Umut Elboga

Multiple muscle metastases from lung cancer detected by FDG PET/CT.

A 71-year-old man with right lung mass, who was recently diagnosed histopathologically with pulmonary adenocarcinoma, was referred for staging of the primary tumor. Whole-body F-18 fluorodeoxyglucose positron emission tomography and computed tomography (FDG PET/CT) demonstrated multiple hypermetabolic foci in various skeletal muscle localizations, suggesting extensive metastatic muscle involvements in addition to increased FDG uptake in the primary tumor. Subsequent biopsy and histopathological study confirmed muscle metastasis from lung adenocarcinoma. Skeletal muscle metastasis from lung cancer is rare, but multiple muscle metastases are even more unusual. FDG PET/CT is able to detect unexpected metastatic involvements such as multiple muscle metastases in lung cancer patients.

The role of FDG PET-CT in differential diagnosis of pleural pathologies

OBJECTIVE This study has aimed to evaluate the impact of (F18) Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (FDG PET-CT) in the differential diagnosis of malignant and benign pleural lesions in patients with suspected malignant pleural mesothelioma (MPM). MATERIAL AND METHODS Fifty patients (32 females, 18 males; age range 24-79 years) with pleural thickening, fluid, plaques or calcification on previous CT scan were examined with FDG PET-CT. PET-CT imaging was obtained 1 h after FDG injection. In 12 patients, delayed imaging from the thoracic region was performed 2 h after injection. FDG uptake was evaluated visually and semiquantitively using standardized uptake value (SUV). FDG PET-CT findings were compared with histopathologic diagnosis. RESULTS Thirty-nine patients had increased FDG uptake in pleural lesions but PET-CT results were negative in 11 patients. When compared with histopathological results in FDG positive group, 34 patients had MPM, 5 had benign pathology; in FDG negative group 8 patients had benign pathology, 3 had MPM. Of patients with delayed imaging, 9 showed increased SUV but 3 had a decreased SUV on delayed images. Increased SUV group had 4 MPM, 5 benign pathology (3 chronic granulomatous inflammation, 2 benign asbestotic plaque). Decreased SUV group all had benign pathology (fibrosis, chronic inflammation, myofibrosis). DISCUSSION FDG PET-CT is a useful imaging modality in differential diagnosis of malignant and benign pleural lesions. Delayed imaging seems to be useful if there is a decrease in SUV suggesting a benign pathology but does not seem to contribute to the differential diagnosis if the SUV is increased.

Evaluation of conventional imaging techniques on preoperative localization in primary hyperparathyroidism

We aimed to evaluate the diagnostic and preoperative localization capacity of 99mTc methoxyisobutylnitrile (MIBI) parathyroid scintigraphy and ultrasonography (USG) in enlarged parathyroid glands in the primary hyperparathyroidism (pHPT) as well as the relationship between the success rate of these techniques and biochemical values. In this study, we retrospectively evaluated 39 patients with clinical and biological evidence of pHPT who referred to the university hospital for MIBI parathyroid scintigraphy. Patients were examined with USG and double-phase MIBI parathyroid scintigraphy for the detection of enlarged parathyroid glands. Preoperative serum intact parathyroid hormone (iPTH) levels, calcium (Ca), phosphate and alkaline phosphatase measurements were obtained. A total of 45 parathyroid lesions in 39 patients were reviewed. Thirty-four patients had a single adenoma and 5 patients with multi-gland disease had 11 abnormal parathyroid glands including three adenomas, whereas the remaining 8 glands showed hyperplasia. The overall sensitivities of MIBI parathyroid scintigraphy, USG and combined techniques were 85.3%, 72.5% and 90.4%, respectively; the positive predictive values (PPV) were 89.7%, 85.2% and 92.6%, respectively. The most successful approach for detection of enlarged parathyroid glands in hyperparathyroidism is the concurrent application of USG and MIBI parathyroid scintigraphy modalities. The concomitancy of thyroid diseases decreases the sensitivity of both MIBI parathyroid scintigraphy and USG in enlarged parathyroid glands.

FDG PET/CT appearance of multicentric Castleman's disease mimicking lymphoma

We report a case of a multicentric form of Castlemans disease with multiple lymph nodes showing intense FDG uptake on whole body scan mimicking non-Hodgkins lymphoma. In this report, the patient had multiple cervical, mediastinal, hilar, retroperitoneal and abnormal lymph nodes in the groin. (18)F-fluorodeoxyglucose positron emission tomography/computed tomography was performed before tissue sampling. (18)F-FDG/PET demonstrated multiple areas of increased uptake in cervical, mediastinal, hilar, retroperitoneal and groin lymph nodes, suggesting a generalized disease of the lymphatic system including non-Hodgkins lymphoma. The final diagnosis is based on the histopathological findings of the material obtained from the cervical lymphadenectomy. The histological diagnosis was multicentric plasma cell variant of Castlemans disease. (18)F fluorodeoxyglucose positron emission tomography/computed tomography scan helped to identify the lymph nodes involved throughout the whole body, but did not help to differentiate non-Hodgkins lymphoma. The clinical conclusions and PET/CT findings are described in this report.

A rare tumor: tracheal Ewing's sarcoma.

A 70-year-old man, with renal failure, applied with the complaint of shortness of breath. Thoracic computed tomography revealed dense intraluminal fields at distal trachea. The bronchoscopy revealed a solid mass, located on the lateral wall of the trachea (Fig. 1). During bronchoscopy, an endobronchial mass excision with laser was performed. The immunohistochemical examination revealed that the tumor cells reacted positively to vimentin and friend leukemia integration (FLI)-1, and negatively to desmin, CD31, S-100, and pancytokeratin (Figs. 2 and 3). The findings were consistent with ES. Due to the suspicions concerning the surgical margin, radiotherapy (RT) was recommended. Postoperatively, 50.4-Gy RT was applied. Metastatic lesions in the scalp and humerus were revealed 3 months after the RT. Chemotherapy could not be performed because of the renal insufficiency. The patient died 8 months after surgery due to renal failure.

Lung metastases in patients with differentiated thyroid carcinoma and evaluation of response to radioiodine therapy

INTRODUCTION The most common site of metastases in differentiated thyroid carcinomas is the lungs. In our study, we aimed to determine the ratios of lung metastases in patients with differentiated thyroid carcinoma and response to radioiodine therapy. MATERIAL AND METHODS A total of 542 patients with differentiated thyroid carcinoma who were admitted to our clinic were included in the study. High doses of (131)I were administered to the patients with lung metastases. Response to therapy were evaluated with (131)I scans and stimulated serum Tg levels were examined at least 6 months after therapy. RESULTS Lung metastases were detected in 17 (3.1%) of 542 patients with differentiated thyroid carcinoma. Of these patients to whom high doses of (131)I therapy were administered, complete response to therapy was obtained in 5 (29.4%), partial response was obtained in 3 (17.6%) and no response could be obtained in 9 (53%) patients. CONCLUSION Although lung metastases from differentiated thyroid carcinomas are rare, those are more common in advanced ages and in males. High doses of (131)I therapy may be partially beneficial in these patients. Thus repetition of therapy is frequently required.

Axillary lymph node metastasis of papillary thyroid carcinoma detected by FDG PET/CT in a thyroglobulin-positive patient with negative whole-body 131I scan.

Axillary metastasis is not a common finding in papillary carcinoma. 18F-FDG can detect foci of metastasis in patients with negative 131I scan. We report a case of a 64-year-old man who had undergone thyroidectomy and 131I ablation due to classic type of papillary carcinoma 14 years ago. Follow-up examination revealed high serum thyroglobulin and negative whole body 131I scan. 18F-FDG PET/CT showed focally increased uptake in right axillary as well as supraclavicular and bilateral cervical lymph nodes. Histopathological examination of the surgically removed lymph nodes confirmed the metastasis of papillary thyroid carcinoma.

Lu-177 labelled peptide treatment for radioiodine refractory differentiated thyroid carcinoma

Differentiated thyroid carcinoma (DTC) has good prognosis but 5% of the patients already have distant metastasis at the diagnosis. Tumour cells can lose their iodine uptake ability and enter a state of dedifferentiation. Treatment for differentiated thyroid carcinoma that is not suitable for the local surgery and unresponsive to radioactive iodine uptake is not always easy for physicians. We present a case of a 64-year-old man who had total thyroidectomy surgery and central lymph node dissection with diagnosis of multinodular goitre disease. Histopathological evaluation was papillary thyroid cancer with tall cell variant. Treatment using 150 mCi radioiodine was administered to the patient three times but could not effect a cure. We performed Ga-68 labelled DOTATE (synthetic somatostatin analogue peptide). This provided a good outcome. As evident from our case, Lu-177 radionuclide labelled synthetic somatostatin analogue peptides have therapeutic effect on radioiodine refractory DTC, as an alternative treatment modality.

The relationship between thyroglobulin (Tg) levels and distant metastases before radioiodine (RAI) treatment in differentiated thyroid carcinomas

The aim of our study is to determine the relationship between distant metastases and thyroglobulin (Tg) levels measured before radioiodine (RAI) treatment in differentiated thyroid carcinomas. Sixty seven patients with near total or total thyroidectomy were included in the study. Fifty patients did not have lymph node or distant metastases (Group 1), and 17 patients had distant metastases (Group 2). Tg and anti-Tg levels of these patients were measured before RAI treatment when TSH>30 mU/l. Serum Tg levels were found 8,5±10,6 ng/ml and 307±142 ng/ml in Group 1 and Group 2, respectively. There was a significant difference between the mean Tg levels of Group 1 and 2 (p

Long-term survival with transarterial chemoembolization and radioembolization in a patient with cancers of unknown primary

Cancers of unknown primary (CUP) are histologically proven metastatic malignant tumors without an identified primary site before treatment. The common characteristics are early dissemination, lower response to chemotherapy and poor prognosis with short life expectancy. Treatment was directed according to the presence of localized or disseminated disease. The most frequent site of metastasis is the liver, which is a suitable target organ for arterial-directed therapies. We report a case of 53-year-old woman who was diagnosed with CUP and suspected with intracellular cholangiocellular carcinoma (ICC), presented with a very large, unresectable, chemotherapy-refractory hepatic mass and treated with transarterial chemoembolization and transarterial radioembolization and surprisingly followed for 48 months with minimally progressive and stable disease. Arterial-directed therapies, an important therapeutic option in unresectable liver tumors, can provide survival benefit even for ICC and CUP which are very large in size.