Am. Ragheb et al., A COMPARATIVE-STUDY BETWEEN PLANAR GA-67, TI-201 IMAGES, CHEST-X-RAY,AND X-RAY CT IN INOPERABLE NONSMALL CELL-CARCINOMA OF THE LUNG, Clinical nuclear medicine, 20(5), 1995, pp. 426-433
Seventy patients with newly diagnosed, pathologically proven inoperabl
e non-small cell lung cancer (NSCLC) had planar Ga-67, TI-201, chest x
-ray, and chest CT imaging performed, Tumor/Normal tissue background (
T/B) ratio was calculated for 62 Ga-67 and 55 TI-201 scintigraphy stud
ies and comparisons were made between Ga-67 and TI-201 imaging results
regarding T/B ratios, site of lesion, and histologic type. The impact
of the images on the initial knowledge of the extent of the tumor and
on the radiotherapy (RT) planning was evaluated for each patient. For
primary lesions, Ga-67 imaging results were positive in 94% (66 of 70
patients) versus 71% (50 of 70 patients) for TI-201 scans (P < 0.005)
and the T/B ratio was >1.5 in 74% (46 of 62 patients) for Ga-67 versu
s 36% (20 of 55 patients) for TI-201 (P < 0.0001). For centrally locat
ed lesions, sensitivity for Ga-67 was 100% (53 of 53 patients) versus
74% (39 of 53 patients) for TI-201 (P < 0.0005) and the T/B ratio >1.5
in 84% (38 of 45 patients) for Ga-67 versus 38% (15 of 40 patients) f
or TI-201 (P > 0.001). For peripheral lesions, sensitivity of Ga-67 wa
s 76% (13 of 17 patients) versus 64% (11 of 17) for TI-201 (P > 0.05)
and the T/B ratio was >1.5 in 47% (8 of 17 patients) for Ga-67 versus
33% (5 of 15 patients) for TI-201 (P < 0.05). The sensitivity of Ga-67
for squamous cell carcinoma was 92% (37 of 40 patients) versus 75% (3
0 of 40 patients) for TI-201 (P < 0.05). For adenocarcinoma Ga-67 sens
itivity was 94% (15 of 16 patients) versus 69% (11 of 16 patients) for
TI-201 (P < 0.05). For undifferentiated carcinoma, Ga-67 sensitivity
was 100% (14 of 14 patients) versus 64% (9 of 14 patients) for TI-201
(P > 0.005). Mediastinal involvement as assessed by CT, Ga-67, and TI-
201 was present in 89%, 51%, and 10%, respectively (P < 0.0001). For d
etermination of the local extent of the tumor compared to the chest x-
ray, Ga-67 scintigraphy added more information in 49% (34 of 70 patien
ts) versus 27% (19 of 70 patients) for TI-201 (P < 0.005). When compar
ed to CT, Ga-67 scintigraphy gave additional information in 4% (3 of 7
0 patients) of the patients versus 3% (2 of 70 patients) for TI-201 im
aging. For the purpose of radiation therapy planning, if based on ches
t x-ray findings, Ga-67 scintigraphy was necessary for proper planning
in 54% (38 of 70 patients) versus 27% (19 of 70 patients) for TI-201
imaging. If treatment planning was based on CT, Ga-67 scintigraphy add
ed more Information in 19% (13 of 70 patients) versus only 3% (2 of 70
patients) for TI-201 imaging. We conclude that Ga-67 scintigraphy is
more useful than TI-201 imaging In the initial evaluation of NSCLC, Bo
th are inferior to x-ray CT imaging for staging purposes and determini
ng the local extent of the disease. Gallium-67 scintigraphy was necess
ary in some patients for proper radiation therapy treatment planning a
nd adds more useful information to the x-ray CT imaging. Thallium-201
imaging did not add more information to Ga-67 scintigraphy in any pati
ent.