Testicular lymphoma with bone/bone marrow metastases illustrated by scrotal sonography, spinal MRI, and total body Tc-99m HMDP and Tc-99m MIBI imagines

An 83-year-old man with testicular lymphoma demonstrated progressive scrotal enlargement with non-homogeneity sonographically and abnormally increased uptake in the scrotum of Tc-99m HMDP and Tc-99m MIBI scintigraphically. Extensive bone/bone marrow metastases were exhibited by Tc-99m MIBI and Tc-99m HMDP scintigraphies and MRI of the spine. In addition, focal/tubular activity of the femoral bone marrow on Tc-99m MIBI imaging was consistent with skeletal scintigraphic findings. It is emphasized that Tc-99m MIBI total body imaging enabled the demonstration of testicular lymphoma as increased uptake and the illustration of skeletal/bone marrow metastases as diffuse and/or focal increased uptake, especially focal/tubular MIBI activity of the femoral marrow.     

Tc-99m HMDP (hydroxymethylene diphosphonate): a radiopharmaceutical for skeletal and acute myocardial infarct imaging. I. Synthesis and distribution in animals

Technetium-99m hydroxymethylene diphosphonate (Tc-99M HMDP) is a new diphosphonate skeletal imaging agent. Animal studies show that Tc-99m HMDP has a higher uptake on bone and a more rapid clearance from the blood than any of the three technetium-labeled bone imaging agents in current use: Tc-99m methylene diphosphonate (DMP), Tc-99 (1-hydroxyethylidene) diphosphonate (HEDP), and Tc-99m pyrophosphate (PPi). On the basis of these animal studies, Tc-99m HMDP is a highly promising candidate for skeletal imaging.     

Ring appearance on Tc-99m MIBI thoracic SPECTs and increased uptake on Tc-99m HMDP thoracic SPECTs in a pulmonary mass of small cell carcinoma

Tc-99m MIBI is taken up avidly by viable tumor tissue and does not accumulate in the necrotic carcinoma. We present a patient who underwent Tc-99m MIBI and Tc-99m HMDP thoracic SPECTs: a large area of increased MIBI uptake with central photopenia (ring appearance) in the right upper lung localizes bone imaging agent and does not localize multiple areas of intense uptake in the metastatic hilar mediastinum lymph nodes. Rapid growth of tumor cells in the lung leading to central necrosis/ischemia accounts for bone imaging agent localization in the tumor, as well as the ring-appearance of lung mass on Tc-99m MIBI imaging. These findings may reflect less viability of the lung tumor as compared with intense MIBI uptake in hilar/mediastinal lymph node uptake without bone agent localization.     

Comparison of In-111 octreotide and Tc-99m (V) DMSA scintigraphy in the detection of medullary thyroid tumor foci in patients with elevated levels of tumor markers after surgery.

PURPOSE: In this retrospective study, the authors evaluated the utility of In-111 octreotide (OctreoScan) and Tc-99m (V) DMSA scintigraphy for the localization of recurrent metastatic tumor foci in patients with medullary thyroid cancer (MTC) and compared the findings with those of conventional radiologic imaging methods. METHODS: The scintigraphic images were compared with computed tomography (CT) and magnetic resonance imaging (MRI) and ultrasonography (US) in 14 patients (8 men, 6 women; age range, 22 to 74 years) with elevated calcitonin and carcinoembryonic antigen levels after total thyroidectomy. All scintigraphic image findings were evaluated qualitatively as mild uptake (+) and moderate to marked uptake (++). RESULTS: In-111 octreotide may be superior to Tc-99m (V) DMSA for the detection of tumor foci of patients with MTC on a patient basis (78.5% versus 57.1%) and on a lesion basis (44.1% versus 30.2%). The sensitivity rate for In-111 octreotide (78.5%) was also similar to that of CT and MRI on a patient basis. Conversely, the combined use of Tc-99m (V) DMSA and In-111 octreotide revealed the best sensitivity rate (85.7%) on a patient basis, whereas the combined use of CT and MRI showed the best sensitivity rate (81.3%) on a lesion basis. CONCLUSIONS: These findings suggest that In-111 octreotide is superior to Tc-99m (V) DMSA and has a similar sensitivity rate to CT and MRI for the diagnosis of recurrent or metastatic MTC. Although the combined use of In-111 octreotide and Tc-99m (V) DMSA was most sensitive, the combined use of CT and MRI with radionuclide imaging methods may better detect more metastatic tumor foci.     

Tc-99m hydroxymethylene diphosphonate and Tc-99m methylene diphosphonate: biological and clinical comparison: concise communication

The biologic and imaging characteristics of Tc-99m HMDP and Tc-99m MDP were compared in ten patients. Tc-99m HMDP blood levels were marginally lower at 4 hr. There were no significant differences in 4-hr urinary clearance, normal bone-to-background ratio, or ratio of lesion to normal bone. Relative image quality comparison showed a slight preference for Tc-99m HMDP. Biologically Tc-99m HMDP compares favorably with Tc-99m MDP. Under the conditions of this study, Tc-99m HMDP image quality is at least comparable to that of Tc-99m MDP.     

Osteoblastic osteosarcoma of the mandible: findings on Tc-99m HMDP bone and Ga-67 citrate scintigraphy

A 25-year-old woman presented with a disturbance in the opening of her mouth 5 months before admission. On admission, painful swelling of the right preauricular region was revealed. Computed tomography (CT) demonstrated a soft tissue density mass around the right condylar process of the mandible. Tc-99m hydroxymethylene diphosphonate (HMDP) bone scintigraphy and Ga-67 citrate scintigraphy showed avid uptake in the mass. The tumor was histologically identified as an osteoblastic osteosarcoma of the right mandible. There are few reports of Ga-67 citrate scintigraphy findings of osteoblastic osteosarcoma of the mandible. The accumulation patterns on Tc-99m HMDP bone scintigraphy and Ga-67 citrate scintigraphy are possibly characteristic of osteoblastic osteosarcoma of the mandible.     

Scintigraphic findings in congenital lipodystrophy

The scintigraphic findings of a patient with characteristic clinical, laboratory, and radiographic features of congenital lipodystrophy were studied. Bone scan showed uniform increased bone uptake of Tc-99m MDP with markedly enhanced peri-articular activity and very prominent renal activity. Liver-spleen scan showed marked hepatosplenomegaly. This combination of scintigraphic abnormalities is unique in congenital lipodystrophy and constitutes a very interesting constellation of findings. Observed scintigraphic findings are compatible with previously described radiographic findings.     

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.     

External and biopsy determination of preoperative Tc-99m MDP femoral-head labeling in fracture of the femoral neck: concise communication

In 30 fresh fractures of the femoral neck, the preoperative femoral-head tracer uptake in Tc-99m MDP scintimetry was compared with the uptake of peroperatively obtained femoral-head biopsies and correlated to intravital bone staining by tetracycline, infused concurrently. Bone uptakes of Tc-99m MDP and tetracycline were shown to correlate well. Total absence of Tc-99m MDP uptake in the femoral-head biopsy corresponded to a scintigraphic uptake ratio of 0.7 (fractured over contralateral head), whereas a normal Tc-99m MDP biopsy uptake corresponded to a ratio of 1.5. This suggests that in Tc-99m MDP scintimetry of a normal hip, less than half of the emission ascribed to the femoral head is derived from the femoral head itself.     

Discordant uptake of technetium-99m DISIDA and technetium-99m sulfur colloid in an amebic abscess

Hepatobiliary imaging in a patient with an amebic abscess showed an early cold defect that later showed rim enhancement. A Tc-99m SC scan did not show prominent flow (making hepatoma unlikely) and showed the previously noted defect to appear larger and without rim enhancement. The differential damage to Kupffer cells and hepatocytes or edema may account for these findings. Amebic abscess should be included in the differential diagnosis of lesions that give increased Tc-99m IDA but cold Tc-99m SC images.     

Reverse of the differential uptake intensity of Tc-99m MIBI and Tc-99m V-DMSA by multiple myeloma lesions in response to therapy

PURPOSE: The objective of this study was to compare the uptake changes of Tc-99m 2-methoxy isobutyl isonitrile (MIBI) and Tc-99m pentavalent dimercaptosuccinic acid (V-DMSA) in multiple myeloma (MM) lesions in response to high-dose chemotherapy (HDC). MATERIALS AND METHODS: The authors compared Tc-99m MIBI and Tc-99m V-DMSA scans before and after HDC in a patient with focal MM lesions without amyloidosis who had received previous standard chemotherapy as well. RESULTS: HDC had the effect of eliminating all Tc-99m MIBI uptake in the lesions. Tc-99m V-DMSA uptake was increased in lesions presenting significant initial Tc-99m MIBI uptake. In 1 particular lesion that demonstrated this phenomenon, magnetic resonance showed necrosis of the area of MM. CONCLUSION: The authors consider that the effect of increasing Tc-99m V-DMSA uptake in the absence of an increase in viable plasma cells possibly reflects the treatment-generated inflammatory and fibrotic changes and not necessarily viable tumor tissue. Exclusive focal Tc-99m V-DMSA uptake in this clinical setting could be considered as a sign of effectively treated lesions and not a sign of deterioration.     

Tl-201 and Tc-99m HMDP scintigraphic findings in extraskeletal osteosarcoma

Extraskeletal osteosarcoma is an extremely rare high-grade malignant soft tissue tumor, which accounts for approximately 4% of osteosarcomas and less than 1% of all soft tissue sarcomas. There have been reports describing the scintigraphic findings of this tumor, especially with Tl-201. We report a biopsy-proven case of extraskeletal osteosarcoma in which the bone and thallium scans were found to be useful in monitoring chemotherapy response. The Tc-99m HMDP bone scan revealed increased extraskeletal uptake in the tumor.     

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.     

Scintigraphic findings in infantile hemangioendothelioma

The scintigraphic findings on sulfur colloid liver-spleen imaging, Tc-99m labeled RBC blood pool imaging, and Tc-99m MDP bone imaging in four patients with infantile hemangioendothelioma are described. Thirteen radionuclide studies were performed, with serial sulfur colloid images obtained in three patients, allowing interval assessment of liver size and tumor involvement. Findings of Tc-99m MDP uptake in the livers of two patients with hemangioendothelioma and diffuse increase in hepatic RBC labeled blood pool activity in one patient also are reported.     

Incidental vertebral lesions identified during technetium-99m sulfur colloid liver-spleen imaging

Three vertebral lesions, two compression fractures, and one metastasis in two patients, were incidentally demonstrated during Tc-99m sulfur colloid liver-spleen studies. Although the scintigraphic photon-deficient area could not be differentiated due to the metastasis and the compression fracture, the abnormal radiocolloid findings of vertebrae may lead to further studies using Tc-99m diphosphonate, Ga-67, radiographic studies, and/or biopsy.     

Scintigraphic findings mimicking focal nodular hyperplasia in a case of hepatoblastoma.

Hepatoblastoma is a primary liver neoplasm in which prompt diagnosis and resection are critical to long-term survival. Liver scintigraphy using Tc-99m sulfur colloid and Tc-99m iminodiacetic acid (IDA) derivatives has been used in the evaluation of hepatic masses. Most space-occupying lesions of the liver appear as photopenic regions following either Tc-99m SC or IDA agents. Two exceptions have been reported. Focal nodular hyperplasia (FNH) has been shown to have variable colloid uptake, which is dependent upon the number of Kupffer cells per given volume. Many patients with FNH will demonstrate activity within the FNH to be greater or equal to the normal liver. In addition, two cases of hepatoblastoma have been reported to show colloid activity within the tumor, and in one patient slight uptake of Tc-99m IDA was noted in the tumor 15 minutes postinjection. The current case demonstrates a hepatoblastoma in which the scintigraphic findings with Tc-99m SC and Tc-99m IDA were similar to those reported, with retention of IDA far greater than the previously reported case.     

Splenic accumulation of Tc-99m HMDP in a patient with severe alcoholic cirrhosis of the liver

The authors report unusual splenic accumulation of Tc-99m hydroxymethylene diphosphonate (HMDP) on bone scintigraphy of a patient with alcoholic cirrhosis of the liver. Laboratory studies showed hemolytic anemia and hemochromatosis resulting from alcohol abuse, both of which are thought to be related to the diffuse splenic uptake observed. When diffuse splenic accumulation by Tc-99m HMDP is seen, the existence of alcoholic hepatopathy might be considered.     

Bone and gallium scintigraphy in sacral chordoma. Report of four cases.

Bone scintigraphy with Tc-99m HMDP and gallium scintigraphy were evaluated in four patients with a primary sacrococcygeal chordoma. All lesions showed a photon-deficient or cold lesion corresponding to the tumor on bone scintigraphy, with no abnormal accumulation clearly observed on gallium scintigraphy. These findings led the authors to conclude that a midline sacrococcygeal tumor showing reduced uptake or a cold lesion on bone scintigraphy and no increased accumulation on gallium scintigraphy could be a chordoma rather than the malignant neoplasm suspected in this region.     

Tc-99m exametazime-labeled leukocyte scans in the study of infections in skull neurosurgery

Diagnosis and follow-up of skull infections are usually performed by neurologic examination, laboratory tests and instrumental diagnostic methods such as computed tomography (CT) and magnetic resonance imaging (MRI). These have, however, shown some limitations for specificity. The aim of the current study was to evaluate the overall contribution of Tc-99m exametazime-labeled leukocyte imaging scan Tc-99m hexamethylpropyleneamine (HMPAO) labeled white blood cells (WBC) in the diagnosis and management of infections in skull neurosurgery. Thirty-four patients were subdivided into 4 groups on the basis of the suspected pathology: intracerebral lesions on CT or MRI (group A, n = 20), suspected postsurgical infections (group B, n = 6), suspected deep infection of the surgical wound (group C, n = 4), and suspected infection of the ventriculoperitoneal shunt (group D, n = 4). All patients underwent CT, MRI, and Tc-99m HMPAO WBC imaging. Patients in group C also underwent bacteriologic and culture examinations of wound secretions if present. In positive cases in group A, Tc-99m HMPAO WBC imaging was repeated. The scintigraphic results were compared with histologic findings in patients who underwent surgery and with the results of a 12-month clinical follow-up in the remaining patients. Tc-99m HMPAO WBC scans correctly detected the infections in all groups. Furthermore, such imaging proved to be able to document recovery from the disease in all of the assessed cerebral abscesses. This study may have an important role both in the diagnosis and in the management of infections in skull neurosurgery, which, it is hoped, will be confirmed in the future.     

Comparison of Tc-99m sestamibi and TI-201 uptake in multiple myeloma

The authors report abnormal Tc-99m sestamibi (MIBI) and TI-201 uptake in a 62-year-old patient with histologically and biochemically proved myeloma. TI-201 imaging was undertaken for tumor evaluation, and 3 days later a Tc-99m MIBI study showed diffuse and focal marrow uptake with focal skull lesions, whereas TI-201 did not show skull lesions. After treatment, follow-up Tc-99m MIBI whole-body imaging was performed and the marrow uptake was decreased.