Tc-99m(V) DMSA imaging. A new approach to studying metastases from breast carcinoma.

Combined Tc-99m MDP skeletal imaging and Tc-99m(V) DMSA whole body scans to detect metastases were performed during the follow-up of 30 patients who underwent surgery for breast carcinoma. Eight patients had normal Tc-99m MDP and Tc-99m(V) DMSA scans and were declared free of metastatic disease, further confirmed by no change in symptomatology over a 1-year follow-up period. Twenty-two patients had positive Tc-99m MDP scans with varied skeletal involvement. Tc-99m(V) DMSA scans showed matched areas of increased radiotracer concentration in bony metastases in 20 of these patients. Tc-99m(V) DMSA concentration was not seen in traumatic vertebral collapse or in coexistent osteoarthritic disease in vertebral metastatic involvement. Interestingly, Tc-99m(V) DMSA showed increased concentration in brain and liver metastases. Pentavalent Tc-99m(V) DMSA appears useful for detecting skeletal and soft-tissue metastases in breast carcinoma, and can improve the specificity of Tc-99m MDP bone scans in screening for bone metastases.     

Technetium-99m MDP vs technetium-99m dicarboxypropane diphosphonate. A clinical comparison in various pathologic conditions

The performance of Tc-99m MDP vs Tc-99m dicarboxypropane diphosphonate (DPD) was evaluated in 20 patients with various skeletal bone diseases. Each patient was investigated twice, with an interval of three days between studies and using the same protocol, hence each case served as its own control. The results were: In a subjective interpretation by five independent and experienced investigators, the difference between agents was small, yet in favor of MDP. Region of interest (ROI) analysis of the pooled results in 74.4% of all cases shows a higher bone lesion to normal bone ratio (BL/NB), and in 79.3% of all cases, a better bone lesion to soft tissue ratio (BL/ST) with Tc-99m MDP. When considering pathology types separately, the BL/NB ratio of Tc-99m MDP was 17.7% higher than the one of Tc-99m DPD in metastases, 9.5% higher in rheumatoid arthritis, 2.8% higher in metabolic diseases, and 24% higher in bone fractures. Student's paired t test on the pooled BL/NB ratios shows a difference of 15.5% for Tc-99m MDP, significant at P = 0.00155. The overall results of our study favor Tc-99m MDP.     

Increased liver and spleen accumulation of Tc-99m methylene diphosphonate associated with intravenous injection of MRI contrast gadolinium-diethylenetriaminepentaacetic acid

Several conditions that can cause diffuse hepatic or splenic uptake of Tc-99m methylene diphosphonate (Tc-99m MDP) have been previously reported. Nevertheless, diffuse abnormal liver and spleen uptake of Tc-99m MDP associated with intravenous injection of magnetic resonance imaging contrast gadolinium-diethylenetriaminepentaacetic acid is not previously known. In our series, we reported diffuse increased Tc-99m MDP activity in the liver and spleen in bone scans in patients who received Tc-99m MDP injection shortly after contrast-enhanced magnetic resonance imaging.     

Diffuse hepatic and splenic uptake of Tc-99m methylene diphosphonate on bone scintigraphy after intravenous administration of gadolinium-containing MRI contrast

Three patients with known lung cancer came on different days to our department to have a bone scan to evaluate possible osseous metastatic disease. The bone scan images showed increased Tc-99m methylene diphosphonate (Tc-99m MDP) activity in the liver and to a lesser degree in the spleen, whereas bone scan images from other patients on the same days showed no abnormal activity in the liver or spleen. On the same day, shortly before the bone scan, all 3 patients had a magnetic resonance imaging scan with an intravenous injection of Magnevist (Gadolinium-DTPA), which was not previously known to cause an altered Tc-99m MDP distribution. In the follow-up bone scans performed within 1 week of the initial bone scintigraphy, images from none of these 3 patients showed abnormal liver or spleen activity. The findings indicated that the increased Tc-99m MDP activity in the liver and spleen in the early studies was indeed an effect of Gadolinium-containing magnetic resonance imaging contrast. This effect was further confirmed by an animal experiment.     

Focal uptake of Tc-99m MDP in a gossypiboma

A 51-year-old Korean woman with a history of breast cancer underwent screening bone scintigraphy, which revealed minimal soft tissue uptake of Tc-99m methylene diphosphonate (MDP) in the right lower quadrant. CT and plain films confirmed that the uptake was due to a retained surgical sponge or gossypiboma. The incidence of gossypibomas has been reported at high as 1 in 1000 to 15,000 intra-abdominal operations. The natural progression of an aseptic gossypiboma is a foreign body reaction and granuloma formation. This inflammatory granulomatous reaction is the most likely cause of the extraosseous accumulation of Tc-99m MDP. This entity should be added to the already extensive list of etiologies of extraosseous MDP accumulation.     

Tl-201 uptake in brown tumors of hyperparathyroidism.

Tl-201 chloride bone scans were performed on nine patients with primary hyperparathyroidism just after Tl-201 and Tc-99m parathyroid subtraction scintigraphy. Bone lesions accumulate Tl-201, especially in sites of brown tumor formation. This was proven by the histopathologic examination of two patients. Eight patients had bone scans with Tc-99m MDP. The lesion-to-background ratio was quantified in seven patients for Tl-201 and in four patients for Tc-99m MDP. Tl-201 uptake of the lesions were quantified in two patients. The lesion-to-background ratio was 1.63 +/- 0.21 and 2.51 +/- 0.88 for Tl-201 and Tc-99m MDP, respectively. A Ga-67 citrate scan was performed on one patient, and the lesion-to-background ratio was 1.49 +/- 0.06. The accumulation of Tl-201 in brown tumors of bone might be due to increased blood flow and local metabolic activity. Tl-201 chloride was inferior to Tc-99m MDP in lesion detection. It is concluded that bone imaging with Tl-201 can easily be performed following parathyroid subtraction scintigraphy to delineate the sites of brown tumor formation.     

Utility of 24 hour bone scan in evaluation of bone involvement by soft tissue sarcoma

Accumulation of Tc-99m MDP in soft tissue malignancies occurs frequently. When tumor overlaps adjacent bone structures, the bone margins can be indiscernible on a regular bone scan. Additional views should be taken to differentiate bone from tumor, however, separation is sometimes difficult and not always successful. This report presents a patient in whom accumulation of Tc-99m MDP in a liposarcoma of the thigh disappeared on a 24 hour scan and bone margins were seen clearly. A possible mechanism for this phenomenon and its utility are discussed.     

Comparison of Tc-99m MDP, Tc-99m HSA and Tc-99m HIG uptake in rheumatoid arthritis and its variants

Tc-99m polyclonal immunoglobulin-G has been shown to be a successful agent in the depiction of active inflammation in rheumatoid arthritis (RA). The objective of this study was to compare the uptake behaviors of Tc-99m HIG and Tc-99m MDP in RA and variants of rheumatoid arthritis (VRA). Seventeen patients with RA and 8 patients with VRA presenting with active inflammation were included in this study. Ten subjects with well-diagnosed degenerative joint disease constituted the control group. All joints in patients were also imaged with Tc-99m HSA to evaluate the vascularization status of the joints. Tc-99m HIG and HSA scans were obtained at 2, 4 and 24 hours after the injection of 555 MBq Tc-99m HIG and 296 MBq Tc-99m HSA. Conventional bone scans were performed 4 hours after the injection of 740 MBq Tc-99m MDP. Target-to-background (T/B) ratios were obtained exclusively over the joint regions. Tc-99m HIG T/B ratios of the active joints in RA were significantly higher than those of the non-active joints and the control group (p < 0.05). Tc-99m HIG T/B ratios in active joints showed a progressive increase between 2 and 24 hour images (p < 0.05). In contrast, Tc-99m HSA T/B ratios decreased in all active joints significantly (p < 0.05) except the ankle joint region (p > 0.05). The T/B ratios in Tc-99m MDP bone scans were higher in all active joints than in non-active RA joints and joints of controls but significantly differences were only detected in wrist and elbow joints. All clinically active joints in VRA patients accumulated Tc-99m HIG and HSA, and showed increased Tc-99m MDP uptake. These joints had a very similar Tc-99m HIG retention pattern to the RA joints. The detection rate of active joint inflammation with Tc-99m HIG was much higher than that with Tc-99m MDP. The increasing Tc-99m HIG uptake ratio between 2 and 24 hours in contrast to Tc-99m HSA indicates the presence of other binding mechanisms besides increased vascularity in RA.     

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.     

Pathologic fractures in a patient with renal osteodystrophy. Failure of early detection on bone scans

A case of false-negative Tc-99m MDP bone scintigrams, taken at one and two weeks for pathologic fractures in a patient with metabolic bone disease and a super-scan appearance, is described. The patient had renal osteodystrophy, and postparathyroidectomy hypocalcemia. Postoperative seizures caused multiple pathologic fractures. Initial scans were negative for focal tracer localization in the presence of a continued super-scan appearance. After months of calcium and vitamin D replacement therapy, fracture sites became positive on Tc-99m MDP imaging. The observations in this case lend credence to the hypothesis of Tc-99m MDP binding by immature collagen in the production of a super scan in metabolic bone disease, as well as that of Tc-99m MDP chemisorption to calcium hydroxyapatite crystal in fracture healing. In addition, aluminum toxicity, common in chronic renal osteodystrophy, may have played a role in the delayed fracture healing.     

Scintigraphic evaluation of calcinosis in juvenile dermatomyositis with Tc-99m MDP

Two children with juvenile dermatomyositis and extensive, debilitating soft tissue calcifications are described. Whole-body bone scans with Tc-99m MDP were performed in both cases before and during specific treatment for the calcinosis. Baseline studies showed marked tracer localization in the soft tissues and provided an objective baseline assessment of the extent of the soft tissue calcifications. Follow-up studies showed gradual clearance of the extraskeletal uptake and were useful in monitoring the therapeutic response. These cases show that skeletal scintigraphy can function as a useful auxiliary tool to evaluate calcinosis in children with juvenile dermatomyositis.     

Technetium-99m MDP imaging of acute radiation-induced inflammation

Tc-99m MDP three-phase bone imaging demonstrated the acute hyperemic inflammatory soft tissue phase of radiation injury to the hand in a patient receiving radiation therapy to bone lesions of multiple myeloma.     

Dichotomy between Tc-99m MDP bone scan and fluorine-18 fluorodeoxyglucose coincidence detection positron emission tomography in patients with non-Hodgkin's lymphoma

The authors report two cases of non-Hodgkin's lymphoma that were evaluated not only by conventional staging work-up but also additional Tc-99m MDP bone scans and fluorine-18 fluorodeoxyglucose (F-18 FDG) coincidence detection (CoDe) positron emission tomographic (PET) imaging. There were discordant results between the Tc-99m MDP bone scans and F-18 FDG CoDe PET. In the first case, the bone marrow biopsy was positive, and F-18 FDG CoDe PET was consistent with a malignancy, but the findings of the Tc-99m MDP bone scintiscan were negative. In the second case, the bone marrow biopsy was negative, but F-18 FDG CoDe PET revealed focal skeletal involvement, which improved markedly on the follow-up study after chemotherapy. If skeletal involvement has a focal distribution and is confined to the marrow cavity, both bone marrow biopsy and bone scintigraphy can be falsely negative. In this situation, F-18 FDG PET is useful and revealing.     

The comparison of dual phase Tc-99m MIBI and Tc-99m MDP scintimammography in the evaluation of breast masses: Preliminary report

The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI.     

Disappearing calvarium in Gorham disease: MR imaging characteristics with pathologic correlation

Gorham disease is a rare condition characterized by intraosseous neoplastic proliferation of hemangiomatous tissue with progressive, massive osteolysis. We present a pathologically proved case of Gorham disease that involved the left parietal bone in a 23-year-old man. Imaging studies including conventional radiography of the skull, CT, MR imaging, and Technetium-99 m (Tc-99 m) scintigraphy demonstrated a large skull defect without associated soft tissue mass over the left parietal skull. Contrast enhancement and increased isotope uptake along the margin of the defect were shown at gadolinium-enhanced T1-weighted MR imaging and Tc-99 m methylene diphosphate (Tc-99 m MDP) bone scintigraphy. Pathologic study revealed intraosseous angiomatosis at the periphery of the osteolytic skull lesion.     

Incidental detection of gastrointestinal stromal tumor by Tc-99m MDP bone scan

This case demonstrates extraosseous 99m-technetium methylene diphosphonate (Tc-99m MDP) accumulation from a gastrointestinal stromal tumor. A 75-year-old woman underwent a temporal bone CT for conductive hearing loss that showed sclerosis in the right occipital condyle. Follow-up Tc-99m MDP bone scan for osseous metastases instead showed a mass-like extraosseous accumulation of Tc-99m MDP in the anterior left upper quadrant. Differential diagnoses included gastric cancer, lymphoma, metastatic melanoma, systemic hypercalcemia, or heterotopic mesenteric ossification. Contrast CT showed a well-circumscribed mass arising from the stomach, and subsequent pathology confirmed gastrointestinal stromal tumor. These tumors rarely can contain osteoclast-like giant cells and should be considered for extraosseous Tc-99m MDP accumulation.     

Technetium-99m MDP demonstration of neoplastic lesions involving bone and adjacent soft tissue

Four patients are presented with malignant tumors involving both bone and adjacent soft tissue. In each of these neoplasms (two representing adenocarcinoma of the prostate, and one each of squamous cell carcinoma of lung and chondrosarcoma), the lesions were detected by accumulation of Tc-99m MDP. Involvement of both bone and soft tissue was confirmed by CT examination or surgery. It is probable that the lesions originated in bone and then extended to soft tissue.     

False-negative bone imaging due to etidronate disodium therapy

A 77-year-old man with prostate cancer was serially evaluated for bone metastases using Tc-99m methylene disphosphonate (Tc-99m MDP) both on and off treatment with etidronate disodium (EHDP). While the patient was receiving the medication only minimal bony uptake of the tracer was seen with the majority remaining in the soft tissues. The similarly structured EHDP probably saturated the binding sites that the radioactive MDP usually adheres to. Physicians should be aware of this interaction and may have to wait until the EHDP has been discontinued for several months before performing bone imaging on these patients.     

The role of Tc-99m MDP and Ga-67 citrate in predicting the cure of osteomyelitis

Twenty rabbits with chronic osteomyelitis of the tibia were treated for eight weeks and then scanned with Tc-99m MDP and Ga-67 citrate. All were sacrificed and bacteriologic cultures of the tibia were obtained. All rabbits had positive Tc-99m MDP scans at the end of treatment despite thirteen cures of osteomyelitis. Eight had negative gallium scans and negative cultures. Five of the twelve positive gallium scans had negative cultures, while seven had positive cultures. Tc-99m MDP alone is not sensitive enough to be useful in predicting the cure of osteomyelitis, and combining Tc-99m MDP and Ga-67 citrate scintigrams offers no additional information over the Ga-67 citrate scintigram alone in follow-up of osteomyelitis.     

Increased bone marrow uptake on Tc-99m DMSA scintigraphy in a patient with renal osteodystrophy

A 16-year-old male patient was evaluated with Tc-99m Diethylenetriamine-pentaacetic acid (DTPA) and Tc-99m 2–3 Dimercaptosuccinic acid (DMSA) scintigraphy for renal failure secondary to renal calculi. The uptake in the renal cortex was significantly decreased both on DMSA and DTPA studies. Uptake calculation on DMSA scintigraphy in the kidneys disclosed values of less than 5 %. The activity in the liver and bone was significantly increased. A bone scan performed with Tc-99m methylene diphosphonate (MDP) revealed increased bone uptake with decreased soft tissue activity. Findings on bone scan were compatible with super scan, most likely due to renal osteodystrophy. This case illustrates the altered biodistribution of Tc-99m DMSA and a shift of the radiopharmaceutical to the bone marrow which is mot likely related to colloid formation due to changes in mineral balance in patients with renal failure.