Diffusion restriction associated with bevacizumab treatment in recurrent glial tumors, evaluation of survival with ADC measurement analysis.

OBJECTIVE: Recurrent glial tumors treated with bevacizumab often develop diffusion restriction. In this study, we investigated the diffusion restriction pattern after bevacizumab treatment along with the relationship between apparent diffusion coefficient (ADC) values of regions with diffusion restriction and survival period as there are conflicting results on this relationship. PATIENTS AND METHODS: We retrospectively identified 24 patients treated with bevacizumab for recurrent glial tumor who had low ADC values after the onset of the treatment. Magnetic resonance imaging (MRI) findings were analyzed for the presence of restricted diffusion, time to onset, location, duration of restriction, and persistence of restriction after cessation of bevacizumab treatment. A retrospective study was performed to investigate the relationship between ADC values obtained at first post-bevacizumab scan and survival periods. RESULTS: Diffusion restriction appeared 2 to 6 months after the onset of bevacizumab therapy and persisted up to 24 months while on bevacizumab. The restricted diffusion persisted up to 6 months after cessation of bevacizumab. Our results showed that there is a negative correlation between ADC values and progression free survival as well as overall survival. Patients having diffusion restriction areas with lower ADC values after the initiation of bevacizumab treatment, are found to have increased overall and progression free survival (p<0.05). CONCLUSIONS: In patients with recurrent glial tumor treated with bevacizumab, diffusion restriction can be observed and the ADC values obtained from these areas at first post-bevacizumab MRI scan correlate with progression free and overall survival with the worst survival seen in patients with higher ADC values which therefore can be considered as an imaging marker that can predict the prognosis.

Renal impairment and coronary collaterals in patients with acute coronary syndrome.

OBJECTIVE: We aimed to elucidate the relationship between mild-to-moderate renal impairment and the development of coronary collateral vessels (CCV) in patients with acute coronary syndrome (ACS). METHODS: We enrolled 461 patients with ACS who underwent coronary angiography for the first time. The development of CCV was assessed with the Rentrop score. Kidney function was classified according to the estimated glomerular filtration rate (eGFR). The Gensini score was used to show the extent of atherosclerosis. RESULTS: The mean eGFR value was 89.9 ± 24.3 U/l for patients with no development of collaterals and 82.7 ± 20.5 for patients who had CCV. The mean age was 59 ± 11 years and 349 patients (75.7 %) were male. Rentrop classifications 1-2-3 (presence of CCV) were determined in 222 (48.1 %) patients. The presence of CCV was significantly associated with low levels of eGFR (p = 0.001), increased serum creatinine levels (p = 0.034), high levels of serum albumin (0.036), and the Gensini score (p < 0.001). Multivariate analysis showed that the Gensini score was an independent predictor of the presence of CCV (OR = 1.090, 95 % CI: 1.032-1.151, p = 0.002). CONCLUSION: We suggest that the association between mild-to-moderate renal impairment and the presence of CCV may be explained by increased myocardial ischemia and severe CAD.