[Lung nodule detection with ultra-low-dose CT in routine follow-up of cancer patients].
OBJECTIVE
To evaluate the value of an ultra-low-dose CT protocol (ULD-CT) in the dectection of lungnodules in follow-up of cancer patients.


METHODS
Between April and August 2003, 72 consecutive patients with a history of malignancy were prospectively examined on a single-slice helical CT scanner (Aquilion, Toshiba) with ULD-CT (120 kV, 5 mAs, D-eff 0.12 mSv) and regular-dose CT (R-CT) (120 kV, 150 mAs, D-eff 4.8 mSv). The ULD-CT examinations were independently evaluated by two radiologists. Afterwards, consensus reading of the ULD-CT and R-CT examinations was done. Individual nodules were classified benign (benign calcifications) and non-benign. The studies were classified in 4 subgroups: 1) non-benign nodule evident; 2) non-benign nodule probable; 3) non-benign nodule possible, but not likely; 4) no-non benign nodule.


RESULTS
ULD-CT detected 180 nodules in 47 patients, while R-CT showed 168 nodules in 39 patients. The sensitivity of ULD-CT was 87 % in detecting nodules regardless of size and 94 % in detecting nodules > or = 5 mm. Regarding the prediction of a case with non-benign nodules (subgroups 1 to 3), the sensitivity of ULD-CT was 94 % and the specificity 75 %.


CONCLUSIONS
ULD-CT is a good diagnostic tool in detecting lung nodules > or = 5 mm. Radiation dose can be markedly reduced. A negative ULD-CT study excludes non-benign nodules in R-CT with a high probability. In case of a positive ULD-CT, R-CT can be immediately followed.
Gergely
I
I
Röntgenabteilung, Krankenhaus der Barmherzigen Brüder, Eisenstadt, Osterreich.
Neumann
C
C
Reiger
F
F
Dorffner
R
R
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*