A study of the 10B-enriched Boronophenylalanine-fructose complex(10BPA-F) infusion procedure in potential BNCT patients, including three skin melanomas of extremities, was performed. 10B concentration in tumor(T), blood(B), skin(S) were measured to determine tumor/blood(T/B) and skin/blood(S/B) ratios. T/B ratio for three melanoma patients was in the range 1.48-3.82(average 2.56 ± 0.69). S/B ratio was in the range 0.81-1.99(average 1.29 ± 0.35). Results showed that T/B ratio of nodular metastasis melanoma was higher than superficial spreading melanoma. 10B concentration in skin was higher than blood, which was helpful to avoid over-dose in normal skin.

A phase I/II clinical trial for treating malignant melanoma by boron neutron capture therapy (BNCT) was designed to evaluate whether the world’s first in-hospital neutron irradiator (IHNI) was qualified for BNCT. In this clinical trial planning to enroll 30 patients, the first case was treated on August 19, 2014. We present the protocol of this clinical trial, the treating procedure, and the clinical outcome of this first case. Only grade 2 acute radiation injury was observed during the first four weeks after BNCT and the injury healed after treatment. No late radiation injury was found during the 24-month follow-up. Based on positron emission tomography-computed tomography (PET/CT) scan, pathological analysis and gross examination, the patient showed a complete response to BNCT, indicating that BNCT is a potent therapy against malignant melanoma and IHNI has the potential to enable the delivery of BNCT in hospitals.

In-hospital neutron irradiator(IHNI) was specially designed for boron neutron capture therapy(BNCT).On the both sides of the reactor core,there are two neutron beams.One is thermal neutron beam,and the other opposite to the thermal beam,is epithermal neutron beam.A small thermal neutron beam is specially designed for the measurement of blood boron concentration by the prompt gamma neutron activation analysis(PGNAA).The six experiments were completed during startup.The results show that the maximum continuous operation time at full power is 12 h,and the final excess reactivity is 4.2 mk.The radiation dose rates at different rooms meet the designed requirement.When the positive reactivity with 4.2 mk is inserted into the reactor suddenly,the power will increase to peak power,and then,it will turn to the normal value due to the negative temperature effect,and the release result of reactivity shows the inherent safety of IHNI.

In-hospital Neutron Irradiator (IHNI) was specially designed for Boron Neutron Capture Therapy (BNCT), the rated power of IHNI is 30kW, corresponding to the neutron flux density 1×1012n·cm−2·s−1 in reactor core. IHNI is an undermoderated reactor of pool-tank type, and UO2 with enrichment of 12.5% as fuel, light water as coolant and moderator, and metallic beryllium as reflector. The fission heat produced by the reactor is removed by the natural convection. On the both sides of the reactor core, there are two neutron beams, one is thermal neutron beam, and the other opposite to the thermal beam, is epithermal neutron beam. A small thermal neutron beam is specially designed for the measurement of blood boron concentration by the Prompt Gamma Neutron Activation Analysis (PGNAA). The decay constants and shares of six group of ordinary delayed neutron and nine group of photoneutron were obtained by WIMS code. Based on that, the relationship between the reactivity and the reactor period was calculated through the inhour equation. In this way, the excess reactivity and the reactivity worthies of the components (control rod, water, etc) in the core are obtained by periodic method during the startup of the reactor. The six test experiments were completed during startup, The test results show that the maximum continuous operation time at full power is 12h; the excess reactivity at cold clean state of the core is 4.2mk; The radiation levels at technical rooms are within the specified values at full power operation. When the positive reactivity with 4.2 mk is inserted into the reactor suddenly, the power will be increased to peak power, and then, it will turn to the normal value due to the negative temperature effect, this experiment shows the inherent safety of IHNI.

Invasive nonfunctional pituitary adenomas (NFPAs) are difficult to completely resect and often develop tumor recurrence after initial surgery. Currently, no medications are clinically effective in the control of NFPA. Although radiation therapy and radiosurgery are useful to prevent tumor regrowth, they are frequently withheld because of severe complications. Boron neutron capture therapy (BNCT) is a binary radiotherapy that selectively and maximally damages tumor cells without harming the surrounding normal tissue. Folate receptor (FR)-targeted boron-10 containing carbon nanoparticles is a novel boron delivery agent that can be selectively taken up by FR-expressing cells via FR-mediated endocytosis. In this study, FR-targeted boron-10 containing carbon nanoparticles were selectively taken up by NFPAs cells expressing FR but not other types of non-FR expressing pituitary adenomas. After incubation with boron-10 containing carbon nanoparticles and following irradiation with thermal neutrons, the cell viability of NFPAs was significantly decreased, while apoptotic cells were simultaneously increased. However, cells administered the same dose of FR-targeted boron-10 containing carbon nanoparticles without neutron irradiation or received the same neutron irradiation alone did not show significant decrease in cell viability or increase in apoptotic cells. The expression of Bcl-2 was down-regulated and the expression of Bax was up-regulated in NFPAs after treatment with FR-mediated BNCT. In conclusion, FR-targeted boron-10 containing carbon nanoparticles may be an ideal delivery system of boron to NFPAs cells for BNCT. Furthermore, our study also provides a novel insight into therapeutic strategies for invasive NFPA refractory to conventional therapy, while exploring these new applications of BNCT for tumors, especially benign tumors.

Optimization design for the moderation layer and reflection layer of the epithermal neutron duct at in-hospital neutron irradiator mark 1(IHNI-1) reactor is carried out by using MCNP in this paper. Firstly, six moderator schemes combined with FLUENTAL are compared with Al materials, and two moderation optimization schemes which can obtain intensive epithermal neutron flux density at exit of this duct are chosen. Secondly, based on these two moderation schemes, the optimization design for reflectors around the moderator is introduced, and the recommended reflector schemes are given. Finally, based on the moderation layer and reflection layer optimization schemes, the neutron and gamma space distribution of the epithermal neutron beam at exit of this duct are detailed calculated.

硼中子俘获疗法(boron neutron capture therapy,BNCT)的基本原理是基于核裂变反应.当非放射性硼(10B)元素受到低能量中子照射后即发生核裂变,从而产生高能量α粒子(4He),其本身衰变为锂(7Li)核[10B(n,α)7Li].7Li核和α粒子的射程大约只有1个细胞的直径(10μm),所以其引起的损伤范围也仅局限于带有1oB的细胞.因此,无论从生物学或生理学角度上来看,BNCT是新的一种靶向性放疗[1].BNCT要取得成功,首先必须选择性地运送足量10B到肿瘤细胞内,同时保持周围正常细胞不含或仅含极低浓度10B。

According to the characteristics and operation condition of IHNI-1 reactor, a subchannel model is developed in this paper. It also has been verified that the model is reasonable and effective in IHNI-1's thermal hydraulic analysis. Using the model, some thermal parameters of IHNI-1reactor are calculated. The relation between the core's coolant inlet flux and outlet temperature is analyzed, and the variation of rod temperature with reactor power is also calculated.

Using the WIMS/CITATION program,a neutronic parameter calculating model for the IHNI-Ⅰ(In-Hospital Neutron Irradiator Mark I) reactor is presented in this paper.In the calculations of the cell group parameters,the bundle model is adopted.The control rod,the top Be reflector,the bottom Be reflector,the side Be reflector and each circle fuel rod of the core are taken as different cell types.In the whole core calculation,the R-z model is adopted by using the CITATION code.The power distribution,the reactivity worth of the control rod and the top beryllium,the temperature coefficient and the burnup are calculated.It is shown that the results agree with the values in literature,and the method is appropriate for the physical calculation of the IHIN-Ⅰ reactor.

Numerical calculation for the equivalent surface source of the thermal neutron duct of in-hospital neutron irradiator mark 1(IHNI-1) reactor is carried out using MCNP Monte Carlo code. Cold clean criticality of B core is searched. Neutron beam parameters at the exit of thermal neutron duct are calculated. Equivalent neutron and γ surface sources for BNCT are built using equivalent surface source model. And these sources are reliable to calculate absorbed dose distribution in equivalent model of head quickly.

The construction of in-hospital neutron irradiator (IHNI) started in 2007. Its building construction was completed in Dec. 2008, and the installation and test of the relevant systems were completed in Mar. 2009. The first criticality was achieved on Dec. 7, 2010. The reactor reached the full power on Jan. 22, 2010. The test results show that the final excess reactivity is 4.2 mk; the maximum continuous operation time at full power is 12 h and the power wave is less then 0.3 % during full power operation; when the positive reactivity with 4.2 mk is inserted into the reactor suddenly, the power will be increased to 85.7 kW at the time of 229 s, and then, it will turn to the normal value due to the negative temperature effect.The release result of reactivity shows the inherent safety of reactor.

A temperature-dependent neutron cross-section library for MCNP in in-hospital neutron irradiator mark 1 reactor was generated using NJOY software. Accounting for the temperature range for reactor operation, a compact ENDF (ACE) data library was created. The accuracy of the self-making library was validated by comparing data with MCNP/4B standard library and the results were tested by ICSBEP (International Criticality Safety Benchmark Evaluation Project) benchmark problems, which was used in the calculation of Doppler temperature coefficient. Influence of different parameters in the processing was also analyzed. The results showed that the ACE format library produced in this paper was correct and could be used reliably for physics design at IHNI-1 reactor.

To calculate the fission product poisoning and burnup of the reactor accurately, the paper sets up the coupled calculation methods based on MCNP code and ORIGEN2 code and program data translation, cross section revision and date interface codes. Making use of elaborate reactor model to calculate the fission product poisoning and burnup for in-hospital neutron irradiator mark 1 reactor.

In 2010, the commissioning of in-hospital neutron irradiator (IHNI) and its systems were completed. The operation with power started since then. The IHNI has operated by 99 times. The release of total energy is 1 832.42 kW·h with the corresponding integral neutron flux of 2.198 9×1017 cm-2. The test operation data shows that the operation values of IHNI and its relevant systems are smaller than the limited value, which manifests that IHNI is safe and reliable.

The design of in hospital neutron irradiator (IHNI) and its systems were introduced, and the performance and characteristics of IHNI were described. In order to test the inherent safety of IHNI, the experiment of 4.2 mk reactivity release was done. The experimental results showed that the peak power of IHNI was 85.7 kW at the time of 229 s after 4.2 mk reactivity release, and then, the power decreased owing to the negative temperature coefficient of moderator. The radiation dose rates at different rooms were lower than the standard value.

The paper briefly interprets the obvious progress of the boron neutorn capture therapy (BNCT) in the new era. It includes the BNCT clinical positioning, the tumour recurrence exploring, the boron concentration quantifed detecting, the targeting boron compound composing and the in hospitor neutron source irradintors setting up. The enlargement of these bottle necks in BNCT developing might be the preview of personalizing and routine BNCT.

The paper set up the coupled calculation methods of criticality and burnup based on WIMS code and MCNP code, and validated the method. Through the calculation results of cells and the comparison of burnup experiments of Xi’an pulsed reactor, the validity and rationality of the coupled code were proved. The article utilized the coupled code to compute and analyze the burnup of in hospital neutron irradiator mark 1(IHNI-1) reactor at last.

The kinetic parameters of in-hospital neutron irradiator mark 1 (IHNI-1) reactor, effective delayed neutron fraction and neutron generation time are calculated by CKPWC（calculating kinetic parameters based on WIMS and CITATION）program based on the calculated results of WIMS and CITATION. The cell homogenized cross section and 69-group flux density are calculated by WIMS. Flux density and adjoint flux density are obtained based on 4-group diffusion calculation using CITATION. The kinetic parameters are calculated by CKPWC based on the results of WIMS and CITATION. The analysis based on the calculation indicates that the energy group structure has a significant effect on the result of kinetic parameter. An appropriate energy group structure is given in this paper. To verify the accuracy of the method, Xi’an Pulsed Reactor is benchmarked and the result is corresponded to its design value.

Using WIMS & CITATION program, the neutronic parameters calculating model of in-hospital neutron irradiator mark 1(IHNI-1) reactor is presented in this paper.The power distribution, reactivity worth of control rod and top beryllium, temperature coefficient and burnup are calculated. It proves that the results are consistent with the literature values and the method is appropriate to physical calculation of IHIN-1 reactor.