boron and Head-and-Neck-Neoplasms

Boron neutron capture therapy (BNCT) has been extant for decades and continues to be practiced in many centers around the globe. Most of the active clinical trials utilize boronophenylalanine as the drug containing boron atoms. The important aspect that has been added to the BNCT practice is the use of an F-18 radiolabeled analog for ascertaining targeting and monitoring follow-up studies. The recent widespread application of therapeutic radiopharmaceuticals, especially peptides (somatostatin analogs), prostate-specific antigen-binding ligands, or immunomolecules, offers the ambit for invention of new tumor-specific BNCT agents, especially for BNCT-susceptible tumors, that is, locoregional cancers such as head and neck cancer. Such BNCT agents, when radiolabeled, can enable simultaneous imaging and/or therapeutic applications (depending on the radionuclide used) through multimodal approaches. Development of boron-rich moieties such as sodium borocaptate and neutral carboranes combined with tumor-targeting moieties can lead to a new horizon in BNCT. The review covers various aspects of drug design, tumor targeting, and possible future radiopharmaceutical development for multimodal theranostic application in humans.

Topics: Boron; Boron Compounds; Boron Neutron Capture Therapy; Head and Neck Neoplasms; Humans; Male; Precision Medicine; Radiopharmaceuticals

Boron neutron capture therapy (BNCT) is a binary modality that is used to treat a variety of malignancies, using neutrons to irradiate boron-10 (

Topics: Boron; Boron Neutron Capture Therapy; Brain Neoplasms; Head and Neck Neoplasms; Humans; Melanoma

Recently, boron neutron capture therapy (BNCT) has been attracting attention as a minimally invasive cancer treatment. In 2020, the accelerator-based BNCT with L-BPA (Borofalan) as its D-sorbitol complex (Steboronine®) for head and neck cancers was approved by Pharmaceutical and Medical Devices Agency for the first time in the world. As accelerator-based neutron generation techniques are being developed in various countries, the development of novel tumor-selective boron agents is becoming increasingly important and desired. The Japanese Society of Neutron Capture Therapy believes it is necessary to propose standard evaluation protocols at each stage in the development of boron agents for BNCT. This review summarizes recommended experimental protocols for in vitro and in vivo evaluation methods of boron agents for BNCT based on our experience with L-BPA approval.

Topics: Boron; Boron Compounds; Boron Neutron Capture Therapy; Head and Neck Neoplasms; Humans; Neutrons; Review Literature as Topic

Purpose To evaluate the effect of oxygen pressure during incubation with a (10)B-carrier on (10)B uptake capacity of cultured p53 wild-type and mutated tumor cells. Materials and methods Cultured human head and neck squamous cell carcinoma cell line transfected with mutant TP53 (SAS/mp53), or with a neo vector as a control (SAS/neo) was incubated with L-para-boronophenylalanine-(10)B (BPA) or sodium mercaptoundecahydrododecaborate-(10)B (BSH) as a (10)B-carrier at the (10)B concentration of 60 ppm for 24 h under aerobic (20.7% of oxygen) or hypoxic (0.28% of oxygen) conditions. Immediately after incubation, cultured tumor cells received reactor thermal neutron beams, and a cell survival assay was performed. (10)B concentration of cultured SAS/neo or SAS/mp53 cells incubated under aerobic or hypoxic conditions was determined with a thermal neutron guide tube. Results Hypoxic incubation significantly decreased (10)B concentration of cultured cells with a clearer tendency observed following BPA than BSH treatment in both SAS/neo and SAS/mp53 cells. Following neutron beam irradiation, SAS/mp53 cells showed significantly higher relative biological effectiveness values than SAS/neo cells because of the significantly lower radiosensitivity of SAS/mp53 to γ-rays than SAS/neo cells. Conclusion Oxygen pressure during incubation with a (10)B-carrier had a critical impact on (10)B uptake of cultured tumor cells.

Topics: Boron; Boron Neutron Capture Therapy; Carcinoma, Squamous Cell; Cell Survival; Drug Carriers; Head and Neck Neoplasms; Humans; Isotopes; Mutation; Oxygen; Radiopharmaceuticals; Squamous Cell Carcinoma of Head and Neck; Tumor Suppressor Protein p53

Photon beams used in IMRT treatments with high energies (>10 MV) are contaminated with neutrons. Measurement of this neutron dose is of significance to the overall risk estimate of high energy radiotherapy.. For measuring neutron doses a paired magnesium and boron coated magnesium chamber system was used. All measurements were performed inside the solid water phantom EasyCube using abdominal extensions. 4 different clinical treatment plans were studied.. The measured neutron dose showed to be homogeneous inside the phantom and increased with increased number of applied monitor units. The sum over all fractions showed neutron doses of 1-2 mGy, depending on the kind of treatment.. Using large conversion factors of 25 Sv/Gy, none of the studied treatment plans exceeded dose equivalents of 50 mSv for the whole treatment. This dose equivalent has to be considered whole body dose due to the homogeneous distribution of neutrons.

Topics: Boron; Calibration; Computer Simulation; Dose Fractionation, Radiation; Head and Neck Neoplasms; Humans; Magnesium; Male; Monte Carlo Method; Neutrons; Prostatic Neoplasms; Radiotherapy Dosage; Radiotherapy, Intensity-Modulated; Scattering, Radiation

Topics: Boron; Carcinoma, Squamous Cell; Cell Survival; Culture Media; Fast Neutrons; Head and Neck Neoplasms; Humans; Isotopes; Melanoma; Neutrons; Particle Accelerators; Radiotherapy Dosage; Tumor Cells, Cultured