The utility of 18F-fluorodeoxyglucose positron emission tomography for early diagnosis of radiation-induced myocardial damage.
OBJECTIVE
We evaluated the clinical significance of focal increased uptake in the basal myocardium on F-fluorodeoxyglucose positron emission tomography (FDG-PET) in patients with esophageal cancer after radiotherapy.


METHODS
Between August 2004 and July 2005, a total of 64 patients who had been irradiated for thoracic esophageal cancer underwent FDG-PET at least three months after the completion of chemoradiotherapy. Some patients showed increased FDG uptake in the basal portion of the myocardium. To clarify the clinical significance of these findings, further examinations of hearts were performed. The dose distribution in the myocardium with high FDG uptake was also analyzed retrospectively.


RESULTS
Thirteen (20.3%) of the 64 patients showed high FDG uptake in the basal myocardium corresponding to the irradiated fields compared with FDG uptake in the myocardium outside the irradiated fields. Eight of the 13 patients consented to undergo examinations of the heart. Five of those eight patients showed low 123I-BMIPP uptake and four showed low 201TlCl uptake in the myocardium corresponding with high FDG uptake regions. In two patients, delayed enhancement was found in some parts of the area with high FDG uptake on Gd-DTPA magnetic resonance imaging (MRI), and the delay-enhanced lesion showed hypokinesia on cine-MRI in one patient.


CONCLUSIONS
FDG-PET often shows focal increased uptake in the basal myocardium after radiotherapy for esophageal cancer. This finding indicates the possibility of radiation-induced cardiac damage, and cardiac function and symptoms of such patients should be followed carefully.
Jingu
Keiichi
K
Department of Therapeutic Radiology, Tohoku University School of Medicine, Sendai, Japan. kjingu-jr@rad.med.tohoku.ac.jp
Kaneta
Tomohiro
T
Nemoto
Kenji
K
Ichinose
Azusa
A
Oikawa
Minako
M
Takai
Yoshihiro
Y
Ogawa
Yoshihiro
Y
Nakata
Eiko
E
Sakayauchi
Toru
T
Takai
Kenji
K
Sugawara
Toshiyuki
T
Narazaki
Kakutaro
K
Fukuda
Hiroshi
H
Takahashi
Shoki
S
Yamada
Shogo
S
D000368:Aged; D000369:Aged, 80 and over; D042241:Early Diagnosis; D004938:Esophageal Neoplasms / Q000532:radiotherapy; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D005500:Follow-Up Studies; D006321:Heart / Q000000981:diagnostic imaging / Q000528:radiation effects*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D049268:Positron-Emission Tomography; D011832:Radiation Injuries / Q000175:diagnosis / Q000000981:diagnostic imaging*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18