Comparing 18-fluoro-2-deoxyglucose positron emission tomography with a combination of technetium 99m tetrofosmin single photon emission computed tomography and computed tomography to detect recurrent or persistent nasopharyngeal carcinomas after radiotherapy
Ch. Kao et al., Comparing 18-fluoro-2-deoxyglucose positron emission tomography with a combination of technetium 99m tetrofosmin single photon emission computed tomography and computed tomography to detect recurrent or persistent nasopharyngeal carcinomas after radiotherapy, CANCER, 92(2), 2001, pp. 434-439
BACKGROUND, The diagnostic accuracy of combined computed tomography (CT) an
d technetium 99m tetrofosmin (Tc-TF) single photon emission computed tomogr
aphy (SPECT) of head and neck to differentiate recurrent or residual nasoph
aryngeal carcinomas (NPCs) from benign lesions after radiotherapy was evalu
ated and compared with positron emission tomography (PET) with 18-fluoro-2-
deoxyglucose (FDG).
METHODS. Four months after radiotherapy, 36 patients with NPC underwent Tc-
TF SPECT and CT of head and neck to differentiate recurrent or residual NPC
from benign lesions. Histopathologic examinations were performed on nasoph
aryngeal biopsies of all 36 patients.
RESULTS. Based on the biopsy results, the sensitivity, specificity, and acc
uracy of Tc-TF SPECT were 64%, 96%, and 86%, respectively, for differentiat
ion of recurrent or persistent NPC from benign lesions. For CT and FDG-PET,
the sensitivity, specificity, and accuracy were 73%, 88%, and 83% and 100%
, 96%, 97%, respectively. For the 27 patients with NPC whose Tc-TF SPECT an
d CT results were congruent, the combination of Tc-TF SPECT and CT had the
same sensitivity, specificity, and accuracy (100%, 96%, and 96%) as FDG-PET
. For the nine patients with NPC with incongruent Tc-TF SPECT and CT result
s, FDG-PET correctly differentiated two benign lesions from seven recurrent
/residual NPCs.
CONCLUSIONS, Although, FDG-PET is the best tool for detecting recurrent or
residual NPC, combined congruent Tc-TF SPECT and CT results achieved the sa
me accuracy as FDG-PET. Therefore, we concluded that FDG-PET could be consi
dered only when Tc-TF SPECT and CT give incongruent results. (C) 2001 Ameri
can Cancer Society.