Clinical Neurology and Neurosurgery 116 (2014) 41–45 Contents lists available at ScienceDirect Clinical Neurology and Neurosurgery jou rn al h om epage: www.elsevier.com/locate/clineuro Correlation of diffusion tensor, dynamic susceptibility contrast MRI and 99m Tc-Tetrofosmin brain SPECT with tumour grade and Ki-67 immunohistochemistry in glioma George A. Alexiou a,∗ , Anastasia Zikou b , Spyridon Tsiouris c , Anna Goussia d , Paraskevi Kosta b , Athanasios Papadopoulos c , Spyridon Voulgaris a , Athanasios P. Kyritsis e , Andreas D. Fotopoulos c , Maria I. Argyropoulou b a Department of Neurosurgery, University Hospital of Ioannina, Ioannina, Greece b Department of Radiology, University Hospital of Ioannina, Ioannina, Greece c Department of Nuclear Medicine, University Hospital of Ioannina, Ioannina, Greece d Department of Pathology, University Hospital of Ioannina, Ioannina, Greece e Department of Neurology, University Hospital of Ioannina, Ioannina, Greece a r t i c l e i n f o Article history: Received 30 May 2013 Received in revised form 3 August 2013 Accepted 9 November 2013 Available online 16 November 2013 Keywords: SPECT 99m Tc-Tetrofosmin Diffusion tensor imaging Perfusion imaging Glioma a b s t r a c t Objective: Assessment of the grade and type of glioma is of paramount importance for prognosis. Tumour proliferative potentials may provide additional information on the behaviour of the tumour, its response to treatment and prognosis. The purpose of this study was to investigate the correlation between diffusion tensor imaging (DTI), dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) and 99m Tc- Tetrofosmin brain single-photon emission computed tomography (SPECT), and the tumour grade and Ki-67 labelling index in newly diagnosed gliomas. Methods: Study was made of patients with suspected glioma on brain MRI between December 2010 and January 2012, by DTI, DSC MRI and 99m Tc-Tetrofosmin brain SPECT. The proliferative activity of each tumour was measured by deriving the Ki-67 proliferation index from immunohistochemical staining of tumour specimens. Results: Glioma was newly diagnosed in 25 patients (17 men, 8 women, aged 19–79 years, median 55 years). The Ki-67 index ranged from 1% to 80% (mean 19.4%). On evaluation of the relationship between the 99m Tc-Tetrofosmin tumour uptake by gliomas was found to be significantly correlated with cellular proliferation (rho = 0.924, p < 0.0001). Regarding DTI, significant negative correlation was demonstrated between the apparent diffusion coefficient (ADC) ratio and the Ki-67 index (rho = -0.545, p = 0.0087). Significant correlation was also observed between the fractional anisotropy (FA) ratio and the Ki-67 index (rho = 0.489, p = 0.02). Strong correlation was found between relative cerebral blood volume (rCBV) and Ki-67 index (rho = 0.853, p < 0.0001), and between the 99m Tc-Tetrofosmin lesion-to-normal (L/N) uptake ratio and rCBV (rho = 0.808, p ≤ 0.0001). Significant negative correlation was demonstrated between the 99m Tc-Tetrofosmin L/N ratio and ADC ratio (rho = -0.513, p = 0.014). These imaging techniques were able to distinguish between low-grade and high-grade gliomas. Conclusions: Findings on DSC MRI and brain SPECT with 99m Tc-Tetrofosmin metrics were more closely correlated with glioma cellular proliferation. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Glioma is the most common type of malignant brain tumour. Glioma grading and typing are crucial for prognosis, but patients with tumours of the same histopathological characterization and ∗ Corresponding author at: Aetideon 52, Holargos, 11561 Attiki, Greece. Tel.: +30 210 6526507/6948 525134. E-mail addresses: alexiougrg@yahoo.gr, alexiougr@gmail.com (G.A. Alexiou). receiving similar treatment may display diverse outcome because of differences in the proliferative potential of the disease [1]. Assessment of tumour proliferation has therefore been suggested as an important additional predictor of tumour behaviour [1]. In addition, identification of the tumour “hot spot” is important for biopsy guidance. Various methods have been proposed for the esti- mation of proliferation in tissue samples, but these require tissue sampling via stereotactic biopsy or craniotomy [2]. The validation of a non-invasive method of assessment of tumour proliferation potential would therefore be of obvious significance. 0303-8467/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.clineuro.2013.11.003