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Objectives: Axial flap surgery is associated with numerous complications. The purpose of this study is to determine the frequency of these complications, and identify possible factors contributory to their occurrence.   Methods: Study design:       Cross-sectional study   Setting:                 Tertiary public university hospital   Subjects:              Records of all patients who underwent axial pedicled flap reconstruction at the otorhinolaryngology ward of our tertiary public university hospital from January 2013 to July 2015 were retrospectively reviewed, and data consisting of age, sex, diagnosis, disease stage, smoking history, alcohol intake, co-morbidities, past operations, pre-operative hemoglobin and albumin, total operative time, total blood loss, location and total area of the surgical defect, and length of hospitalization were tabulated.  All complications were listed. Data were analyzed for any potential trends.   Results: A total of 38 patients underwent axial pedicled flap reconstruction in the study period. Nineteen out of 38 (50%) cases involved complications. The most common complication was infection. Most of the complications occurred in males with history of alcohol intake, advanced cancer stage, significant blood loss, recurrent tumors, low pre-operative hemoglobin and albumin levels, and a large area of surgical defect.   Conclusions: The complication rate for axial flap surgery in our series was significant at 50%. Potential risk factors identified were male gender, advanced cancer stage, tumor recurrence, alcohol intake, low pre-operative hemoglobin and albumin levels, significant blood loss, longer operative time, and a larger surgical defect.   Keywords: surgical flaps, myocutaneous flap, axial flap, complications, risk factors  

6063 Background: NPC is highly curable in early stages but 70% of NPC patients are diagnosed with advanced disease due to lack of effective screening. Genetic and epigenetic alterations involved in the pathogenesis of NPC are known. The higher order chromosomal structures reflecting aberrant transcriptional states of these genes can be measured via techniques such as chromosome conformation capture. Detection of these changes in peripheral blood may provide an accurate test for the early cancer detection. Methods: Blood samples have been collected from 84 patients with histologically confirmed NPC and 100 matched controls. Samples from 45 NPC patients and 68 controls have been analyzed. Fourteen genes known to be dysregulated in NPC were investigated. Potential higher order juxtaposition sites in the candidate genes were predicted using pattern recognition software. PCR primer sets were designed around the chosen sites to screen potential markers. Twenty-two markers showing predictability between NPC and control samples were analysed for optimal reproducibility using alternative primer sets. The optimal sets of markers were then tested amongst the complete set of samples. The dataset was processed by re-sampling using the synthetic minority oversampling technique. The overall sample was split into two groups (66% training set and 34% test set) in the classification. Results: Sixteen markers from 7 candidate genes were found to be optimal in differentiating between NPC and control samples in the first 103 samples. Using the multilayer perceptron (MLP) classification, the following results were obtained: Sensitivity 88.9%, 95% CI (79.2% - 98.6%); Specificity 72.7%, 95% CI (58.9% - 86.5%); PPV 72.7%, 95% CI (58.9% - 86.5%); NPV 88.9%, 95% CI (79.2% - 98.6%). The accuracy of the test was similar in detection of stage I and II NPC versus that of stage III or IV NPC. Conclusions: Using a PCR-based method to detect alterations in the cancer epigenome, the feasibility of developing a blood test of potential utility in early diagnosis of NPC was demonstrated. Analysis of larger numbers of patient samples and optimization of markers are ongoing. The performance characteristics of the test in the total population of 184 samples will be presented.