Long-Term Update of NRG/RTOG 0522: A Randomized Phase 3 Trial of Concurrent Radiation and Cisplatin With or Without Cetuximab in Locoregionally Advanced Head and Neck Cancer

Outcomes following IMRT alone in head and neck squamous cell carcinoma ordinarily managed with concurrent chemo-radiotherapy

PURPOSE/OBJECTIVE(S)

We report outcomes following IMRT-alone in patients with head-and-neck squamous cell carcinoma (HNSCC) ordinarily managed with concurrent chemo-radiotherapy.

MATERIALS/METHODS

HNSCC (excluding T1-2 N0) patients treated with IMRT-alone from 2005 to 2019 were included and restaged according to TNM-8. Overall survival (OS) was stratified by TNM-8 stage subgroups within HPV-positive (HPV + ) and separately within HPV-negative (HPV-) HNSCC. Multivariable analysis (MVA) identified prognostic factors for OS.

RESULTS

A total of 460 patients with HPV + and 623 HPV- HNSCC were identified. Reasons for chemotherapy omission were: age > 70 years and/or frailty (n = 551, 51 %), cisplatin contraindication (n = 241, 22 %), patient' preference (n = 106, 10 %), and clinician's decision (n = 185, 17 %). IMRT was delivered mostly using altered-fractionation: moderately-accelerated (70 Gy/35 fractions [f]/6 weeks [w], 55 %), hypofractionated (60 Gy/25f/5w, 14 %), and hyperfractionated-accelerated (64 Gy/40f/4w, 25 %). Median follow-up was 5.0 years. Five-year OS for HPV + stage-I-single node, stage-I-multiple nodes, stage-II-T1-2 N2, stage-II-T3 N0-N2, and stage-III were 90 %, 79 %%, 80 %, 64 %, and 33 %, and for HPV- stage III, IVA, and IVB were 47 %, 27 %, and 13 %, respectively. MVA confirmed lower OS in HPV + stage-I-multiple nodes (p = 0.03), II-T3 N0-N2 and III (vs stage-I-single node) and HPV- stage IVA/IVB (vs III) (p < 0.01), and marginally lower OS in HPV + stage-II-T3 N0-2 (vs I-single node) (p = 0.07).

CONCLUSION

Altered fractionated IMRT-alone is a valid option for patients with HPV + stage I-single node HNSCC, and an acceptable alternative for elderly/frail or cisplatin ineligible patients with HPV + stage I-multiple nodes and T1-2 N2 HNSCC. Patients with HPV + T3-T4 or N3 and HPV- stage III/IV HNSCC had unsatisfactory OS, requiring further research into alternative options.

DAHANCA19: A randomized phase III study of primary curative (chemo)-radiotherapy and the EGFR-inhibitor zalutumumab for squamous cell carcinoma of the head and neck

BACKGROUND AND PURPOSE

Antibodies against the Epidermal Growth Factor receptor is suggested to decrease tumour failure and increase survival rates of patients (pts) with Head and Neck Squamous Cell Carcinomas (HNSCC) when combined with radiotherapy. This study aimed to evaluate if concurrent treatment with the EGFR inhibitor zalutumumab during (chemo-)radiotherapy improved outcome in pts with HNSCC.

MATERIALS AND METHODS

Overall, 608 eligible pts with biopsy-verified HNSCC of the oral cavity, pharynx and larynx were accrued November 2007 to June 2012. Pts were randomized to a control-arm of primary accelerated radiotherapy predominantly 66-68 Gy, 2 Gy/fraction, 6fx/week and concomitant daily hypoxic radiosensitisation with nimorazole. St. III-IV carcinomas received weekly cisplatin 40 mg/m2 in addition to nimorazole. The zalutumumab-arm was identical to the control-arm plus zalutumumab 8 mg/kg. First dose was given the week before start of treatment and continued weekly during radiotherapy. Analyses were performed as intention-to-treat. Primary endpoint was loco-regional failure. Secondary endpoints were disease-specific survival and overall survival.

RESULTS

In total, 307 pts were in the control-arm and 301 in the zalutumumab-arm. Median follow-up was 59 months. Patient and tumour parameters were well balanced. The 5-year loco-regional failure rate was 24 % in the zalutumumab-arm and 18 % in the control-arm; Hazard Ratio (HR) 1.16 (95 % CI 0.84-1.59); disease-specific survival; HR 1.04 (95 % CI 0.73-1.50) and overall survival; HR 1.21, (0.91-1.61). Effect of zalutumumab was not influenced by HPV/p16 status.

CONCLUSION

Addition of concomitant zalutumumab to primary (chemo-)radiotherapy and concomitant nimorazole for HNSCC did not increase loco-regional control nor disease-specific or overall survival.

Treatment outcomes for human papillomavirus negative oropharyngeal cancer: A meta-analysis

BACKGROUND

Current treatment guidelines for HPV-negative oropharyngeal squamous cell carcinoma (OPSCC), the predominant form of OPSCC in Asia, are largely extrapolated from the evidence available from HPV-associated OPSCC due to a paucity in the literature in terms of the best treatment option for these cancers.

METHODS

Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and clinical trial registries were searched from January 01, 2009 to June 20, 2023 for studies comparing at least two interventions [randomized (RCT)and non-randomized] performed as primary curative treatment in HPV-negative OPSCC. Random effects model was used for the meta-analysis.

RESULTS

Forty-seven studies could be included (randomized controlled trials: 12, 1230 participants; non-randomized cohort studies: 35, 44253 participants). The largest comparison in the non-randomized studies was between upfront surgery and non-surgical intervention [RT/concurrent chemoradiation (CRT)] with 24 studies. The outcomes in the former for overall survival (HR:0.63, 95 %C.I: 0.56, 0.71) and disease-free survival (HR:0.48, 95 %C.I: 0.30, 0.76) were found to be superior (risk of bias: "high" or "serious"). Due to the lack of reporting of treatment-related toxicity and health-related quality of life, meta-analysis could not be performed for these outcomes.

CONCLUSION

and Relevance: Upfront surgery showed superior outcomes in terms of OS and DFS compared with non-surgical modalities in HPV-negative OPSCC, but the observed differences may be due to confounding bias. Toxicity and quality of life reporting was sparse.

Correlates of Cetuximab Efficacy in Recurrent and Metastatic Head and Neck Squamous Cell Carcinoma Previously Treated With Immunotherapy

PURPOSE

Immune checkpoint inhibitors (ICIs) are now first-line therapy for most patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC), and cetuximab is most often used as subsequent therapy. However, data describing cetuximab efficacy in the post-ICI setting are limited.

METHODS

We performed a single-institution retrospective analysis of patients with R/M HNSCC treated with cetuximab, either as monotherapy or in combination with chemotherapy, after receiving an ICI. We extracted objective response rate (ORR), duration of treatment (DOT), and overall survival (OS) and compared them on the basis of patient characteristics. Multivariable models assessed associations between patient and tumor characteristics and outcomes.

RESULTS

We identified 70 patients treated with cetuximab after an ICI. The mean age was 67.6 years, with 60% having virus-associated HNSCC. Overall, the ORR was 21.4%, the median DOT was 1.9 months, and the median OS was 6.3 months. Patients receiving cetuximab with chemotherapy had a higher ORR (27.7% v 8.7%) and longer median DOT but similar OS compared with monotherapy. Virus-independent HNSCC had higher ORR (28.6% v 10.7%), longer DOT (3.3 v 1.2 months; hazard ratio [HR], 0.47 [95% CI, 0.25 to 0.90]), and longer OS (8.1 v 4.6 months; HR, 0.40 [95% CI, 0.19 to 0.83]). In multivariable models, virus-independent disease and negative smoking history were associated with improved OS. Concurrent chemotherapy, age, and sex were not associated with differences in OS. When assessing genomic data, TP53 mutations were associated with improved DOT (HR, 0.33 [95% CI, 0.15 to 0.70]) and OS (HR, 0.38 [95% CI, 0.17 to 0.86]).

CONCLUSION

Cetuximab-based therapy shows limited efficacy in R/M HNSCC post-ICI, although outcomes were better in virus-independent HNSCC and nonsmokers. The findings may improve prognostication and patient selection for cetuximab after ICI in R/M HNSCC.

Chromosomal instability increases radiation sensitivity

Continuous chromosome missegregation over successive mitotic divisions, known as chromosomal instability (CIN), is common in cancer. Increasing CIN above a maximally tolerated threshold leads to cell death due to loss of essential chromosomes. Here, we show in two tissue contexts that otherwise isogenic cancer cells with higher levels of CIN are more sensitive to ionizing radiation, which itself induces CIN. CIN also sensitizes HPV-positive and HPV-negative head and neck cancer patient derived xenograft (PDX) tumors to radiation. Moreover, laryngeal cancers with higher CIN prior to treatment show improved response to radiation therapy. In addition, we reveal a novel mechanism of radiosensitization by docetaxel, a microtubule stabilizing drug commonly used in combination with radiation. Docetaxel causes cell death by inducing CIN due to abnormal multipolar spindles rather than causing mitotic arrest, as previously assumed. Docetaxel-induced CIN, rather than mitotic arrest, is responsible for the enhanced radiation sensitivity observed in vitro and in vivo, challenging the mechanistic dogma of the last 40 years. These results implicate CIN as a potential biomarker and inducer of radiation response, which could provide valuable cancer therapeutic opportunities.

Statement of Significance

Cancer cells and laryngeal tumors with higher chromosome missegregation rates are more sensitive to radiation therapy, supporting chromosomal instability as a promising biomarker of radiation response.

Anti‑epidermal growth factor receptor monoclonal antibody therapy in locally advanced head and neck cancer: A systematic review of phase III clinical trials

The present systematic review evaluated the effectiveness of anti-EGFR therapy in combination with radiotherapy (RT) or with chemoradiation compared with the existing standard of care for the treatment of locally advanced head and neck squamous cell carcinoma (LAHNSCC). The PubMed, SCOPUS, EMBASE and COCHRANE databases were searched and 12 phase III randomized controlled trials were included. The effectiveness of the anti-EGFR monoclonal antibody cetuximab was evaluated in nine trials. Nimotuzumab (one trial), zalutumumab (one trial) and panitumumab (one trial) were the monoclonal antibodies evaluated in the remaining three trials. One study tested the effectiveness of adding cetuximab to radical RT and found that patients with LAHNSCC exhibited improvement in locoregional control (LRC), overall survival (OS) and progression-free survival (PFS) compared with those of patients treated with RT alone. A total of three studies tested the effectiveness of adding an anti-EGFR agent to chemoradiation. Of these, a single institution study in which patients received cisplatin at 30 mg/m2 weekly, instead of the standard doses of 100 mg/m2 every 3 weeks or 40 mg/m2 every week, reported significant improvement in PFS with the addition of nimotuzumab to chemoradiotherapy without an improvement in overall survival. However, the other two studies indicated that, when added to standard chemoradiation, the anti-EGFR monoclonal antibodies cetuximab or zalutumumab did not improve survival outcomes. Two phase III trials evaluated RT plus an anti-EGFR agent compared with chemoradiation alone. Of these, one study reported inferior outcomes with cetuximab-RT in terms of OS and LRC, whereas the other study with panitumumab plus RT failed to prove the non-inferiority. Two trials evaluated induction chemotherapy followed by cetuximab-RT compared with chemoradiotherapy and reported no benefits in terms of OS or PFS. Furthermore, one study evaluated induction chemotherapy followed by cetuximab-RT compared with induction chemotherapy followed by chemoradiotherapy and found no improvement in OS or PFS. Finally, three phase III trials tested the effectiveness of cetuximab plus RT in the treatment of human papillomavirus-positive oropharyngeal carcinoma, and found it to be inferior compared with cisplatin-RT in terms of OS, PFS and failure-free survival. Based on the aforementioned findings, it is difficult to conclude that anti-EGFR therapy in any form has an advantage over conventional chemoradiation in the treatment of LAHNSCC.

Rethinking treatment paradigms: Neoadjuvant therapy and de-escalation strategies in HPV-positive head and neck cancer

Head and neck cancer (HNC) is the 6th most common cancer across the world, with a particular increase in HNC associated with human papilloma virus (HPV) among younger populations. Historically, the standard treatment for this disease consisted of combined surgery and radiotherapy or curative platinum-based concurrent chemoradiotherapy, with associated long term and late toxicities. However, HPV-positive HNC is recognized as a unique cancer subtype, typically with improved clinical outcomes. As such, treatment de-escalation strategies have been widely researched to mitigate the adverse effects associated with the current standard of care without compromising efficacy. These strategies include treatment de-escalation, such as novel surgical techniques, alternative radiation technologies, radiation dose and volume reduction, as well as neoadjuvant chemotherapies, immunotherapies, and combined therapies. Although these therapies show great promise, many of them are still under investigation due to hesitation surrounding their widespread implementation. The objective of this review is to summarize the most recent progress in de-escalation strategies and neoadjuvant therapies designed for HPV-positive HNC. While specific treatments may require additional research before being widely adopted, encouraging results from recent studies have highlighted the advantages of neoadjuvant chemotherapy and immunotherapy, as well as radiation and surgical de-escalation approaches in managing HPV-positive HNC.

Critical review of the current and future prospects of VEGF-TKIs in the management of squamous cell carcinoma of head and neck

As the prognosis for squamous cell carcinoma of the head and neck remains unsatisfactory when compared to other malignancies, novel therapies targeting specific biomarkers are a critical emerging area of great promise. One particular class of drugs that has been developed to impede tumor angiogenesis is vascular endothelial growth factor-tyrosine kinase inhibitors. As current data is primarily limited to preclinical and phase I/II trials, this review summarizes the current and future prospects of these agents in squamous cell carcinoma of the head and neck. In particular, the combination of these agents with immunotherapy is an exciting area that may be a promising option for patients with recurrent or metastatic disease, evidenced in recent trials such as the combination immune checkpoint inhibitors with lenvatinib and cabozantinib. In addition, the use of such combination therapy preoperatively in locally advanced disease is another area of interest.

Are we ready for deintensification in human papillomavirus-positive oropharyngeal carcinomas?

PURPOSE OF REVIEW

Excellent outcomes following contemporary treatment of human papillomavirus (HPV)-positive oropharyngeal carcinoma (HPV+ OPC) have prompted the exploration of deintensification approaches to minimize treatment-related toxicities. This review describes the landscape of deintensification to date (up to November 2022).

RECENT FINDINGS

Although several deintensification trials have been published, none are practice changing. Three phase III randomized-controlled trials studying cetuximab and radiation therapy vs. standard chemoradiotherapy all showed inferior outcomes. Although some phase II trials reported favourable outcomes, they are often single-arm trials without an adequate control arm, thereby limiting the ability to modify practice.

SUMMARY

Substantial effort has been expended to explore deintensification options for selected HPV+ OPC patients aiming to avoid unnecessary toxicity. Strategies have included replacing cisplatin with cetuximab, reduced chemotherapy or radiotherapy intensity, reduction of radiotherapy volumes and risk stratification after trans-oral surgery or following induction chemotherapy. Challenges remain in the current deintensification landscape, including identifying the most suitable candidates along with a choice of most appropriate deintensification strategies. Promising selection criteria included either static baseline features or kinetic characteristics of clinical-biological parameters. Practice-changing trials remain elusive, and the search continues to attempt optimization of the therapeutic ratio for these patients.