Evaluation of 99mTc-L-methionine brain SPECT for detection of recurrent brain tumor: a pilot study with radiological and pathological correlation.
OBJECTIVE
To evaluate technetium labeled L-methionine for imaging recurrent brain tumors.


METHODS
Brain SPECT with 99mTc-L-methionine was performed to evaluate tumor viability in 42 patients with primary brain tumor. Findings of SPECT were correlated with radiological and histopathological findings as reference.


RESULTS
99mTc-L-methionine showed localized increased uptake in 40 patients with tumor recurrence, whereas 2 patients with post-radiation gliosis did not show tracer accumulation. A low differential uptake rate (DUR) 2.43 +/- 0.74 and methionine retention (MR) index 0.93 +/- 0.03 was seen in cases of post-radiation gliosis. A high DUR (36.20 +/- 10.31) and MR index (4.87 +/- 2.37) was seen in cases of recurrent tumor. Mean DUR in high-grade tumors (44.01 +/- 8.46) was significantly higher (P<0.001) than in low-grade tumors (30.42 +/- 7.38), and mean MR index in high-grade tumors (7.03 +/- 2.05) was significantly higher than in low-grade tumors (3.27 +/- 0.82) (P<0.001).


CONCLUSIONS
99mTc-L-methionine can be used as a SPECT tracer to differentiate tumor recurrence from post-radiation gliosis.
Barai
S
S
Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India. danzig@rediffmail.com
Bandopadhayaya
G P
GP
Julka
P K
PK
Kale
S S
SS
Malhotra
A
A
Haloi
A K
AK
Seith
A
A
Gopendro Sing
N
N
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging; D001932:Brain Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008715:Methionine / Q000378:metabolism; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D010865:Pilot Projects; D019275:Radiopharmaceuticals; D013667:Technetium; D015899:Tomography, Emission-Computed, Single-Photon
D019275:Radiopharmaceuticals; D013667:Technetium; D008715:Methionine