite RT. A meta-analysis was performed using the event rates and effect-sizes for overall survival (OS), progression-free survival (PFS), cancer-specific survival (CSS), distant metastasis-free survival and distant recurrence-free interval (DMFS/DMFI) and locoregional recurrence (LRR) as investigated endpoints. Furthermore, we compared selected acute and late toxicities in the included studies. Statistical analysis was performed using the Microsoft Excel (Microsoft, Redmont, WA, USA) add-in MetaXL 5.3 (EpiGear International, Sunrise Beach, Australia), utilizing the inverse variance heterogeneity model.

RESULTS

We identified six studies (n = 1280 patients) randomizing HFX-RT alone and the concurrent addition of CTx. OS was significantly improved in the HFX-RT + CTx group (HR = 0.77, CI95% = 0.66-0.89; p = <0.001). We found similar results in PFS (HR = 0.74, CI95% = 0.63-0.87; p < 0.001) and CSS (HR = 0.72, CI95% = 0.60-0.88; p = 0.001). In contrast, acute toxicities (≥grade 3 mucositis, ≥grade 3 dysphagia) and late adverse events including ≥grade 3 xerostomia, ≥grade 3 subcutaneous, ≥grade 3 bone, ≥grade 3 skin toxicity, and ≥grade 3 dysphagia did not significantly differ between the two groups.

CONCLUSION

The addition of CTx to HFX-RT in the definitive treatment of advanced LA-HNSCC improves OS, CSS, PFS, and LRR without a significant increase in high-grade acute and late toxicities.