Omar Mahmoud
Rutgers University
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Featured researches published by Omar Mahmoud.
Radiotherapy and Oncology | 2017
Omar Mahmoud; Ahmet Tunceroglu; Ravi J. Chokshi; Joseph Benevenia; Kathleen S. Beebe; Francis Patterson; Thomas F. DeLaney
PURPOSE Intergroup 9514 reported promising outcomes with neoadjuvant chemoradiotherapy for large extremity/trunk soft tissue sarcoma (ESTS). One decade later, optimum integration of chemotherapy and radiotherapy into the perioperative management of ESTS remains to be defined. METHODS The National Cancer Data Base was used to identify 3422 patients who underwent resection for large (>8cm) high-grade STS between 2004 and 2013. Chi-square analysis was used to evaluate distribution of patient and tumor related factors within treatment groups while multivariate analyses were used to determine the impact of these factors on patient outcome. The Kaplan Meier method and Cox proportional hazards model were utilized to evaluate overall survival according to treatment regimen, with a secondary analysis based on propensity score matching to control for prescription bias and potential confounders imbalance. RESULTS Hazard ratio for death was reduced by 35% with radiotherapy and 24% with chemotherapy, compared to surgery alone. Combination therapy incorporating both modalities improved 5-yr survival (62.1%) compared to either treatment alone (51.4%). The sequencing of chemotherapy and radiotherapy or whether they were delivered as adjuvant vs. as neoadjuvant therapy did not affect their efficacy. Age>50years, tumor size>11cm, and tumor location on the trunk/pelvis were poor prognostic factors. CONCLUSION Our analysis suggests that adjunctive modalities are both critical in the treatment of large high-grade ESTS, improving survival when used individually and demonstrating synergy in combination, regardless of sequencing relative to each other or relative to surgery; thus providing a framework for future randomized trials.
Breast Journal | 2015
Bruce G. Haffty; Omar Mahmoud
Breast cancer regional node management has witnessed many changes over the last decade. Advances in surgical techniques establishing sentinel lymph node biopsy as an alternative to axillary dissection, use of microarray technology for subtyping breast cancer to guide systemic therapy selection, and the expansion of the systemic therapy armamentarium including targeted agents have contributed to changing our strategy from one size fits all to a more tailored approach. There have also been recent landmark studies reported that significantly impact clinical practice in the regional nodal management of breast cancer. As the molecular era of personalized medicine is approaching, we hereby revisit the rational, benefit, and controversies of regional nodal irradiation in the light of the most recent publications.
Annals of Translational Medicine | 2015
Sarah S. Kılıç; Bernadette Cracchiolo; Molly Gabel; Bruce G. Haffty; Omar Mahmoud
BACKGROUND Radiotherapy (RT) plays an integral role in the combined-modality management of cervical cancer. Various molecular mechanisms have been implicated in the adaptive cellular response to RT. Identification of these molecular processes may permit the prediction of treatment outcome and enhanced radiation-induced cancer cell killing through tailoring of the management approach, and/or the employment of selective inhibitors of these pathways. METHODS PubMed was searched for studies presenting biomarkers of cervical cancer radioresistance validated in patient studies or in laboratory experimentation. RESULTS Several biomarkers of cervical cancer radioresistance are validated by patient survival or recurrence data. These biomarkers fall into categories of biological function including hypoxia, cell proliferation, cell-cell adhesion, and evasion of apoptosis. Additional radioresistance biomarkers have been identified in exploratory experiments. CONCLUSIONS Biomarkers of radioresistance in cervical cancer may allow molecular profiling of individual tumors, leading to tailored therapies and better prognostication and prediction of outcomes.
American Journal of Clinical Oncology | 2016
Omar Mahmoud; Austin Dosch; Deukwoo Kwon; John D. Pitcher; Sheila A. Conway; Pasquale Benedetto; Gustavo Fernandez; Jonathan C. Trent; H. Thomas Temple; Aaron H. Wolfson
Purpose:The perioperative management of primary extremity soft-tissue sarcomas (ESTS) is multidisciplinary including radiation therapy and chemotherapy (CT). The interplay between these modalities and the relative importance of each remain unclear. Our study aims to determine the relative impact of CT and radiotherapy on the outcome of ESTS patients treated with limb-sparing surgery. Materials and Methods:A retrospective review of ESTS registry yielded 97 patients who received neoadjuvant chemotherapy (NCT) and/or adjuvant CT with or without external-beam radiation therapy (EBRT) from January 1, 1999 through December 31, 2009. The cohort comprised 56 males and 41 females whose age at surgery ranged from 17 to 83 years (median, 56 y). Tumor characteristics included the following: 73 lower ESTS; 70 grade 3 lesions; 63 American Joint Committee on Cancer stage III tumors; and 27 lesions with positive microscopic margins. The following outcome parameters were evaluated for the patients’ subgroups: overall survival (OS), locoregional control (LRC), and disease-free survival (DFS). Results:EBRT was delivered postoperatively to 81 patients and 49 received CT. Median EBRT dose was 63 Gy (range, 50 to 72 Gy). At median follow-up of 54.6 months, the 5-year OS, LRC, DFS was 68.9%, 87.1%, 66.5%, respectively. On multivariate analysis, positive surgical margins negatively impacted LRC, DFS, and OS (hazard ratio [HR]=10.43, P=0.004), (HR=2.37, P=0.03), (HR=2.26, P=0.038), respectively. EBRT use improved LRC (HR=0.24, P=0.018) and DFS (HR=0.36, P=0.021). The impact of EBRT on DFS was retained (HR=0.28, P=0.006) in the high-grade ESTS subgroup who received CT. The 5-year local failure rate was 6.5%, 28.6%, and 22.2% (P=0.019) for patient receiving NCT, adjuvant chemotherapy, and no CT, respectively. Conclusion:Our data support the use of NCT followed by limb-sparing surgery and adjuvant EBRT in ESTS for local failure reduction with a trend toward improved DFS.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2018
Omar Mahmoud; Kim Sung; Francisco Civantos; Giovanna Thomas; Michael Samuels
The emergence of transoral robotic surgery (TORS) ignited the debate between surgical and nonsurgical strategies on oropharyngeal squamous cell carcinoma (SCC) management; a question further complicated by human papillomavirus (HPV). We evaluated the survival by treatment strategy independently in HPV‐related and HPV‐nonrelated oropharyngeal SCC.
International Forum of Allergy & Rhinology | 2017
Suat Kılıç; Sarah S. Kılıç; Emilie S. Kim; Soly Baredes; Omar Mahmoud; Stacey T. Gray; Jean Anderson Eloy
The role of human papillomavirus (HPV) in sinonasal squamous cell carcinoma (SNSCC) is not well understood.
Annals of Translational Medicine | 2015
Omar Mahmoud; Bruce G. Haffty
The last decade witnessed the gradual adoption of sentinel lymph node biopsy (SLNB) to stage the axilla of breast cancer (BC) patients presenting with clinically negative lymph nodes; aiming to minimize the complications of the formal (gold standard) axillary lymph node dissection (ALND). Although abandoning ALND in pathologically negative sentinel node (SN) became the current standard of care, a similar consensus remains lacking in patients with positive SN.
International Forum of Allergy & Rhinology | 2018
Suat Kılıç; Sarah S. Kılıç; Soly Baredes; Richard Chan Woo Park; Omar Mahmoud; Jeffrey D. Suh; Stacey T. Gray; Jean Anderson Eloy
The use of endoscopic resection as an alternative to open surgery for sinonasal malignancies has increased in the past 20 years.
Practical radiation oncology | 2018
Stephen Sozio; Zorimar Rivera-Núñez; Omar Mahmoud; Sung Kim
PURPOSE When treating head and neck squamous cell carcinoma (HNSCC) with intensity modulated radiation therapy (IMRT), it is common to use several dose levels for a lymph node positive neck: full dose (66-70 Gy) to gross cancer, intermediate dose (59-63 Gy) to higher risk neck regions, and standard dose (50-54 Gy) to lower risk neck regions. There is no consensus regarding how much of the neck should receive intermediate versus standard dose, however. METHODS AND MATERIALS HNSCC patients treated with IMRT were identified from 2 academic medical centers between 2004 and 2016. Intermediate dose was restricted to a region of the neck 2 cm above and below the most superior and inferior involved lymph nodes; standard dose was delivered to more distal neck regions. Descriptive statistics were calculated for demographics and clinical characteristics as well as proportions for failures 2 years after treatment. Failure outside the intermediate dose region was determined by calculating confidence intervals from a modification of the Poisson distribution. RESULTS Of the 57 necks included in this study, 17.5% experienced disease recurrence in the neck within 2 years of completing treatment. All failures were within the 2-cm margin above or below the most superior and inferior involved nodes; there were no failures outside this 2-cm margin (95% confidence interval, 0-7.7). CONCLUSIONS The results of this study support the feasibility of treating only the neck adjacent to gross neck disease to an intermediate dose, and treating the remainder of the neck to a lower, standard dose. Although these results are encouraging, additional study of this treatment paradigm is warranted.
Otolaryngology-Head and Neck Surgery | 2018
Suat Kılıç; Sarah S. Kılıç; Kajal P. Shah; Jean Anderson Eloy; Soly Baredes; Omar Mahmoud; Richard Chan Woo Park
Objective To determine the frequency, associated factors, and prognosis of clinicopathologic stage discrepancy in oropharyngeal squamous cell carcinoma (OPSCC). Study Design Retrospective study using a national database. Setting National Cancer Database. Subjects and Methods Cases of OPSCC diagnosed between January 1, 2004, and December 31, 2013, with full clinical and pathologic staging information available were identified. Demographic, clinicopathologic, and treatment variables associated with overall stage discrepancy were identified by multivariate logistic regression analysis. Results In total, 7731 cases of OPSCC were identified. Overall stage discrepancy was present in 30.2% of cases (21.9% upstaging, 8.2% downstaging). A total of 13.1% of cases were T-upstaged, and 10.5% of cases were T-downstaged; 22.9% of cases were N-upstaged, and 8.6% of cases were N-downstaged. Upstaging by overall stage was associated with a high Charlson-Deyo score, high tumor grade, number of lymph nodes examined, and increasing tumor size. No factors were positively associated with downstaging. High tumor grade was negatively associated with downstaging. For stage II, III, and IVA tumors, upstaging was associated with poorer OS. Conclusion Clinicopathologic stage discrepancy is common in OPSCC and is likely attributable to insensitive clinical staging techniques as well as to intrinsic tumor biologic properties. Upstaging is associated with poorer prognosis, which is likely due to advancement of disease.