title: (18)FDG-PET at 1-Month Intervals Is a Better Predictive Marker for GISTs That Are Difficult to Be Diagnosed Histopathologically: A Case Report.
abstract: Imatinib mesylate is a tyrosine kinase inhibitor of c-KIT and PDGFRA. Imatinib mesylate is an effective drug that can be used as a first-choice agent for treatment of GISTs. Prior to treatment, molecular diagnosis of c-KIT or PDGFRA is necessary; however, in some types of GISTs, it is impossible to obtain a sufficient amount of specimen for diagnosis. An inoperable or marginally resectable GIST in a 79-year-old female was difficult to be diagnosed at a molecular pathological level, and hence, exploratory treatment was initiated using imatinib combined with (18)FDG-PET evaluation at 1-month intervals. PET imaging indicated a positive response, and so we continued imatinib treatment in an NAC setting for 4 months. As a result, curative resection of the entire tumor was successfully performed with organ preservation and minimally invasive surgery. (18)FDG-PET evaluation at 1-month intervals is beneficial for GISTs that are difficult to be diagnosed histopathologically.
authors.affiliation: Department of Clinical Oncology, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Otsuka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Takahashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nanjo
authors.forename: Hideaki
authors.initials: H
authors.lastname: Miyazawa
authors.forename: Masatake
authors.initials: M
authors.lastname: Iida
authors.forename: Yuki
authors.initials: Y
authors.lastname: Abe
authors.forename: Mario
authors.initials: M
authors.lastname: Jin
authors.forename: Hirohide
authors.initials: H
authors.lastname: Onishi
authors.forename: Manabu
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shibata