Background: Cell-free DNA is extracellular nucleic acids found in cell-free plasma/ serum of humans. Circulating extracellular DNA can be found in healthy persons, persons with non-malignant diseases, as well as persons with various malignancies. Given the recent approval of a liquid biopsy, the use of circulating tumor DNA as a novel and non-invasive test for the diagnosis and surveillance of cancer is a rapidly growing area of interest Methods:study was carried out in Menoufia University hospital in the period from May 2015 to December 2015. It was conducted on 80 individuals classified into: Group I: included 40 colorectal cancer (CRC) patients Group II: included 20 patients with colorectal benign diseases. Group III: included 20 healthy controls. Laboratory investigations including detection of quantitative analysis of circulating cell free DNA (ccf-DNA) through detection of short (115bp) DNA fragments in serum by real time quantitative PCR by amplifying the ALU repeats (ALU-qPCR) and CA19 9 serum level by ELISA. Results: There was significant statistical difference in serum level of ALU 115 between group I (1123.86356.3) and both of group II (432.26147.8) and III (3176105) both (p ¼ 0.001), where there was non-significant statistical difference in serum levels ALU 115 between group II & III (p ¼ 0.180). There was significant statistical difference in serum level of CA19-9 between group I (42.4692.3) and both of group II (10.565.87) (p ¼ 0.032) and III ( 9.7465.62) (p ¼ 0.013), where there was non-significant statistical difference in serum levels of CA19-9 between group II & III (p ¼ 0.684). The diagnostic accuracy for distinguishing primary CRC patients from normal control by ALU 115 is (85%), with sensitivity (83%), specificity (90%), positive predictive value (96%) and negative predictive value (64%) at cut off point of 426 ng/ml. The diagnostic accuracy by CA19-9 is (59%), with sensitivity (60%), specificity (55%), positive predictive value (80%) and negative predictive value (31%) at cut off point of 8.45 U/ml. combined detection of ALU115 and CA19-9 improved the sensitivity to (88%). There was a significant positive correlations between ALU 115 serum level and tumor grade (p ¼ 0.024), also between CA19-9 and primary tumor stage and presence of metastases (p ¼ 0.012) and (p ¼ 0.044) Conclusions: It was concluded that serum DNA concentrations may be valuable in early diagnosis and monitoring of colorectal cancer patients Legal entity responsible for the study: Menoufia University Disclosure: All authors have declared no conflicts of interest. 77 DNA and RNA analysis of intratumour heterogeneity in metastatic clear cell renal cell carcinoma

Background: The PI3K/AKT/mTOR pathway is frequently activaed across many cancers. AKT1 is a subfamily of serine/threonine protein kinases, affecting cell survival, proliferation and invasion. The prior reports from Western country have shown AKT1 mutation in 3-6% of breast cancer and in 2-3% of endometrial cancer. However, the clinico-pathological features of AKT1 E17K mutation in Asian female cancers is unclear. In this study, we examined breast cancer samples and endometrial cancer samples for mutation in AKT1 hotspot at our institution. Methods: For patients with breast cancer and endometrial cancer, we retrospectively analyzed tissue samples preserved between January 2008 and June 2015 in a biobank at national cancer center hospital. We extracted DNA and determined AKT1 mutation with PNA-LNA clamp methods. Kaplan-Meier analysis was performed to analyze relapse-free survival (RFS) after surgery and overall survival (OS) for breast cancer patient. Results: A total of 469 patients were analyzed. Three hundred and twenty-nine patients were breast and 140 were endometrial cancer. The median age was 52 (range 22-90). In breast cancer patients, 305 patients were initially stage I to III, and thirty-two patients were initially Stage IV. The number of tumor subtype was hormone receptor (HR) positive and HER2 negative tumor; 248 (74%), HR positive and HER2 positive tumor; 44 (13%), HR negative and HER2 positive tumor; 28 (8%), and Triple negative tumor; 17 (5%), respectively. We detected AKT1 mutation in 24 patients (7.3%) of breast-cancer patients and 7 patients (5.0%) of endometrial-carcinoma patients. In breast cancer patients, there were 176 relapses and 32 deaths. Median RFS was 79 months in patients with AKT1 wild type and 75 months in patients with AKT1 mutation (p-value:0.77). Conclusions: We detected AKT1 mutation in 31 patients (6.6%) of 469 breast and endometrial cancer. RFS in breast cancer patients is not significantly different by AKT1 mutation status. Legal entity responsible for the study: National Cancer Center Hospital Funding: None Disclosure: All authors have declared no conflicts of interest.47P Study of tumor immune contexture in patients with squamous carcinomas of head and neck in the Indian population -A pilot study

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