Tc-99m depreotide SPECT demonstrates photon-deficiency in the thoracic vertebrae after adjunct radiation therapy of lung cancer: Correlation with MRI and bone scintigraphy

Fifteen months after right lobe lobectomy with adjunctive radiation therapy for squamous cell carcinoma, a patient 53-yr-old man underwent Tc-99m depreotide chest single photon emission tomography (SPECT). In addition to two focal areas of abnormally increased uptake in the right lung, the Tc-99m depreotide SPECT showed cold areas in the middle thoracic vertebrae. Photopenic areas in the 6th and 7th thoracic vertebrae were shown on a bone scintigraphy. T1 weighted magnetic resonance imaging (MRI) of the spine showed fatty replacement of the marrow and Schmorl's nodes involving the 5th to 11th thoracic vertebrae. The vertebrae are normally visualized in Tc-99m depreotide SPECT imaging study, and lung tumor is usually somatostatin receptor positive with demonstrable activity in the lung. Absent uptake in the vertebrae in the fatty replacement of the marrow and multiple and giant vertebral Schmorl's nodes in the correspondent vertebrae in MRI may reflect visualization of vertebrae due to Tc-99m depreotide localizing in the bone marrow. Of the three imaging modalities, MRI showed the widest areas of thoracic vertebral involvement. One should be aware that a cold lesion in the vertebrae on Tc-99m depreotide imaging study may result from irradiation and may indicate the presence of a benign lesion in the bone marrow.     

Unusual extracardiac findings detected on myocardial perfusion single photon emission computed tomography studies with Tc-99m sestamibi

The authors describe the incidence and various uptake patterns of Tc-99m sestamibi (MIBI) in the extracardiac area due to unusual causes on myocardial perfusion single photon emission computed tomography (SPECT) studies. Seven patients are presented in whom incidental extracardiac findings were observed during the interpretation of the raw data besides the routine evaluation of myocardial reconstructed SPECT slices. These 7 patients were detected out of 582 consecutive patients (1.2%) who had myocardial perfusion SPECT with Tc-99m MIBI. The findings on the raw data led to additional reconstruction of thoracic SPECT images and eventually detailed examination of the extracardiac area. Two of the patients underwent surgery because of incidental extracardiac findings (thymoma and multinodular goiter) on cardiac scintigraphy. Other causes of increased extracardiac activity were the intestine protruded through the left hemithorax, uptake in the pulmonary arterial wall, and pulmonary interstitial fibrosis due to sarcoidosis. The reasons for decreased Tc-99m MIBI accumulation in the extracardiac area in the 2 other patients were significantly dilated pulmonary arteries and hydatic cyst, which were not defined before to our knowledge. Familiarity with the normal biodistribution and variable uptake patterns in the raw images becomes necessary during the interpretation of myocardial SPECT in order not to miss very unusual incidental extracardiac uptake or information that could lead to alteration in patient management. Potential underlying mechanisms of extracardiac Tc-99m MIBI accumulation are discussed, and the literature about noncardiac Tc-99m MIBI findings detected on myocardial perfusion SPECT studies was reviewed.     

The role of Tc-99m (V) DMSA scintigraphy in the diagnosis and follow-up of lung cancer lesions

Objective To define the role of Tc-99m (V) dimercaptosuccinic acid (DMSA) scanning in the detection of lung cancer (LC) and its metastases, and monitoring the response of LC lesions (LCL) to chemo/radiotherapy (TH). Methods Tc-99m (V) DMSA whole-body scans, planar thorax views, and thorax Single-photon emission computed tomography (SPECT) images were obtained both 30 min (early) and 5 h (late) after Tc-99m (V) DMSA administration in 12 small/nonsmall cell LC patients (11 men, 1 woman; mean age 59 years). Five patients also had bone scans. The same scintigraphic protocol was performed in 7 of 12 patients, 3 weeks after first-line TH. TH response was evaluated visually in all LCL and semiquantitatively in primary tumors (PT) of six patients, by comparing the tumor uptake ratios (TUR) of pre-TH and post-TH Tc-99m (V) DMSA SPECT [TUR = mean counts of region of interests (ROI) in PT/mean counts in contralateral ROI]. In seven patients, a 6-month survival was determined. Results Tc-99m (V) DMSA accumulated in 34 LCL (11 PT, 19 bone metastases, 1 suprarenal mass, 1 axillary node, 2 supraclavicular nodes). A total of 11 patients displayed Tc-99m (V) DMSA uptake in LCL and one patient did not show uptake. In six patients, SPECT imaging showed deeply located PT in the lung parenchyma better than planar views. In five patients, both planar and SPECT views revealed peripherally located PT in the lungs. Early scans showed 18 LCL and late scans displayed all the LCL. Nine bone metastases on pre-TH Tc-99m (V) DMSA scans revealed matched areas of increased Tc-99m methylene diphosphonate (MDP) uptake on bone scans; six bone metastases were additionally detected on Tc-99m (V) DMSA scans when compared with bone scans, and four bone metastases on Tc-99m (V) DMSA scans could not be compared with bone scans because bone scan was not performed. In one patient, Tc-99m (V) DMSA scans became positive for bone metastases on post-TH later than the bone scans for some of the bone metastases. Neither planar nor SPECT imaging showed mediastinal lesions defined on thorax CT in nine patients. On TH monitoring, 17 LCL showed diminished Tc-99m (V) DMSA uptake, one disappeared, four were unchanged, three displayed increased uptake, and five new lesions were established. Of the six patients, TUR in PT increased in two (one survived), decreased in one (exitus), was unchanged in two (two exitus) on post-TH scans, and PT totally disappeared in one (survived) patient. Conclusions Tc-99m (V) DMSA scans are useful in detecting LCL, except for those around the blood pool regions, making it a promising modality to monitor TH response. Obtaining a single fifth hour late Tc-99m (V) DMSA scan is appropriate. SPECT should be applied to all patients for the detection of deeply located lesions.     

Somatostatin receptor scintigraphy with 99mTc-Depreotide (NeoSpect) in discriminating between malignant and benign lesions in the diagnosis of lung cancer: a pilot study

Purpose: To evaluate the diagnostic value of a new somatostatin analog, ^99mTc-Depreotide, in differentiating benign from malignant lesions in patients with pulmonary nodules or masses. Material and Methods: A pilot study was performed on 28 patients referred to our Lung Department on suspicion of lung cancer. A chest X-ray, computed tomography (CT) of the thorax and upper abdomen, and scintigraphy were done - scintigraphy following the administration of 740 MBq ^99mTc-Depreotide. Planar and tomographical imaging of the thorax and whole-body scanning with a gamma camera were done, and diagnostic outcome of the scintigrams was compared to CT, pathology, and clinical outcome. Results: Of 21 patients who had a focal high uptake of Depreotide, 17 were malignancies. One patient had two lesions with high Depreotide uptake, lung cancer, and pneumonia in the contralateral lung. Two patients with sarcoidosis and one with bilateral round atelectasis also had high Depreotide uptake bilaterally. Seven of the 8 patients with no uptake were true negative: 5 hamartomas and 2 round atelectases. One small lung cancer in the pleura sinus did not have Depreotide uptake. Conclusion: The somastotatin analog Depreotide is promising for discriminating between malignant and benign lung lesions.     

Illustrations of abdominal abnormalities on 99mTc tetrofosmin gated cardiac SPECT

BACKGROUND: 99mTc tetrofosmin is predominantly cleared by the hepatobiliary system and its scan is analogous to a cholescintigraphy. The radiopharmaceutical may be localized in the bone marrow. During cardiac acquisition, when the area being viewed includes the lower thorax and abdomen, abnormalities of the liver, gallbladder and kidneys, and the radioactivity in the oesophagus, stomach and bowel, as well as bone marrow uptake, can be depicted by routine raw data cine images. Excluding the intrathoracic abnormalities, these abdominal abnormalities are illustrated in this paper. METHODS AND MATERIALS: Retrospectively, we reviewed the raw data cine images from 566 patients. These images were 180 degrees or 360 degrees rotation and showed the abdominal organs and thoracic cage, including the ribs, sternum and spine. We found 234 abnormalities, which were correlated with radiography, laboratory and clinical findings. RESULTS: Intra-abdominal abnormalities included bone marrow visualization, 93 occurrences (39.7%); duodeno-gastric (DG) and entero-gastric (EG) reflux, 47 (20.1%); non-visualization of the gallbladder, including possible causes of cholelithiasis, acute cholecystitis, or cholecystectomy, 31 (13.2%); elevation of the right diaphragm and depression of diaphragm, 30 (12.8%); renal abnormalities, including absent kidney, renal atrophy and cyst, 12 (5.1%); splenomegaly, 10 (4.3%); liver, including hepatomegaly and cirrhosis of the liver, eight (3.4%); and breast attenuation resulting in photopenia in the liver, three (1.2%). CONCLUSIONS: (1) The bone marrow uptake of the vertebrae accounts for almost 40% of the abdominal abnormalities, and is usually concordant with anaemia; (2) DG and EG refluxes represent 20% of abdominal abnormalities; they may have a clinical impact and may or may not interfere with SPECT processes and result in artifacts of the inferior wall of the left ventricle; (3) non-visualization of the gallbladder should prompt a search for cholelithiasis; and (4) benign renal cyst or cirrhosis of the liver could also be demonstrated. These coincidental findings may be included in routine cardiac SPECT reports that may have clinical impact because they give the referring physician the chance to pursue further clinical investigation.     

Bone imaging of sternocostoclavicular hyperostosis in palmoplantar pustulosis

Sternocostoclavicular hyperostosis is a rare syndrome that is characterized by hyperostosis and soft tissue ossification between the clavicles and the anterior part of the upper ribs. This syndrome frequently is found in the case of palmoplantar pustulosis (PPP), especially in Japan. There have been few published reports, however, of Tc-99m MDP bone imaging findings in PPP. Eleven patients with PPP who were suspected to have sternocostoclavicular hyperostosis were studied with Tc-99m MDP whole body bone imaging. Bone images were abnormal in 11 patients. Abnormal radionuclide concentrations were observed in the sternoclavicular, sternocostal, and manubriosternal joints, in the ribs, and in the sternum. Whole body imaging revealed radionuclide accumulations unexpectedly in other bones such as the vertebrae, femur, tibia, or sacroiliac joints in five of 11 cases. Radiographs were available in nine patients. Three chest radiographs were negative, and six showed various degrees of hyperostosis or sclerotic changes in sternoclavicular, sternocostal, or manubriosternal joints, or in the sternum or anterior upper ribs. These bone lesions usually were more prominent and more easily recognized with bone scintigraphy. Bone scintigraphy should be used as a routine procedure in patients with PPP who are suspected to have sternocostoclavicular hyperostosis.     

Intrathoracic and intra-abdominal Tl-201 abnormalities seen on rotating raw cine data on dual radionuclide myocardial perfusion and gated SPECT.

PURPOSE: The lower thorax and upper abdomen are visualized during cardiac acquisition of rest Tl-201 and stress Tc-99m tetrofosmin gated SPECT. Thus, abnormal Tl-201 localization in these areas and in organs such as parts of the lungs, liver, spleen, and kidneys can be observed, including rotating raw cine data. MATERIALS AND METHODS: Other than cardiac images, the authors retrospectively reviewed Tl-201 rotating (raw data) images of 235 patients. Abnormal findings in the lungs, liver, spleen, and kidneys were identified that correlated with the patients' clinical information; radiographic findings, including computed tomography and ultrasonography of the abdomen; other scintigraphic studies; and laboratory findings. RESULTS: In 53 patients, 54 abnormalities were detected. Intrathoracic abnormalities included focal areas of increased uptake, one in the right lower lung and another in the right upper lung that confirmed lung cancer, in 2 patients; diffuse uptake in both lungs in 11 patients; photopenia in the lung bases, which had resulted from pleural effusions, in 3 patients; and abnormal right liver configuration caused by elevation of the right hemidiaphragm in 1 patient. Of the intra-abdominal abnormalities, 12 patients with splenomegaly were identified. Six patients had focal areas of increased uptake in the gastric area. Nonvisualization of one kidney resulted from a congenitally absent right kidney in 1 patient, from right nephrectomy in 1 patient, from end-stage renal disease in another, and from a lower position of the left or right kidneys in 5 patients. Small and decreased uptake of both kidneys resulted from end-stage renal disease in 1 patient. Small and decreased uptake of one kidney was noted in 1 patient with renal scarring, in 1 patient with a renal stone, in 3 patients with chronic pyelonephritis, and in 5 patients with renal cyst(s). CONCLUSIONS: Discernible intrathoracic and intra-abdominal abnormalities using rotating raw cine data from imaging in three-dimensional displays include diffuse or focal pulmonary uptake, pleural effusion, elevation of a hemidiaphragm, splenomegaly, increased uptake in the gastric area, renal abnormalities including absent or small kidneys, end-stage renal disease, renal scarring, renal cyst(s), and lower position of a kidney. The incidental finding of such abnormalities may prompt further clinical investigation.     

Diffusely increased uptake by thoracic vertebrae on bone scintigraphy in midcourse of lung cancer irradiation: a case report

Bone scintigraphy performed on a patient during the middle of radiation therapy for an inoperable left lung malignancy showed diffusely increased uptake in the thoracic vertebrae and relatively increased uptake in the ribs of the left thorax. This bone scan finding is apparently a transient phenomenon that occurs in response to irradiation and eventually leads to photon deficiency or photopenia of the vertebrae. However, this transiently increased uptake of the thoracic spine, compared with uptake in the lumbar spine, mimics diffusely decreased uptake or photopenia of the lumbar vertebrae and may be misinterpreted as an effect of irradiation of the abdominal region. In the case of asymmetric uptake between the thoracic and lumbar spine, a carefully taken history of the timing and location of irradiation is necessary to avoid misinterpretation.     

Pathologic hepatic Tc-99m-MDP uptake in polyostotic fibrous dysplasia

Fibrous dysplasia of bone is a congenital, sporadic developmental disorder characterized by immature fibrous connective tissue and bone deformities. Hepatic Tc-99m-MDP uptake is a rare, serendipitous finding during bone scanning studies. The present patient was a 25-year-old male who had severe polyostotic fibrous dysplasia. On Tc-99m-MDP (methylene diphosphonate) bone scintigraphy, increased activity accumulations were seen on multiple ribs, vertebrae and base of the cranium. In addition, diffuse increased pathologic uptake of Tc-99m-MDP in the liver was shown. Intravenous pamidronate was administered monthly for two months. In the third week of the last administration Tc-99m-MDP bone scintigraphy was performed again, but despite sustained bone involvement, pathologic hepatic uptake was not seen on the scan. We thought that pathologic hepatic Tc-99m-MDP accumulation, may be related to the formation and aggregation of calcium oxalate and phosphate crystals which improved with pamidromat treatment.     

Ectopic parathyroid adenoma with Tc-99m MIBI washout: role of SPECT

The authors present a case of a 71-year-old woman with clinical and biochemical features of primary hyperparathyroidism and a history of right pneumonectomy. An ultrasound scan did not demonstrate any abnormality. A planar Tc-99m methoxyisobutylisonitrile (Tc-99m MIBI) scan showed an area of minimally increased uptake within the right hemithorax. However, unlike most adenomas, this demonstrated washout similar to the thyroid at 90 minutes and 3 hours. Subsequent SPECT imaging clearly showed the lesion in the superior right hemithorax. A CT scan and angiogram confirmed the presence of this mass. After surgery, histology confirmed the diagnosis of a parathyroid adenoma. Postoperatively, the calcium and PTH levels returned to normal.     

Skull base involvement by a nasopharyngeal carcinoma shown by Tc-99m MDP SPECT but not by computed tomography

PURPOSE: Plain radiographs, computed tomography (CT), and more recently magnetic resonance imaging (MRI) are used routinely to stage carcinoma of the nasopharynx. Tc-99m methylene diphosphonate (MDP) SPECT is seldom used for local staging of the disease. MATERIALS AND METHODS: Plain radiographs and CT were used to stage squamous carcinoma of the nasopharynx in a 50-year-old man with a left XII nerve palsy. RESULTS: Findings of the plain radiographs were normal, whereas the CT scan revealed a nonhomogenous hyperdense mass in the nasopharynx but intact underlying bone. Given the symptoms, a Tc-99m MDP planar scan was ordered and showed no enhanced uptake, but SPECT images obtained at the same time revealed markedly increased focal radiotracer uptake in the region of the tumor, indicating osseous involvement. CONCLUSION: Possible bony invasion with a nasopharyngeal carcinoma may be better shown with MDP SPECT than with planar isotope bone scans, plain radiographs, or CT.     

Tc-99m MIBI scintigraphy in tall cell variant of papillary thyroid carcinoma with negative radioiodine scan

We report on a 45-year-old man who had a mass on the wall of the anterior right hemithorax. An excisional biopsy indicated carcinoma metastasis from thyroid malignancy. Tc-99m methoxyisobutyl isonitrile (MIBI) scintigraphy revealed markedly increased activity on the left side of the thyroid and the thoracic wall mass. Postoperative histology revealed a tall cell variant of papillary thyroid carcinoma. Whole body scintigraphy after radioiodine treatment was negative twice. However, Tc-99m MIBI and bone scintigraphy showed multiple soft tissue and bone metastases in the follow-up period. He died 3 years later because of complications of distant lung metastases.     

低剂量螺旋CT胸部健康体检价值的探讨

目的:探讨低剂量螺旋CT对胸部健康体检的价值。方法:采用低剂量螺旋CT对1 953例参加健康体检者行胸部扫描,观察肺部、心血管、胸壁(软组织、骨骼)及上腹部的病变。结果:1953例被检者,304例检出肺内非钙化结节,其中21例诊断为肺癌,早期肺癌20例(95%);全部被检者冠状动脉钙化阳性者275例,阳性率为14.1%;胸主动脉钙化阳性者371例,阳性率为19.0%;胸椎骨质增生56例,胸椎压缩骨折8例;乳腺癌1例;脂肪肝23例,肝囊肿10例。结论:采用低剂量螺旋CT胸部体检,不仅可以检出早期肺癌,还可以检出冠状动脉和主动脉钙化斑块、胸壁病变及上腹部病变。一次胸部CT筛查可以检出多脏器具有临床价值的疾病。     

Brain perfusion SPECT in neuro-Behçet’s disease: Discordance between Tc-99m-HMPAO and Tc-99m-ECD

A patient with neuro-Behçet’s disease was studied with both Tc-99m-HMPAO and Tc-99m-ECD brain perfusion SPECT during the same time period. In Tc-99m-HMPAO SPECT, focal high uptake was observed in the left basal ganglia where MRI depicted abnormal signal intensity. Conversely, Tc-99m-ECD SPECT did not show corresponding high uptake, but demonstrated rather low uptake in contrast to the Tc-99m-HMPAO SPECT. This case suggests that Tc-99m-HMPAO and Tc-99m-ECD may show discordant distribution in inflammatory brain disease such as neuro-Behçet’s disease.     

Atypical Paget's disease with quantitative assessment of tracer kinetics

INTRODUCTION: Paget's disease of bone is characterized by alterations in skeletal metabolism, affecting a single or multiple bones. Paget's is usually confined to an individual bone and typically does not spread or extend across joints. A patient with an unusual pattern of disease is presented together with quantitative assessment of the tracer kinetics pre- and posttreatment. MATERIAL AND METHODS: A 75-year-old lady patient presented to her general practitioner in May 2002 with a history of lethargy. Clinical examination was unremarkable and further investigations such as blood tests (alkaline phosphatase levels), Tc-99m MDP bone scan, biopsy, and CT scan were carried out. RESULTS: Alkaline phosphatase levels were greater than 2000 IU/L (Normal: 31-116 IU/L). The Tc-99m MDP bone scan showed strikingly increased uptake in the central skeleton involving the thoracic vertebrae and the adjoining ribs. The bone biopsy was inconclusive. CT scan revealed symmetrical expansion of the ribs with bridging osteophytes across the ribs and spine. The patient was treated with risedronate and quantitative analysis of the pre- and posttherapy bone scans showed reduced plasma clearance in the pagetic bones. CONCLUSIONS: This case illustrates an unusual distribution of bone lesions in Paget's disease, which we think could be due to the result of degenerative disease leading to bridging and allowing direct extension of disease from one bone to another.     

Potential false positive Tc-99m sestamibi parathyroid study due to uptake in brown adipose tissue

We report on a 55-year-old woman with suspected primary hyperparathyroidism who underwent dual phase Tc-99m sestamibi parathyroid imaging. Symmetric, patchy activity in the neck and shoulders was localized to low attenuation areas on integrated SPECT/CT and attributed to uptake in brown adipose tissue (BAT). Focal uptake in the anterior thorax on SPECT images, which potentially may have been misinterpreted as ectopic parathyroid tissue, was demonstrated on SPECT/CT as uptake in BAT. Recognition of this pattern on parathyroid SPECT/CT scintigraphy may avoid false positive reports. Our case provides further evidence that in addition to F-18 FDG, I-123 MIBG, and Tc-99m tetrofosmin, Tc-99m sestamibi may also accumulate in BAT.     

Lung uptake on a bone scan: a case of pulmonary Waldenstrom's macroglobulinemia

Pulmonary involvement secondary to Waldenstrom's macroglobulinemia (WMG) is described in a 40-year-old male by incidental findings on a bone scan. He was examined for right leg pain, and bone scan revealed unexpected pulmonary uptake of Tc-99m MDP. CT scan of the thorax revealed pleural effusion and slightly disseminated micronoduler density increase in the right lung and parenchymal infiltration in the left lung. Transdermal lung biopsy demonstrated diffuse infiltration of lymphoplasmocytoids. Reporting the presence of pulmonary involvement is important because it may prevent morbidity from pulmonary dysfunction.     

Simultaneous assessment of right ventricular function and hypertrophy by Tc-99m MIBI

PURPOSE: Tc-99m MIBI allows the simultaneous performance of cardiac blood pool scintigraphy and myocardial SPECT. The authors performed studies to determine whether right ventricular function and hypertrophy can be evaluated simultaneously using Tc-99m MIBI in patients with right heart disease. METHODS: Using right heart catheterization, several parameters of pulmonary circulation were measured, including right ventricular ejection fraction, in 23 patients with chronic pulmonary disease and pulmonary vascular disease. Within 1 week, right heart blood pool scintigraphy was performed using the first-pass method using Tc-99m MIBI. The right ventricular ejection fraction calculated from right heart blood pool scintigraphy was compared with that measured using right heart catheterization. Myocardial SPECT was performed 1 hour after right heart blood pool scintigraphy. On the short axis images, which allowed optimal visualization of the right ventricle, the right and left ventricular free walls were established as regions of interest. Myocardial wall counts were determined. The right ventricular uptake: left ventricular uptake ratio was calculated to study the relation of that ratio to mean pulmonary artery pressure and total pulmonary resistance. RESULTS: A significant correlation was observed between the right ventricular ejection fraction calculated on right heart catheterization and that calculated on right heart blood pool scintigraphy. The right ventricular uptake:left ventricular uptake ratio correlated positively with pulmonary artery pressure and total pulmonary resistance. CONCLUSION: These results suggest that Tc-99m MIBI allows simultaneous noninvasive evaluation of cardiac function and structure, which previously was considered impossible in patients with right heart disease.     

Diffuse thoracoabdominal radioactivity seen in bone imaging

Diffusely increased radioactivity in the thoracoabdominal region (lower thorax and/or upper abdomen) occasionally has been observed when performing Tc-99m phosphonate bone studies. To assess the significance of activity in this finding, 1100 bone scintigrams were reviewed and the clinical data and other diagnostic imaging procedures were evaluated in these cases. With the exclusion of Tc-99m sulfur colloid liver-spleen scans 18 patients were found to have mild but diffuse increased radioactivity in the thoracoabdominal region either on the right or left. Clinical findings in these cases with abnormal uptakes were pleural effusions (six cases), hepatic colonic metastases (six cases), splenic metastases from bronchogenic carcinoma (one case), abdominal and peritoneal colonic metastases (one case), a massive metastatic squamous cell carcinoma (from lung) in the right lower chest (one case), and defective radiopharmaceuticals (three cases). Since the defective radiopharmaceuticals contained 5% of hydrolyzed reduced Tc-99m colloid by thin-layer chromatography, each of three patients received approximately 740 mu Ci of Tc-99m sulfur colloid. Factors to be considered in the interpretation of diffuse thoraco-abdominal activity from a bone agent should include splenic or hepatic metastases, a Tc-99m sulfur colloid splenic or hepatic metastases, a Tc-99m sulfur colloid study within the previous 24 hours, pleural effusion, faulty radiopharmaceuticals, and abdominal and peritoneal colonic metastases.     

Diffuse Pulmonary Uptake of Tc-99m Methylene Diphosphonate in a Patient with Non-tuberculosis Mycobacterial Infection

Extra-osseous uptake of bone-seeking radiopharmaceuticals has been reported at various sites and it is known to be induced by various causes. Diffuse pulmonary infection, such as tuberculosis, can be a cause of lung uptake of bone-scan agent. Here we report on a patient with non-tuberculosis mycobacterial infection (NTM) who demonstrated diffuse pulmonary uptake on Tc-99m MDP bone scan. After medical treatment for NTM, the patient’s lung lesions improved. Extraskeletal lung Tc-99m MDP uptake on bone scan may suggest lung parenchymal damage associated with disease activity.