Sertac Asa

Clinical value of technetium-99m-labeled octreotide scintigraphy in local recurrent or metastatic medullary thyroid cancers: a comparison of lesions with 18F-FDG-PET and MIBI images.

AimVarious studies have been conducted for determining the most optimal method for the early diagnosis of local recurrent or distant metastatic thyroid cancers. The aim of this study was to evaluate the clinical utility of technetium-99m (Tc-99m)-labeled octreotide derivatives in the detection of recurrence or distant metastases in medullary thyroid cancer patients and to compare the lesions with those detected using 18F-fluorodeoxyglucose (18F-FDG)-PET and Tc-99m MIBI studies in the same patient group. Patients and methodsSixteen medullary thyroid cancer patients [two male and 14 female; mean age 52.0±14.1 years (range 13–72 years)] were included in this study. All patients underwent a whole-body scan 1 and 4 h after injection with octreotide derivatives and single photon emission computed tomography images were taken of the sites suspicious for metastasis. The lesions seen in Tc-99m HYNIC octreotide studies were compared with those seen in 18F-FDG-PET and Tc-99m MIBI studies. ResultsAmong the Tc-99m-labeled octreotide scintigraphy studies, nine were evaluated as true positive (56.2%) and one was evaluated as false positive (6.2%); six were false negative (37.5%). In 16 patients, the total number of lesions seen on octreotide scintigraphy was 21. Thirteen of the 16 patients underwent 18F-FDG-PET imaging. Of the 13 patients studied, 10 showed true-positive (76.9%) and three showed false-negative (23.1%) results. The total number of lesions seen on 18F-FDG-PET was 23. The Tc-99m MIBI study yielded positive results in seven of 16 patients (43.7%) and negative results in nine patients (56.3%). The total number of lesions on Tc-99m MIBI was 12. ConclusionThe Tc-99m-labeled somatostatin receptor scintigraphy analogs HYNIC-tyrosine octreotide and HYNIC-TATE are useful imaging alternatives in somatostatin receptor-expressing thyroid cancers. Radiolabeling using these analogs is easy and they are readily available for routine use.

FDG PET/CT in the detection of metastases in a patient with Tg and 131I WBS negative follicular thyroid cancer.

After a total or near total thyroidectomy and radioiodine ablation therapy for differential thyroid cancer (DTC), routine follow-up methods are (131)I or (131)I whole-body scanning (WBS) as well as serum thyroglobulin (Tg) and anti-thyroglobulin (anti-Tg) levels. We describe a case of a 41-year-old woman with follicular thyroid cancer. Although serum Tg level and (131)I WBS were negative after radioiodine ablation therapy, she had pain around her left medial clavicle. FDG PET/CT was performed for any undetected metastases. FDG PET/CT showed hypermetabolic bone metastases in the left medial clavicle. Biopsy confirmed metastases of the thyroid follicular carcinoma.

Prognostic significance and predictive performance of volume-based parameters of F-18 FDG PET/CT in squamous cell head and neck cancers

AIM It has been previously reported that metabolic tumor volume on positron emission tomography-computed tomography predicts disease recurrence and death in head-and-neck cancer. In this study, we assessed the prognostic value of metabolic tumor volume measured using F18-Fluorodeoxyglucose PET/CT in patients with head and neck squamous cell carcinoma. MATERIALS AND METHODS We analyzed the imaging findings of 74 patients (age 57±16) retrospectively, with head and neck cancer who underwent PET/CT scan for staging and after treatment. Forty-tree patients had nasopharynx, 15 patients had hypopharynx, 9 patients had larynx, and 7 patients had oropharynx cancer. The MTVs of primary sites with or without lymph nodes were measured, and outcomes were assessed using the treatment response evaluation by the Response Evaluation Criteria in Solid Tumors and recurrence events during follow-up. RESULTS A total of 48 patients had complete response or no recurrence was detected as of in the last follow-up. Of the first PET/CT scan, the median primary tumor SUVmax was 18.8 and the median nodal SUVmax was 13.4. The median primary tumor MTV% 50s ranged from 11.12 cm3 to 16.28 cm3, and the MTV after the therapy ranged from 1.18 cm3 to 3.51 cm3. CONCLUSION Metabolic tumor volume (MTV) represents tumor burden, which shows F18-Fluorodeoxyglucose uptake and has a potential value in predicting short-term outcome and disease-free survival in patients with head and neck cancer.

Appearance of recurrent cardiac myxofibrosarcoma on FDG PET/CT.

Primary cardiac sarcomas are extremely rare tumors. In this case report, we presented the condition of a 37-year-old male patient diagnosed with myxofibrosarcoma after histopathologic evaluation of the left atrium mass excision. FDG PET/CT was performed and showed recurrent hypermetabolic lesions in the left atrial wall and right anterior mediastinal region.

The different distribution patterns of FDG and FDG-labelled WBC in inflammatory and infectious lesions

A 56-year-old woman with a 1 year history of right knee prosthesis and right ankle cyst resection was referred for right ankle pain and skin lesion on the right ankle. The patient also had an iliac bone graft operation for talar bone defect. The patient underwent whole-body fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT and FDG-labelled white blood cell (WBC) scan for diagnosis of the infection. The interval between the two studies was 1 day. FDG PET/CT images showed a soft tissue lesion

Accuracy of FDG-PET/CT and paraneoplastic antibodies in diagnosing cancer in paraneoplastic neurological syndromes

OBJECTIVE There is still no consensus about whether to perform PET/CT to detect carcinoma in paraneoplastic neurological syndromes (PNS) in patients with or without antibodies. The aim of this study is to determine the diagnostic accuracy of PET/CT and antibodies in patients with PNS. MATERIAL AND METHODS A retrospective study was conducted on patients with clinically suspected PNS between 2008 and 2013. The association between histopathological findings, paraneoplastic antibodies, and PET/CT findings were evaluated. Sensitivity and specificity for the detection of underlying malignancy were calculated for PET/CT and paraneoplastic antibodies. RESULTS A total of 42 patients were analyzed. Of these 42 patients, 32 (75%) had a classical PNS, 6 (14%) had positive PET/CT findings, and 34 were tested for the presence of antibodies (anti-Hu Ab, anti-Yo Ab, and anti-Ri Ab). Twenty one of 34 patients had positive antibodies. Of the 6 patients with positive PET/CT findings, 6 had positive histopathological results. Among 21 patients with positive biomarkers, carcinoma was confirmed only in 5 patients. One patient with negative antibodies, but positive PET/CT findings, was diagnosed with a tumor. Gastric carcinoma was detected in 1 patient with negative PET/CT findings and antibodies during follow-up. Based on the results, PET/CT was found to have 85.71% sensitivity, 100% specificity, 100% positive and 97.22% negative predictive values in the detection of tumors. CONCLUSION PET/CT has a certain diagnostic accuracy for detecting underlying malignancy in patients with PNS, regardless of the presence of paraneoplastic antibodies.

FDG PET/CT in Peritoneal Metastasis From Prostate Cancer.

Prostate cancer is one of the leading causes of cancer death in men. The prognosis in prostate cancer is greatly worsened by the presence of metastases, which are most commonly found in bone, lung, liver, and brain. The peritoneum is an extremely uncommon metastatic site for prostate cancer, even in autopsy series. We present a case of FDG PET/CT demonstration of peritoneal metastasis from prostate cancer.

Primary spinal leptomeningeal gliomatosis in a 3-year-old boy revealed with MRI and FDG PET/CT mimicking tuberculosis meningitis.

A 3-year-old boy was referred to neurologist for inward devition of his left eye, weakness, lack of appetite, headache and ehavioral change. On physical examination, the findings of ilateral abducens nerve paralysis were noted. Cranial magnetic esonance imaging (MRI) revealed diffuse leptomeningeal contrast nhancement at the supra-infratentorial regions predominantly nvolving the basal cisterns and also hydrocephalus and initially uggesting basilar meningitis. Cerebrospinal fluid (CSF) studies howed normal glucose and elevated protein levels but no tumor ells. No growth was detected in any of the bacterial cultures ncluding acid-resistant bacteria. The patient was started on oral nti-tuberculosis medication and corticosteroid treatment with he presumed diagnosis of tuberculosis meningitis and a ventricuoperitoneal (VP) shunt was inserted due to hydrocephalus. After months of treatment, the patient was re-admitted to hospial with vomiting, convulsion and confusion. Cranial MRI showed he similar findings to previous one, and spinal MRI depicted iffuse leptomeningeal contrast enhancement as well as microystic changes along the spinal cord (Fig. 1). Histopathology of the ural biopsy material revealed widespread glioma infiltration of he subarachnoid space suggestive of leptomeningeal gliomatosis. his patient with unknown primary was referred for FDG PET/CT. nder child sedation, brain and whole body non-contrast enhanced ET/CT images were obtained 90 min after the intravenous injecion of 148MBq (4mCi) 18F FDG using a Biograph 6 PET/CT. The can depicted slightly increased FDG uptake (SUVmax 2.1)along the pinal cord without any other FDG-avid primary tumor. The patient as started on chemotherapy including vincristine and carboplatin Figs. 2 and 3). His symptoms were relieved after completion of hemo. Primary diffuse leptomeningeal gliomatosis (PDLG) is a rare isease thought to arise from isolated astrocytic cell nests also nown as heterotropic neuroglial tissue within the leptomeninges HLNT) in the subarachnoid space. The HLNT can transform into two

FDG PET/CT in monitoring treatment of retroperitoneal fibrosis

Retroperitoneal fibrosis is an uncommon disease characterized by inflammatory fibrosis typically surrounding abdominal aorta and iliac arteries. The glucose analogue F18-fluorodeoxyglucose can be used to image inflammatory cell activity non-invasively by PET. In this report we investigated the usefulness of the FDG PET/CT in the disease activity and therapy response evaluation of retroperitoneal fibrosis.

Initial evaluation of inflammatory breast cancer with fluorodeoxyglucose positron emission tomography

Inflammatory breast cancer (IBC) is the most aggressive form of locally advanced breast cancer. We present here 18F FDG PET/CT findings of two patients with IBC. These patients were referred to the Nuclear Medicine department for staging of IBC. FDG PET/CT images showed diffuse infiltration of breasts with multiple lymph nodes and multiple metastases in whole-body PET/CT images. FDG PET provides additional information regarding lymph nodes or distant metastases in the initial evaluation of IBC.