Abstract 2676: Feasible evaluation of neutron capture therapy for local recurrenced breast cancer according to boron uptake in tumour with estimating by F-BPA positron emission tomograpy
Authors: Yanagie Hironobu , Takahashi Hiroyuki , Furuya Yoshitaka , Kumada Hiroaki , Nakamura Takemi , Horiguchi Hironori , Sugiyama Hirotaka , Ono Koji , Ono Minoru , Eriguchi Masazumi 
Published: June 2012

Local recurrenced breast cancer is one of the most difficult neoplasms to cure and there is a need for new combinated therapy. If sufficient boron compound can be targeted accurate to the tumour, Boron Neutron Capture Therapy (BNCT) can be applied to local recurrenced breast cancer. We are planning BNCT to patients of local recurrenced breast cancer. In this study, we performed a feasibility thermal neutron dosimetry with JCDS at JRR4 reactor of Japan Atomic Research Institute according to boron uptake in tumour with estimating by 18F-BPA positron emission tomograpy(PET).

Recently, positron emission tomograpy is commonly used for primary detection and metastasis of cancers. In the fields of BNCT, 18F labeled borono-phenylalanine(BPA)-PET are also spread to applyed to evaluate the accumulation of boron atoms to tumours and the actibity of cancer cells. We experienced the 18F-BPA PET for the case of breast cancer patients who had metastased to right supraclaviclar lymph node. [Case] The 55 y.o. patient was performed modified radical mastectomy with lymph node dissection (Patey’ s method). After 3 years later, right cervical LN metastasis was occured, and the patients was administrated Capecitabine (2400mg/day for 21 days, and one week rest), or TS-1(tegafur, gimeracil, oteracil potassium, 100mg/ day), Herceptin(firstly 228mg, and then 114mg per week), or medroxyprogesterone(1200 mg/day). The high accumulating images of metastased to right supraclaviclar lymph node was acquired by 18F-BPA PET. The tumour / blood ratio was 2.26. There was no other active images in the body.

In case of advanced breast cancer, we performed the feasibility estimation of 3D construction of tumour according to the PET-CT imaging of a patient with epithermal neutron mode at JRR4. The thermal neutron flux was 1.145×10E+09 cm-2s-1 at the surface of 3D body images in simulation according to the CT images. The blood boron concentration (ppm) and tumour/normal tissue ratio are estimated to 24, 2.26, respectively. Tumour RBE is estimated to 3.8 Gy/h, and skin RBE is 2.5 Gy/h. Skin RBE dose is ristricted to 10 Gy-Eq, the maximum tumour RBE dose, minimum tumour RBE dose, and mean tumour RBE dose are 38.5, 19.9, and 30.6 Gy-Eq, respectively, in 40 minutes irradiation.

In this study, we showed the possibility to apply BNCT to local recurrenced advanced breast cancer with the themal neutron dosimetry for BNCT according to boron uptake in tumour with estimating by F-BPA PET. We can irradiate tumours selectively and safety as possible, reducing the effects on neighboring healthy tissues by using BNCT.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2676. doi:10.1158/1538-7445.AM2011-2676