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Featured researches published by Lia Assumpcao.


Annals of Surgical Oncology | 2007

Simultaneous resections of colorectal cancer and synchronous liver metastases: A multi-institutional analysis

Srinevas K. Reddy; Timothy M. Pawlik; Daria Zorzi; Ana L. Gleisner; Dario Ribero; Lia Assumpcao; Andrew S. Barbas; Eddie K. Abdalla; Michael A. Choti; Jean Nicolas Vauthey; Kirk A. Ludwig; Christopher R. Mantyh; Michael A. Morse; Bryan M. Clary

BackgroundThe safety of simultaneous resections of colorectal cancer and synchronous liver metastases (SCRLM) is not established. This multi-institutional retrospective study compared postoperative outcomes after simultaneous and staged colorectal and hepatic resections.MethodsClinicopathologic data, treatments, and postoperative outcomes from patients who underwent simultaneous or staged colorectal and hepatic resections at three hepatobiliary centers from 1985–2006 were reviewed.Results610 patients underwent simultaneous (n = 135) or staged (n = 475) resections of colorectal cancer and SCRLM. Seventy staged patients underwent colorectal and hepatic resections at the same institution. Simultaneous patients had fewer (median 1 versus 2) and smaller (median 2.5 versus 3.5 cm) metastases and less often underwent major (≥ three segments) hepatectomy (26.7% versus 61.3%, p < 0.05). Combined hospital stay was lower after simultaneous resections (median 8.5 versus 14 days, p < 0.0001). Mortality (1.0% versus 0.5%) and severe morbidity (14.1% versus 12.5%) were similar after simultaneous colorectal resection and minor hepatectomy compared with isolated minor hepatectomy (both p > 0.05). For major hepatectomy, simultaneous colorectal resection increased mortality (8.3% versus 1.4%, p < 0.05) and severe morbidity (36.1% versus 15.1%, p < 0.05). Combined severe morbidity after staged resections was lower compared to simultaneous resections (36.1% versus 17.6%, p = 0.05) for major hepatectomy but similar for minor hepatectomy (14.1% versus 10.5%, p > 0.05). Major hepatectomy independently predicted severe morbidity after simultaneous resections [hazard ratio (HR) = 3.4, p = 0.008].ConclusionsSimultaneous colorectal and minor hepatic resections are safe and should be performed for most patients with SCRLM. Due to increased risk of severe morbidity, caution should be exercised before performing simultaneous colorectal and major hepatic resections.


Annals of Surgery | 2007

Preoperative assessment of hepatocellular carcinoma tumor grade using needle biopsy: Implications for transplant eligibility

Timothy M. Pawlik; Ana L. Gleisner; Robert A. Anders; Lia Assumpcao; Warren R. Maley; Michael A. Choti

Objective:To examine the diagnostic agreement of preoperative needle core biopsy (NCB) grading of hepatocellular carcinoma (HCC) compared with the final surgical pathologic tumor grade. Summary Background Data:Some centers have adopted protocols for selecting patients with HCC for transplantation based on tumor grade as determined by preoperative NCB. The validity of NCB to predict final tumor grade has not been previously assessed. Methods:A total of 211 patients who underwent hepatic resection, open radiofrequency, or transplantation for HCC between 1998 and 2004 were identified. Clinicopathologic, NCB, and surgical data were collected and analyzed using χ2 and κ statistics. Results:A total of 120 (67.4%) of the 178 who underwent resection or transplantation had an NCB. On preoperative NCB, the majority of HCC cases were classified as well-differentiated (n = 35; 37.6%) or moderately differentiated (n = 44; 47.3%), while 14 (15.1%) cases were categorized as poorly differentiated. In contrast, when tumor grading was based on the final surgical specimen, there was a significantly higher proportion of HCC cases graded as poorly differentiated (well-differentiated, n = 34; 36.6%; moderately differentiated, n = 33; 35.5%; poorly differentiated, n = 26; 27.9%) (P < 0.05). The overall percent agreement of NCB and surgical pathology to determine tumor grade was poor (κ = 0.18, P < 0.0001). Whereas final pathologic tumor grade predicted the presence of microscopic vascular invasion (well, 15.7%; moderate; 31.9%, poor; 58.4%; P = 0.001), NCB grade did not (well, 23.7%; moderate, 28.0%; poor, 25.4%; P = 0.65). Conclusions:Selection of candidates for transplantation based on NCB tumor grade may be misleading, as NCB tumor grade often did not correlate with grade or presence of microscopic vascular invasion on final pathology. Clinicomorphologic criteria (tumor size, number) should remain the major determinants of eligibility for transplantation.


Archives of Surgery | 2008

Colorectal Liver Metastases Recurrence and Survival Following Hepatic Resection, Radiofrequency Ablation, and Combined Resection-Radiofrequency Ablation

Ana L. Gleisner; Michael A. Choti; Lia Assumpcao; Hari Nathan; Richard D. Schulick; Timothy M. Pawlik

HYPOTHESIS Although radiofrequency ablation (RFA) is increasingly an accepted option for patients with colorectal liver metastases, patients treated with resection vs RFA may have different tumor biology profiles, which might confound the relationship between choice of liver-directed therapy and outcome. DESIGN Retrospective review of a prospectively collected database. SETTING Major hepatobiliary center. PATIENTS Between January 1, 1999, and August 30, 2006, 258 patients with colorectal liver metastases underwent hepatic resection with or without RFA. MAIN OUTCOME MEASURES Evaluation of outcome following resection alone, combined resection-RFA, and RFA alone using 3 statistical methods (paired-match control, Cox proportional hazards multivariate model, and propensity index) to identify and adjust for potential confounding variables. RESULTS The median number of hepatic lesions was 2, and the median size of the largest lesion was 3.0 cm. One hundred ninety-two patients (74.4%) underwent resection alone, 55 patients (21.3%) underwent resection-RFA, and 11 patients (4.3%) underwent RFA alone. Patients who underwent resection-RFA had significantly increased risk of extrahepatic failure at 1 year vs patients who underwent resection alone or RFA alone (P < .05). On matched control and multivariate analyses, patients who underwent RFA with or without resection had significantly worse disease-free and overall survival than patients who underwent resection alone. Propensity score methods revealed that the aggregate distribution of clinical risk factors for resection-RFA was markedly different from that for resection alone. This suggested a lack of comparability to allow for statistical comparisons in the assessment of causal inferences regarding the efficacy of RFA therapy. CONCLUSION Although results of matched control and multivariate analyses suggested that RFA with or without resection was associated with worse outcome, propensity score methods revealed that the resection-RFA and resection-alone groups were different with regard to baseline tumor and treatment-related factors, making causal inferences about the efficacy of RFA unreliable.


Cancer | 2007

Is resection of periampullary or pancreatic adenocarcinoma with synchronous hepatic metastasis justified

Ana L. Gleisner; Lia Assumpcao; John L. Cameron; Christopher L. Wolfgang; Michael A. Choti; Joseph M. Herman; Richard D. Schulick; Timothy M. Pawlik

To date, no consensus has been reached regarding which primary tumor subtypes are managed appropriately with hepatic metastectomy. Specifically, the role of hepatic resection for metastatic periampullary or pancreatic adenocarcinoma remains controversial.


Archives of Surgery | 2008

Patterns of Recurrence Following Liver Resection for Colorectal Metastases: Effect of Primary Rectal Tumor Site

Lia Assumpcao; Michael A. Choti; Ana L. Gleisner; Richard D. Schulick; Michael J. Swartz; Joseph M. Herman; Susan L. Gearhart; Timothy M. Pawlik

HYPOTHESIS Patients with rectal adenocarcinoma are at increased risk of locoregional recurrence compared with patients with colon cancer. This may affect the pattern of recurrence and survival rates following hepatic resection of liver metastases from rectal adenocarcinoma. DESIGN Retrospective review of a prospectively collected cancer center database. PATIENT AND METHODS From April 1, 1984, to December 31, 2005, 582 patients with liver metastases from a primary colorectal adenocarcinoma underwent hepatic resection. Clinical and pathological factors were analyzed using Cox regression analyses and log-rank tests. RESULTS Of 582 patients, 141 (24.2%) had liver metastases from a primary rectal tumor site. Treatment of the primary rectal tumor most frequently included chemoradiation therapy (59.6%) and low anterior resection (63.1%). Most rectal tumors were pathological stage T3/T4 (85.8%) and N1 (68.1%). Treatment directed at the hepatic metastases included resection only (81.5%), resection plus radiofrequency ablation (17.8%), or radiofrequency ablation only (0.7%). With a median follow-up time of 30.7 months, 80 of 141 patients (56.7%) developed recurrence; 23 patients (16.3%) developed recurrence in the pelvis. Of 23 patients with pelvic recurrence, 56.5% also developed recurrence in the liver. The 3- and 5-year survival rates for all patients were 62.4% and 36.4%, respectively. Of 80 patients who had a recurrence following hepatic metastectomy, 23 (28.8%) underwent another operation. Following repeat metastectomy, 3- and 5-year survival rates were 76.7% and 38.6%, respectively. CONCLUSIONS Following resection of hepatic rectal metastases, pelvic recurrence is relatively common, and most patients with pelvic recurrence will also develop recurrence in the liver. Surgery for recurrent disease following hepatic resection of rectal metastases is warranted among well-selected patients.


medical image computing and computer assisted intervention | 2008

Ablation Monitoring with Elastography: 2D In-vivo and 3D Ex-vivo Studies

Hassan Rivaz; Ioana Fleming; Lia Assumpcao; Gabor Fichtinger; Ulrike M. Hamper; Michael A. Choti; Gregory D. Hager; Emad M. Boctor

The clinical feasibility of 2D elastography methods is hindered by the requirement that the operator avoid out-of-plane motion of the ultrasound image during palpation, and also by the lack of volumetric elastography measurements. In this paper, we develop and evaluate a 3D elastography method operating on volumetric data acquired from a 3D probe. Our method is based on minimizing a cost function using dynamic programming (DP). The cost function incorporates similarity of echo amplitudes and displacement continuity. We present, to the best of our knowledge, the first in-vivo patient studies of monitoring liver ablation with freehand DP elastography. The thermal lesion was not discernable in the B-mode image but it was clearly visible in the strain image as well as in validation CT. We also present 3D strain images from thermal lesions in ex-vivo ablation. Good agreement was observed between strain images, CT and gross pathology.


Gastrointestinal Endoscopy | 2008

Air and fluid leak tests after NOTES procedures: a pilot study in a live porcine model (with videos)

Xavier Dray; Kathleen L. Gabrielson; Jonathan M. Buscaglia; Eun Ji Shin; Samuel A. Giday; Vihar C. Surti; Lia Assumpcao; Michael R. Marohn; Priscilla Magno; Laurie J. Pipitone; Susan K. Redding; Anthony N. Kalloo; Sergey V. Kantsevoy

BACKGROUND Transluminal access site closure remains a major challenge in natural orifice transluminal endoscopic surgery (NOTES). OBJECTIVE Our purpose was to develop in vivo leak tests for evaluation of the integrity of transgastric access closure. SETTINGS Survival experiments on 12 50-kg pigs. DESIGN AND INTERVENTIONS After a standardized transgastric approach to the peritoneal cavity and peritoneoscopy, the gastric wall incision was closed with T-bars (Wilson-Cook Medical, Winston-Salem, NC) deployed on both sides of the incision and then cinched together. Gastrotomy closure was assessed with air and fluid leak tests. The animals were observed for 1 week and then underwent endoscopic evaluation and necropsy. MAIN OUTCOME MEASUREMENTS (1) Leak-proof closure of the gastric wall incision. (2) Gastric incision healing 1 week after the procedure. RESULTS The mean intraperitoneal pressure increased 10.7 +/- 3.7 mm Hg during gastric insufflation when the air leak test was performed before closure compared with 0.9 +/- 0.8 mm Hg after transmural closure of the transgastric access site with T-bars (P < .001). Fluid leak tests demonstrated no leakage of liquid contrast from the stomach into the peritoneal cavity after closure. Necropsy in 1 week confirmed completeness of the gastric closure in all animals with full-thickness healing and no spillage of the gastric contents into the peritoneal cavity. LIMITATIONS Leak tests were only evaluated on an animal model. CONCLUSIONS Fluid and air leak tests are simple techniques to evaluate in vivo the adequacy of the transluminal access site closure after NOTES procedures. Leak-proof gastric closure resulted in adequate tissue approximation and full-thickness healing of the gastric wall incision.


Hpb | 2010

Intra-operative ultrasound elasticity imaging for monitoring of hepatic tumour thermal ablation

Mark G. van Vledder; Emad M. Boctor; Lia Assumpcao; Hassan Rivaz; Pezhman Foroughi; Gregory D. Hager; Ulrike M. Hamper; Timothy M. Pawlik; Michael A. Choti

BACKGROUND Thermal ablation is an accepted therapy for selected hepatic malignancies. However, the reliability of thermal ablation is limited by the inability to accurately monitor and confirm completeness of tumour destruction in real time. We investigated the ability of ultrasound elasticity imaging (USEI) to monitor thermal ablation. OBJECTIVES Capitalizing on the known increased stiffness that occurs with protein denaturation and dehydration during thermal therapy, we sought to investigate the feasibility and accuracy of USEI for monitoring of liver tumour ablation. METHODS A model for hepatic tumours was developed and elasticity images of liver ablation were acquired in in vivo animal studies, comparing the elasticity images to gross specimens. A clinical pilot study was conducted using USEI in nine patients undergoing open radiofrequency ablation for hepatic malignancies. The size and shape of thermal lesions on USEI were compared to B-mode ultrasound and post-ablation computed tomography (CT). RESULTS In both in vivo animal studies and in the clinical trial, the boundary of thermal lesions was significantly more conspicuous on USEI when compared with B-mode imaging. Animal studies demonstrated good correlation between the diameter of ablated lesions on USEI and the gross specimen (r = 0.81). Moreover, high-quality strain images were generated in real time during therapy. In patients undergoing tumour ablation, a good size correlation was observed between USEI and post-operative CT (r = 0.80). CONCLUSION USEI can be a valuable tool for the accurate monitoring and real-time verification of successful thermal ablation of liver tumours.


Gastrointestinal Endoscopy | 2009

Omentoplasty for gastrotomy closure after natural orifice transluminal endoscopic surgery procedures (with video)

Xavier Dray; Samuel A. Giday; Jonathan M. Buscaglia; Kathleen L. Gabrielson; Sergey V. Kantsevoy; Priscilla Magno; Lia Assumpcao; Eun Ji Shin; Susan K. Reddings; Kevin Woods; Michael R. Marohn; Anthony N. Kalloo

INTRODUCTION The utility of the greater omentum has not been assessed in transluminal access closure after natural orifice transluminal endoscopic surgery (NOTES) procedures. OBJECTIVE Our purpose was to evaluate the feasibility, efficacy, and safety of omentoplasty for gastrotomy closure. METHODS AND PROCEDURES Survival experiments in 9 female 40-kg pigs were randomly assigned to 3 groups: group A, endoscopic full-thickness resection (EFTR) for transgastric access and peritoneoscopy without closure; group B, ETFR and peritoneoscopy with omentoplasty (flap of omentum is pulled into the stomach and attached to the gastric mucosa with clips but no clips are used for gastrotomy closure itself); group C, balloon dilation for opening and peritoneoscopy followed by omentoplasty for closure. The animals were observed for 2 weeks and then underwent endoscopy and necropsy with histologic evaluation. RESULTS Transgastric opening and peritoneoscopy were achieved in all pigs. In groups B and C, a flap of omentum was easily placed to seal the gastrotomy and then attached to the gastric mucosa with 2 to 5 clips (median 4) in 7 to 20 minutes (median 15 minutes). In group A, peritonitis developed in all animals. In both groups B and C, all animals survived 15 days with no peritonitis and minimal adhesions outside the gastrotomy site. In addition, all achieved complete healing (transmural, n = 4; mucosal ulceration, n = 2) of the gastrotomy site. One animal in group B had an 18-mm abscess in the omental flap. LIMITATIONS Animal model, small sample size, lack of appropriate controls for group C. CONCLUSIONS Omentoplasty of the gastrotomy site is a technically feasible method to seal balloon-created transgastric access to the peritoneal cavity after NOTES procedures.


Abdominal Imaging | 2009

Functional MR imaging as a new paradigm for image guidance

Lia Assumpcao; Michael A. Choti; Timothy M. Pawlik; Jean Francois Gecshwind; Ihab R. Kamel

Guidance and monitoring of locoregional minimally invasive treatment for primary or secondary liver tumor are critical to ensuring success and efficacy of therapy. In this article, we review advanced MR imaging techniques, including MR spectroscopy, diffusion and perfusion MR imaging, which can provide essential in vivo physiologic and metabolic information. These innovative imaging techniques can provide potential additional criteria to assess tumor response in addition to the accepted yet often limited Response Evaluation Criteria in Solid Tumors (RECIST) and the European Association for the Study of the Liver (EASL) criteria, which are based on decrease of tumor size and lesion enhancement, respectively. In this article, we also discuss the role of tumor size and enhancement in addition to apparent diffusion coefficient (ADC) findings after radiofrequency ablation (RFA), transarterial chemoembolization (TACE), and radioembolization.

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Michael A. Choti

University of Texas Southwestern Medical Center

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Timothy M. Pawlik

The Ohio State University Wexner Medical Center

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Eun Ji Shin

Johns Hopkins University

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Michael R. Marohn

Johns Hopkins University School of Medicine

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Richard D. Schulick

University of Colorado Denver

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