Kappadath, Srinivas Cheenu

TPS6138 Background: Patients with early-stage oral cavity cancer (OCC; T1-2N0M0; AJCC 8th edition) have a 20-30% risk of occult nodal metastases despite clinical and radiographic evaluations. Standard-of-care treatment for most patients includes elective neck dissection (END), which requires surgical removal of the regional cervical lymph nodes, even though 70-80% of these necks are disease-free. Sentinel lymph node biopsy (SLN Bx), a less invasive procedure, could assess the first echelon lymph nodes as an alternative to END, potentially reducing morbidity and costs. A pivotal clinical trial comparing SLN Bx to END (NCT#04333537) is underway to inform efforts to establish optimal disease management for early-stage OCC. Methods: To assess the efficacy of SLN Bx in this population, we activated an international, multi-institutional, prospective phase II/III trial in July 2020, randomizing patients to two surgical arms: SLN Bx and END. A node-negative 18 F-FDG PET/CT imaging biomarker study with centralized read was required before randomization. OCC patients with a positive PET/CT remained in a registry to compare imaging findings with final neck pathology. Given the current evidence on morbidity for SLN Bx versus END, the phase II was designed to determine whether the change in patient-reported neck and shoulder function and related quality of life (QOL) from baseline to 6 months after surgery, using the Neck Dissection Impairment Index (NDII), showed a signal of superiority of SLN Bx compared to END (minimum important difference ³ 7.5; one-sided a = 0.10; 90% power). As of December 2024, 261 patients had been randomized and 203 were analyzed for the “Go/No-Go” decision to move forward into phase III. The phase III portion is a non-inferiority (NI) trial with disease-free survival (DFS) as the primary endpoint (NI margin hazard ratio 1.34 based on a 5% absolute difference in 2-year DFS; one-sided a = 0.05; 80% power, and two interim looks). The change in NDII from baseline to 6 months after surgery is a hierarchical co-primary endpoint for phase III. Phase III opened in October 2025 upon receiving a “Go” signal from phase II. Target accrual for phase III is 686 node-negative PET/CT patients, including those randomized in phase II (425 additional patients). In addition to sites requiring radiotherapy and imaging credentialing, quality assurance will include central pathology review of all negative SLN Bx cases and surgeon credentialing through an education course with SLN Bx and END case review by the surgical co-chairs. A surgical quality assurance working group will review all trial SLN Bx and END procedures. As of 01/12/26, 351 patients have been screened, and 273 of the planned 686 have been randomized. Clinical trial information: NCT#04333537 .

Objectives: The practice parameter was revised collaboratively by the American College of Radiology (ACR), the American Brachytherapy Society (ABS), the American College of Nuclear Medicine (ACNM), the American Radium Society (ARS), the Society of Interventional Radiology (SIR), and the Society of Nuclear Medicine and Molecular Imaging (SNMMI). This document summarizes current evidence-based guidelines for the administration of Yttrium radioembolic therapy to the liver, including training requirements, evidence-based guidelines for administration, and safe practice for administration. Methods: This practice parameter was revised according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website (https://www.acr.org/ClinicalResources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters—Interventional and Cardiovascular Radiology of the ACR Commission on Interventional and Cardiovascular, Committee on Practice Parameters and Technical Standards—Nuclear Medicine and Molecular Imaging of the ACR Commission on Nuclear Medicine and Molecular Imaging and the Committee on Practice Parameters—Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ABS, the ACNM, the ARS, the SIR, and the SNMMI. Results: This review seeks not to be a comprehensive discussion of radiotherapy to the liver, but rather, seeks to provide a parameter for safe and effective therapy. We discuss the qualifications of physicians involved in this therapy, basic indications, contraindications, procedural work-up, safe-handling, and regulatory requirement for the administration of selective internal radiation therapy to patients that are likely to benefit. The goal of this document is not to define which patients are best treated by these therapies, as this is best determined for individual patients after multidisciplinary review. A consistent and evidence-based approach to therapy, however, would benefit all patients who are offered this therapy. This document seeks to provide a framework for current best practices for the administration of the 2 currently available radioembolization devices. Conclusions: As Yttrium-90 radiotherapy to the liver occupies a growing role in the treatment of primary and metastatic liver cancer, this review seeks to assist clinicians of all involved specialties to optimize the efficacy and safety of these procedures.

TPS6093 Background: Since patients with early-stage oral cavity cancer (OCC; T1-2N0M0; AJCC 8th ed) have a 20-30% rate of occult nodal metastases despite clinical and radiographic assessment, standard of care treatment includes elective neck dissection (END). Many patients have comprehensive surgical management of the regional cervical nodal basin even though the majority of those necks (70-80%) will not contain disease. Assessment of draining first echelon lymph nodes by sentinel lymph node (SLN) biopsy (Bx), a less invasive surgical procedure, may provide an alternative to END, while potentially reducing morbidity and cost. A decisive clinical trial comparing SLN Bx versus END can focus the HNC clinical and research community and resources on establishing the standard of care for management of the neck in early-stage OCC. Methods: In order to address the efficacy of SLN Bx in this population, we recently activated an international multi-institutional phase II/III prospective trial randomizing patients to two surgical arms: SLN Bx and END. PET/CT is an integral imaging biomarker in this trial. A node-negative PET/CT study with central read is required before randomization. Patients with a positive PET/CT central result will remain in a registry to compare imaging findings with final neck pathology. Given the current evidence available regarding morbidity for SLN Bx versus END, the phase II will determine if patient-reported neck and shoulder function and related QOL at 6 months after surgery using the Neck Dissection Impairment Index (NDII) shows a signal of superiority of SLN Bx compared to END. A total of 228 randomized patients with negative PET/CT for potential evaluation of shoulder-related morbidity with difference in 6-month NDII scores (minimum important difference ³7.5; one-sided a = 0.10; 90% power) will serve as the “Go/No-Go” decision to move forward into phase III. The phase III portion is a non-inferiority (NI) trial with disease-free survival (DFS) as the primary endpoint (NI margin hazard ratio 1.34 based on a 5% absolute difference in 2-year DFS; one-sided alpha 0.05; 80% power, and an interim look for efficacy at 67% of the events based on an O’Brien-Fleming boundary). The NDII at 6 months after surgery is a hierarchical co-primary endpoint for the phase III. Target accrual of phase III is 618 PET/CT negative patients, including those randomized in phase II (297 DFS events required for the final analysis). In addition to radiotherapy and imaging credentialing, quality assurance will include central pathology review of all negative SLN Bx cases and surgeon credentialing through an education course and SLN Bx and END case review by the surgical co-chairs. A surgical quality assurance working group will review all trial SLN Bx and END outcomes. As of 02/15/21, 7 patients have been screened and 6 of the planned 228 randomized patients in phase II have been enrolled. Clinical trial information: NCT04333537.