Search PubMed⌕ Search

Biomedical subjects

H Ozkiliç

Publications and source records attributed to H Ozkiliç.

7 recordsLinked to original sources
PubMed2001

Correlation of 99mTc-sestamibi uptake with blood-pool and osseous phase 99mTc-MDP uptake in malignant bone and soft-tissue tumours.

Technetium-99m-sestamibi (99mTc-MIBI) imaging is a well-established modality in oncologic investigations. The current study aimed to investigate whether any relationship could be found between 99mTc-MIBI uptake and local perfusion in malignant bone and soft-tissue tumours. It also aimed to compare 99mTc-MIBI images with those of technetium-99m-methylene diphosphonate (99mTc-MDP) bone scintigraphy with regard to the activity distribution pattern, intensity and lesion extension. The study group included 24 patients with various bone and soft-tissue tumours. Three-phase bone scintigraphy and 99mTc-MIBI studies were performed within the same week before any surgical and therapeutic intervention. Images were evaluated visually and quantitatively using regions of interest (ROIs) over the lesion and adjacent normal tissue. The 99mTc-MIBI study was positive with varying degrees of uptake (range, 1.4-5.3). The mean 99mTc-MIBI uptake and 99mTc-MDP blood-pool and osseous phase activity ratios were 2.5 +/- 0.5, 2.8 +/- 1.0 and 5.5 +/- 4.0, respectively. The correlation between the 99mTc-MIBI uptake and blood-pool ratios was 0.70 (P<0.05). While activity distribution patterns were in agreement in 99mTc-MIBI and blood-pool images in the majority of cases, 99mTc-MIBI better delineated tumour viability and extension in five cases. In conclusion, 99mTc-MIBI accumulation shows a reasonable correlation with blood-pool uptake assuming the presence of multifactorial mechanisms in addition to local hyperaemia. Better delineation of tumour outlines and cellular activity seems to be an advantage of 99mTc-MIBI scintigraphy which may be helpful in the evaluation of musculoskeletal tumours.

Adolescent↗
PubMed1999

False-negative scintigraphy with Tc-99m sestamibi in stage IV neuroblastoma.

Tc-99m sestamibi, originally developed for myocardial studies, has been used as a tumor-seeking agent. Recently, the agent also was reported to be a functional tracer to predict multidrug resistance-related p-glycoprotein expression in tumor tissue. The current report presents the authors' experience with sestamibi tumor scintigraphy in a neuroblastoma. Although I-131 MIBG tumor imaging and Tc-99m MDP bone scanning accurately demonstrated the extent of the disease, Tc-99m sestamibi showed no accumulation in primary and metastatic foci. Lack of sestamibi uptake was initially thought to be suggestive of failure to respond to chemotherapy because of p-glycoprotein expression. However, the patient responded well to chemotherapy and complete remission was achieved. The failure of Tc-99m sestamibi to detect a neuroblastoma and the lack of sestamibi accumulation in the tumor may not always be related to chemotherapy resistance.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Assessment of chemotherapy-induced changes in bone sarcomas: clinical experience with 99Tcm-MDP three-phase dynamic bone scintigraphy.

The aim of this study was to evaluate the value of three-phase dynamic bone scintigraphy (TPBS) in the assessment of the response of bone sarcomas to pre-operative chemotherapy and to correlate serial scintigraphic changes with histological findings. The study group comprised 27 patients (osteogenic sarcoma, n = 20; Ewing's sarcoma, n = 5; malignant fibrous histiocytoma, n = 2) with a mean age of 19.2 years. All patients received 99Tcm-methylene diphosphonate TPBS before and after pre-operative chemotherapy. Each phase of the imaging procedure was interpreted qualitatively and quantitatively. The percentage of tumour necrosis was analysed on resection materials following surgery. Histologically, 12 patients were non-responsive (tumour necrosis less than 90%) and 15 patients were responsive (tumour necrosis more than 90%). A decrease in the tumour blood flow ratio and extension were the most notable findings in the responders. The mean change in the tumour blood flow ratio following therapy was 58.7 +/- 8.3% and 19.9 +/- 26.6% (P < 0.005) in responders and non-responders respectively. The accuracy of three-phase imaging and static bone scintigraphy was 88% and 74% respectively. Since bone scintigraphy is a valuable technique owing to its ability to detect distant metastases in clinically early disease, TPBS should be helpful in monitoring therapy effects without any additional cost or radiation dose.

Adolescent↗
PubMed1999

The role of 99Tcm-sestamibi scintigraphy in the staging and prediction of the therapeutic response of stage IV neuroblastoma: comparison with 131I-MIBG and 99Tcm-MDP scintigraphy.

In this study, we investigated prospectively the diagnostic role of 99Tcm-MIBI for staging and for predicting the therapeutic response of stage IV neuroblastoma compared with 131I-MIBG imaging and 99Tcm-MDP bone scintigraphy. Nine patients (4 girls and 5 boys aged 1-7 years) with suspected or proven stage IV neuroblastoma were studied with 99Tcm-MIBI at initial diagnosis and after 12-18 months of multidrug therapy. After the injection of 80 MBq.kg-1 99Tcm-MIBI, early (10 min) and delayed (1 h) images were obtained. The data were correlated with 131I-MIBG scans, bone scintigraphy, ultrasound, computed tomography and/or magnetic resonance imaging, and bone marrow biopsy. Eight of nine primary tumours and 41 metastatic lesions were detected by 131I-MIBG scintigraphy. None of the primary lesions demonstrated significant 99Tcm-MIBI accumulation. Sestamibi was positive in 16 of 41 MIBG-avid metastatic lesions. After six courses of multidrug chemotherapy, 30 131I-MIBI-avid neuroblastoma metastases that were 99Tcm-MIBI-negative at the time of diagnosis still did not show significant sestamibi accumulation. Follow-up demonstrated that all lesions that were 99Tcm-MIBI-avid at the time of diagnosis remained negative. Of these 16 lesions, seven were positive for 131I-MIBG accumulation with no reduction in size, and nine showed resolution after therapy. New metastatic foci detected by MIBG scintigraphy did not accumulate 99Tcm-MIBI. Clinical evaluation of patients with no 99Tcm-MIBI uptake in primary and secondary sites of neuroblastoma confirmed that they were resistant to multidrug chemotherapy. All 99Tcm-MIBI-positive lesions, irrespective of clinical outcome, demonstrated significant clearance of tracer on the delayed images. We conclude that 99Tcm-MIBI has no role in the staging of neuroblastoma. Sestamibi is a well-documented transport substrate for P-glycoprotein-related multidrug resistance and serial imaging may provide prognostic information on the therapeutic value of chemotherapy.

3-Iodobenzylguanidine↗
PubMed1994

Evaluation of palpable breast masses with 99Tcm-MIBI: a comparative study with mammography and ultrasonography.

We evaluated the feasibility of 99Tcm-methoxyisobutylisonitrile (MIBI) as a tumour localizing agent in patients with palpable breast masses in comparison with mammography and ultrasonography (US). Forty-one patients with palpable masses were studied. An additional 12 women with no palpable breast anomaly also underwent 99Tcm-MIBI breast study. Multiple views were obtained and semiquantitative evaluation was applied. Mammography and US revealed all of the malignant breast masses but differential diagnosis of fibroadenomas could not be achieved. Twenty-five of 27 breast carcinomas were detected using 99Tcm-MIBI scintigraphy. Two patients with invasive lobular carcinoma showed absent MIBI accumulation. Eight of 14 axillary lymph-node metastases showed positive uptake (57%). Twelve of 14 patients with pathologically proven benign breast lesions did not demonstrate any MIBI accumulation. Focal MIBI uptake could be observed in two fibroadenomas. The sensitivity and the specificity of semiquantitative MIBI analysis were 93 and 86%, respectively. Subjective grading offered no additional help in the further differentiation of malignant breast masses. There was no significant difference between histopathological types of breast carcinomas and uptake grades. Our results indicate that 99Tcm-MIBI scintigraphy may provide additional information in the differentiation of malignant pathologies from benign lesions in patients with palpable breast anomalies.

Adult↗