Proton NMR relaxation times of experimental Lewis lung carcinoma after irradiation.
NMR proton spin-lattice (T1) and spin-spin (T2) relaxation times were measured ex vivo on Lewis lung carcinoma after in vivo single irradiation with an absorbed dose of 4 Gy. The results were compared to tumoural volume evolution, pathological examinations, and cell kinetic measurements. Tumour growth decreased between the third and the sixth day after irradiation while relaxation times, especially T1, is increased 2 days before the clinical recurrence of the tumour is observed. Pathological morphometric measurements tempted to show that necrosis is less extended after irradiation. Cell cycle analysis demonstrated the G2/M phase blockade by radiation after one day, and its release 4 days later. These phenomena could be important for in vivo radiotherapy follow-up using determination of relaxation times by magnetic resonance imaging (MRI).
Le Moyec
L
L
NMR Laboratory, Faculté de Médecine, Rennes, France.
Pellen
P
P
Merdrignac-Le Noan
G
G
Le Lan
J
J
Lancien
G
G
Chenal
C
C
de Certaines
J D
JD
D000818:Animals; D002455:Cell Division; D003037:Cobalt Radioisotopes / Q000627:therapeutic use; D005434:Flow Cytometry; D008175:Lung Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D009368:Neoplasm Transplantation; D013997:Time Factors
D003037:Cobalt Radioisotopes