Is pre-therapeutical FDG-PET/CT capable to detect high risk tumor subvolumes responsible for local failure in non-small cell lung cancer?
OBJECTIVE
Local failure is a significant issue following radiotherapy (RT) for patients with non-small cell lung cancer (NSCLC). The aim of this study was to find out whether FDG-PET/CT is capable to predict tumor relapse location in patients with NSCLC, in particular to determine high risk tumors' subvolumes responsible for local failure.


METHODS
Ten patients with locoregional relapse of NSCLC underwent FDG-PET/CT before, during, and in the 4-12 months following curative chemoradiotherapy (ChRT, 66 Gy) using a combined PET/CT scanner. Morphologic and metabolic tumor volumetry and an evaluation of FDG-uptake dynamics were performed.


RESULTS
CT showed partial reduction of tumor volume after RT in all patients. PET-revealed partial in eight patients and complete metabolic response in two patients during RT. Six to nine months after RT, local failure was diagnosed in all patients with both methods. Tumor recurrences were localized mostly in the most active ones of pre-therapeutically metabolic regions of the primary tumor.


CONCLUSIONS
Local failure in NSCLC appears most common at the primary site and within the irradiated target volume with the highest FDG uptake. This observation may be useful for further optimization of radiotherapy of NSCLC, for example, by the application of additional radiation dose to subvolumes of primary tumors with higher FDG uptake.
Abramyuk
Andrij
A
OncoRay, Center for Radiation Research in Oncology, TU, Dresden, Germany. Andrij.Abramyuk@OncoRay.de
Tokalov
Sergey
S
Zöphel
Klaus
K
Koch
Arne
A
Szluha Lazanyi
Kornelia
K
Gillham
Charles
C
Herrmann
Thomas
T
Abolmaali
Nasreddin
N
D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D015996:Survival Rate; D014055:Tomography, Emission-Computed / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D047368:Tumor Burden
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18