To Evaluate the Efficacy and Safety of Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) Combined With NBB-001 and NBB-002 for Patients With Recurrent Head and Neck Malignancies

This Phase II study, titled 'A Single-Arm, Open-Label Phase II Clinical Trial to Evaluate the Efficacy and Safety of Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) Combined with NBB-001 and NBB-002 for Patients with Recurrent Head and Neck Malignancies.', aims to assess the efficacy and safety of BNCT in patients with Recurrent Head and Neck Malignancies. Primary Objective: To evaluate the efficacy of Boron Neutron Capture Therapy (BNCT) in patients with recurrent head and neck malignancies.Secondary Objectives:To evaluate the efficacy of BNCT in patients with recurrent head and neck malignancies based on secondary efficacy endpoints;To characterize the pharmacokinetic (PK) profiles and radiation dosimetric characteristics of NBB-002 in patients with recurrent head and neck malignancies;To evaluate the safety of BNCT in patients with recurrent head and neck malignancies;To evaluate the equipment performance and equipment deficiencies of the boron neutron capture therapy system.