F-18 fluorodeoxyglucose positron emission tomography staging in radical radiotherapy candidates with nonsmall cell lung carcinoma: powerful correlation with survival and high impact on treatment.
BACKGROUND
Successful treatment of nonsmall cell lung carcinoma (NSCLC) with radical radiotherapy (RT) requires accurate delineation of tumor extent. Conventional computed tomography-based noninvasive staging often estimates intrathoracic thoracic tumor extent incorrectly and fails to detect distant metastasis. High sensitivity and specificity are reported for F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) staging in potentially resectable NSCLC. The authors investigated FDG-PET staging in radical RT candidates with unresectable NSCLC.


METHODS
The authors prospectively studied 153 consecutive patients with unresectable NSCLC who were candidates for radical RT after conventional staging and had PET scans. Patients were allocated both "before PET" and "after PET" stages. Subsequent management was recorded. Survival analysis was used to compare validity of pre-PET and post-PET staging.


RESULTS
After PET, 107 patients (70%) actually received radical therapies (radical RT with or without concurrent chemotherapy, n = 102; radical surgery, n = 5); 46 patients (30%) received palliative treatment because of PET-detected distant metastasis (n = 28; 18%) or extensive locoregional disease (n = 18; 12%). Palliative therapies were RT (n = 33), chemotherapy (n = 12), or supportive care (n = 1). All five surgically treated patients underwent potentially curative resections after downstaging by PET. For radically treated patients, post-PET stage (P = 0.0041) but not pre-PET stage (P = 0.19) was strongly associated with survival. Radically treated patients survived longer than those treated palliatively (P = 0.02; 1-year survival, 69% and 44%, respectively; 2-year survival, 44% radical; no palliative patients had 2-yr follow-up).


CONCLUSIONS
Positron emission tomography-assisted staging detected unsuspected metastasis in 20%, strongly influenced choice of treatment strategy, frequently impacted RT planning, and was a powerful predictor of survival. Potential impact of FDG-PET is even greater in radical RT candidates with NSCLC than in surgical candidates.
Mac Manus
M P
MP
Department of Radiation Oncology, Peter MacCallum Cancer Institute, A'Beckett Street, Melbourne, Victoria 3000, Australia. mmanus@petermac.unimelb.edu.au
Hicks
R J
RJ
Ball
D L
DL
Kalff
V
V
Matthews
J P
JP
Salminen
E
E
Khaw
P
P
Wirth
A
A
Rischin
D
D
McKenzie
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000532:radiotherapy* / Q000556:secondary; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D016019:Survival Analysis; D014055:Tomography, Emission-Computed
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18