Η συμβολή της αξονικής τομογραφίας εκπομπής μονήρους φωτονίου (SPECT) στη διάκριση νεοπλασματικής από μη νεοπλασματικής αιτιολογίας ενδοεγκεφαλικής αιμορραγίας
Authors: Αλ-Μπουχαραλή Τζιχάντ 
Published: September 2021

The discrimination of neoplasmatic from non-neoplastic intra-cerebral hematoma is a major challenge for clinicians and investigators, as various types of neoplasms can be covered behind an intraparenchymal cerebral hemorrhage (ICH) and some non-neoplastic hemorrhage lesions can mimic neoplasms in typical neurological / radiographic imaging. This differential diagnosis, particularly in the acute phase, has significant clinical significance for proper management and effective treatment of patients. In the past, some studies have been proposed aimed at differentiating ICH associated with neoplasms based on neuro-radiological and nuclear imaging characteristics. However, the effectiveness of these imaging methodologies was, in most cases, under discussion. In clinical practice, the differential diagnosis between neoplastic and non-neoplastic ICH is often based on ongoing monitoring of the evolutionary pathway of pathogenesis over time, delaying the provision of the appropriate treatment planning for effective treatment ofpatients. The 99mTc-Tetrofosmin (99mTc-TF) radiopharmaceutical has been used as a SPECT imaging agent in various cases, except for its common indication that is the myocardial perfusionscintigraphy. In particular, 99mTc-TF has been used in the detection of various neoplasms mainly in the breast and brain regions. In the latter case, the Nuclear Medicine Laboratory of the University Hospital of Ioannina appears a great clinical experience with a large number of publications for 99mTc-TF use in the development of gliomas, astrocytomas, glioblastomas, intracranial meningiomas and various brain metastases. Attempts to visualize such tumors have also been made with the use of other radiopharmaceuticals such as 99mTcMethoxyisobutyltinnitrile (99mTc-MIBI) and relatively earlier radioactive 201T1 with reduced performance. A total of 70 patients (41 men, 29 women, median 59.3 ± 15.1 years) were enrolled to evaluate the ability of 99mTc-TF brain SPECT to distinguish intracerebral hemorrhage, neoplastic from non-neoplastic etiology. The set of subjects consists of two subgroups. The first group, consisting of 50 patients (31 men, 19 women, median 58.5 ± 16.5 years), diagnosed with intracerebral hemorrhage without tumor disease and the second group of 20 patients (10 males , 10 women, median 61.4 ± 9.9 years) diagnosed with neoplastic disease in the form of glioma. Patients depending on the clinical condition, age, location and magnitude of the damage and coexisting conditions were treated conservatively or surgically. All patients underwent MRI and SPECT with 99mTc-TF brain scans within the first 6 days of diagnosis of ICH. Patients who were conservatively treated were prospectively monitored to determine the cause of ICH. The diagnosis was based on clinical and imaging monitoring over a 2-year mean interval which was considered sufficient to identify a possible neoplastic underlying cause based on international literature and since most neoplasms usually have rapid progressionwithin the restricted intracranial space. Initially, during the process of identifying and evaluating the pathogenesis, the MRI or CT findings are compared and identified with SPECT imaging. Then, after the outline is drawn, the brightness ratio of the pathogenic area (hemorrhage and / or neoplasm) to its background (Lesion to Normal, L / N) was calculated. In the case of ICH, the average luminance value was found to be 1.74 with a range from 1.0-4.04 (CV: 0.359). In the case of gliomas, theaverage luminance value was found to be 8.47 with a range of 2.7 - 15.6 (CV: 0.511). Different models were then used to find the optimal separation threshold for the two different haemorrhage groups. Thus, the Linear Separation Approach as well as the use of the non-parametric Mann-Whitney method were tested to overcome the regularity of patient data. In addition, a receiver operating characteristic (ROC) analysis was performed to calculate the optimal threshold value in the overall performance of the characterization system converging to the L / N ratio = 2.88 as the most reliable threshold for discrimination of neoplastic from non-neoplastic ICH episodes. Statistical analysis confirmed that tumor neoplastic haemorrhage had a statistically significantly higher uptake of radiopharmaceutical than non-neoplastic etiology ICH. In conclusion, SPECT with 99mTc-TF radiopharmaceutical, could provide a significant contribution to the clinician in differential diagnosis of neoplastic and non-neoplastic haemorrhage. However, significant research could be carried out, as a continuation of this study, on the depiction of the evolution of the computed luminosity ratio of the pathogenesis over time, both in the short and the long term, as well as the accurate and timely separation of the specific type and the origin of each neoplasia.