Lung amyloid nodule detected by 99mTc-aprotinin scintigraphy

We present a case in which an amyloid lung nodule was diagnosed preoperatively by amyloid scintigraphy (99m)Tc-aprotinin. A 65-year-old man complained of marked weight loss (9 kg) over a period of 6 months. An abnormal shadow in the middle field of the right lung was detected on chest X-ray, corresponding to a 16-mm nodule in the right middle lobe on thoracic computed tomography (CT). Total protein and immunoglobulin G levels were elevated to 8.3 and 2245 mg/dl, respectively, but other blood tests including several tumor marker levels and Cryptococcus antibodies were all within normal range. Fluorodeoxyglucose positron emission tomography showed no uptake by the lung nodule, so lung amyloidosis was considered as differential diagnosis. To avoid risk of bleeding on bronchoscopy, noninvasive amyloid scintigraphy using (99m)Tc-aprotinin was first performed. A nodular, abnormal accumulation was observed in the right middle lung lobe. Diagnostic imaging strongly suggested amyloidosis, so video-assisted thoracic surgery was performed rather than bronchoscopy. Pathological samples showed positive staining with Congo red, and A-λ amyloidosis was diagnosed on the basis of immunostaining. Scintigraphy using (99m)Tc-aprotinin offers a useful, noninvasive method for assessing lung amyloidosis.     

Technetium-99m (V) DMSA uptake in amyloidosis

Technetium-99m(V) DMSA scintigraphy was performed in two patients with pathologically confirmed amyloidosis associated with plasmacytoma. Significant uptake of the tracer was found in the deposition of amyloid. Technetium-99m(V) DMSA scintigraphy could be useful in determining the appropriate region of biopsy and in forecasting the prognosis of patient with plasmacytoma.     

Soft-tissue uptake of 99mTc-diphosphonate and 99mTc-pyrophosphate in amyloidosis

This study describes the results of scintigraphy with 99mTc-labeled methylene-diphosphonate (99mTc-MDP) and pyrophosphate (99mTc-PYP) as a noninvasive test for the distribution of organ involvement in five different types of amyloidosis. Scintigraphy with 99mTc-labeled phosphates appeared to be a sensitive noninvasive screening test for the extent and the distribution of organ involvement in systemic AA and systemic AL amyloidosis as well as in local bronchial amyloid, local dermal amyloid, and familial amyloidotic polyneuropathy. Echocardiography, however, was more sensitive for demonstrating cardiac involvement in systemic amyloidosis than 99mTc-MDP or 99mTc-PYP scintigraphy. 99mTc-MDP images showed a better contrast than 99mTc-PYP images, although there was no difference in the extent or the intensity of soft-tissue uptake.     

Noninvasive diagnosis of cardiac involvement by technetium-99m-pyrophosphate (Tc-99m PYP) myocardial scintigraphy in 2 cases of familial amyloid polyneuropathy and 1 case of secondary amyloidosis

To validate the significance of technetium-99m-pyrophosphate (Tc-99m PYP) myocardial scintigraphy in diagnosing cardiac amyloidosis, 2 patients with familial amyloid polyneuropathy (FAP) and 1 patient with amyloidosis secondary to chronic rheumatic arthritis were studied. All three patients had echocardiographic abnormalities, which were increased wall thickness of the interventricular septum and the left ventricular posterior wall, and granular sparkling appearance in the septum. In 2 patients with FAP, abnormal myocardial uptake of Tc-99m PYP was diffusely detected in Tc-99m PYP SPECT. In the remaining 1 patient with secondary amyloidosis, however, Tc-99m PYP SPECT showed no abnormality, although we had confirmed the presence of myocardial amyloid deposits (type AA amyloid protein) with high amount in the histological examination. Thus, these results indicate that Tc-99m PYP scintigraphy may have a limitation in detecting cardiac involvement in secondary amyloidosis although it is useful in FAP.     

Features of hepatic cavernous hemangioma on planar and SPECT Tc-99m-labeled red blood cell scintigraphy.

PURPOSE: To determine the value and diagnostic accuracy of planar and SPECT Tc-99m-labeled red blood cell (Tc-99m RBC) scintigraphy in the investigation of suspected hepatic cavernous hemangioma as found on ultrasound. PATIENTS AND METHODS: One hundred patients, 89 women (89%) and 11 men (11%), between 22 and 67 years old (mean age, 38 years) were evaluated for liver masses found on abdominal ultrasound. All the patients had previous Tc-99m RBC scintigraphy. The size of the lesions ranged from 1 to 9 cm. The final diagnosis was reached through cytologic biopsy, or histopathologic tests (or all of these). RESULTS: One hundred thirty lesions were found. With regard to the distribution of the lesions, 116 (89%) were single; 14 (3%) were multiple, with 118 (91%) in the right lobe and 12 (9%) in the left lobe; 83 (64%) were posterior; and 47 (36%) were anterior. With respect to the pattern of radioactivity fill-in, 86 (66%) lesions were typical and 44 (34%) were atypical. The results of Tc-99m RBC scintigraphy showed sensitivity, specificity, and positive and negative predictive and accuracy values of 97%, 83%, 98%, 77%, and 96% respectively. The use of SPECT improved the sensitivity value by 11% for lesions of 1 to 2 cm. CONCLUSIONS: Tc-99m RBC scintigraphy is the noninvasive technique most helpful in the diagnosis of hepatic hemangioma, especially in those at risk for lesion rupture or bleeding. SPECT should be performed whenever planar imaging fails to show the lesion by 2 hours. The use of ultrasound should precede scintigraphy for two important reasons: the size and the location of the lesion. Location of the lesion (anterior or posterior) is important for optimal gamma camera acquisition parameters. Lesions less than 1 cm are cannot be detected because they are beyond the limit of spatial resolution of the gamma camera we used.     

CT and 99mTc-DMSA scintigraphy in adult acute pyelonephritis: a comparative study

PURPOSE: The aim of this prospective study was to evaluate the relative value of CT and (99m)Tc-DMSA scintigraphy in the diagnosis of acute pyelonephritis (APN) in adult patients suspected of having urinary tract infection. METHOD: The study was conducted in 36 patients presenting with symptoms suggestive of urinary tract infection. Plain B-mode sonography, CT with contrast medium, and (99m)Tc-DMSA scintigraphy of the kidneys were performed in all patients. Both CT and (99m)Tc-DMSA scintigraphy were performed within 72 h after admission. RESULTS: Twelve patients with clinical and biological signs of urinary tract infection had no CT or (99m)Tc-DMSA scintigraphy abnormalities. Among these patients, lower urinary tract infection was found in 10 patients and 2 patients had ureteral obstruction. In the 24 remaining patients, the diagnosis of APN was made. Among these patients, a correlation was found between CT and (99m)Tc-DMSA scintigraphy in 11 cases. In two cases, both examinations were normal, and in nine cases, both were abnormal. In 11 cases of the 13 remaining patients, abnormal CT was found with normal (99m)Tc-DMSA scintigraphy, whereas the 2 last cases had normal CT and abnormal (99m)Tc-DMSA scintigraphy results. In two cases, bilateral lesions found on CT manifested as unilateral abnormalities on (99m)Tc-DMSA scintigraphy images. CONCLUSION: The diagnosis of APN in adult patients is based on clinical presentation and biological findings. Few studies have compared (99m)Tc-DMSA scintigraphy with CT in the detection of parenchymal involvement in APN. We conclude that CT is more accurate than (99m)Tc-DMSA scintigraphy in the detection of APN lesions in adult patients.     

Use of 99mTc (V) DMSA scintigraphy in the detection and localization of intestinal inflammation: comparison of findings and colonoscopy and biopsy

PURPOSE: To evaluate the potential use of technetium 99m (99mTc) (V) dimercaptosuccinic acid (DMSA) scintigraphy in the detection and localization of intestinal inflammation. MATERIALS AND METHODS: In a prospective study, 62 patients who were suspected of having intestinal inflammation and 30 control subjects were enrolled. All patients underwent 99mTc (V) DMSA scintigraphy and colonoscopy with biopsy within 1 week. 99mTc (V) DMSA scintigrams were interpreted blindly with respect to clinical information, and radiotracer uptake in the bowel segments was graded. The findings were then compared with the results of the colonoscopy and colonoscopic biopsy. RESULTS: In the detection of intestinal inflammation, findings at 99mTc (V) DMSA scintigraphy were as follows: true-positive in 55, false-positive in two, true-negative in 32, and false-negative in three. Overall sensitivity was 95%; overall specificity, 94%; and overall accuracy, 95%. CONCLUSION: Our results show that 99mTc (V) DMSA scintigraphy is a useful noninvasive diagnostic test for the detection and localization of intestinal inflammation.     

Soft-tissue uptake of99m-Tc-diphosphonate and99mTc-pyrophosphate in amyloidosis

This study describes the results of scintigraphy with^99mTc-labeled methylene-diphosphonate (^99mTc-MDP) and pyrophosphate (^99mTc-PYP) as a noninvasive test for the distribution of organ involvement in five different types of amyloidosis. Scintigraphy with^99mTc-labeled phosphates appeared to be a sensitive noninvasive screening test for the extent and the distribution of organ involvement in systemic AA and systemic AL amyloidosis as well as in local bronchial amyloid, local dermal amyloid, and familial amyloidotic polyneuropathy. Echocardiography, however, was more sensitive for demonstrating cardiac involvement in systemic amyloidosis than^99mTc-MDP or^99mTc-PYP scintigraphy.^99mTc-MDP images showed a better contrast than^99mTc-PYP images, although there was no difference in. the extent or the intensity of soft-tissue uptake.     

Cardiac and pleuropulmonary AL amyloid imaging with technetium-99m labelled aprotinin

Antiproteases are known to be present in amyloid deposits. We evaluated the possibility of using an anti-serine protease (aprotinin) labelled with technetium-99m (TcA), usually employed as a cortical renal tracer, for the imaging of amyloid deposits. Because of the known high uptake of TcA by the kidneys, we limited our analysis to extra-abdominal amyloid localizations. We report the scintigraphic findings observed in 24 patients with light chain amyloidosis (AL) and one with a hereditary form who were known or suspected to have extra-abdominal involvement. Planar scans obtained 100 min after i.v. TcA administration showed myocardial accumulation in 11 patients, pleuropulmonary accumulation in nine, pericardial accumulation in two and localization in the neck region (thyroid, salivary glands and tongue) in eight. TcA scintigraphy was negative in five patients without clinical or laboratory evidence of extraabdominal involvement, as well as in 12 control group patients with cardiac and renal diseases. These preliminary results indicate TcA to be a low-cost, readily available radiopharmaceutical for imaging of extra-abdominal involvement in AL type amyloidosis.     

99mTc DPD is the preferential bone tracer for diagnosis of cardiac transthyretin amyloidosis

We emphasize the role of Tc-99m-3,3-diphosphono-1,2-propanodicarboxylicacid (DPD) scintigraphy as a noninvasive tool to distinguish transthyretin (TTR)-related cardiac amyloidosis from other forms of cardiac amyloidosis. We report the case of a 76-year-old male patient suffering from congestive heart failure in whom imaging investigation by DPD scintigraphy showed a strong cardiac uptake highly suggestive of TTR amyloidosis variant. TTR-related cardiac amyloidosis was confirmed on myocardial biopsies by immunohistochemistry analysis. This case supports the growing interest in DPD scintigraphy for typing cardiac amyloidosis and for its contribution in the place of invasive myocardial biopsy.     

In vitro affinity of 99Tcm-labelled N2S2 conjugates of chrysamine G for amyloid deposits of systemic amyloidosis

To date, systemic amyloidosis is diagnosed histologically in vitro using Congo red staining or in vivo using iodine-123 serum amyloid P component (123I-SAP) scintigraphy. 99Tcm-labelled derivatives of chrysamine G (CG), a lipophilic analogue of Congo red, were synthesized as potential tracer agents for direct and quantitative scintigraphic evaluation of amyloid deposits. To determine the affinity of 99Tcm-MAMA-CG, 99Tcm-Me4MAMA-CG and 99Tcm-MAMA-CG diethyl ester for amyloid, in vitro autoradiography was performed on sections of human kidney biopsy cylinders from kidneys with amyloid deposits (types AA, Alambda and Akappa) or control kidney tissue after incubation with the respective tracer agents. The binding of 99Tcm-MAMA-CG and its tetramethyl derivative was higher to kidney biopsy material with amyloid deposits of the AA, Alambda or Akappa type compared with control kidney tissue. This higher binding was prevented by the presence of 10 microM Congo red in the incubation medium. The diethyl ester of 9Tcm-MAMA-CG did not demonstrate increased binding to Congo red-positive kidney tissue. In conclusion, 99Tcm-MAMA-CG and 99Tcm-Me4MAMA-CG localize specifically to amyloid deposits in human kidney tissue, suggesting that these tracer agents may be applicable as specific targeting agents for diagnostic purposes in clinical amyloidosis.     

Nuclear imaging in cardiac amyloidosis

Amyloidosis is a disease characterized by depositions of amyloid in organs and tissues. It can be localized (in just one organ) or systemic. Cardiac amyloidosis is a debilitating disease and can lead to arrhythmias, deterioration of heart function and even sudden death. We reviewed PubMed/Medline, without time constraints, on the different nuclear imaging modalities that are used to visualize myocardial amyloid involvement. Several SPECT tracers have been used for this purpose. The results with these tracers in the evaluation of myocardial amyloidosis and their mechanisms of action are described. Most clinical evidence was found for the use of ¹²³I-MIBG. Myocardial defects in MIBG activity seem to correlate well with impaired cardiac sympathetic nerve endings due to amyloid deposits. ¹²³I-MIBG is an attractive option for objective evaluation of cardiac sympathetic level and may play an important role in the indirect measurement of the effect of amyloid myocardial infiltration. Other, less sensitive, options are ^99mTc-aprotinin for imaging amyloid deposits and perhaps ^99mTc-labelled phosphate derivatives, especially in the differential diagnosis of the aetiology of cardiac amyloidosis. PET tracers, despite the advantage of absolute quantification and higher resolution, are not yet well evaluated for the study of cardiac amyloidosis. Because of these advantages, there is still the need for further research in this field.     

Iodine-123-labelled serum amyloid P component scintigraphy in amyloidosis

This study describes the results of scintigraphy with iodine-123-labelled serum amyloid P component (SAP) as a means of establishing the distribution of organ involvement in amyloidosis. The significance of ¹²³I-SAP scans obtained in 15 patients with biopsy-proven AA or AL amyloidosis is discussed. Biopsy-proven amyloidosis was typically confirmed by scintigraphy, though such confirmation was not obtained in the kidneys in six patients with histological proof of extensive renal amyloid deposition. This lack of uptake may have been due to the accumulation of a major part of the ¹²³I-SAP in the spleen and/or liver. Twenty-four hour whole-body retention of ¹²³I-SAP was higher in patients with amyloidosis than in controls. Twenty-four hour tracer accumulation of the radioactivity in the extravascular compartment was notably greater in patients than in controls and appeared to be a good diagnostic criterion. We conclude that ¹²³I-SAP scintigraphy may be helpful for the evaluation of organ involvement not only in patients with biopsy-proven amyloidosis but also when a biopsy cannot be performed or when a strong suspicion of amyloidosis exists in spite of repeated negative biopsises. Correspondence to: X. Marchandise     

Amyloid imaging mismatch

An 82-year-old man with suspected systemic amyloidosis and complete atrioventricular block underwent vascular biopsy during his pacemaker implantation with pathology showing amyloid deposits. 99mTc-aprotinin SPECT revealed increased radiotracer uptake along the left ventricular wall, consistent with cardiac amyloidosis. 11C-PiB PET/CT performed for the evaluation of amyloid deposits in the brain showed findings suggestive of Alzheimer disease without abnormal radiotracer concentration in the myocardium to match the 99mTc-aprotinin SPECT findings. Dynamic PET images showed increased 11C-PiB concentration in the left ventricular myocardium at 2 minutes after injection, with subsequent tracer clearance by approximately 5 minutes, consistent with normal 11C-PiB biodistribution.     

Absent skeletal uptake of <Superscript>99m</Superscript>Tc-hydroxymethylene diphosphonate in the presence of AL-type amyloidosis associated with multiple myeloma

A 66-year-old woman with congestive heart failure suspected to have multiple myeloma underwent bone scintigraphy. The bone scintigraphy using technetium-99m hydroxymethylene-diphosphonate showed the following interesting findings: absent skeletal uptake; increased gastrointestinal, myocardial, and soft tissue uptake; migration of radionuclide to bilateral pleural effusions. Histopathological examination revealed that the patient suffered from AL-type amyloidosis associated with multiple myeloma. Extraosseous uptake is often observed on bone scintigraphy in amyloidosis patients, but in many cases skeletal uptake is preserved. The simultaneous presentation of these findings is rare.     

^99mTc（V）—DMSA骨显像诊断骨转移瘤的临床价值

目的：评价99mTc（V）－DMSA显像在骨转移瘤诊断中的意义。材料和方法：对91例疑骨转移瘤患者行99mTc（V）DMSA全身显像，并与99mTc-MDP全身骨显像及其它检查对比。结果：74例证实存在骨转移瘤者，99mTc．MDP骨显像均显示异常放射性浓聚，99mTc（V）-DMSA显像72例显示了与99mTc-MDP显像某些相同部位的放射性浓聚，2例99mTc（V）DMSA显像阴性。17例骨良性病变，99mTc－MDP骨显像显示轻度异常放射性浓聚，而99mTc（V）-DMSA显像却未见异常的放射性浓聚。结论：99mTc（V）－DMSA诊断骨转移瘤的特异性比99mTc-MDP骨显像高，在骨良恶性肿瘤鉴别诊断中具有重要的临床价值。     

Integrin receptor imaging of breast cancer: a proof-of-concept study to evaluate 99mTc-NC100692.

The present study was a proof-of-concept study to provide an initial indication of the efficacy and safety of imaging malignant breast tumors using (99m)Tc-NC100692. The agent is a small peptide with high affinity for integrin receptors that are upregulated and expressed preferentially on proliferating endothelial cells. METHODS: Sixteen patients with suggestive mammographic findings and 4 patients with benign lesions were included. The "standard of truth" was based on the histopathologic diagnosis of the recruited patients. All subjects received up to 75 microg of (99m)Tc-NC100692 with an average (99m)Tc activity of 694 MBq (range, 561-747 MBq). Safety endpoints were treatment-emergent adverse events (AEs) and changes in a limited physical examination, electrocardiogram (ECG) recordings, blood biochemistry, hematology, coagulation, vital signs, and urine analysis after administration of (99m)Tc-NC100692 and throughout the 24-h follow-up. Static images and SPECT were acquired between 40 min and 2.5 h after injection of the agent. Two experienced nuclear medicine physicians read the images in a nonblinded fashion. RESULTS: Nineteen of 22 malignant lesions were detected using (99m)Tc-NC100692 scintigraphy. Twenty lesions confirmed as malignant by histopathology were seen on mammography or ultrasound. Two additional lesions were identified from histopathology alone. Safety parameters evaluated through the follow-up period of 2.5 h included clinical laboratory tests, vital signs, and ECG. Five of 20 subjects experienced nonserious AEs, and all AEs were classified as mild. One subject experienced an AE (dysgeusia) possibly related to administration of (99m)Tc-NC100692. This AE was mild and lasted only for a few minutes. No deaths, serious AEs, or withdrawals due to AEs occurred during the study. CONCLUSION: Nineteen of 22 malignant lesions (86%) were clearly detected via scintigraphic imaging after administration of (99m)Tc-NC100692. Overall, the efficacy data in subjects with suspected breast lesions suggest that (99m)Tc-NC100692 scintigraphy may be effective in detecting malignant lesions. The use of (99m)Tc-NC100692 in subjects with breast cancer is safe and well tolerated. Further studies are warranted to assess the clinical potential of (99m)Tc-NC100692.     

Clinical validation of the avidin/indium-111 biotin approach for imaging infection/inflammation in orthopaedic patients.

We report here the results of a validation study of the avidin/indium-111 biotin approach in patients with skeletal lesions. This study involved 54 patients with orthopaedic conditions: 20 patients with intermediate suspected osteomyelitis of the trunk, 19 patients with infection/inflammation of prosthetic joint replacements, and 15 patients with suspected osteomyelitis of appendicular bones. Avidin (3 mg) was injected as an i.v. bolus, followed 4 h later by 111In-biotin; imaging was acquired 30 min and 16-18 h after administration of 111In-biotin. Technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO)-labelled leucocyte scintigraphy was performed in 39/54 patients. The overall sensitivity of the avidin/111In-biotin scan was 97.7% (versus 88.9% for 99mTc-HMPAO leucocyte scintigraphy). While the diagnostic performance of avidin/111In-biotin scintigraphy was similar to that of 99mTc-HMPAO leucocyte scintigraphy in patients with prosthetic joint replacements or osteomyelitis of appendicular bones, the avidin/111In-biotin approach clearly performed better than 99mTc-HMPAO leucocyte scintigraphy in patients with suspected osteomyelitis of the trunk (100% sensitivity, specificity and accuracy versus 50% sensitivity, 100% specificity and 66.7% accuracy for 99mTc-HMPAO-leucocyte scintigraphy). These results demonstrate the feasibility of the avidin/111In-biotin approach for imaging sites of infection/inflammation in the clinical setting. Although no systematic advantages of avidin/111In-biotin scintigraphy were found versus 99mTc-HMPAO leucocyte scintigraphy, the newer scintigraphic method is more practicable and involves lower biological risk for the operators.     

A comparative study between MR sialography and salivary gland scintigraphy in the diagnosis of Sjögren syndrome

PURPOSE: The purpose of this work was to compare the diagnostic accuracy of MR sialography with that of salivary gland scintigraphy in Sj?gren syndrome. METHOD: One hundred thirty patients clinically suspected of having Sj?gren syndrome were examined by MR sialography and salivary gland scintigraphy. A labial gland biopsy was performed in all patients. Imaging findings of MR sialography and salivary gland scintigraphy were compared with the results of labial gland biopsy. RESULTS: From the results of labial gland biopsy, the diagnosis of Sj?gren syndrome was established in 80 patients. Abnormally high T2 signal intensity areas on MR sialography and decreased uptake and delayed excretion of [(99m)Tc]pertechnetate on salivary gland scintigraphy were well seen in patients with Sj?gren syndrome. For the diagnosis of Sj?gren syndrome, salivary gland scintigraphy showed higher sensitivity than MR sialography. On the other hand, MR sialography showed higher specificity and positive predictive value (PPV) than salivary gland scintigraphy. Overall diagnostic accuracy was 83% for MR sialography and 72% for salivary gland scintigraphy. CONCLUSION: The high PPV of MR sialography suggests that MR sialography is the preferred imaging modality in patients suspected of having Sj?gren syndrome.     

Usefulness of 18F-FDG PET-directed skeletal biopsy for metastatic neoplasm

RATIONALE AND OBJECTIVES: Technium-99m methylene diphosphonate (99mTc-MDP) bone scintigraphy and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) are useful imaging modalities to detect skeletal metastases. Several other conditions such as infection, fractures, and arthritis can cause false-positive results with either modality. However, PET is felt to be more specific than bone scintigraphy for malignancy. Our objective was to investigate the value of PET scan compared with bone scintigraphy for directing biopsies in patients with suspected metastatic bone lesions. MATERIALS AND METHODS: Retrospective case series of subjects with undergoing skeletal biopsy of suspected metastases detected by 99mTc-MDP scintigraphy or 18F-FDG PET scan. Reference standards were pathologic reports and follow-up for 6 months. The diagnostic test performance measures of true positive (TP), false positive (FP), and positive predictive value (PPV) were calculated for each group. The PPV with 95% confidence intervals (CI) was compared using the Fisher exact test. RESULTS: There were a total of 68 subjects. PET-directed skeletal biopsies (n = 39) showed 35 TP, 4 FP, and an 89.7% PPV (95% CI: 75.7-97.1%). Bone scintigraphy directed biopsies (n = 29) had 21 TP, 8 FP, and 72.4 % PPV (95% CI: 52.7-82.7%). The PPV was not significantly different between the groups (P = .10). CONCLUSION: This study supports that PET can be used to effectively direct bone biopsies to confirm metastatic neoplasm and suggests that PET may provide incremental improvement to diagnostic yield over bone scintigraphy. The role of PET compared with bone scintigraphy for directing skeletal biopsies warrants further verification.