Evaluation of the treatment response of lung cancer with positron emission tomography and L-[methyl-11C]methionine: a preliminary study.
We carried out a study to evaluate treatment response and residual mass in lung cancer with positron emission tomography (PET), using L-[methyl-11C]methionine (MET). MET tumour uptake and tumour volume measured by computed tomography (CT) before and within 2 weeks after radiotherapy or chemoradiotherapy were compared in 43 studies of 21 patients. Ten patients with local control (no recurrence) of tumour showed a larger decrease in MET uptake (65.2% +/- 12.2%) than in tumour volume (50.8% +/- 9.6%, P < 0.01). Five patients with early recurrence (from 1 to 4 months) showed smaller decreases in both MET uptake (22.2% +/- 13.5%) and tumour volume (28.6% +/- 20.0%) than those in the no-recurrence group (P < 0.01). Four patients with late recurrence (after 11 months or more) showed a similar decrease to the no-recurrence group in MET uptake (72.8% +/- 14.8%) but little change in tumour volume (18.5% +/- 19.0%), the latter result corresponding to that in the early-recurrence group. Using tumour volume only, the no-recurrence group was differentiated from both the early- and the late-recurrence group (P < 0.01), but the early-recurrence group was not differentiated from the late-recurrence group. Using the MET uptake data, the early-recurrence group was clearly distinguished from the late-recurrence group (P < 0.01), but the late-recurrence group was indistinguishable from the no-recurrence group. CT was useful in distinguishing the no-recurrence group from the groups in which there was ultimate recurrence, whether early or late. When a residual mass is seen on CT, PET seems to be helpful in evaluating tumour viability.
Department of Radiology and Nuclear Medicine, Tohoku University, Sendai, Japan.
K
K
Kubota
S
S
Yamada
K
K
Ishiwata
M
M
Ito
T
T
Fujiwara
H
H
Fukuda
M
M
Tada
T
T
Ido
D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000628:therapy; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002250:Carbon Radioisotopes; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000628:therapy; D018288:Carcinoma, Small Cell / Q000000981:diagnostic imaging / Q000628:therapy; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000628:therapy*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000628:therapy*; D008297:Male; D008715:Methionine / Q000031:analogs & derivatives*; D008875:Middle Aged; D014055:Tomography, Emission-Computed; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D002250:Carbon Radioisotopes; D008715:Methionine; C038344:methionine methyl ester