Nuri Arslan

Post-surgical ablation of thyroid remnants with high-dose 131I in patients with differentiated thyroid carcinoma

The aims of this study were to evaluate the efficacy of an empirically determined ‘fixed’ high ablative dose of radioiodine (131I) therapy and to determine the utility of ultrasonography (US) in dose determination. A retrospective analysis was performed of 242 thyroid cancer cases treated with ‘fixed’ high-dose 131I for ablation of thyroid remnants without a pre-ablative 131I diagnostic scintigraphy or radioiodine uptake study. Treatment doses ranged from 1850 MBq (50 mCi) to 7.4 GBq (200 mCi). The selection of the treatment dose was based on the surgical and pathological findings as well as the remnant thyroid volume calculated by US. A successful ablation was defined as the absence of activity in the thyroid bed on subsequent imaging studies. Successful ablation was obtained in 218 of the 242 patients (90%). In 162 of the 218 patients (74.3%), successful ablation was achieved after a single 131I treatment. The remnant thyroid volume calculated by US was significantly different (P = 0.04) between those who were successfully ablated and those who were not. The total 131I dose needed for successful ablation was significantly higher in males (P = 0.003). Patients with higher post-operative thyroglobulin (Tgb) levels and patients with a higher stage of disease required higher doses (P = 0.036 and P = 0.021 respectively). Serum Tgb levels were under 10 ng·ml−1 in 220 of the 242 patients (90%) following radioiodine ablation while not receiving L-thyroxine suppression. Nineteen patients (7.8%) showed metastases on post-therapy scan and successful treatment was achieved in 11 of 19 (57.8%). Four of the 19 patients with distant metastases (revealed on post-treatment scan) were found to have been given a treatment dose of less than 200 mCi based on the proposed empirical approach. These results indicate that ‘fixed’ high-dose 131I treatment is clinically feasible with an acceptable dose underestimation rate, and the utilization of US in the determination of the thyroid remnant volume provides more accurate and reproducible results.

Comparison of In-111 octreotide and Tc-99m (V) DMSA scintigraphy in the detection of medullary thyroid tumor foci in patients with elevated levels of tumor markers after surgery.

Purpose In this retrospective study, the authors evaluated the utility of In-111 octreotide (OctreoScan) and Tc-99m (V) DMSA scintigraphy for the localization of recurrent metastatic tumor foci in patients with medullary thyroid cancer (MTC) and compared the findings with those of conventional radiologic imaging methods. Methods The scintigraphic images were compared with computed tomography (CT) and magnetic resonance imaging (MRI) and ultrasonography (US) in 14 patients (8 men, 6 women; age range, 22 to 74 years) with elevated calcitonin and carcinoembryonic antigen levels after total thyroidectomy. All scintigraphic image findings were evaluated qualitatively as mild uptake (+) and moderate to marked uptake (++). Results In-111 octreotide may be superior to Tc-99m (V) DMSA for the detection of tumor foci of patients with MTC on a patient basis (78.5% versus 57.1%) and on a lesion basis (44.1% versus 30.2%). The sensitivity rate for In-111 octreotide (78.5%) was also similar to that of CT and MRI on a patient basis. Conversely, the combined use of Tc-99m (V) DMSA and In-111 octreotide revealed the best sensitivity rate (85.7%) on a patient basis, whereas the combined use of CT and MRI showed the best sensitivity rate (81.3%) on a lesion basis. Conclusions These findings suggest that In-111 octreotide is superior to Tc-99m (V) DMSA and has a similar sensitivity rate to CT and MRI for the diagnosis of recurrent or metastatic MTC. Although the combined use of In-111 octreotide and Tc-99m (V) DMSA was most sensitive, the combined use of CT and MRI with radionuclide imaging methods may better detect more metastatic tumor foci.

99Tcm-MIBI scintimammography in the evaluation of breast lesions and axillary involvement : A comparison with mammography and histopathological diagnosis

The aim of this prospective study was to determine the diagnostic value of prone lateral 99Tcm-MIBI scintimammography in the detection of primary breast cancer and axillary lymph node involvement in patients with breast lesions. We evaluated 83 palpable and 22 non-palpable lesions in 77 consecutive patients with a clinically palpable mass and/or suspicious mammographic finding. Early and late scintimammograms were performed after the intravenous injection of 740 MBq 99Tcm-MIBI. The overall sensitivity of both scintimammography and mammography in the detection of primary breast cancer was 94%. The overall specificity was 84% and 56% for scintimammography and mammography respectively. In the patients with palpable masses, the sensitivity of scintimammography was 97% and the specificity was 84%; in those with non-palpable masses, the sensitivity was 35% and the specificity 100%. For the detection of axillary lymph node involvement, the sensitivity and specificity of scintimammography were 68% and 93% respectively. However, conventional mammography showed 37% sensitivity and 86% specificity. In conclusion, scintimammography is an accurate and clinically valuable tool for evaluating palpable and non-palpable breast abnormalities. In addition to its high sensitivity, it improves the specificity of mammography both in the evaluation of breast masses and in the detection of axillary involvement.

Utility of ventilation and perfusion scan in the diagnosis of young military recruits with an incidental finding of hyperlucent lung.

Swyer-James-MacLeod syndrome (SJMS) is considered to be a relatively uncommon disease presenting with unilateral hyperlucent lung due to hypoplasia of a pulmonary artery and bronchiectasis of the affected lung. In this report, we describe the ventilation-perfusion (V/Q) scan findings of nine male recruits (aged 20-29 years, mean 24.4±2.96 years) with SJMS in whom the diagnosis was first established in adulthood. V/Q scan findings of all patients were compared with those on planar radiographs, pulmonary function studies, high resolution computed tomography (HRCT) and digital subtraction angiography (DSA). The ventilation (133Xe) and perfusion (99Tcm-macro-aggregated albumin) scans showed the characteristic pattern of a matched V/Q defect and marked air trapping on the washout phase on 133Xe scintigraphy. HRCT displayed hypodense lung with integrity of main airways, and markedly diminished vasculature on the affected side in all patients. A smaller pulmonary artery on the affected side with poor peripheral vasculature was observed with DSA in all patients. All patients had features of obstructive airway disease in varying degrees on pulmonary function studies. In contrast to other imaging methods, bronchiectasis as an etiological factor was displayed on HRCT. Some pulmonary areas, which were normal on HRCT and planar radiographs, showed air trapping on V/Q scan. Although a V/Q scan was more helpful in determining the extent of the disease and correlates well with conventional imaging methods, HRCT was the most valuable imaging method for the evaluation of aetiology in unilateral hyperlucent lung.

Cerium nitrate treatment prevents progressive tissue necrosis in the zone of stasis following burn

Cerium nitrate (CN) was used as a topical antiseptic agent for the treatment of burn wounds and found to reduce the number of anticipated death in burn. This decreased burn related mortality cannot be explained by the control of wound infection alone. In the studies performed to elucidate the unexplained effects of CN treatment, it was shown that CN treatment reduced the alarm cytokine levels, decreased leukocyte activation, reduced macromolecular leakage and finally burn edema formation. We hypothesized that CN treatment prevents the conversion of the zone of stasis to progressive tissue necrosis by decreasing leukocyte activation and reducing macromolecular leakage and burn edema. This was investigated on a well-described burn comb model in the rats. Fifty-four rats were randomly divided into control and CN treatment groups. Each rat in CN treatment group received 0.04 M CN bathing 30 min after burn whereas rats in control group received 0.09% saline bathing. Viability of zone of stasis is assessed with (99 m)Tc-sestamibi scintigraphy. Nine rats in each group were scintigraphically evaluated at the 3rd and 7th day after burn and remaining 9 rats had macroscopic and histological examination at the 21st day after burn to confirm the scintigraphic results. In CN treatment groups, the scintigraphic uptake ratios were higher both at post burn day 3rd and 7th when compared to that of control groups. This was statistically significant (p≤0.05). In the CN treatment group, the results of the average percentage of the re-epithelialization in the zone of stasis were higher than that of control groups. The difference between the groups was also statistically significant (p≤0.05). These results were accepted that CN treatment prevents progressive tissue necrosis in the zone of stasis. This study further elucidates the unexplained effects of CN treatment on burn.

Unusual patterns of I-131 contamination

Whole body imaging with radioiodine can detect functioning metastases, which can often be effectively treated with appropriate amounts of radioiodine. Non-physiologic I-131 uptake detected on images is usually interpreted as suggesting functioning thyroid metastases. However, extra-thyroidal I-131 accumulation does not always imply thyroid cancer metastases and has been reported on many occasions, including various non-thyroidal neoplasms, and contamination by body secretions. In order to avoid unnecessary therapeutic interventions it is extremely important to properly distinguish false-positive sites of I-131 localization. Three patients with unusual radioiodine contamination patterns, either presented for the first time or rarely presented in the existing literature, were reported. Reported cases consist of contamination in hair (due to styling hair with sputum), contamination in neck (due to drooling during sleep) and, contaminated chewing gum. False positive contamination sources were clarified by careful examination of patients and further images when necessary.

Detection of widespread neurolymphomatosis with 18F-FDG PET

Brain MRI of a 21-year-old male with diffuse large B-cell lymphoma revealed lymphomatous infiltration in bilateral cavernous sinuses and fifth cranial nerves. Whole-body F-FDG PET revealed increased FDG uptake in the entire left brachial (a, left: solid arrow) and right lumbosacral plexus (middle), the proximal portion of the left lumbosacral plexus and areas around the cervical cord (a, left: dotted arrow). There was also increased FDG uptake in the spinal and sacral canal from T12 through the sacrum (a, right: solid arrow) as well as in multiple vertebrae, including the axis, C6 (a, right: dashed arrow), T5 and T11. In contrast, hypometabolism was noted in the L2 vertebral body (a, right: dotted arrow). MRI evaluation of these abnormal sites demonstrated enlargement and thickening of the right lumbosacral plexus, left proximal lumbosacral plexus (b, left) and left brachial plexus (b, middle). Dural thickening at the level of C6 through T2 was also noted. Diffuse leptomeningeal and dural infiltration obscured the conus medullaris and cauda equina from T12 to the sacral canal. MRI also depicted low T1 and high T2 signal intensity in the bone lesion in the L2 vertebral body (b, right). The infiltrated neural plexus, lumbar dura and bone lesion were enhanced mildly on intravenous contrast-enhanced series. These concordant PET and MRI findings suggested widespread neurolymphomatosis. Neurolymphomatosis is a rare neurological manifestation of systemic lymphoma [1]. The diagnosis is often difficult during lifetime and usually requires nerve biopsy [2]. Only a few case reports exist that show findings of neurolymphomatosis on CT, MRI and PET [3–5]. Although histopathological confirmation was unavailable, the concordant PET and MRI findings and the known systemic and cranial nerve involvement in this patient strongly suggest that the lesions were due to neurolymphomatosis. This approach to diagnosis is in concordance with the suggestions of Baehring et al.: in their extensive review, they added a surrogate criterion for neurolymphomatosis, in the form of CT, MRI or intraoperative evidence of nerve infiltration beyond the dural sleeve in the setting of known central nervous system or systemic lymphoma [6]. Emel Öztürk ()) Department of Nuclear Medicine, Gülhane Military Medical Academy and Medical School, 06018 Etlik, Ankara, Turkey e-mail: eozturk@gata.edu.tr Tel.: +90-312-3044806; Fax: +90-312-3044800

Use of CA15-3, CEA and prolactin for the primary diagnosis of breast cancer and correlation with the prognostic factors at the time of initial diagnosis

The main goals of the clinical use of tumor markers are to evaluate the adequacy of the treatment, monitor recurrence and follow up response to the treatment applied. For this purpose a baseline level for the commonly used tumor marker must be known at the time of initial diagnosis, before any therapy, in order to compare with the tumor marker levels which will be obtained after the treatment and during the clinical follow-up. The aim of this study was to investigate the correlation, if there is any, of the baseline levels of CA15-3, CEA and prolactin (PRL) in patients with breast cancer with the most commonly used prognostic factors, i) the presence of distant metastasis, ii) the presence of axillary lymphatic invasion, iii) the number of invaded axillary lymph nodes, iv) tumor size and v) stage of the disease, for breast cancer. Baseline serum CA15-3, CEA and PRL levels of 172 patients with breast masses were determined prior to biopsy. The sensitivity and specificity of baseline CA15-3, CEA and PRL were; 23.2% and 95.3%, 17.4% and 83.7%, 5.8% and 97.6%, respectively. At least one of the three tumor markers was high in 36% (31/86) of the breast cancer patients. Baseline CA15-3 levels were frequently higher than CEA in patients with bone metastasis (60% vs. 20%) and axillary lymphatic invasion (31.8% vs. 25%), and showed a better correlation with the stage of disease. Baseline tumor marker levels showed no statistically significant correlation with either the number of invaded axillary lymph nodes or tumor size. In conclusion, sensitivities and negative predictive values for baseline CA15-3, CEA and PRL were not satisfactory for primary diagnosis of breast cancer. Correlation of baseline CA15-3 was found superior to CEA and PRL in terms of stage of disease, presence of axillary invasion and distant metastasis.

Detection of a recurrent parathyroid carcinoma with FDG positron emission tomography.

Primary hyperparathyroid disease is a relatively common endocrine disorder caused by parathyroid adenoma, chief cell hyperplasia or, rarely, parathyroid carcinoma. Parathyroid carcinoma accounts for approximately 0.14% of cases of primary hyperparathyroid disease. Surgical resection is the mainstay of therapy in these patients. Diagnosis is established biochemically by detection of elevated serum parathyroid hormone (PTH) and calcium concentrations. Although multiple imaging methods, such as computed tomography (CT), ultrasonography, magnetic resonance imaging (MRI), and Tc-99m sestamibi scintigraphy, can be used to examine patients with hyperparathyroid disease, their use for preoperative localization of abnormal parathyroid glands before first-time exploration remains controversial. However, most investigators agree that imaging, particularly Tc-99m sestamibi scintigraphy, is helpful for planning repeated surgery in patients with recurrent hyperparathyroid disease. Positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG), however, has also been used for preoperative localization of abnormal parathyroid glands. This report addresses the use of FDG PET to detect parathyroid carcinoma.

Abnormal 18F-FDG Uptake Detected with Positron Emission Tomography in a Patient with Breast Cancer: A Case of Sarcoidosis and Review of the Literature

18F-FDG PET is a useful and sensitive imaging method for a variety of malignancies, however, the specificity is low in active infections and inflammatory diseases. We describe a female patient with stage IIIA breast cancer in first complete remission with combination chemotherapy who developed nodular formations in the lung and axilla 12 years later. Imaging studies as well as FDG PET showed nodular lesions and increased metabolic activity which was interpreted as the progression of the primary disease. She was first given combination chemotherapy and hormonal therapy but was proven thereafter to have sarcoidosis by pathologic examination and was successfully treated with corticosteroid treatment.