Biomedical subjects

H Bender

Publications and source records attributed to H Bender.

At least 37 records · Page 2Linked to original sources

PubMed1999

Possible role of FDG-PET in the early prediction of therapy outcome in liver metastases of colorectal cancer.

Nonresectable colorectal cancer metastases in the liver respond to chemotherapy in 20-25% only. Early identification of nonresponders might allow the use of other regimens. In a limited feasibility study, it should be determined whether (a) a single high-dose chemotherapy application has an early effect on glucose-utilization, detectable and quantitatable by noninvasive positron emission tomography using [18F]-Fluoro-deoxyglucose (FDG-PET) and (b) assess its value as a predictor of the final therapeutic outcome. A total of 10 patients with documented nonresectable liver metastases of a colorectal cancer were studied by FDG-PET, prior and 72 h after a single infusion of 5-Fluorouracil and Folinic acid (5-FU/FA). Glucose utilization was quantitated by determination of standard-uptake values and correlated with final therapy outcome following completion of the anticipated therapy cycle. Patients were followed up for at least 6 months. All metastases responding to therapy (n = 6) exerted a statistically significant decrease of FDG uptake (-22+/-10%), metastases (n = 2) showing a short-term effect (duration of tumor reduction <3 months) had a slightly diminished, and progressing metastases (n = 3) an enhanced FDG uptake (13+/-17%). Our preliminary data indicate that acute changes of glucose utilization-as detected by FDG-PET-following a single application of chemotherapy, seems to be indicative for the final therapeutic outcome, at least in liver metastases of colorectal cancer.

Adenocarcinoma↗

PubMed1999

Recombinant human thyrotropin in thyroid cancer and hypopituitarism due to sella metastasis.

We present a patient with thyroid cancer and hypopituitarism who required recombinant human thyrotropin (rhTSH) for 131I scanning with respect to subsequent therapy. The thyroid cancer had been unknown until central neurological symptoms developed, leading to the diagnosis of a huge metastasis to the sella that was the only manifestation of metastatic spread. The failure to generate endogenous thyrotropin (TSH) was overcome by the use of rhTSH for performing a 131I test. Unfortunately, the 131I uptake was not sufficient for therapy. This subject is the first reported case who required the application of rhTSH due to a single thyroid cancer metastasis in the sella region with secondary failure to generate endogenous TSH.

Aged↗

PubMed1999

Pain palliation with rhenium-186 HEDP in breast cancer patients with disseminated bone metastases.

PURPOSE: For patients with metastatic prostate cancer, first results have shown that rhenium-186 (Re-186) hydroxyethylidene diphosphonate (HEDP) is efficient in pain palliation of disseminated bone metastases. The aim of this study was to determine whether significant pain reduction can also be achieved in breast cancer patients with Re-186 HEDP. METHODS: Thirty patients with breast cancer who had multifocal painful bone metastases received a total of 38 intravenous Re-186 HEDP injections. Pain relief was assessed through daily documentation of the visual analog scale and analgesic consumption. A significant response to treatment was determined if the visual analog scale or analgesic consumption decreased significantly for at least 2 weeks. Blood counts were controlled at baseline and at weeks 4 and 8. RESULTS: A response to pain therapy was observed in 60% (18 of 30) of the patients. A reversible thrombocytopenia and leukopenia of grade 2 (according to World Health Organization criteria) was found in 4 and 2 patients, respectively. CONCLUSION: Patients with disseminated osseous metastases resulting from breast cancer can benefit from therapy with Re-186 HEDP.

Adult↗

PubMed1999

[Monoclonal anti-idiotype antibodies in immunotherapy of ovarian carcinoma (MAb ACA125) and breast carcinoma (MAb ACA14C5)].

Anti-idiotypic antibodies, which imitate a tumor-associated antigen by their variable region, offer an elegant method for the induction of a specific immune response, when used as a surrogate antigen for immunization. We generated anti-idiotypic antibodies imitating 2 different tumor-associated antigens. I. CA125 for ovarian carcinomas and II. 14C5, a tumor-associated cell substrate adhesion molecule on breast cancer cells, whereas the first approach could be introduced in a first clinical trial and the second was evaluated in an immunocompetent animal model. For the induction of an immune response against CA125, 18 patients with advanced ovarian cancer (n = 6) or heavily pretreated recurrences (n = 12) were immunized with the anti-idiotypic antibody MAb ACA125. Patients were treated with 2 mg anti-idiotype antibody every two weeks for 4 injections i.m. and then monthly. 12 of 18 patients demonstrated an anti-anti-idiotypic (Ab3) response, which was to a lower extent also directed against CA125 and 9 of 18 patients developed a CA125 specific cellular immune response by their peripheral blood lymphocytes. Based on this data a follow-up clinical trial in advanced ovarian cancer patients with minimal residual disease in an adjuvant approach after primary therapy was started to evaluate the effect of the immune response on the progression free survival. For immunotherapy of breast cancer, we generated a murine monoclonal anti-idiotypic antibody (MAb ACA14C5), which imitates a cell substrate adhesion molecule on breast cancer cells. The anti-idiotype was introduced in an immunocompetent animal to prove his capability on induction of an immune and tumor response. The results showed a highly significant difference in the tumor growth of the ACA14C5 treated group in contrast to the controls starting the immunization on day 6 after tumor cell application with 10 of 12 animals being cured from their tumor burden. Prophylactic immunization against the invasion antigen of breast cancer by anti-idiotypic antibodies showed protection against increasing tumor burden. However, in the situation of established tumors only minor responses could be detected. Vaccination with anti-idiotypic antibodies comprises an effective method for induction of a specific immune response against non-immunogenic tumor-associated antigens and should be therefore considered in immunological approaches to tumor therapy, where the primary structure and sequence of the antigen, e.g. CA125, is up to now not available.

Antibodies, Monoclonal↗

PubMed1999

Myocardial uptake of technetium-99m-furifosmin (Q12) versus technetium-99m-sestamibi (MIBI).

AIM: This study was performed to compare the myocardial uptake of Tc-99m-furifosmin (Q12) versus Tc-99m-sestamibi (MIBI) in correlation to the whole-body uptake under resting conditions. METHODS: 21 patients with coronary artery disease and no rest ischemia were examined. A whole-body scan was performed 60 min. p.i. under resting conditions. A quantification of the uptake (whole-body, heart and right lung) was done by ROI technique. RESULTS: The heart-to-lung ratio of Q12 (1.56 +/- 0.191) was significantly lower as compared to MIBI (1.94 +/- 0.197; p < 0.01). In contrast, the heart-to-whole-body ratios (Q12 versus MIBI: 0.027 +/- 0.012 versus 0.026 +/- 0.004; p < 0.76) did not differ. The lung-to-whole-body ratio (Q12 versus MIBI: 0.018 +/- 0.009 versus 0.013 +/- 0.002; p < 0.17) were different, but did not reach significance. CONCLUSION: These data show that under resting conditions the total myocardial uptake of Q12 does not differ significantly from that of MIBI. However, the pulmonary uptake of Q12 is slightly higher, resulting in a significant lower heart-to-lung ratio. These findings imply a lower image quality of Q12 compared to MIBI.

Adult↗

PubMed1999

[Evaluation of 99mTc(V)-DMSA imaging in patients with pharyngolaryngeal carcinoma].

OBJECTIVE: To evaluate the value of tumor-seeking agent 99mTc(V)-DMSA in patients with pharyngolaryngeal carcinoma and its biodistribution in human being. METHOD: Planar and SPECT scintigraphy with 99mTc(V)-DMSA were performed in 12 patients with histologically confirmed pharyngolaryngeal carcinoma. The dynamic distribution in patients was also analyzed. RESULT: 9 cases (11 lesions) showed increased uptake by planar imaging and 11 cases (19 lesions) were clearly demonstrated by SPECT images. Furthermore, distant metastatic lesions were showed in 5 patients. Biodistribution in patients showed the accumulation of 99mTc(V)-DMSA in kidney was significantly greater than other organs. CONCLUSION: These results could suggested the clinical utility of 99mTc(V)-DMSA, specially with SPECT, for detecting primary pharyngolaryngealcarcinoma and their metastatic lesions (both local and distant). 99mTc(V)-DMSA Tumor-seeking agent Pharyngolaryngeal carcinoma.

Aged↗

PubMed1998

Localization of colorectal carcinoma by rhenium-188-labeled B72.3 antibody in xenografted mice.

In order to evaluate the feasibility of 188Re-labeled antibodies for radioimmunotargeting, monoclonal antibody B72.3, recognizing TAG-72, expressed on the surface membranes of colorectal cancer cells, was directly labeled with 188Re, obtained from a 188W/188Re generator, using stannous tartrate and compared with 125I-labeled B72.3. As a control, a human IgG was also radiolabeled with 188Re and 125I. Prepared antibodies for 188Re labeling could be stored as kits. Biodistribution was determined in nude mice inoculated with human colorectal carcinoma LoVo. Labeling efficiency and immunoreactivity of 188Re-B72.3 were 80.3% and 64.7%, respectively. 188Re-B72.3 localized specifically in the LoVo tumors. Although the absolute tumor accumulation level of 188Re-B72.3 was lower than 125I-B72.3, 188Re-B72.3 demonstrated higher tumor-to-blood contrast than the 125I-labeled counterpart, 2.04 +/- 0.44 vs. 1.05 +/- 0.28 at 96 hours, because of fast clearance from the blood. 188Re-B72.3 seemed efficient for the imaging and therapy of colorectal carcinoma.

Animals↗

PubMed1998

188Re- and 99mTc-MAG3 as prosthetic groups for labeling amines and peptides: approaches with pre- and postconjugate labeling.

Either radiolabeled Tc-99m- or Re-188-labeled MAG3-4-nitrophenylester or unlabeled Bz-MAG3-4-nitrophenylester was reacted with amines and peptides to follow a pre- or a postconjugate radiolabeling route, respectively. The model compounds were N'-t-butyloxycarbonyl-1,6-diaminohexane (DH-Boc) and a Lys-protected derivative of the somatostatin analog RC-160 (cyclic D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH2). In the case of labeling DH-Boc, both the preconjugate labeling and the postconjugate labeling were found by using analytical HPLC to provide identical radiolabeled compounds regardless whether Re-188 or Tc-99m was used. The results are supported by infrared and mass-spectral data obtained from compounds synthesized using stable rhenium. The 188Re- or 99mTc-MAG3-RC-160 somatostatin analog were synthesized following the preconjugate labeling route and subsequent removal of the protecting group. Biodistributions of 188Re-and 99mTc-MAG3-RC-160 were evaluated in normal and tumor-bearing mice, and were similar to those of radioiodinated 131-RC-160. All radiolabeled analogs of RC-160 were rapidly cleared from the blood and were excreted through the hepatobiliary system with very little normal organ uptake. The tumor uptake (PC-3, human prostate adenocarcinoma) of systemically administered Re-188-MAG3-RC160 was very low, and it reached only 0.28% injected dose/g (%IDg) at 24 h postinjection, similar to what was obtained with I-131-RC-160. Intratumor injections resulted in significant tumor retentions (9.3% ID/g at 24 h).

Amines↗

PubMed1998

[Toxicity and radiation dosage of 2-(18F)-2-desoxy-D-glucose in positron emission tomography].

2-[18F]-FDG, a non-physiological glucose analogue, is the most important positron-emission- tomography (PET) radiopharmaceutical. As an example we refer to the production of 2-[18F]-FDG at the research center in Karlsruhe. 2-[18F]-FDG is synthesized in a "no carrier added" process. It is delivered at a maximal filling volume of 10 ml from a 14.5 ml batch with a batch-to-batch yield fluctuation from 5075 to 50,750 MBq and a specific activity from 1 to 10 GBq/mumol. The residual remaining synthesis reagents like solvents or catalysts have no toxicological relevance. The applicated dose per patient is in a range from 185 to 370 MBq and 1000 times lower than the correlating concentrations of stable FDG which can be regarded harmless in animals. 2-[18F]-FDG does not interfere with normal glucose metabolism. It is taken up by cells and phosphorylated to 2-[18F]-FDG-6-phosphate. The following dephosphorylation step is slow and the labeled compound is retained over several hours within the cells. Non-metabolized 2-[18F]-FDG is excreted rapidly in the urine to an extent of about 16% after 60 min, and 50% after 135 min, respectively. Fluorine-18F decays by emission of 511 KeV gamma photons. The whole body effective dose is reported to be 21 to 27 microSv/MBq. In case of an intravenous injection of 370 MBq this leads to a total dose of 7.8 to 10 mSv. The critical organ is the bladder wall (radiation dose 120 to 170 microSv/MBq or 80 to 100 mrem/mCi). The risk of a radiation induced late malignoma at 10 mSv can be estimated to be 1:2000. The genetical risk as a consequence of FDG-PET diagnostics would be 1:100,000 to 2:100,000 for dominant, and 5 times higher for recessive mutations.

Blood Glucose↗

PubMed1998

Redifferentiation therapy with retinoic acid in follicular thyroid cancer.

We report on a patient with a follicular Hurthle cell carcinoma in whom distant metastases were initially radioiodine negative or only weakly positive. Redifferentiation therapy with 13-cis retinoic acid induced a significant radioiodine uptake in metastatic tissue. Thyroglobulin (Tg) immunostaining and autoradiography of a bone metastasis in the right femur, which was initially radioiodine negative, proved Tg synthesis, combined with iodine incorporation into tumor cells. Glucose metabolism in metastases was partially increased and partially unchanged after redifferentiation therapy. The distinct increase of serum Tg after retinoic acid treatment was interpreted as a functional sign of redifferentiation.

Adenocarcinoma↗

PubMed1998

Redifferentiation therapy-induced radioiodine uptake in thyroid cancer.

UNLABELLED: Due to a dedifferentiation of tumor cells, some thyroid carcinomas lose their capability for radioiodine (RI) concentration. This phenomenon is associated with a worse prognosis and prevents effective treatment. Retinoic acid (RA) is known to induce redifferentiation in various kinds of tumors and has been used recently in thyroid cancer. METHODS: Twelve patients (9 women, 3 men) with 6 papillary, 4 follicular and 2 mixed-cell type tumors (including 4 Hurthle cell carcinomas) were treated orally with RA (dose: 1.18 +/- 0.37 mg/kg body weight) for at least 2 mo before RI therapy. None of the patients could be treated with any other modality (RI, surgery, external radiation) when RA administration was started. Initially, clinically important tumor sites did not take up significant amounts of RI. Changes of RI uptake and thyroglobulin (Tg) serum values were determined. Glucose metabolism was followed with fluorodeoxyglucose (FDG) PET imaging in 10 patients before and in 5 patients after RA treatment. RESULTS: In 2 patients, a significant RI uptake was induced by RA, and in another 3 patients a faint RI uptake was achieved (responder group). In 7 patients, no change of RI uptake was observed (nonresponder group). Median Tg was increased from 105-840 microg/liter during RA therapy in the responder group, which was significantly higher than the nonresponder group (173-134 microg/liter). FDG PET was positive in all 10 patients before RA therapy. PET showed variable patterns of changes (increase/decrease/disappearance) in glucose consumption related to RA response. CONCLUSION: RA can induce RI uptake in some patients with RI negative thyroid carcinoma tumor sites. Response to RA is associated with a significantly higher increase of Tg, suggesting that a restoration of Tg synthesis can be addressed as a redifferentiation parameter in these patients.

Adenocarcinoma, Follicular↗

PubMed1997

Comparison of fluorine-18 fluorodeoxyglucose positron emission tomography and technetium-99m methoxyisobutylisonitrile scintimammography in the detection of breast tumours.

The aim of this study was to compare, in breast cancer patients, the diagnostic accuracy of positron emission tomography (PET) using fluorine-18 fluorodeoxyglucose (FDG) and scintimammography (SMM) using technetium-99m methoxyisobutylisonitrile (MIBI). A total of 20 patients (40 breasts with 22 lesions) were evaluated serially with MIBI and, on the following day, with FDG. For SMM, planar and single-photon emission tomography imaging in the prone position was performed starting at 10 min following the injection of MIBI (740 MBq). For PET, scans were acquired 45-60 min after the injection of FDG (370 MBq) and attentuation correction was performed following transmission scans. Results from SMM and PET were subsequently compared with the histopathology results. True-positive results were obtained in 12/13 primary breast cancers (mean diameter=29 mm, range 8-53 mm) with both FDG and MIBI. False-negative results were obtained in two local recurrences (diameter <9 mm) with both FDG and MIBI. In benign disease, FDG and MIBI did not localize three fibrocystic lesions, two fibroadenomas and one inflammatory lesion (true-negative), but both localized one fibroadenoma (false-positive). Collectively, the results demonstrate a sensitivity of 92%, and a specificity of 86%, for primary breast cancer regardless of whether FDG or MIBI was used. In contrast to MIBI scintigraphy, FDG PET scored the axillae correctly as either positive (metastatic disease) or negative (no axillary disease) in all 12 patients. The tumour/non-tumour ratio for MIBI was 1.97 (range 1.43-3.1). The mean standard uptake value (SUV) for FDG uptake was 2.57 (range 0.3-6.2). The diagnostic accuracy of SMM was equivalent to that of FDG PET for the detection of primary breast cancer. For the detection of in situ lymph node metastases of the axilla, FDG seems to be more sensitive than 99mTc-MIBI.

Axilla↗

PubMed1997

Fluorodeoxyglucose whole-body positron emission tomography in colorectal cancer patients studied in routine daily practice.

PURPOSE: To evaluate the routine clinical value of attenuation-corrected whole-body fluorodeoxyglucose positron emission tomography in colorectal cancer, a total of 59 patients who were referred for evaluation of suspected or proven colorectal cancers were studied. METHODS: Positron emission tomography scans were recorded using a Siemens ECAT Exact 921/47. RESULTS: Median follow-up after the positron emission tomography study was 11 (mean, 12.3; range, 1-21) months. According to computed tomography, coloscopy, and ultrasound, we recorded eight apparently false-positive results. During later follow-up, however, three of those cases, which were negative with computed tomography, magnetic resonance imaging, sonography, or laparoscopy, turned out to be true-positive instead. In 3 patients, a primary colorectal cancer was suspected; in 26 patients, a recurrence of colorectal cancer was suspected. Eight patients were studied for follow-up after the history of colorectal cancer with no suspicion of recurrence. In 12 patients, the rise of serum tumor marker concentrations was the reason for the positron emission tomography study; 12 patients with known metastatic disease were also included ("restaging"). With regard to the entire patient population, we found an overall sensitivity of 100 percent, a specificity of 67 percent, and positive and negative predictive values of 92 and 100 percent, respectively. Being merely confirmative with respect to tumor recurrence or distant metastases in the majority of patients, positron emission tomography revealed a primary tumor in one patient and confirmed metastatic foci in several patients that had not been delineated by other imaging modalities. CONCLUSION: A whole-body positron emission tomography scan provides optimum conditions to locate metastatic lesions that might not be seen otherwise. There is a trend showing that positron emission tomography diagnostics as a consequence of early increased tumor markers is a highly sensitive combination, because computed tomography and magnetic resonance imaging were not as sensitive in early recurrences. Positron emission tomography, as performed in daily clinical practice, proved to be a powerful diagnostic tool in our subset of colorectal cancer patients.

Adult↗

PubMed1997

Effects of diagnostic application of monoclonal antibody on survival in melanoma patients.

Follow-up data of more than 300 melanoma patients were reviewed in which an immunoscintigraphy study had been performed as part of a routine staging protocol. All patients had received a commercially available 99mTc-labeled F(ab')2 fragment specific to a high-molecular-weight melanoma-associated antigen (HMW-MAA). Survival data of patients that had received one injection (group I) were compared with those receiving two or more injections (group II). For better comparison, patients were matched according to the following risk factors: (i) age, (ii) sex, (iii) tumor level according to Clark, (iv) tumor depth according to Breslow, (v) location of primary tumor, and (vi) metastases [and if positive, (vii) location of metastases]. Twenty-eight patient pairs were established that showed no statistically significant differences comparing the above-mentioned risk factors. In addition, no significant difference was found comparing the interval between primary diagnosis of disease and first injection of monoclonal antibody (MAb) in both groups. In contrast, survival time between first diagnosis of melanoma was significantly prolonged in group II (multiple injections) as compared to group I (single injection). This was true for survival time between primary diagnosis as well as from first injection of MAb until death or closing time of study. Our data suggest, that multiple injections of melanoma-specific F(ab')2 fragment have a beneficial effect on median survival in melanoma patients.

Adult↗

PubMed1997

Targeting peptides for pleural cavity tumor radiotherapy: specificity and dosimetry of Re-188-RC-160.

Re-188-RC-160, a radiolabeled somatostatin analogue, is being explored for its potential as a local/regionally administered radiotherapeutic agent targeting somatostatin receptor-positive tumors. In studies in vitro and in vivo, Re-188-RC-160 was found to bind to somatostatin receptor-positive cells (NCI-H69, human small cell lung carcinoma), but not to binding-negative cells (Raji, Burkitt's lymphoma). The comparative binding of Re-188-labeled RC-160 [cyclic NH2-(D)-Phe-Cys-Try-(D)-Trp-Lys-Val-Cys-Trp-NH2] or CTOP [cyclic NH2-(D)-Phe-Cys-Try-(D)-Trp-Orn-Thr-Pen-Thr-ol], a mu-opioid receptor antagonist used a negative control compound, was also determined in vitro and in vivo using NCI-H69 cells as targets. Re-188-RC-160 demonstrated higher net binding in vitro and in vivo compared to Re-188-RC-CTOP, and in vitro its binding could be reduced by excess unlabeled RC-160 whereas binding of Re-188-CTOP could not be reduced. Using another somatostatin receptor-positive human tumor line, ZR-75-1, a substantial amount of the cell-bound Re-188-RC-160 was found to be internalized. Does estimates for Re-188-RC-160 in animals containing NCI-H69 tumors indicated that with three serial injections therapeutic doses greater than 60 Gy can be achieved.

Animals↗

PubMed1997

Biodistribution of 125I-MAb 425 in a human glioma xenograft model: effect of chloroquine.

Chloroquine has been shown to increase the cellular retention and nuclear incorporation of 125I-labeled monoclonal antibody (MAb) 425, a murine anti-epidermal growth factor receptor monoclonal antibody, in human high-grade glioma cells in vitro. The objective of this study was to examine the effect of chloroquine on the biodistribution of 125I-MAb 425 in an intracerebral xenogeneic transplant of glioma cells. Nude rats were stereotaxically implanted in the right hemisphere with A1207 human high-grade glioma cells. After 14 days, animals were injected i.v. with chloroquine (40 mg/kg) followed 2 h later by an 125I-MAb 425 (9 MBq) infusion. Tissue distributions were performed up to 168 h post 125I-MAb 425 injection. From 24 to 168 h, tumor-to-contralateral left brain ratios increased from 9 to 15 for 125I-MAb 425 alone, and 7 to 13 for the 125I-MAb 425/chloroquine combination, respectively. A single administration of chloroquine did not result in any significant difference in radiolabeled MAb accumulation in either the tumor site or other tissues. We conclude that chloroquine did not increase the amount of 125I-MAb 425 into the tumor; however, it is safe to administer i.v. at the 40 mg/kg dose. Under these experimental conditions, the increased radioactive accumulation observed for in vitro data did not translate into similar in vivo results.

Animals↗

PubMed1997

Comparison of 18FDG-PET with 131iodine and 99mTc-sestamibi scintigraphy in differentiated thyroid cancer.

18Fluorine-fluorodeoxyglucose (FDG) positron-emission tomography (PET) has emerged as a useful method in various fields of oncology. The aim of the present study was to evaluate the clinical significance of this technique in differentiated thyroid carcinoma and to compare the results with other imaging modalities, particularly with whole-body 131iodine scintigraphy (WBS) and hexakis (2-methoxyisobutylisonitrile) (99m)technetium (I) scintigraphy (MIBI). Whole-body PET imaging using FDG was performed in 54 patients. There were 39 patients with papillary tumors and 15 patients with follicular tumors (including 3 Hürthle-cell carcinomas). Primary tumor stage (pT) was pT1 in 5 cases, pT2 in 19 cases, pT3 in 2 cases, pT4 in 24 cases, and unknown in 4 cases, respectively. Finally, for each case an overall clinical evaluation was done including histology, cytology, thyroglobulin level, sonography, computed tomography, magnetic resonance imaging, and subsequent clinical course, to allow a comparison with functional imaging results. Compared with WBS, FDG-PET gave different results in the majority of cases with recurrence/metastases (11 FDG-true-positive/WBS-negative tumor sites and 8 WBS-true-positive/FDG-negative tumor sites). In 7 patients with recurrence/metastases, FDG-PET and WBS gave corresponding results (10 sites). In 28 patients, FDG-PET and WBS were normal (including 2 false-negative cases). MIBI was performed in 44 cases. FDG-PET was better correlated to MIBI (congruent positive results in 13 tumor sites) than to WBS. Compared with MIBI, FDG-PET was superior in 5 cases (including 3 patients with distant metastases). Two FDG-negative/MIBI-positive tumors were observed. Different tracer uptake mechanisms have to be considered regarding "nonspecific" tumor imaging with FDG-PET or MIBI. Nevertheless, since spatial resolution with respect to tomographic imaging is inferior with single photon emission computer tomography (SPECT) using MIBI, the observed higher sensitivity of PET might be due to the higher spatial resolution of this method. As far as grading could be obtained, FDG-PET seemed to be more sensitive than WBS in high-grade tumors, whereas WBS was positive predominantly in low-grade carcinomas, although statistical significance could not be reached. The results prove the clinical usefulness of FDG-PET and MIBI for detection of 131iodine-negative tumor tissue in differentiated thyroid cancer.

Adult↗

PubMed1997

[PET scan in general practice for diagnosis of breast carcinoma].

The value of whole body positron emission tomography using 18F-fluoro-deoxy-glucose (18FDG) in primary work-up and follow-up was evaluated retrospectively in 104 patients with primary or metastatic breast cancer. Compared to other imaging methods, FDG-PET sensitivity was superior to sonography, CT or MRT. Another advantage is the possibility of whole body imaging and the earlier detection of lymph node metastasis due to the recognition of functional metabolic changes compared to structural changes found with conventional imaging methods.

Adult↗