Prognostic value of post-treatment metabolic tumor volume from11C-methionine PET/CT in recurrent malignant glioma.
We investigated the diagnostic and prognostic significance of metabolic parameters from11C-methionine (MET) positron emission tomography (PET) in patients with malignant glioma. The MET-PET was examined in 42 patients who had been previously treated with adjuvant treatment for malignant glioma. Both ratios of maximal MET uptake of the tumors to those of the contralateral normal gray matter (T/N ratio) and metabolic tumor volume (MTV) were estimated in each lesion. The diagnostic performance for recurrence was investigated in all enrolled patients. A definitive diagnosis was done with pathologic confirmation or clinical follow-up. Among recurrent patients, we evaluated the prognostic value of metabolic parameters (T/N ratio and MTV) as well as clinical factors. Among 42 patients, 35 patients were revealed with recurrence. Both T/N ratios (p = 0.009) and MTV (p = 0.001) exhibited statistical significance to differentiate between recurrence and post-treatment radiation effect. A T/N ratio of 1.43 provided the best sensitivity and specificity for recurrence (91.4 and 100 %, respectively), and a MTV of 6.72 cm3provided the best sensitivity and specificity (77.1 % and 100 %, respectively). To evaluate the prognostic impact, different cutoffs of MTV were examined in patients with recurrent tumor and a threshold of 60 cm3was determined as a best cutoff value to separate the patients in two prognostic groups. Univariate analysis revealed improved overall survival (OS) for patients with Karnofsky performance scale (KPS) score ≥70 (p < 0.001) or MTV <60 cm3(p = 0.049). Multivariate analysis showed that patients with KPS score ≥70 (p < 0.001; hazard ratio = 0.104; 95 % CI, 0.029-0.371) or MTV < 60 cm3(p = 0.031; hazard ratio = 0.288; 95 % CI, 0.093-0.895) were significantly associated with a longer OS. However, T/N ratio was not correlated with patients' outcome. Metabolic parameters had the diagnostic value to differentiate recurrence from post-treatment radiation effect. Compared with T/N ratio, MTV was an independent significant prognostic factor with KPS score in patients with recurrent tumor. Our study had a potential to manage these patients according to prognostic information using MET-PET.
Department of Neurosurgery, Chonnam National University Hwasun Hospital and Medical School, 160, Ilsim-ri, Hwasun-eup, Hwasun-gun, Jeollanam-do, 519-809, Republic of Korea.
Tae-Young
TY
Jung
Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, 160, Ilsim-ri, Hwasun-eup, Hwasun-gun, Jeollanam-do, 519-809, Republic of Korea.
Jung-Joon
JJ
Min
Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, 160, Ilsim-ri, Hwasun-eup, Hwasun-gun, Jeollanam-do, 519-809, Republic of Korea.
Hee-Seung
HS
Bom
Department of Neurosurgery, Chonnam National University Hwasun Hospital and Medical School, 160, Ilsim-ri, Hwasun-eup, Hwasun-gun, Jeollanam-do, 519-809, Republic of Korea.
Shin
S
Jung
Department of Neurosurgery, Chonnam National University Hwasun Hospital and Medical School, 160, Ilsim-ri, Hwasun-eup, Hwasun-gun, Jeollanam-do, 519-809, Republic of Korea.
In-Young
IY
Kim
Department of Neurosurgery, Chonnam National University Hwasun Hospital and Medical School, 160, Ilsim-ri, Hwasun-eup, Hwasun-gun, Jeollanam-do, 519-809, Republic of Korea.
Sa-Hoe
SH
Lim
Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, 160, Ilsim-ri, Hwasun-eup, Hwasun-gun, Jeollanam-do, 519-809, Republic of Korea.
Dong-Yeon
DY
Kim
Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, 160, Ilsim-ri, Hwasun-eup, Hwasun-gun, Jeollanam-do, 519-809, Republic of Korea. suninocean@hanmail.net.
Seong Young
SY
Kwon
D000293:Adolescent; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging*; D002250:Carbon Radioisotopes / Q000008:administration & dosage; D005260:Female; D005910:Glioma / Q000175:diagnosis / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008715:Methionine / Q000008:administration & dosage; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis / Q000000981:diagnostic imaging*; D000072078:Positron Emission Tomography Computed Tomography; D011379:Prognosis; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D012189:Retrospective Studies; D047368:Tumor Burden; D055815:Young Adult
D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals; D008715:Methionine
11C-methionine; Metabolic tumor volume; PET; Prognosis; Recurrence