Discordant Tl-201 and Tc-99m imaging in a patient with thyroid carcinoma and Hashimoto's disease

In a case of Hashimoto's disease complicated by thyroid gland cancer, the primary site of the cancer was visualized as a cold nodule on Tc-99m pertechnetate scintigraphy, as a warm nodule on Tl-201 early imaging, and as a hot nodule on Tl-201 delayed imaging. Generally, Tl-201 shows markedly diffuse accumulation in the lesions of Hashimoto's disease. The warm nodules observed on early scans suggested similar accumulation at the sites of Hashimoto's disease and thyroid cancer. The hot nodules on delayed imaging may be due to the difference in Tl-201 washout time between the sites of Hashimoto's disease and thyroid cancer. There was markedly increased Tl-201 accumulation in bilateral cervical metastatic lymph nodes on both early and delayed images.     

Visualization of nasopharyngeal carcinoma with Tl-201 chloride and a three-head rotating gamma camera SPECT system

Tl-201 SPECT was performed on 12 patients with Nasopharyngeal carcinoma (NPC) by means of a three-head rotating gamma camera to evaluate whether or not Tl-201 SPECT was useful and reliable for assessing the tumor viability of NPC. Tl-201 clearly accumulated in the tumor in 3 patients before radiation treatment and increased Tl-201 uptake by the lesion ceased after the treatment. Three of 9 patients who were followed up after radiotherapy developed apparent local recurrence and Tl-201 SPECT clearly visualized these recurrent lesions. Tl-201 SPECT was very useful for assessing the tumor response to irradiation and for detecting local recurrent tumor. A High resolution SPECT system employing Tl-201 chloride is a new reliable and accurate diagnostic tool for the assessment of NPC.     

Tl-201 uptake and retention in a Warthin’s tumor

We report scan findings of Tl-201 in a case of histologically proved Warthin’s tumor. Dual isotopes acquisition was performed in a case of left parotid Warthin’ s tumor. Both early and delayed Tc-99m-pertechnetate (Tc-99m) images showed increased uptake at the tumor. Tl-201 scan also showed an increase of uptake on the early image and retention on the delayed image. The uptake ratios of Tl-201 were 3.0 (early) and 2.3 (delayed). Scan findings of Tl-201 in a case of Warthin’s tumor were similar to those of Tc-99m, and the interpretation of Tl-201 images should be accompanied with Tc-99m images.     

Thallium-201 chloride (Tl-201) accumulation and Na+/K+-ATPase expression in tumours of the head and neck

OBJECTIVES: The purpose of this report was to evaluate the relationship between the tumour retention index of thallium-201 chloride (Tl-201) scintigraphy and the Na+/K+-ATPase expression in tumours of the head and neck. METHODS: Tl-201 scintigraphy was performed in 146 patients (129 with malignant tumours, ten with benign tumours and seven with inflammation). The tumour retention index was obtained from the early and delayed dynamic Tl-201 scans. The Na+/K+-ATPase expression was evaluated immunohistochemically in 61 of 129 patients with malignant tumour. Furthermore, another 22 patients with benign tumour were evaluated immunohistochemically as a benign control. Comparison of the correlations between the grade of histopathological differentiation of tumour, the tumour retention index of Tl-201 scintigraphy and the Na+/K+-ATPase expression was performed. RESULTS: The grade of histopathological differentiation of tumour, the tumour retention index of Tl-201 scintigraphy and the expression of Na+/K+-ATPase showed a good correlation indicating that Na+/K+-ATPase plays an important role in transportation for Tl-201 to go through the tumour cell membrane. CONCLUSIONS: Na+/K+-ATPase is one of the most important factors for Tl-201 accumulation in tumour.     

Tl-201 chloride and Tc-99m MIBI accumulation in lung adenocarcinoma in patients with and without distant metastases

PURPOSE: The relation between Tl-201 chloride accumulation by the tumor and its distant metastatic potential were evaluated in patients with lung adenocarcinoma and compared with the same parameters achieved using Tc-99m MIBI. METHODS: Fifty-six patients with primary lung adenocarcinoma were examined before therapy was begun. They were classified according to the radiologic findings and pathologic diagnosis into two groups: distant metastases and no distant metastases. All patients underwent dual-isotope imaging with Tl-201 chloride and Tc-99m MIBI. Regions of interest were placed over the tumor uptake (T) and contralateral normal lung tissue (N) areas on one transverse view with clearly defined lesions, and the T:N ratio and retention index were calculated. RESULTS: The early and delayed T:N ratios and retention index using Tl-201 chloride SPECT in the distant-metastases group were significantly greater (P < 0.001 to P < 0.05) than were those in the no-distant-metastases group. There was no significant correlation between the T:N ratio and retention index and distant metastatic potential using Tc-99m MIBI SPECT. CONCLUSION: Tl-201 chloride SPECT may be more effective than Tc-99m MIBI SPECT for evaluating the distant metastatic potential of primary lung adenocarcinoma.     

Tl-201 and Ga-67 scintigraphy in non-Hodgkin's lymphoma.

Ga-67 scintigraphy is routinely used to stage and monitor non-Hodgkin's lymphoma (NHL). It is highly sensitive in high-grade NHL but less so in intermediate- and low-grade NHL. Several studies have reported the use of Tl-201 in the low and intermediate grades of NHL and found it superior in low-grade NHL. In this study, the authors evaluated the utility of combined Ga-67 and Tl-201 scintigraphy in low, intermediate, and unusual types of NHL. Combined Tl-201 and Ga-67 scintigraphy were done in 33 patients (18 women, 15 men; age range, 21-91 years; mean age, 56 years). Tl-201 and Ga-67 had similar overall patient sensitivity in the 33 patients studied. However, the use of both agents increased the overall patient sensitivity from 67% (for Ga-67 only) to 82% and improved the overall site detection from 59 positive sites with Ga-67 to 81 abnormal sites with both Tl-201 and Ga-67. The combined use of Tl-201 and Ga-67 scintigraphy in low- and intermediate-grade NHL resulted in increased disease and site detection and is beneficial for clinical follow-up.     

Bone and Tl-201 scintigraphy in a case of hereditary multiple exostoses.

A 17-year-old girl with hereditary multiple exostoses, who was thought to have malignant transformation of an exostotic lesion, was examined by bone and Tl-201 chloride scintigraphy. Scintigraphy showed markedly intense uptake by the lesion, whereas Tl-201 imaging did not. Bone scintigraphy revealed intense to moderate uptake in other exostotic lesions, but none was apparent on the Tl-201 study. The lesion was resected and the histopathologic diagnosis was osteochondroma. Negative findings of Tl-201 scintigraphy may not exclude the possibility of chondrosarcoma, and the utility of this method may be limited. However, Tl-201 scintigraphy appears to have a useful role in differentiating malignant transformation from benign osteochondroma in hereditary multiple exostoses.     

Increased accumulation of Tl-201 in monostotic Paget's disease of the patella: evaluation with quantitative analysis.

Monostotic Paget's disease of the patella was detected with Tc-99m MDP and Tl-201 scans. Diffuse intense uptake of MDP in the left patella was observed on the blood-pool and late phases of the bone scan. Tl-201 imaging was performed to differentiate a malignant process and showed diffuse marked accumulation at the same site. Semiquantitative analysis of the patella region on both Tc-99m MDP and Tl-201 scans did not support a diagnosis of cancer. Radiographs showed the features of Paget's disease of the bone. Findings of a pathologic evaluation were compatible with the diagnosis of osteitis deformans. This case represents the unusual skeletal involvement of monostotic Paget's disease of the bone in the patella. Tl-201 accumulation in the Paget's lesion was suggested to be caused by increased metabolic activity of the lesion but was not indicative of a malignant process.