Scintigraphic prediction of resistance to radiation and chemotherapy in patients with lung carcinoma: technetium 99m-tetrofosmin and thallium-201 dual single photon emission computed tomography study.

BACKGROUND: Various prognostic markers for lung carcinoma have been proposed, but to the authors' knowledge none is noninvasive and convenient for clinical use. The current study examined the utility of several radiotracers for the prediction of multidrug resistance (MDR) and radioresistance in patients with lung carcinoma. METHODS: Thirty patients with untreated lung carcinoma underwent a dual isotope single photon emission computed tomography (SPECT) scan at 10 minutes and 120 minutes after the injection of technetium-99m ((99m)Tc)-tetrofosmin ((99m)Tc-TF) (370 megabecquerels [MBq]) and thallium-201 ((201)TlCl) (111 MBq). Retention of each tracer was evaluated semiquantitatively. Using radiation and chemotherapy (cisplatin plus etoposide), the patients either were treated sequentially (n = 12) or concurrently (n = 18). The relation between therapeutic response and retention of each tracer was analyzed. The detectability of radioresistance was examined. RESULTS: In patients treated with sequential therapy, the response to radiation was predicted by (99m)Tc-TF retention, whereas (201)Tl retention was found not to be predictive. Regardless of whether the sequential or concurrent protocol was applied, 14 of 18 tumors with high (99m)Tc-TF retention (>/= 15%) exhibited a favorable response to chemoradiotherapy whereas all 12 tumors with low (99m)Tc-TF retention (

Extraosseous metastases of hepatocellular carcinoma detection and therapeutic assessment with Tc-99m PMT SPECT.

Owing to recent advances in imaging technology and radiologic intervention, survival rates in patients with hepatocellular carcinoma have improved markedly. However, such prolonged survival has resulted in an increase in extrahepatic metastases. Tc-99m (Sn)-N-pyridoxyl-5-methyltryptophan (Tc-99m PMT), developed for hepatobiliary scintigraphy, has been used to visualize extrahepatic metastases, with most related reports limited to osseous metastases. The authors report two cases of hepatocellular cancer presenting as a hypopharyngeal metastasis and intraperitoneal dissemination along the tract of a fine-needle biopsy. Lesions undetectable on planar imaging could be visualized by Tc-99m PMT SPECT.

Diagnosis of lung cancer using two-phase Tl-201 SPECT and modified retention image to view tumor in the collapsed lung: comparison with bolus CT.

In this report the usefulness of Tl-201 SPECT and modified retention images in the differentiation of lung cancer and postobstructive collapse was studied. Two-phase Tl-201 SPECT was performed in 20 lung cancer lesions in which postobstructive collapse was suspected on CT. Retention imaging was done afterward. Three types of Tl-201 images were compared with the bolus CT images. Bolus CT differentiated lung cancer from postobstructive collapse in 7 of the 20 lesions (35%). Tl-201 SPECT differentiated the two conditions in 9 of 20 lesions (45%) on early Tl-201 SPECT and in 13 of 20 lesions (65%) on delayed imaging. With modified retention images, differentiation was possible in 13 of 20 lesions (65%). By combining delayed Tl-201 SPECT and modified retention images, lung cancer alone could be demonstrated in 18 of 20 lesions (90%). Combined delayed Tl-201 SPECT and modified retention images were more effective than bolus CT in delineating the extent of lung cancer in the presence of postobstructive collapse.

Dual-isotope SPECT diagnosis of a skull-base metastasis causing isolated unilateral hypoglossal nerve palsy.

We describe a 48-year-old female with an isolated unilateral hypoglossal nerve palsy caused by a skull base metastasis from breast cancer. The patient had a medical history of conservative breast therapy for breast cancer. Although the cause of such a neurological deficit includes various pathologies, the reports focusing on metastatic tumor have been limited in number. Radiologic investigation showed a mass involving both the right hypoglossal canal and the clival edge. Swelling of the hypoglossal nerve was observed in views including its canal. Three-dimensional CT images demonstrated the tumor protruding from the enlarged external orifice of the hypoglossal canal. In the present report we mentioned a nuclear medicine procedure to visualize and characterize the small, abnormal tissue in the skull base. Dual-isotope SPECT confirmed an abnormal uptake of 99mTc-HMDP around the hypoglossal canal and a 201Tl-positive elongated lesion running along the hypoglossal nerve.

Dual isotope SPECT in malignant Jacod's syndrome.

A case is presented of metastatic tumor causing Jacod's syndrome: total ophthalmoplegia, blindness, and trigeminal neuralgia. Abnormal soft tissue invading the orbital apex, anterior clinoid process, and cavernous sinus was difficult to assess by CT and MRI, but dual-isotope SPECT including Tc-99m HMDP bone imaging and Tl-201 tumor imaging strongly suggested that the cause of this rare syndrome was a small metastatic tumor. Although the therapeutic effect was also difficult to assess by anatomic imaging alone, dual-isotope SPECT after radiation therapy showed a decline of tumor viability.

Relationship between ATP synthesis and 201Tl uptake in transformed and non-transformed cell lines.

201Tl tumour imaging is an established procedure, but little is known about its biological significance in transformed and non-transformed cells. In investigating the relationship between 201Tl uptake and intracellular ATP, we wished to determine whether the observed difference in delayed uptake is attributable to re-uptake via Na-K ATPase by using transformed (HeLa) and non-transformed (human fibroblast: hFB) cell lines. In each cell line, ATP was measured using the Luciferin-Luciferase method (LLM). The change in 201Tl uptake was assessed under conditions of mitochondrial suppression. Additionally, we assessed whether glycolysis is involved in 201Tl uptake under conditions of mitochondrial suppression and anaerobic incubation. Re-uptake via Na-K ATPase (HeLa vs hFB: 37.3 vs 24.2%) showed a clear difference in delayed uptake between HeLa and hFB. With HeLa, 201Tl uptake decreased biphasically with a reduction in ATP levels, whereas with hFB a linear correlation was evident. Despite the suppression of mitochondrial potential, a 5% glucose loading accelerated glycolysis with HeLa, and increased ATP (10.0 +/- 4.0%) and 201Tl uptake (16.2 +/- 3.0%). Conversely, neither ATP nor 201Tl uptake increased with hFB. Our results provide evidence that 201Tl uptake in transformed cells is related to enhanced glycolysis as well as mitochondrial ATP synthesis.

Cholecystoparesis with diabetic autonomic neuropathy.

A 69-year-old male diabetic patient was hospitalized with pneumonia in February 1996. Abdominal ultrasonography performed as a routine examination on admission revealed marked dilatation of gallbladder with a fasting maximal size of 25.7 cm2 compared with 8.8 +/- 2.9 cm2 evaluated in 30 male healthy controls aged 67 +/- 8 years old. Four months after recovery from pneumonia, abnormal gallbladder dilatation remained unchanged (25.0 cm2), while dilatation had not been observed on an examination performed 6 years earlier (9.8 cm2). Because of accompanying neurological defects, we suppose that cholecystoparesis may be caused by progression of autonomic neuropathy in this patient with diabetes mellitus.