Detailed dosimetry and clinical outcome analysis of the Argentine BNCT trials in cutaneous nodules melanomas.

GONZALEZ, S; CASAL, MR; SANTA CRUZ, G; BONOMI, M; JIMENEZ REBAGLIATI, R; CARANDO, DG; BLAUMANN, HR; DAGROSA, MA; LONGHINO, J; CALZETTA, O; FELD, D; CASTIGLIA, S; ROTH, BMC; MENENDEZ, P; BATISTONI, D; LIBERMAN, SJ

Takamatsu, Kagawa, Japan

Congreso; 12th International Congress on Neutron Capture Therapy; 2006

International Society for Neutron Capture Therapy

Three female patients with biopsy-proven nodular melanoma were treated to six separate sites as part of the Phase I/II BNCT clinical trial conducted at the Comisión Nacional de Energía Atómica (CNEA) and the Instituto A. Roffo, Argentina. This work reports on the detailed dosimetry for the clinical trials, and presents a preliminary analysis to investigate the possible influence of tumor size and total equivalent dose on the observed local tumor response. Also, the appropriateness of applying a 3.5 tumor-to-blood 10B concentration ratio for the BPA compound in nodular melanoma cases is discussed. The statistical analysis showed that tumor response depends not only on the dose but also, and highly, on the tumor size. For these three patients, there was no significant difference between minimum and mean equivalent doses as explicative for tumor response. The collection of sixteen experimental-based tumor-to-blood ratios determined by CNEA in nodular melanoma patients derived an average value and standard deviation of 2.5 ± 0.6. This result suggests that a lower ratio could be more suitable for estimating the clinical dosimetry. It is also consistent with the worse tumor control rate in nodular melanomas observed by other researchers.