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OBJECTIVE: To evaluate dose differences predicted between using Anisotropic Analytical Algorithm (AAA) and Acuros XB (AXB) in patients diagnosed with locally advanced non-small cell lung cancer (NSCLC) treated with intensity modulated radiation therapy (IMRT). METHODS: A phantom study was done to evaluate the dose prediction accuracy of AXB and AAA beyond low-density medium by comparing the calculated measurement results. Thirty-two advanced NSCLC patients were subjected to IMRT. The dose regimen was 60 Gy over 30 fractions. Effects on planning target volume (PTV) and organ-at-risk (OAR) were evaluated. Clinically acceptable treatment plans with AAA were re-calculated using AXB algorithms with two modes Dw and Dm at the same beam arrangements and multileaf collimator leaf settings as with AAA. RESULTS: Using AXB yielded better agreement with the measurements and the average dose difference for all points was about 0.5%. Conversely, using AAA showed a larger disagreement with measured values and the average difference was up to 5.9%. The maximum relative difference was between AXB_Dm and AAA for PTV dose (D98 %). The percentage dose differences of plans calculated by AAA, AXB_Dw and AAA, AXB_Dm revealed that AAA overestimated the dose than AXB. Regarding OAR, results showed significant difference for lungs-PTV. CONCLUSIONS: AXB algorithm yields more accurate dose prediction than AAA in heterogeneous medium. Differences in dose distribution are observed when plans re-calculated with AXB indicating that AAA apparently overestimates dose, particularly the PTV dose. Thus, AXB algorithm should be used in preference to AAA for cases in which PTVs are involved with tissues of highly different densities, such as lung.

Background:The control of schistosomiasis in Egypt was associated with changes in the prevalence and histopathology of urinary bladder cancer. Aim: To investigate the histological pattern among patients treated for bladder cancer at our institution over a 5-year period. Methods: This retrospective study was conducted by reviewing the medical records of 632 patients treated for urinary bladder cancer at the departments of Urology and Clinical Oncology, Al Azhar Faculty of Medicine, between January 2011 and December 2015. Results: The study included 632 patients. Their age ranged from 27-87 years old with a median of 62 years. Male to female ratio was about 6:1. Fifty-nine percent of the patients had Non-Muscle Invasive Bladder Cancer (NMIBC) versus 41% had Muscle Invasive Bladder Cancer (MIBC). Patients with history of schistosomiasis were 46.5%; besides, 67.9% of the patients were smokers. Transitional Cell Carcinoma (TCC) was the predominant histological type (87.5%), followed by Squamous Cell Carcinoma (SCC) 9.1%, mixed SCC and TCC (2.8%), and other subtypes 0.6%. Conclusion: Our study confirms that the histopathological pattern of urinary bladder cancer in Egypt is still changing. Over the last decades, the incidence of bladder SCC is declining and bladder TCC is rising. Yet the incidence of bladder SCC is the lowest compared to previous reports.

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