2012 Scholarship Winners
Peripancreatic Soft Tissue Involvement as a Novel Independent Predictor of Outcome for Patients with Resected Pancreatic Malignancy
Alireza Hamidian Jahromi, MD
Clinical Research Fellow, Shreveport, LA
Gazi B. Zibari, MD, FACS, FICS; Elnaz Jafarimehr, MD; Quyen Chu, MD, FACS; Gregory P. Wellman, MD, FACR; Runhua Shi, MD, PhD; Hosein Shokouh-Amiri, MD, FACS, FICS.
Research Location: Department of Surgery, Louisiana State University Health Sciences Center, Shreveport, LA.
Purpose: The impact of an involved peripancreatic soft tissue (PST), irrespective of resection margin status, following a pancreatectomy is not known. We determine the impact of such involvement on a cohort of patients with pancreatic malignancies.
Methods: Data on 117 patients who had surgery for pancreatic malignancies between 2/1/1998 and 5/31/2010 were retrospectively analyzed. Patients were categorized into 3 groups: Group 1=R1 resection (N=33), Group 2=R0 with involved PST (N=22), and Group 3=R0 with uninvolved PST (N=62). Demographics, operative data, tumor characteristics, complications, and overall survival (OS) were assessed.
Results: 77% of patients had adenocarcinoma and 11.1% had neuroendocrine tumors. The operations performed were: Whipple (N=84), distal pancreatectomy (N=18), and total pancreatectomy (N=8). The grades were: 1(11.3%), 2(50.4%), 3(32.2%), and 4(6.1%). The stages were: 1A(4.3%), 1B(19%), IIA(19%), IIB(42.2%), III(11.2%), and IV(4.3%). Stages IIB-IV had significantly lower median OS than stages I-IIA (p=0.004). Five-year-OS for the entire group was 32.7%. The 5-year-OS for N0 and N (+) was 38.3% and 24.3% (p<0.05) respectively, and R0 and R1 was 37.9% and 19.5% (p<0.05) respectively. Median OS for Groups 1, 2 and 3 were 10.7 months, 12 months, and 37.5 months respectively (p=0.0002). Cox regression analysis demonstrated that age, complications, grade, stage, PST involvement, lymph node and margin statuses were all independent predictors of mortality.
Conclusions: PST involvement independently predicts a poor outcome in patients who had pancreatectomy for malignancy. Survival in patients with PST tumor involvement in the presence of a negative resection margin is similar to those with a positive margin.
Screening in Colorectal Cancer: Are the 'Young' Being Overlooked?
Deepa Taggarshe, MD, MRCS, M Phil
Neelima Rehil, MD, Sonia Sharma BS, Amir Damadi MD, FACS.
Research Location: Providence Hospital and Medical Centers, Southfield, Michigan 48075
Purpose: Colorectal cancer (CRC) screening has improved survival through early detection. Current guidelines recommend colonoscopy from age 50 to 75. But guidelines for early detection in patients<50 are lacking, although there is an increasing incidence.
Our purpose was to assess the trends of CRC in a community-hospital, determining the adequacy of current-screening and identify risk-factors in those <50.
Methods: Cancer registry data was investigated to identify patients with CRC. Patients were divided depending on age at diagnosis:- <50, 50-75 and >75 years. Charts were reviewed of patients <50, with no family-history.
Results: 3599 patients had CRC treated between January 1982-December 2010. Patients aged <50 increased from 6.8 % to 8.5 %, whereas those between 50-70 years decreased from 45.5% to 43.4%(p=0.03).
187 patients were aged <50 at diagnosis. None of these had screening colonoscopy. Mean age at diagnosis was 43 years.
84% were symptomatic. Symptoms included rectal-bleeding (76.5%), abdominal-pain(58%), altered-bowel-pattern(71%), and weight-loss(27%). Asymptomatic patients were evaluated for anemia (58%), positive-Guaiac-test(33%), positive-abdominal-mass(16%) and positive-rectal-mass(25%).
Majority had stage III(40%) or Stage IV(20%) disease. Four patients had synchronous lesions. Comparatively, in age (50-70 years), 28% had Stage III and 21% had Stage IV.
Conclusions: More patients < 50 are being diagnosed with CRC. 60% of these, in this study had advanced cancer at diagnosis, which could have been potentially prevented by screening colonoscopy. The age group 50-70 years, who are currently eligible for screening colonoscopy, had fewer patients with advanced disease probably reflecting an advantage of screening colonoscopy.
Most patients <50 were symptomatic and this highlights the need for pursuing colonoscopy in these, as the symptoms may be indicative of a CRC.
Effects of Intraluminal Chemotherapy on Colorectal Cancer: Study In An Orthotopic Murine Model
Jasneet Singh Bhullar, MD, MS
Amir Damadi MD, FASCRS, Gokulakkrishna Subhas MD, S V S Malladi MD, Jacqueline Tilak BS, Navin Anthony DO, Lee Andrus LVT, BIS, Milessa Decker LVT, Vijay K Mittal MD, FACS
Research Location: Departments of General Surgery, Hematology - Oncology, Patient care research. Providence Hospital & Medical Centers, Southfield, MI
Purpose: Previously, intraluminal chemotherapy was used as an adjunct to surgery to decrease tumor micro metastasis. Theoretically, transanal chemotherapy offers benefits over conventional chemotherapy as it acts directly on the mucosal surface where the tumor transformation takes place. The purpose of our study was to evaluate the effects of transanal chemotherapy in a true orthotopic colorectal cancer murine model for subsequent potential application in humans.
Methods: An intraluminal-mucosal orthotopic colon cancer murine model was designed by doing transanal low dose mucosal coagulation, using a specially designed electrode, 2cm inside the anus. Followed by transanal instillation of LS174T human colon cancer cells(1x10 6) in NOG mice. Control, 5FU, Irinotecan and Oxaliplatin groups had 10 mice each. Treatment groups underwent weight adjusted 3 doses of alternate day transanal drug instillation after intraluminal tumor was confirmed by Coloview-mouse colonoscope.
Results: Control group showed a mean survival of 3.5wks, tumor size of 14Â±4mm with widespread metastasis. 5FU group had an increased mean survival of 12wks, disappearance of primary tumor in 7 mice and mean tumor size of 0Â±3mm with decreased metastasis. The Irinotecan and Oxaliplatin groups showed increased survival of 5wks and 6.5wks with tumor sizes of 5Â±2mm and 3Â±2mm respectively.
Conclusions: Transanal chemotherapy shows promising effects on colonic tumor with considerably decreased primary tumor size and increased survival. This treatment option could be applied to patients with early rectal tumors, colonic dysplasia and syndromes with predisposition for colorectal cancer. This is the first report of effects of transanal chemotherapeutic agents in a true orthotopic colorectal cancer model.
Medical Student Award
Implementing Biomarkers for the Quantification and Resolution of Traumatic Brain Injury in Physical Impact Versus Non-Contact Brain Trauma Animal Models
Mr. Brad Bilowus, BS, Charlottesville, VA
Research Location: University of Virginia, Charlottesville, Virginia
Driven by the increased use of improvised explosive devices on the modern battlefield, Traumatic Brain Injury (TBI) can be unknowingly sustained through blast energy transmission without requiring direct contact injury to the victim. TBI continues to be difficult to assess clinically, as modern imaging techniques are limited in sensitivity, specificity, and availability. This project investigated the potential to utilize a radiolabeled 64Cu-ATSM hypoxia probe to overcome these challenges, and improve current TBI diagnosis and medical treatment ability.
The research study involved controlled cortical impact (CCI) animal injury modeling in an autoradiographical experimental protocol employing serial brain tissue sectioning and phosphor imaging techniques. Image analysis was carried out using specialized software to find the average pixel intensity to background intensity ratio across an experimentally determined set of regional structures within the brain. Regional image intensity ratios corresponded to the degree of injury sustained in experimental animal models.
Combined collected data indicated a consistent hypoxic response to TBI that was concentrated within the hippocampus region of the brain. This response was verified across repeated experiments and through comparison to sham-injury control experiments. Preliminary findings presented in this paper reinforce the goals of this project, and provide an initial demonstration of the ability to characterize TBI using novel molecular biomarker ligands.
By employing a CCI model of TBI, we were able to demonstrate accumulation of 64Cu-ATSM within injured tissues. Collected data provides compelling preliminary evidence for the potential use of 64Cu-ATSM to identify tissue hypoxia following experimental CCI. The current study provides an important first step in validating the utility of neuroimaging biomarkers to efficiently characterize how the brain is altered following TBI.