Dynamic scintigraphy with thallium-201 chloride (Tl-201) for the diagnosis of tumors of the head and neck.
OBJECTIVE
The purpose of this study was to differentiate between malignant tumors and benign tumors of the head and neck by means of thallium-201 chloride scintigraphy.


METHODS
Thallium-201 chloride (Tl-201) scintigraphy and Ga-67 citrate (Ga-67) scintigraphy were performed in 10 patients with a benign tumor and in 90 patients with a malignant tumor. The blood flow index and the tumor retention index were obtained by means of Tl-201 scintigraphy. The blood flow index = the count of tumor/the count of control in the early dynamic scan from 30 to 120 seconds after injection, and the tumor retention index = (the count of tumor/the count of control in the delayed dynamic scan 2.5 hours after injection)/(the count of tumor/the count of control in the early dynamic scan from 4 to 5 minutes after injection).


RESULTS
The early and delayed scans with Tl-201 demonstrated a very high correlation with the blood flow index. The tumor retention index had a tendency to increase in malignant tumors, especially in the poorly differentiated tumors and the severely invasive tumors. Likewise, the tumor retention index decreased in benign tumors. These results proved to be statistically significant, and in turn Tl-201 scintigraphy was deemed superior to Ga-67 scintigraphy. Tl-201 scintigraphy was also useful in detecting small-size tumors.


CONCLUSIONS
The tumor retention index of Tl-201 was useful for the differentiation of malignant tumors of the head and neck from benign tumors of the same areas.
Sato
T
T
Department of Dental Radiology, Kagoshima University Dental School, Japan. sato@dental.hal.kagoshima-u.ac.jp
Indo
H
H
Kawabata
Y
Y
Iwashita
Y
Y
Morita
Y
Y
Noikura
T
T
Sugihara
K
K
Mimura
T
T
D000230:Adenocarcinoma / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology; D000235:Adenolymphoma / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology; D008949:Adenoma, Pleomorphic / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology; D016009:Chi-Square Distribution; D002951:Citrates; D005260:Female; D005708:Gallium; D005710:Gallium Radioisotopes; D006258:Head and Neck Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008297:Male; D008441:Maxillary Neoplasms / Q000000981:diagnostic imaging; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010307:Parotid Neoplasms / Q000000981:diagnostic imaging; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012039:Regional Blood Flow / Q000502:physiology; D012588:Scintillation Counting / Q000379:methods; D013223:Statistics as Topic; D013793:Thallium; D013794:Thallium Radioisotopes; D013997:Time Factors
D002951:Citrates; D005710:Gallium Radioisotopes; D019275:Radiopharmaceuticals; D013794:Thallium Radioisotopes; C027549:thallium chloride; D013793:Thallium; D005708:Gallium; C103850:gallium citrate