Pre- and post-therapy thallium-201 and technetium-99m-sestamibi SPECT in nasopharyngeal carcinoma.
We prospectively studied the diagnostic potential of 201Tl and 99mTc-sestamibi (MIBI) SPECT for evaluating the extent of primary disease and differentiating residual/recurrent disease from post-therapy changes in patients with nasopharyngeal carcinoma (NPC).


METHODS
Fifty patients (20 initial presentation, 30 post-therapy evaluation) underwent 201Tl and MIBI imaging. The findings were correlated with CT/MRI results. Tumor-to-background ratios were obtained. Biopsy confirmation (14 patients) and/or 6-12 mo clinical follow-up data (16 patients) were available in the post-therapy group.


RESULTS
All primary disease sites were accurately detected by both imaging studies in the pretherapy group. However, MIBI-SPECT was superior to 201Tl SPECT (p = 0.0057) in detecting regional metastases (sensitivities of 95% versus 68%). In the post-therapy group, MIBI and 201Tl imaging were true-positive in 14 of 16 patients with proven residual/recurrent. In 17 patients who had no evidence of residual/recurrent tumor. CT/MRI was false-positive in 13 when MIBI and 201Tl imaging were true-negative in 10 and false positive in 3. MIBI, 201Tl and CT/MRI had sensitivities of 87.5%, 87.5%, 100%, specificities of 82.4%, 76.5%, 23.5% and accuracies of 85%, 82%, 61%, respectively. Tumor-to-background ratios were < or = 1.5 in all false-positive cases except one.


CONCLUSIONS
MIBI-SPECT proves more accurate than 201Tl SPECT in detecting regional metastases at initial presentation. MIBI and 201Tl imaging have higher specificity and accuracy than CT/MRI and MIBI-SPECT is slightly more specific than 201Tl SPECT in differentiating residual/ recurrent disease from post-therapy changes in patients with NPC.
Kostakoglu
L
L
Department of Nuclear Medicine, Hacettepe University Medical Center, Ankara, Turkey.
Uysal
U
U
Ozyar
E
E
Elahi
N
N
Hayran
M
M
Uzal
D
D
Demirkazik
F B
FB
Kars
A
A
Uğur
O
O
Atahan
L
L
Bekdik
C F
CF
D000293:Adolescent; D000328:Adult; D000368:Aged; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000000981:diagnostic imaging* / Q000628:therapy; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D018365:Neoplasm, Residual; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon
D013794:Thallium Radioisotopes; D017256:Technetium Tc 99m Sestamibi