High-activity samarium-153-EDTMP therapy followed by autologous peripheral blood stem cell support in unresectable osteosarcoma

Purpose: Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. These patients may benefit from therapy with radiolabeled phosphonates. Patients and Methods: Six patients (three male, three female; seven to 41 years) with unresectable primary osteosarcoma (n = 3) or unresectable recurrent sites of osteosarcomas (n = 3) were treated with high-activity of Sm-153-EDTMP (150 MBq/kg BW). In all patients autologous peripheral blood stem cells had been collected before Sm-153-EDTMP therapy. Results: No immediate adverse reactions were observed in the patients. In one patient bone pain increased during the first 48 hrs after therapy. Three patients received pain relief. Autologous peripheral blood stem cell reinfusion was performed on day +12 to +27 in all patients to overcome potentially irreversible damage to the hematopoietic stem cells. In three patient external radiotherapy of the primary tumor site was performed after Sm-153-EDTMP therapy and in two of them polychemotherapy was continued. Thirty-six months later one of these patients is still free of progression. Two further patients are still alive. However, they have developed new metastases. The three patients who had no accompanying external radiotherapy, all died of disease progression five to 20 months after therapy. Conclusion: These preliminary results show that high-dose Sm-153-EDTMP therapy is feasible and warrants further evaluation of efficacy. The combination with external radiation and polychemotherapy seems to be most promising. Although osteosarcoma is believed to be relatively radioresistant, the total focal dose achieved may delay local progression or even achieve permanent local tumor control in patients with surgically inaccessible primary or relapsing tumors.

Verfahrensanweisung für die nuklear medizinische Wächter-Lymphknoten-Diagnostik

The authors present a procedure guideline for scintigraphic detection of sentinel lymph nodes in malignant melanoma and other skin tumours, in breast cancer, in head and neck cancer, and in prostate and penile carcinoma. Important goals of sentinel lymph node scintigraphy comprise reduction of the extent of surgery, lower postoperative morbidity and optimization of histopathological examination focussing on relevant lymph nodes. Sentinel lymph node scintigraphy itself does not diagnose tumorous lymph node involvement and is not indicated when lymph node metastases have been definitely diagnosed before sentinel lymph node scintigraphy. Procedures are compiled with the aim to reliably localise sentinel lymph nodes with a high detection rate typically in early tumour stages. Radiation exposure is low so that pregnancy is not a contraindication for sentinel lymph node scintigraphy. Even with high volumes of scintigraphic sentinel lymph node procedures surgeons, theatre staff and pathologists receive a radiation exposure < 1 mSv/year so that they do not require occupational radiation surveillance.

Influence of the injection technique on the false negative rate of SLNE in multifocal breast cancer

Aim: We investigated the influence of the injection technique on the false negative rate in identifying the sentinel lymph node in multifocal breast cancer. Patients, methods: 958 consecutive patients were divided into unifocal and multifocal breast cancer patients. The scintigrafic and intraoperative detection rate as well as the false negatives were calculated in relation to peritumoral or subareolar injection. Results: In all patients the scintigrafic and intraoperative detection rate exceeded 99%, except in patients with multifocal cancer, who were injected peritumorally. In this group the intraoperative detection rate declined to 96%. In patients with unifocal breast cancer the false negative rate was below 5%, independent of the injection technique. Multifocal breast cancer patients showed a significant dependence on the injection technique. The false negative rate was 26.3% in patients with peritumoral injection and 5.6% in those with subareolar injection. Conclusion: The results clearly demonstrate that in multifocal breast cancer a reliable detection of a SLN is impossible with the peritumoral injection technique. Subareolar injection seems to be a way to operate on multifocal breast cancer with SLNE, but the number of investigated patients is too low for statistic approval. So, prospective studies should be performed to validate these preliminary results before SLNE becomes routine in multifocal breast cancer.

Diagnostic value and therapeutic impact of 18F-FDG-PET/CT in differentiated thyroid cancer

The clinical significance of 18F-FDG-PET/CT in the follow-up of patients with differentiated thyroid carcinoma was evaluated and the results were compared with those of 18F-FDGPET, 131I-whole-body scintigraphy including SPECT/CT (WBS) and ultrasound. In addition, it was the aim to investigate the impact of 18F-FDG-PET/CT on the therapeutic management. Patients, methods: 327 patients (209 women, 118 men; mean age 53 ± 18 years) with differentiated thyroid cancer (242 papillary, 75 follicular, 6 mixed, 1 Hürthle cell and 3 poorly differentiated tumours) were analyzed retrospectively at four tertiary referral centres. 289 18F-FDG-PET/CT and 118 18F-FDG-PET studies were performed in these patients between 2007 and 2010. In addition, an overall clinical evaluation was performed, including cytology, histology, thyroglobulin level, ultrasound, WBS, and subsequent clinical course in order to compare the molecular imaging results. Finally, the change in therapeutic management due to findings of 18F-FDG-PET/CT was investigated. Results: The sensitivity of 18F-FDG-PET/CT was 92%, the specificity was 95%. Sensitivity and specificity of 18F-FDG-PET alone were 67% and 93%, respectively. WBS showed a sensitivity of 65% and a specificity of 94%. The corresponding values of ultrasound were 37% and 94%, respectively. The sensitivity of 18F-FDG-PET/CT in the group of patients with a negative WBS (n=194) amounted to 96%. When 18F-FDG-PET/CT and WBS were considered in combination, tumour tissue was missed in only 2 out of 133 patients; when 18F-FDG-PET and WBS were combined, tumour tissue was missed in 1 out of 24 patients. 18F-FDG-PET/CT resulted in management change in 43% (n=57/133) with a decision on surgical approach in 20% (n=27/133). Conclusions: 18F-FDG-PET/CT is superior to 18F-FDG-PET alone in patients with differentiated thyroid cancer and has a direct impact on the therapeutic management of patients with suspected local recurrence or metastases, particularly in those with negative WBS.

[Endovascular brachytherapy (EVBT) with Rhenium-188 for restenosis prophylaxis after angioplasty of infrainguinal lesions: early experience]

PURPOSE

Restenosis remains a major problem in percutaneous transluminal angioplasty (PTA) of peripheral arteries. The aim of this feasibility study was to evaluate the technical feasibility and safety of a new endovascular brachytherapy (EVBT) device with Rhenium-188 in restenosis prophylaxis of infrainguinal arteries.

MATERIALS AND METHODS

From March 2006 to April 2009, 52 patients with 71 infrainguinal arterial lesions were treated with Re-188 to prevent restenosis after PTA. 40 patients with 53 lesions (24 de-novo lesions and 29 restenoses) were reexamined (clinic, color-coded duplex ultrasound) after a mean follow-up period of 12.7 months (2.6 to 25.1 months). The liquid beta-emitter Re-188 was introduced to the target lesion via an EVBT certified PTA balloon and a tungsten applicator. After the calculated irradiation time, Re-188 was aspirated back into the tungsten applicator. A dose of 13 Gy was applied at a depth of 2 mm into the vessel wall.

RESULTS

After a mean follow-up of 12.7 months, the overall restenosis rate after Re-PTA was 15.1 % (8 / 53 lesions). The restenosis rate for de-novo lesions was 20.8 % (5 / 24) and 10.3 % for restenoses (3 / 29). In 4 patients reintervention was necessary (3 PTAs and 2 major amputations). No periprocedural complications were observed. No elevated radiation dose for the patient or the interventionalist was measured.

CONCLUSION

EVBT with a Re-188 filled balloon catheter was technically feasible and safe after PTA of infrainguinal arterial lesions with restenosis rates lower than expected compared to published results. Treatment of restenoses seems to be more effective than de-novo lesions.

Neoadjuvant chemotherapy affects staging of colorectal liver metastasis--a comparison of PET, CT and intraoperative ultrasound

PURPOSE

Surgery for colorectal liver metastasis facilitates long-term survival, and neoadjuvant chemotherapy improves resectability but may also alter staging accuracy. The aim of this study was to evaluate the effects of neoadjuvant chemotherapy on the efficacy of positron emission tomography (PET), PET-computed tomography (CT), CT and intraoperative ultrasound (IUS) in the detection of liver metastasis.

METHODS

Between January 2007 and January 2010, 34 patients with resectable colorectal liver metastasis were included in this retrospective analysis. Seventeen patients had received neoadjuvant chemotherapy. PET or PET-CT, CT or magnetic resonance imaging (MRI) and IUS were performed in all patients. Sensitivity, specificity, positive predictive value and negative predictive value were analysed. Histopathological examination of the resected specimens served as standard reference.

RESULTS

A total of 109 liver segments were resected, of which 50 showed no metastatic involvement (45.9%). For patients without systemic chemotherapy, sensitivities for PET, CT/MRI and IUS were 92%, 64% and 100% respectively as compared with 63%, 65% and 94% for patients after neoadjuvant chemotherapy in a segment-based analysis. For PET, standardised uptake values were decreased by 3.9 in 10 patients after chemotherapy whereas lesion diameters were similar (3.0 vs. 3.2 cm). Additional metastases were detected by IUS in seven patients resulting in a change of operative procedure in 20.6%.

CONCLUSION

Staging accuracy of colorectal liver metastasis is influenced by neoadjuvant chemotherapy. For PET, decreased tumour metabolism rather than downsizing may account for a drop in sensitivity after neoadjuvant chemotherapy. IUS is critical to avoid incomplete resections.

Validation of sentinel lymph node dissection in prostate cancer: experience in more than 2,000 patients

PURPOSE

Sentinel lymph node dissection (SLND) has replaced extended lymphadenectomy for nodal staging in several solid tumours. We present our results of SLND in prostate cancer in regard to detection and false-negative rate.

METHODS

In a 2-day protocol about 300 MBq (99m)Tc-nanocolloid are injected into the prostate. Two hours later static scans of the pelvis are performed to get information about the number and location of radioactive lymph nodes. During surgery the radioactive nodes are excised with the help of a gamma probe and sent separately to the pathologist. The histological procedure includes haematoxylin and eosin staining, serial sections and immunohistochemistry.

RESULTS

Since 1999, a total of 2,020 men underwent SLND alone or in combination with either standard or extended lymphadenectomy after radical retropubic prostatectomy. Lymph nodes positive for metastases were found in 16.7% of patients. The scintigraphic detection rate was 97.6% and the intraoperative detection rate 98%. For 187 lymph node-positive men who had either standard or extended lymphadenectomy in addition to SLND the false-negative rate could be calculated, resulting in false-negative findings in 11 of 187 patients (6%).

CONCLUSION

Our results demonstrate that SLND in prostate cancer is a reliable procedure for nodal staging.

[Influence of the injection technique on the false negative rate of SLNE in multifocal breast cancer]

AIM

We investigated the influence of the injection technique on the false negative rate in identifying the sentinel lymph node in multifocal breast cancer.

PATIENTS, METHODS

958 consecutive patients were divided into unifocal and multifocal breast cancer patients. The scintigrafic and intraoperative detection rate as well as the false negatives were calculated in relation to peritumoral or subareolar injection.

RESULTS

In all patients the scintigrafic and intraoperative detection rate exceeded 99%, except in patients with multifocal cancer, who were injected peritumorally. In this group the intraoperative detection rate declined to 96%. In patients with unifocal breast cancer the false negative rate was below 5%, independent of the injection technique. Multifocal breast cancer patients showed a significant dependence on the injection technique. The false negative rate was 26.3% in patients with peritumoral injection and 5.6% in those with subareolar injection.

CONCLUSION

The results clearly demonstrate that in multifocal breast cancer a reliable detection of a SLN is impossible with the peritumoral injection technique. Subareolar injection seems to be a way to operate on multifocal breast cancer with SLNE, but the number of investigated patients is too low for statistic approval. So, prospective studies should be performed to validate these preliminary results before SLNE becomes routine in multifocal breast cancer.

Radioiodine therapy for combined disseminated and nodular thyroid autonomy

Ziel: Die kombinierte Schilddrüsenautonomie wird zurzeit mit unterschiedlichen Konzepten radioiodtherapiert. Der Unterschied liegt in der Berechnung des autonomen Volumens. In dieser retrospektiven Studie wird ein neues Verfahren der Volumenberechnung vorgestellt. Patienten und Methoden: Bei 398 Patienten mit kombinierter Autonomie, die eine gute Korrelation von heißen Knoten und sonographisch zirkumskripten Läsionen aufweisen, wird das Volumen der heißen Knoten anhand der sonographischen und szintigraphischen Messdaten ermittelt und das Volumen der disseminierten Autonomie mit einem Wichtungsfaktor (VF) bewertet. Dieser Faktor entspricht dem Quotienten der Impulsdichte von disseminiertem zu zircumskriptem Gewebe im Schilddrüsenszintigramm. Nach Messung des maximalen Iod-131-Uptakes und der effektiven Halbwertszeit (HWZ) in einem Radioiodtest wird die Aktivitätsmenge für eine Herddosis von 400 Gy ermittelt. Ergebnisse: Die Erfolgsquote beträgt mit und ohne Thyreostase 97% bei einer Hypothyreoserate von 18,6 % in der Bewertung des Therapieerfolges ab dem 4. Monat nach Radiojodtherapie. Schlussfolgerung: Die Radioiodtherapie bei kombinierter Autonomie unter Verwendung eines Wichtungsfaktors (Produkt aus VF und Volumen des perinodulären Gewebes) für die Berechnung der Therapieaktivität des disseminierten Autonomieanteils führt bei Patienten mit guter Korrelation von sonographischem und szintigraphischem Befund zu einer hervorragenden Erfolgsquote.

[Radioiodine therapy for combined disseminated and nodular thyroid autonomy. Results after using a correction term for the disseminated part]

AIM

In combined focal and disseminated thyroid autonomy a variety of concepts in the treatment with radioiodine are used. The difference lies mainly in the calculation of the autonomous volume. This retrospective study shows a new method of calculating the autonomous volume.

PATIENTS AND METHODS

In 398 patients with combined thyroid autonomy and good correlation of scintigraphically hot nodules and lesions defined by ultrasound the volume of the nodules is ascertained from scintigraphic and ultrasound parameters and the volume of the disseminated autonomous tissue is assessed with a weighting factor (VF). This factor is the ratio of impulse density in a ROI over the disseminated volume divided by the corresponding impulse density over the nodular volume of the thyroid scintigraphy. The sum of nodular volume and weighted perinodular volume gives the total autonomous volume. A standard radioiodine test gives the maximum iodine-131-uptake and effective half-life to calculate the activity to obtain a treatment dose of 400 Gy.

RESULTS

The rate of success with and without thyrostatic medication was 97% with an 18.6% rate of hypothyroidism observed from 4 months post therapy onwards.

CONCLUSION

The use of the weighting factor VF in the treatment of combined autonomy leads to an excellent rate of success in patients with good correlation of functional imaging and ultrasound findings.

Unilateral multicystic dysplastic kidney: experience in children

OBJECTIVES

To report a retrospective study of unilateral multicystic dysplastic kidneys (MCDK) in children, assessing the contralateral kidneys and urinary tract, the functional consequences, and the urological and nephrological management and outcome, as unilateral MCDK is the most common cause of renal cystic disease in children, and malformations of the contralateral urinary tract and kidney (pelvi-ureteric obstruction, megaureter, reflux, renal dysplasia) have been reported.

PATIENTS AND METHODS

The study included 97 patients (60 boys, 37 girls) with MCDK seen between 1985 and 1998; 82 were diagnosed in utero by ultrasonography (US). After birth, the diagnosis was verified by US, renal scanning (in 93) or intravenous urography (in four), and 89 (92%) had voiding cysto-urethrography (VCUG). Of the 97 children, 87 (90% had a mean (range) follow-up of 44.3 (15-115) months.

RESULTS

The MCDK was removed in 17 children; the follow-up of 75 children (five lost to follow-up) showed total involution of the MCDK in 25%, shrinkage in 60% and a stable size in 15%. None had any sign of malignancy. The contralateral kidney showed anomalies in 19 of 97 children (20%); 12 had a dilated renal pelvis (two with megaureter), six had a high echogenicity of the contralateral kidney (one had reflux, and two also pelvic dilatation). In only four of the 89 children was reflux found by VCUG; 16 of the 19 anomalies were detected by US. Five children needed surgery on the contralateral urinary tract (three a pyeloplasty, and one each a pyeloplasty plus ureteroneocystostomy, and an antireflux procedure). Of the contralateral kidneys 43% showed compensatory hypertrophy. There was mild renal insufficiency in three children; renal function seemed to be slightly impaired in many. Five infants had hypertension (four with spontaneous resolution) caused by renal scarring after pyelonephritis or inborn dysplasia of the contralateral kidney. There were symptomatic urinary tract infections in seven children.

CONCLUSION

US can be used safely to diagnose unilateral MCDKs and malformations of the contralateral urinary tract and kidney. In cases where US of the dysplastic kidney remains uncertain renal scintigraphy is necessary to detect the lack of renal function. The low rate of reflux makes routine VCUG unnecessary if the contralateral upper urinary tract and kidney appear to be normal on US. Nephrectomy of the dysplastic kidney in typical cases is also unnecessary. A long-term nephro-urological follow-up of children with MCDK is recommended.

[Valence of F-18-FDG-PET in the diagnosis of malignant lymphoma]

PET enables tomographic imaging and quantification of molecular metabolism with high temporal and spatial resolution. For routine clinical questions in oncology F-18-labeled fluorodeoxyglucose is the tracer of choice. In malignant lymphoma staging, response control and follow-up studies are valid indications. The initial glucose-uptake and especially the response of metabolism to therapy are in correlation with the outcome of the disease. Complementary to conventional staging PET is able to detect further lymphnode manifestation or extranodal involvement that can result in up-staging. Down-staging is less frequent. In follow-up studies PET is valuable, to assess therapy response, to differentiate viability of lymphoma from fibrous remnants at end of therapy and to detect relapse at an early stadium. In this context it proves to be superior to conventional tomographic imaging. In individual cases relevant therapeutic consequences arise from the metabolic PET-informations. Whether in future PET will be able to partially replace conventional imaging and whether it withstands to cost/effectiveness analysis requires additional prospective studies.

FDG-PET for detection of recurrences from malignant primary bone tumors: comparison with conventional imaging

BACKGROUND

The aim of this study was to assess the diagnostic ability of positron emission tomography using 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG-PET) in the detection of recurrences from malignant primary bone tumors compared with conventional imaging.

PATIENTS AND METHODS

In 27 patients (6 osteosarcomas, 21 Ewing's sarcomas), 41 FDG-PET examinations performed for diagnosis or exclusion of recurrent disease were evaluated. Conventional imaging techniques consisted of magnetic resonance imaging of the primary tumor site, thoracic computed tomography, and Tc-99m methylene diphosphonate bone scintigraphy. The reference methods were the histopathological analysis and/or the clinical and imaging follow-up.

RESULTS

In 25 examinations reference methods revealed 52 sites of recurrent disease (local n = 7; distant: osseous n = 22, pulmonary n = 13, soft tissue n = 10). On an examination-based analysis FDG-PET had a sensitivity of 0.96, a specificity of 0.81 and an accuracy of 0.90. Corresponding values for conventional imaging were 1.0, 0.56 and 0.82.

CONCLUSIONS

The sensitivity, specificity and accuracy of FDG-PET in the detection of recurrences from osseous sarcomas are high. On an examination-based analysis, FDG-PET had a not significantly lower sensitivity in comparison with conventional imaging. However, FDG-PET showed a small advantage in the detection of osseous and soft-tissue recurrences compared with conventional imaging.

High-activity samarium-153-EDTMP therapy followed by autologous peripheral blood stem cell support in unresectable osteosarcoma

PURPOSE

Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. These patients may benefit from therapy with radiolabeled phosphonates.

PATIENTS AND METHODS

Six patients (three male, three female; seven to 41 years) with unresectable primary osteosarcoma (n = 3) or unresectable recurrent sites of osteosarcomas (n = 3) were treated with high-activity of Sm-153-EDTMP (150 MBq/kg BW). In all patients autologous peripheral blood stem cells had been collected before Sm-153-EDTMP therapy.

RESULTS

No immediate adverse reactions were observed in the patients. In one patient bone pain increased during the first 48 hrs after therapy. Three patients received pain relief. Autologous peripheral blood stem cell reinfusion was performed on day +12 to +27 in all patients to overcome potentially irreversible damage to the hematopoietic stem cells. In three patient external radiotherapy of the primary tumor site was performed after Sm-153-EDTMP therapy and in two of them polychemotherapy was continued. Thirty-six months later one of these patients is still free of progression. Two further patients are still alive. However, they have developed new metastases. The three patients who had no accompanying external radiotherapy, all died of disease progression five to 20 months after therapy.

CONCLUSION

These preliminary results show that high-dose Sm-153-EDTMP therapy is feasible and warrants further evaluation of efficacy. The combination with external radiation and polychemotherapy seems to be most promising. Although osteosarcoma is believed to be relatively radioresistant, the total focal dose achieved may delay local progression or even achieve permanent local tumor control in patients with surgically inaccessible primary or relapsing tumors.

FDG-PET for detection of pulmonary metastases from malignant primary bone tumors: comparison with spiral CT

BACKGROUND

The purpose was the comparison of positron emission tomography using F-18-fluorodeoxy-glucose (FDG-PET) and spiral thoracic CT to detect pulmonary metastases from malignant primary osseous tumors.

PATIENTS AND METHODS

In 71 patients with histologically confirmed malignant primary bone tumors (32 osteosarcomas, 39 Ewing's sarcomas) 111 FDG-PET examinations were evaluated with regard to pulmonary/pleural metastases in comparison with spiral thoracic CT. Reference methods were the clinical follow-ups for 6-64 months (median 20 months) or a histopathologic analysis.

RESULTS

In 16 patients (23%) reference methods revealed a pulmonary/pleural metastatic disease. FDG-PET had a sensitivity of 0.50, a specificity of 0.98, and an accuracy of 0.87 on a patient based analysis. Comparable values for spiral CT were 0.75, 1.00, and 0.94. It was shown that no patient who had a true positive FDG-PET had a false negative CT scan, nor was a pulmonary metastases detected earlier by FDG-PET than by spiral CT.

CONCLUSIONS

There seems to be a superiority of spiral CT in the detection of pulmonary metastases from malignant primary bone tumors as compared with FDG-PET. Therefore, at present a negative FDG-PET cannot be recommended to exclude lung metastases. However, as specificity of FDG-PET is high, a positive FDG-PET result can be used to confirm abnormalities seen on thoracic CT scans as metastatic.

18F-Fluorodeoxyglucose PET in a patient with primary small bowel lymphoma: the only sensitive method of imaging

This report describes the case of a patient with primary small bowel lymphoma. Well-established methods of imaging did not give a hint on diagnosis. Increased 18F-fluorodeoxyglucose uptake was visualized on performance of positron emission tomography, corresponding with the intraoperatively found tumorous process. The present case points to a potential superiority of positron emission tomography in visualizing primary small bowel lymphoma.

Whole-body MR imaging for detection of bone metastases in children and young adults: comparison with skeletal scintigraphy and FDG PET

OBJECTIVE

The purpose of this study was to compare the diagnostic accuracy of whole-body MR imaging, skeletal scintigraphy, and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for the detection of bone metastases in children.

SUBJECTS AND METHODS

Thirty-nine children and young adults who were 2--19 years old and who had Ewing's sarcoma, osteosarcoma, lymphoma, rhabdomyosarcoma, melanoma, and Langerhans' cell histiocytosis underwent whole-body spin-echo MR imaging, skeletal scintigraphy, and FDG PET for the initial staging of bone marrow metastases. The number and location of bone and bone marrow lesions diagnosed with each imaging modality were correlated with biopsy and clinical follow-up as the standard of reference.

RESULTS

Twenty-one patients exhibited 51 bone metastases. Sensitivities for the detection of bone metastases were 90% for FDG PET, 82% for whole-body MR imaging, and 71% for skeletal scintigraphy; these data were significantly different (p < 0.05). False-negative lesions were different for the three imaging modalities, mainly depending on lesion location. Most false-positive lesions were diagnosed using FDG PET.

CONCLUSION

Whole-body MR imaging has a higher sensitivity than skeletal scintigraphy for the detection of bone marrow metastases but a lower sensitivity than FDG PET.

FDG-PET for detection of pulmonary metastases from malignant primary bone tumors: comparison with spiral CT

BACKGROUND

The purpose was the comparison of positron emission tomography using F-18-fluorodeoxy-glucose (FDG-PET) and spiral thoracic CT to detect pulmonary metastases from malignant primary osseous tumors.

PATIENTS AND METHODS

In 71 patients with histologically confirmed malignant primary bone tumors (32 osteosarcomas, 39 Ewing's sarcomas) 111 FDG-PET examinations were evaluated with regard to pulmonary/pleural metastases in comparison with spiral thoracic CT. Reference methods were the clinical follow-ups for 6-64 months (median 20 months) or a histopathologic analysis.

RESULTS

In 16 patients (23%) reference methods revealed a pulmonary/pleural metastatic disease. FDG-PET had a sensitivity of 0.50, a specificity of 0.98, and an accuracy of 0.87 on a patient based analysis. Comparable values for spiral CT were 0.75, 1.00, and 0.94. It was shown that no patient who had a true positive FDG-PET had a false negative CT scan, nor was a pulmonary metastases detected earlier by FDG-PET than by spiral CT.

CONCLUSIONS

There seems to be a superiority of spiral CT in the detection of pulmonary metastases from malignant primary bone tumors as compared with FDG-PET. Therefore, at present a negative FDG-PET cannot be recommended to exclude lung metastases. However, as specificity of FDG-PET is high, a positive FDG-PET result can be used to confirm abnormalities seen on thoracic CT scans as metastatic.

Characterization of 3-[123I]iodo-L-alpha-methyl tyrosine ([123I]IMT) transport into human Ewing's sarcoma cells in vitro

3-[(123)I]Iodo-L-alpha-methyl tyrosine ([(123)I]IMT) scintigraphy of extracranial malignant tumors has been described, but little is known about the transport systems involved in [(123)I]IMT uptake into extracranial tumor cells. Here, the precise kinetics of [(123)I]IMT transport into human Ewing's sarcoma cells (VH-64) was determined. The apparent Michaelis constant was of high affinity value (K(m)=41.7+/-3.9 microM) and maximum transport velocitiy amounted to V(max)=20.7+/-0.6 nmol x mg protein(-1) x 10 min(-1). Inhibition experiments revealed the predominance of [(123)I]IMT uptake via sodium-independent system L.

Evaluation of chemotherapy response in primary bone tumors with F-18 FDG positron emission tomography compared with histologically assessed tumor necrosis

PURPOSE

The purpose of this study was to evaluate the potential of positron emission tomography using F-18-fluoro-2-deoxy-D-glucose (FDG PET) to assess the chemotherapy response of primary osseous tumors compared with the degree of necrosis determined histologically.

PATIENTS AND METHODS

Seventeen patients with primary bone tumors (11 osteosarcomas, 6 Ewing's sarcomas) were examined using FDG PET and planar bone scintigraphy before neoadjuvant chemotherapy and before surgery. Tumor response was classified histologically according to Salzer-Kuntschik (grades I-II: good response; grades IV-VI: poor response). In both imaging methods, quantification was performed using tumor to nontumor ratios (T:NT).

RESULTS

Histologically, 15 patients were classified as having good responses (grade I, n = 1; grade II, n = 6; grade III, n = 8) and two as having poor responses (grades IV and V). FDG PET showed more than a 30% decrease in T:NT ratios in all patients who had good responses. However, three of these patients had increasing bone scintigraphy T:NT ratios, and another five had decreasing ratios of less than 30%. The patients with poor responses had increasing T:NT ratios and decreasing ratios of less than 30%, respectively, using both imaging methods.

CONCLUSIONS

FDG PET seems to be a promising tool for evaluating the response of primary osseous tumors to chemotherapy. In this preliminary study, FDG PET was superior to planar bone scintigraphy.

FDG-PET for detection of osseous metastases from malignant primary bone tumours: comparison with bone scintigraphy

The purpose of this study was to compare positron emission tomography using fluorine-18 fluorodeoxyglucose (FDG-PET) and technetium-99m methylene diphosphonate (MDP) bone scintigraphy in the detection of osseous metastases from malignant primary osseous tumours. In 70 patients with histologically proven malignant primary bone tumours (32 osteosarcomas, 38 Ewing's sarcomas), 118 FDG-PET examinations were evaluated. FDG-PET scans were analysed with regard to osseous metastases in comparison with bone scintigraphy. The reference methods for both imaging modalities were histopathological analysis, morphological imaging [additional conventional radiography, computed tomography (CT) or magnetic resonance imaging (MRI)] and/or clinical follow-up over 6-64 months (median 20 months). In 21 examinations (18%) reference methods revealed 54 osseous metastases (49 from Ewing's sarcomas, five from osteosarcomas). FDG-PET had a sensitivity of 0.90, a specificity of 0.96 and an accuracy of 0.95 on an examination-based analysis. Comparable values for bone scintigraphy were 0.71, 0.92 and 0.88. On a lesion-based analysis the sensitivity of FDG-PET and bone scintigraphy was 0.80 and 0.72, respectively. Analysing only Ewing's sarcoma patients, the sensitivity, specificity and accuracy of FDG-PET and bone scan were 1.00, 0.96 and 0.97 and 0.68, 0.87 and 0.82, respectively (examination-based analysis). None of the five osseous metastases from osteosarcoma were detected by FDG-PET, but all of them were true-positive using bone scintigraphy. In conclusion, the sensitivity, specificity and accuracy of FDG-PET in the detection of osseous metastases from Ewing's sarcomas are superior to those of bone scintigraphy. However, in the detection of osseous metastases from osteosarcoma, FDG-PET seems to be less sensitive than bone scintigraphy.

High-activity samarium-153-EDTMP therapy in unresectable osteosarcoma

Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. We applied high-activity Sm-153-EDTMP therapy within a multimodal therapy concept to improve local control of an unresectable osteosarcoma with poor response to initial polychemotherapy. A 21-year-old woman with an extended, unresectable pelvic osteosarcoma and multiple pulmonary metastases was treated with high-activity of Sm-153- EDTMP (150 MBq/kg BW, total 8.1 GBq). Afterwards external radiotherapy of the primary tumor site was performed and polychemotherapy was continued, followed by autologous peripheral blood stem cell reinfusion. Within 48 h after Sm-153-EDTMP application the patient had complete pain relief. After three weeks the response was documented by 3-phase Tc-99m-MDP bone scintigraphy (primary tumor and metastases: decreased tracer uptake), whole-body F-18-FDG-PET (primary tumor and metastases: diminution of glucose metabolism) and thoracic CT (metastases: reduction of size). The present case warrants further evaluation of feasibility and efficacy of this multimodal therapy combination of high-activity Sm-153-EDTMP therapy, external radiation, polychemotherapy and stem cell support for unresectable osteosarcomas.

Reconstructive treatment of sclerosing osteomyelitis of the entire femur of 30 years' duration with avoidance of segmental resection

We describe the successful operative treatment of a patient with chronic sclerosing osteomyelitis of the femur in which en bloc resection was avoided. Therapy consisted of combined endoscopic, computed tomography and bone scan-guided fenestration and intramedullary reaming, with removal of all sclerotic zones and normalization of the cortical thickness. An adequate supply of oxygen to the area was ensured by improved vascularisation and the application of hydrogen peroxide. At the medium term follow-up no recurrence was seen, and hip and knee function was normal.

Determination of extent and activity with radionuclide imaging in Erdheim-Chester disease

Erdheim-Chester disease usually involves the diaphyseal and metaphyseal regions of tubular bones and various visceral organs. A 56-year-old woman presented with the histologically confirmed diagnosis of Erdheim-Chester disease. A Tc-99m MDP bone scan revealed the entire extent of the skeletal disease and showed unusual involvement of the epiphyses and axial skeleton. In addition to MRI, a Ga-67 citrate scan including SPECT showed extensive soft-tissue infiltration of different organs. Both Tc-99m MDP and Ga-67 scintigraphy are useful tools in determining the distribution of this rare disease.

[Role of 18F-FDG positron emission tomography in surgical evaluation]

Positron emission tomography (PET) using F-18-fluorine-deoxy-glucose (FDG) as a metabolic marker is a non-invasive diagnostic tool that can distinguish malignant processes from normal tissue by means of increased glycolysis. Since the advent of whole-body scanning, its higher spatial resolution compared with conventional scintigraphic methods leads to widespread applications of FDG-PET in oncology. The clinical value of FDG-PET has been proven for a number of tumor entities. As will be shown in the following review for bronchial, colorectal and pancreatic malignomas, functional imaging with FDG-PET provides relevant diagnostic information complementary to morphologic imaging.

High-Activity Samarium-153-EDTMP Therapy in Unresectable Osteosarcoma

Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. We applied high-activity Sm-153-EDTMP therapy within a multimodal therapy concept to improve local control of an unresectable osteosarcoma with poor response to initial polychemotherapy. A 21-yearold woman with an extended, unresectable pelvic osteosarcoma and multiple pulmonary metastases was treated with high-activity of Sm-153- EDTMP (150 MBq/kg BW, total 8.1 GBq). Afterwards external radiotherapy of the primary tumor site was performed and polychemotherapy was continued, followed by autologous peripheral blood stem cell reinfusion. Within 48 h after Sm-153-EDTMP application the patient had complete pain relief. After three weeks the response was documented by 3-phase Tc-99m-MDP bone scintigraphy (primary tumor and metastases: decreased tracer uptake), whole-body F-18-FDG-PET (primary tumor and metastases: diminution of glucose metabolism) and thoracic CT (metastases: reduction of size). The present case warrants further evaluation of feasibility and efficacy of this multimodal therapy combination of high-activity Sm-153-EDTMP therapy, external radiation, polychemotherapy and stem cell support for unresectable osteosarcomas.

Simultaneous evaluation of fatty acid metabolism and myocardial flow in an explanted heart

The biodistribution of the fatty acid analog [131I]PHIPA 3-10, was compared to the flow tracer 99mTc-sestamibi by quantitative analysis in a dual-isotope study performed during a heart transplantation.

METHODS

Iodine-131-PHIPA 3-10 and 99mTc-sestamibi were injected simultaneously approximately 20 min prior to the start of surgical procedure. Scintigraphic images of the sliced explanted heart were compared to the preoperative in vivo scans using [123I]PHIPA 3-10, 201TI and 99mTc-sestamibi. In 14 tissue samples of the explanted heart, the radioactive contents from [131I]PHIPA 3-10 and 99mTc-sestamibi were calculated as %ID/g-values and correlated with the corresponding histology.

RESULTS

In the preoperative scans, a mismatch of fatty acid uptake and perfusion ([123I]PHIPA 3-10 > flow) was observed which indicated residual viable myocardium, while a matched defect was associated with scar. In viable myocardium, there was a significantly higher accumulation of [131I]PHIPA 3-10 compared to 99mTc-sestamibi (mean 5.9 x 10(-3) versus 2.7 x 10(-3)%ID/g),whereas in scars the uptake of both tracers was comparable (1.2 x 10(-3) versus 1.4 x 10(-3)%ID/g).

CONCLUSION

Myocardial viability can be defined more accurately with radioiodinated PHIPA 3-10 than with 99mTc-sestamibi. The differences of biodistribution in viable myocardium and scars indicate that not only perfusion but also the metabolic state of the myocardium can be evaluated with radioiodinated PHIPA 3-10.

Structure distribution relationship of iodine-123-iodobenzamides as tracers for the detection of melanotic melanoma

The influence of systematic structure variations on the biodistribution of positional isomers of N-(N'-dialkylaminoethylene)-[123I]iodobenzamide (ABA) derivatives in melanoma-bearing animals was investigated.

METHODS

Radioiodination of six bromo benzamide precursors was achieved by Cu(1)-assisted nonisotopic halogen exchange. Organ distribution, scintigraphic and metabolic studies were performed in nude mice bearing a human melanotic MM (SK-MEL 25). A patient suffering from melanotic melanoma underwent scintigraphy with a [123I]iodobenzamide.

RESULTS

High radiochemical yields of 80%-95% and specific activities of > 5 TBq/ mumole were obtained. Animal studies revealed specific tumor uptake of all compounds with longest retention of the most lipophilic derivative p-[123I]ABA 2-2. At shorter times, however, o-[123I]ABA 2-2 exhibited the highest tumor uptake (8.9% ID/g, 1 hr p.i., 10.9% ID/g, 4 hr p.i.). Metabolization of o-[123I]ABA 2-2, mainly to o-[123I]iodohippuric acid (OIH), followed by fast renal excretion of the metabolites lead to tumor/nontumor ratios (T/NT) of > 400 for tumor/blood, and > 70 for tumor/liver at 48 h p.i. Unknown metastases could be localized in a patient using o-[123I]ABA 2-2.

CONCLUSION

The effects of the structure variation of iodobenzamides on their lipophilicity, metabolism and thus pharmacokinetics lead to the suggestion of o-[123I]ABA 2-2 as a favorable melanoma imaging agent.

Use of various diagnostic methods in a patient with Gaucher disease type I

A series of plain radiographs, bone scans, bone marrow scans, and MRIs is reported in a patient with Gaucher disease type I, in whom two episodes of acute bone crisis developed during a 6-year period of follow-up. Acute bone crisis and global indolent bone marrow displacement could both be assessed by bone marrow scintigraphy, whereas MRI could better clarify the corti-comedullary alteration after bone infarction. Thus, MRI and bone marrow scintigraphy could be used as complementary imaging methods in the management of patients with Gaucher disease.

[Positron emission tomography for primary tumor detection in lymph node metastases with unknown primary tumor]

In a prospective study 16 patients with cervical lymph node metastases from an occult tumor were analyzed by (18F)FDG positron emission tomography (PET). The aim of this study was to locate the primary tumor. In 7 patients a localized increase in activity was seen on PET, with this site of activity histologically proven in 4 patients. No biopsies were taken in 3 patients in areas with a high risk of complications. In a follow-up procedure at 2-22 months after primary radiation therapy in the other 9 patients, no primary tumor has been identified to date.

Synthesis, characterization and biodistribution of neutral and lipid-soluble 99mTc-bisaminoethanethiol spiperone derivatives: possible ligands for receptor imaging with SPECT

Using parts of the molecular structure of spiperone, two new ligand systems for complexation with [99mTc]technetium were prepared in order to develop potential receptor imaging agents for single photon emission computer tomography (SPECT). The bis-aminoethanethiols (BAT): 1-benzyl-4-(2-mercapto-2-methyl-4-aza-pentyl)-4-(2-mercapto-2-methyl- propylamino)-piperidine (benzylpiperidyl-BAT, BP-BAT) and 1-[3-(4-fluorobenzoyl)-propyl]-4-(2-mercapto-2-methyl-4-aza-pentyl)-4- (2-mercapto-2-methyl-propyl-amino)-piperidine (butyrophenoylpiperidyl-BAT, BUP-BAT) form stable, neutral and lipid soluble complexes with [99mTc]technetium at pH > or = 11 using SnCl2 as reducing agent in nearly quantitative radiochemical yields. Biodistribution of 99mTc-BP-BAT and 99mTc-BUP-BAT in rats showed a moderate clearance from blood and low uptake and retention in the liver, whereas brain uptake was moderate, however with prolonged brain retention. On the other hand, significant accumulations and retentions were observed in heart, kidney and lung with increasing oxygen/blood ratios up to 24 h. Within 24 h p.i. 22 and 29% of the injected dose (i.d.) of 99mTc-BP-BAT and 99mTc-BUP-BAT were eliminated by hepatobiliary excretion whereas 22% i.d. of both 99mTc-BAT complexes were excreted into the urine. Although first biodistribution studies of 99mTc-BP-BAT and 99mTc-BUP-BAT in rats showed relatively low brain uptake, the high uptake in peripheral, receptor rich organs indicates that compounds of this type may be used as a basis for further structural modification to develop agents with optimal properties for cerebral or peripheral receptor imaging with SPECT.

[The diabetic foot]

Foot disease in patients with diabetes mellitus is multifactorial and results from a combination of peripheral neuropathy, vascular compromise and superimposed infection. Foot complications in diabetic patients are common and account for more hospital days than any other aspects of their disease. Therefore, familiarity with the spectrum of findings in the different imaging modalities appears essential. Radiographically, significant changes include Charcot joints of the tarsus (destructive type) and bone absorption of the forefoot (mutilating type). In diabetic foot problems, magnetic resonance imaging and leukocyte scintigraphy appear to be the most effective tools for detection of osteomyelitis, and a negative study makes osteomyelitis unlikely. However, the findings of both techniques in active, noninfected neuropathic osteoarthropathy may be indistinguishable from those of osteomyelitis.

[67Ga scintigraphy in acute sarcoidosis with Heerfordt's syndrome]

Sarcoidosis is a chronic multisystem disorder of unknown etiology characterized by non-caseating epitheloid granulomas. We report a case of a 29-year old female with acute sarcoidosis and Heerfordt's syndrome (parotid enlargement, anterior uveitis and facial nerve palsy) who had a typical clinical constellation but no histologic criteria of a granulomatous inflammatory process in transbronchial lung biopsy. 67Ga scintigraphy revealed such a typical pattern of accumulation that sarcoidosis could be diagnosed despite negative histological findings.

67Ga-Szintigraphie bei akuter Sarkoidose mit Heerfordt-Syndrom

Die Sarkoidose ist eine chronische Systemerkrankung unbekannter Ätiologie, die durch nichtverkäsende epitheloidzellige Granulome gekennzeichnet ist. Wir berichten über eine 29jährige Patientin mit akuter Sarkoidose und Heerfordt-Syndrom (Parotisschwellung, Iridozyklitis und Fazialisparese), bei der zwar eine typische klinische Befundkonstellation vorlag, die transbronchiale Lungenbiopsie jedoch histologisch keinen granulomatösen Entzündungsprozeß nachweisen konnte. Die 67Ga-Szintigraphie zeigte ein so typisches Anreicherungsmuster, daß trotz negativer Histologie die Diagnose gestellt werden konnte.

[Spinal metastases. Value of diagnostic procedures in the initial diagnosis and follow-up]

In this retrospective study plain radiographs, radionuclide bone scans, computed tomography (CT) and magnetic resonance (MRT) examinations of 115 patients with metastatic carcinoma of the spine were analyzed. In 32 patients metastases were proven histologically and in the remainder by follow-up studies. Altogether, 513 vertebrae were evaluated. Forty-one patients had histologically proven breast cancer, 14 renal cell carcinoma, 11 prostate cancer, 8 melanoma. 8 tumors of the gastrointestinal system and 7 bronchial carcinoma. Evaluation of the plain films showed that the initial site of metastasis (n = 463) was the vertebral body in 441 cases and the pedicles in 294 cases. In CT scans most of the lesions confined to one part of the vertebral body (36 of 98) were localized in the posterior part. Twelve percent of the metastases were diagnosed with conventional radiography and 17% of those diagnosed with CT were not detected in skeletal scintigraphy. MRI was rarely used in diagnosing occult vertebral metastases (n = 37); 22% of the metastases demonstrated by MRI were not detected in skeletal scintigraphy. We concluded that only in 63.8% was the pedicle sign the initial site of metastasis on plain films. Bone scans and plain films are the most important diagnostic procedures for detecting and monitoring vertebral metastases. CT and MRI are only needed in patients with neurological symptoms and persistent pain.

Scintigraphic detection of osteomyelitis in osteopetrosis

METHODS AND RESULTS

The diagnosis of osteomyelitis in severe osteopetrosis may be difficult since altered bone architecture and fractures veil the typical radiographic signs of inflammation. We present a case of adult osteopetrosis with questionable clinical and radiographic signs of two osteomyelitic foci in the foot.

CONCLUSION

Despite severe skeletal disease, the combination of skeletal and leukocyte scintigraphy suggested the diagnosis of infection.