TL-201 UPTAKE, HISTOPATHOLOGICAL DIFFERENTIATION AND NA-K ATPASE IN LUNG ADENOCARCINOMA

To clarify differences in accumulation in Tl-201 scintigraphy, we exam ined the relationship between uptake of Tl-201, histopathological diff erentiation and Na-K ATPase. Methods: Thallium-201 SPECT was performed twice: 15 min (early scan) and 120 min (delayed scan) after intraveno us injection of 3 mCi Tl-201-chloride. The uptake ratio of Tl-201 was calculated and compared with the grade of differentiation and the stai ning pattern of Na-K ATPase. Results: The sensitivity of Tl-201 SPECT for well-differentiated adenocarcinomas was lower than that for modera tely and poorly differentiated ones. The uptake ratio on the delayed s can was significantly lower in the well-differentiated group than that in the moderately and poorly differentiated groups. This parameter wa s also significantly higher in the Na-K ATPase-positive group than the -negative group. Conclusions: These results indicate that the uptake ratio of Tl-201 SPECT may be a noninvasive indicator of the grade of p athological differentiation of adenocarcinoma and provide insight into the relationship among Tl-201 SPECT, malignancy and Na-K ATPase.