Radiotherapy plays an important role of managing head and neck squamous cell carcinoma (HNSCC). Concurrent radiotherapy with radiosensitizing cisplastin chemotherapy is the standard of care (SOC) for non-operable locally advanced HNSCC. Cetuximab, a monoclonal antibody of epidermal growth factor receptor, was the most extensively studied targeted therapy as a chemo-sparing agent that was used concurrently with radiotherapy. Immunotherapy is used in the treatment of metastatic HNSCC. There is evidence to support the synergistic effect when combining radiotherapy with immunotherapy to potentiate anti-tumor immune response. There has been increasing interest to incorporate immune checkpoint inhibitor (ICI) with radiotherapy in the curative setting for HNSCC. In this review, we discuss the latest evidence that supports concurrent radiotherapy with cisplatin which remains the SOC for locally advanced HNSCC (LA-HNSCC). Cetuximab is suitable for patients who are not fit for cisplatin. We then summarize the clinical trials that incorporate ICI with radiotherapy for LA-HNSCC in concurrent, neoadjuvant, and adjuvant settings. We also discuss the potential of combining immunotherapy with radiotherapy as a treatment de-escalating strategy in HPV-associated oropharyngeal carcinoma. Finally, the pre-clinical and clinical evidence of the abscopal effect when combining stereotactic body radiotherapy with ICIs is presented.

The treatment of head and neck cancers (HNCs) encompasses a complex paradigm involving a combination of surgery, radiotherapy, and systemic treatment. Locoregional recurrence is a common cause of treatment failure, and few patients are suitable for salvage surgery. Reirradiation with conventional radiation techniques is challenging due to normal tissue tolerance limits and the risk of significant toxicities. Stereotactic body radiotherapy (SBRT) has emerged as a highly conformal modality that offers the potential for cure while limiting the dose to surrounding tissue. There is also growing research that shows that those with oligometastatic disease can benefit from curative intent local ablative therapies such as SBRT. This review will look at published evidence regarding the use of SBRT in locoregional recurrent and oligometastatic HNCs.

Aim: The management of low-grade gliomas (LGGs) is evolving with new insights into disease biology. Furthermore, recently, the phase III INDIGO¹ study highlighted the benefits of an IDH inhibitor, vorasidenib, in treating residual or recurrent grade 2 IDH-mutant gliomas following surgery alone. We aimed to characterise the current patterns of care for patients with LGGs in Australia and New Zealand, including the role of vorasidenib. Methods: An online survey examining respondents’ practice setting, caseload, and preferred treatment approach to three clinical scenarios was distributed through the Cooperative Trials Group for Neuro-Oncology, New Zealand Aotearoa Neuro-Oncology Society, and the Australian and New Zealand Society for Neuropathology in December 2023 with three reminders in April, June, and September of 2024. Results: The survey response rate was 19.6% (57/291), 87.7% from Australia, and 12.3% from New Zealand, spanning medical oncology (45.7%), pathology (22.8%), radiation oncology (17.5%), and neurosurgery (14.0%). Case 1 examined an IDH-mutant grade 2 astrocytoma following gross total resection. Observation alone was recommended by 93%. Case 2 examined an incompletely resected IDH-mutant grade 2 astrocytoma. If feasible, 38% recommended further surgery and 83% adjuvant chemotherapy and radiotherapy. After 12 months of disease stability, 53% of the respondents preferred vorasidenib over the existing therapies. Case 3 examined an incompletely resected IDH-mutant grade 3 oligodendroglioma. No respondents recommended observation alone, with 26% recommending salvage surgery and 97% recommending further chemotherapy and radiotherapy. Conclusions: This study describes current management practices for LGGs in Australia and New Zealand, showing ongoing variation and a cautious approach to integrating IDH inhibitors. This highlights the critical role of multidisciplinary team-based decision-making in increasingly complex clinical situations.

Isocitrate dehydrogenase (IDH)‐mutant low‐grade and high‐grade gliomas are primary brain cancers with slower growth rates and longer survival than IDH‐wildtype counterparts. However, these tumors are fatal and because of the younger age of patients, result in significant morbidity and loss of productivity. Several management options are available at initial diagnosis for IDH‐mutant gliomas (including close surveillance, surgery, radiation therapy, chemotherapy and/or targeted therapies either alone or in combination), however, there is limited data about optimal timing and sequencing. When considering treatment, the risks associated with uncontrolled disease should be weighed against potential treatment‐associated toxicities given the expected long overall survival times for many patients. Preservation of cognition, neurological function and quality of life remain a priority. Treatment decisions should therefore be made in the context of a neuro‐oncology multidisciplinary team, and incorporating the patient's wishes and expectations. The management of recurrent IDH‐mutant glioma is not well defined. This expert position statement aims to provide an Australian perspective on the evidence base and available treatments for contemporaneous management of IDH‐mutant glioma in adults.

Introduction: Despite their benefit, current anti-EGFR therapies are limited by narrow efficacy profiles due to dose-limiting toxicities. This phase 2 open-label study evaluated the efficacy and safety of ABT-806, an EGFR-targeting antibody that is tumor specific, in patients with advanced EGFR-expressing tumors including head and neck cancers (H&NC) and squamous cell carcinoma (SCC) of other sites. Methods: Patients with advanced H&NC (cohort A) or SCC of other sites (cohort B) were enrolled in the study. ABT-806 was administered as monotherapy at a dose of 24 mg/kg intravenously using a twice weekly dosing schedule until unacceptable toxicity and/or evidence of disease progression. Adverse events (AEs) were graded using the National Cancer Institute Common Terminology Criteria for Adverse Events v4.0; tumor response was assessed using the Response Evaluation criteria in Solid Tumors v1.1. EGFR status was assessed with mAb806 and EGFRvIII immunohistochemistry and correlated with outcomes. Results: ABT-806 was well tolerated with no grade 3+ treatment-related AEs. Disease stabilization was observed in two patients (14%) and for a median duration of 19.5 weeks. This included one patient from cohort A and one patient from cohort B. Progression-free survival and overall survival was not significantly different between the two cohorts. Conclusions: Although clinical activity was limited in this small, heavily pre-treated, and biomarker-unselected population, ABT-806 demonstrated an excellent safety profile with minimal classical EGFR-related toxicity. These findings support the development of more tumor-specific EGFR antibodies for use, particularly in combinatorial regimens.