Comparative study of Tc-99m MIBI and TI-201 SPECT in predicting chemotherapeutic response in non-small-cell lung cancer.
OBJECTIVE
Tc-99m MIBI can be excluded from cytosol against its concentration gradient as a suitable transport substrate by P-glycoprotein. Tc-99m MIBI has also been shown to be more effective than TI-201 chloride for evaluating the response to chemotherapy in patients with small-cell lung cancer. The relation between Tc-99m MIBI accumulation by the tumor and its response to chemotherapy were evaluated in patients with non-small-cell lung cancer (NSCLC) and compared with the same parameters achieved using TI-201 chloride.


METHODS
Thirty-eight patients with NSCLC were examined before chemotherapy was begun. They were classified according to the results of a follow-up computed tomogram into two groups: responders were patients in whom there was a > or =50% decrease and nonresponders were patients in whom there was a <50% decrease in the sum of the product of the maximum perpendicular diameters of all measurable lesions. All patients underwent dual-isotope imaging with TI-201 chloride and Tc-99m MIBI just before chemotherapy. Regions of interest were placed over the tumor uptake (T) and contralateral normal lung tissue (N) areas on one coronal view with a clearly defined lesion, and the T:N ratio and retention index were calculated.


RESULTS
The delayed T:N ratio and retention index for Tc-99m MIBI in the responder group were significantly greater (P<0.05) than those in the nonresponder group. There was no significant correlation between the T:N ratio and retention index and tumor response using TI-201 chloride.


CONCLUSIONS
Tc-99m MIBI SPECT may be more effective than TI-201 chloride SPECT for evaluating the response to chemotherapy in patients with NSCLC.
Nishiyama
Y
Y
Department of Radiology, Kagawa Medical University, Japan. nisiyosi@kms.ac.jp
Yamamoto
Y
Y
Satoh
K
K
Ohkawa
M
M
Kameyama
K
K
Hayashi
E
E
Fujita
J
J
Tanabe
M
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000188:drug therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome
D013794:Thallium Radioisotopes; D017256:Technetium Tc 99m Sestamibi