Yoshida, C.Fletcher, L.Ohashi, K.Wakita, H.Kumagai, T.Shiseki, M.Matsuei, K.Inokuchi, K.Hatta, Y.Shirasugi, Y.Yamaguchi, T.Sakamoto, J.Branford, S.Sakamaki, H.2015-06-052015-06-052012International Journal of Clinical Oncology, 2012; 17(6):584-5891341-96251437-7772http://hdl.handle.net/2440/91910BACKGROUND: Real-time quantitative polymerase chain reaction (RQ-PCR) has been widely used for molecular monitoring for patients with chronic myeloid leukemia (CML). Currently, RQ-PCR is not based on the concept of international scale (IS) in Japan; mainly because none of the domestic laboratories have obtained their own conversion factor (CF) which makes it possible to convert locally scaled BCR-ABL (BCR-ABL (L)) value to the IS (BCR-ABL (IS)). To join the global trend of molecular assessment of BCR-ABL in CML patients, we have tried to obtain a CF in Japan. METHODS: Samples from 55 patients were exchanged between the Japanese laboratory and the reference laboratory in Adelaide, and BCR-ABL and internal control gene transcripts of the samples were measured using RQ-PCR. The patient bias conversion method was used to determine the CF for the IS using the Bland and Altman method. RESULTS: The local CF in the Japanese laboratory was determined to be 0.87. Based on this CF, 0.1% BCR-ABL (IS), defined as major molecular response, becomes equivalent to 731 copy/μg RNA BCR-ABL (L). CONCLUSION: This study is the first to introduce a laboratory-specific CF for harmonizing RQ-PCR methodology for detecting BCR-ABL transcripts to Japan, which may open new windows for molecular assessment of CML patients in Japan.en© Japan Society of Clinical Oncology 2011Chronic myeloid leukemia; BCR-ABL; Real-time quantitative PCR; International scale; Conversion factorJournal article003001838510.1007/s10147-011-0328-x0003124989000082-s2.0-84880700401115263Branford, S. [0000-0002-1964-3626] [0000-0002-5095-7981]