Comparison of super(201)Tl-chloride SPECT with super(99m)Tc-MIBI SPECT in the depiction of malignant head and neck tumors

• Published in: Annals of nuclear medicine 2006-02, Vol.20 (2), p.107-114
• Main Authors: Tomura, Noriaki, Watanabe, Osamu, Takahashi, Satoshi, Sakuma, Ikuo, Otani, Takahiro, Nishii, Toshiaki, Watarai, Jiro
• Format: Article
• Language: English
• ISSN: 0914-7187; 1864-6433
• DOI: 10.1007/BF02985622

Objective: Comparison of super(201)T1 chloride SPECT (Tl-SPECT) with super(99m)Tc-MIBI SPECT (MIBI-SPECT) in the depiction of malignant head and neck tumors was prospectively studied. Methods: Forty-one patients with various tumors of the head and neck were included in this prospective study. Histologically, 36 patients had squamous cell carcinomas, 3 undifferentiated carcinomas, 1 transitional cell carcinoma, and 1 MALT lymphoma. All patients underwent a simultaneous dual-isotope SPECT of the head and neck with super(201)Tl and super(99m)Tc-MIBI. Dual-isotope SPECT for early (n = 41) and delayed acquisition (n = 21) was performed. Qualitatively, 3 observers evaluated both Tl-SPECT and MIBI-SPECT individually. The interpretation criteria were graded as grade 1 (no abnormal increased uptake) to 5 (definitely increased uptake of a degree equal to or greater than that of normal salivary gland). Statistical analysis of the comparison of Tl-SPECT and MIBI-SPECT was performed. The interobserver difference was evaluated using the -coefficient. Quantitatively, T/N ratio (the ratio of the counts in the tumor divided by that in the normal nuchal muscles) and retention index were compared between Tl-SPECT and MIBI-SPECT. Results: On both the early and delayed images, the grades of uptake of the tumor in Tl-SPECT were significantly higher than those in MIBI-SPECT by three observers. The grade of T1-uptake of the tumor on the delayed images was 5 for all observers (-coefficient =1); however, the -coefficient varied from 0.39 to 0.84 in early Tl-SPECT, and in early and delayed MIBI-SPECT. Statistical differences in T/N ratio were noted between early Tl-SPECT (2.87 plus or minus 1.19) and MIBI-SPECT (2.48 plus or minus 1.06), and between delayed Tl-SPECT (2.11 plus or minus 0.70) and MIBI-SPECT ( 1.20 plus or minus 0.48). The retention index of Tl-SPECT (0.81 plus or minus 0.24) was significantly higher than that of MIBI-SPECT (0.52 plus or minus 0.15). Conclusions: The present study qualitatively and quantitatively showed that super(201)T1 had higher accumulation in the tumor than super(99m)Tc-MIBI in both early and delayed images.