Linear accelerator-based stereotactic radiosurgery in recurrent glioblastoma: A single center experience

Background/Aim. Management of patients with recurrent glioblastoma (GB) comprises a therapeutic challenge in neurooncology owing to the aggressive nature of the disease with poor local control despite a combined modality treatment. The majority of cases recur within the highdose radiotherapy field limiting the use of conventional techniques for re-irradiation due to potential toxicity. Stereotactic radiosurgery (SRS) offers a viable noninvasive therapeutic option in palliative treatment of recurrent GB as a sophisticated modality with improved setup accuracy allowing the administration of high-dose, precise radiotherapy. The aim of the study was to, we report our experience with single-dose linear accelerator (LINAC) based SRS in the management of patients with recurrent GB. Methods. Between 1998 and 2010 a total of 19 patients with recurrent GB were treated using single-dose LINAC-based SRS. The median age was 47 (23-65) years at primary diagnosis. Karnofsky Performance Score was ≥ 70 for all the patients. The median planning target volume (PTV) was 13 (7-19) cc. The median marginal dose was 16 (10-19) Gy prescribed to the 80%-95% isodose line encompassing the planning target volume. The median follow-up time was 13 (2-59) months. Results. The median survival was 21 months and 9.3 months from the initial GB diagnosis and from SRS, respectively. The median progression-free survival from SRS was 5.7 months. All the patients tolerated radiosurgical treatment well without any Common Toxicity Criteria (CTC) grade > 2 acute side effects. Conclusion. Single-dose LINAC-based SRS is a safe and well- tolerated palliative therapeutic option in the management of patients with recurrent GB

Is early bladder activity in radionuclide cisternography indirect sign of spontaneous intracranial hypotension sequence of lumbar puncture?

Spontaneous intracranial hypotension (SIH) is characterized by severe postural headache and low cerebrospinal fluid (CSF) pressure. Radionuclide cisternography (RC) is of some value in diagnosing CSF leakage causing SIH. However, the sensitivity of RC is too low to demonstrate the site of leakage. In these cases, the early appearance of the radioactivity in the urinary bladder has also been used as an indirect finding in the diagnosis of SIH. The aim of this study was to evaluate the diagnostic reliability of early urinary bladder activity as an indirect sign of SIH. We investigated early bladder activity in 21 patients with suspicion of normal pressure hydrocephalus. Of the 21 subjects, 13 (62%) showed early bladder activity. We demonstrated that early bladder activity is observed in patients without CSF leakage such as normal pressure hydrocephalus. Therefore, this indirect finding of RC is not a reliable finding in diagnosing SIH

Regional ventilation/perfusion mismatch pattern in patient with Swyer James (MacLeod's) syndrome

Swyer James (McLeod's) syndrome (SJMS) is an uncommon disease, which occurs as a result of childhood bronchiolitis obliterans. Patients may not be diagnosed until later in their life. A 46-year-old man underwent ventilation/perfusion scintigraphy for acute onset of dyspnea. The scan showed markedly diminished ventilation and perfusion unilaterally on the right middle and inferior lobes. However, mismatched ventilation-perfusion pattern was shown on the upper right lobe, which was consistent with pulmonary embolism. Unilaterally matched ventilation/perfusion defect can see in SJMS in lung scintigraphy; however, when pulmoner embolism may accompany, scintigraphy should be carefully examined

Thyroid uptake test with portable device (COTI) after I-131 tracer administration: proof of concept

COTI (collar therapy indicator) has been recently introduced for the detection of gamma rays with emphasis on thyroid investigations. The aim of this study was to test the feasibility of a prototype version of COTI including activity detectors with low sensitivity in performing thyroid uptake measurements for a large group of patients. Consequently, thyroid uptake tests were carried out for a total of 89 patients (22 males and 67 females; age: 44 +/- 13 years) with thyroid cancer (n = 74), hyperthyroidism (n = 16) at 2 and 24 h after administration of 0.44-2 MBq of I-131. Eight individuals among the thyroid cancer patients were monitored up to 96 h after administration. The COTI device was equipped with two CsI (Tl) detectors, known as LoHi type, sensitive to activity ranges from 0.02 to 30 MBq of I-131. The uptake values from COTI were compared with those measured with a standard probe. It was found that the mean uptake of thyroid activity in thyroid cancer patients was 2.1 +/- 1.3% at 2 h when measured with the standard probe, while it was 2.2 +/- 1.2% when measured with COTI. In addition, the average uptake at 24 h after administration was 2.5 +/- 3.2% and 3.2 +/- 3.8% measured with COTI and the standard probe, respectively. A strong correlation was found at 24 h between the results obtained with COTI and the standard probe, while a weaker correlation was seen at 2 h. Overall, there was no significant difference between the results obtained with the standard probe and those obtained with COTI at both 2 and 24 h (P-value >= 0.05). Besides, 85% of the uptake values measured with COTI were less than those measured with the standard probe at the 24 h after administration. The average uptake value was 0.9 +/- 0.8% after 96 h by COTI, and 1.4 +/- 1.3% by the standard probe. Pertaining to the hyperthyroidism patients, COTI showed mean uptake values of 20 +/- 16% and 23 +/- 18% at 2 and 24 h, respectively. In contrast, the standard probe suggested higher mean uptake values of 26 +/- 18% and 30 +/- 22%, respectively. It is concluded that the prototype of COTI used in the present study has been proved to be a feasible and promising tool in thyroid investigations. It is noted, however, that the next COTI generation should include detectors equipped with collimator and energy discrimination

A Case with Non-Small Cell Cancer in the Left Lung Diagnosed Following Observation of Bilateral Diffuse Lung Uptake of Tc-99m-MDP on Bone Scintigraphy

Extraskeletal accumulation of Technetium-99m methylene diphosphonate (Tc-99m-MDP) can be seen in bone scintigraphy both in benign and malignant lesions. In malignant lesions, this phenomenon is usually associated with microscopic calcifications due to the abnormal calcium metabolism, and occurs most frequently in the lungs. In this case report, we present a patient with a non-small lung cancer diagnosed following observation of incidental bilateral lung MDP accumulation in bone scintigraphy. Therefore, the tracer distribution in the soft tissues needs to be carefully examined on bone scans and any unexpected visible soft tissue activity should be stated on the scintigraphy report