Michael O. Meyers
University of North Carolina at Chapel Hill
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Journal of Gastrointestinal Surgery | 2009
Geoffrey P. Kohn; Joseph A. Galanko; Michael O. Meyers; Richard H. Feins; Timothy M. Farrell
IntroductionPositive volume–outcome relationships in esophagectomy have prompted support for regionalization of care; however, outcomes have not recently been analyzed. This study examines national trends in provision of esophagectomy and reassesses the volume–outcome relationship in light of changing practice patterns and training paradigms.MethodsThe Nationwide Inpatient Sample was queried from 1998 to 2006. Quantification of patients’ comorbidities was made using the Charlson Index. Using logistic regression modeling, institutions’ annual case volumes were correlated with risk-adjusted outcomes over time, as well as presence or absence of fellowship and residency training programs.ResultsA nationwide total of 57,676 esophagectomies were recorded. In-hospital unadjusted mortality fell from 12% to 7%. Adjusting for comorbidities, greater esophagectomy volume was associated with improvements in the incidence of most measured complications, though mortality increased once greater than 100 cases were performed. Hospitals supporting fellowship training or a surgical residency program did not have higher rates of mortality or total complications.ConclusionsThe current national mortality rate of 7% following esophagectomy is higher than is reported in most contemporary case series. A greater annual esophagectomy volume improves outcomes, but only up to a point. Current training paradigms are safe.
Journal of Clinical Oncology | 2013
Karyn B. Stitzenberg; Hanna K. Sanoff; Dolly Penn; Michael O. Meyers; Joel E. Tepper
PURPOSE Standard of care treatment for most stage I rectal cancers is total mesorectal excision (TME). Given the morbidity associated with TME, local excision (LE) for early-stage rectal cancer has been explored. This study examines practice patterns and overall survival (OS) for early-stage rectal cancer. METHODS All patients in the National Cancer Data Base diagnosed with rectal cancer from 1998 to 2010 were initially included. Use of LE versus proctectomy and use of adjuvant radiation therapy were compared over time. Adjusted Cox proportional hazards models were used to compare OS based on treatment. RESULTS LE was used to treat 46.5% of patients with T1 and 16.8% with T2 tumors. Use of LE increased steadily over time (P < .001). LE was most commonly used for women, black patients, very old patients, those without private health insurance, those with well-differentiated tumors, and those with T1 tumors. Proctectomy was associated with higher rates of tumor-free surgical margins compared with LE (95% v 76%; P < .001). Adjuvant radiation therapy use decreased over time independent of surgical procedure or T stage. For T2N0 disease, patients treated with LE alone had significantly poorer adjusted OS than those treated with proctectomy alone or multimodality therapy. CONCLUSION Guideline-concordant adoption of LE for treatment of low-risk stage I rectal cancer is increasing. However, use of LE is also increasing for higher-risk rectal cancers that do not meet guideline criteria for LE. Treatment with LE alone is associated with poorer long-term OS. Additional studies are warranted to understand the factors driving increased use of LE.
Academic Medicine | 2013
Jeffrey J. Dehmer; Keith D. Amos; Timothy M. Farrell; Anthony A. Meyer; Warren P. Newton; Michael O. Meyers
Purpose Data indicate that students are unprepared to perform basic medical procedures on graduation. The authors’ aim was to characterize graduating students’ experience with and opinions about these skills. Method In 2011, an online survey queried 156 fourth-year medical students about their experience with, and actual and desired levels of competence for, nine procedural skills (Foley catheter insertion, nasogastric tube insertion, venipuncture, intravenous catheter insertion, arterial puncture, basic suturing, endotracheal intubation, lumbar puncture, and thoracentesis). Students self-reported competence on a four-point Likert scale (4 = independently performs skill; 1 = unable to perform skill). Data were analyzed by analysis of variance and Student t test. A five-point Likert scale was used to assess student confidence. Results One hundred thirty-four (86%) students responded. Two skills were performed more than two times by over 50% of students: Foley catheter insertion and suturing. Mean level of competence ranged from 3.13 ± 0.75 (Foley catheter insertion) to 1.7 ± 0.7 (thoracentesis). A gap in desired versus actual level of competence existed for all procedures (P < .0001). There was a correlation between the number of times a procedure had been performed and self-reported competence for all skills except arterial puncture and suturing. Conclusions Participants had performed most skills infrequently and rated themselves as being unable to perform them without assistance. Strategies to improve student experience and competence of procedural skills must evolve to improve the technical competency of graduating students because their current competency varies widely.
Surgery | 1997
James C. Watson; James G Redmann; Michael O. Meyers; Robert C Alperin-Lea; Bryan M. Gebhardt; Joseph B. Delcarpio; Eugene A. Woltering
BACKGROUND Recurrence and mortality rates in patients with breast cancer correlate with the degree of tumor angiogenesis (angiogenic index). We have developed a novel angiogenesis model by using disks of fresh human placental vein that initiate an angiogenic response and exhibit linear radial capillary growth in culture. We hypothesized that the addition of human breast cancer cells to this human placental vein angiogenesis model would increase the incidence of angiogenesis and accelerate the rate of neovessel growth compared with vein disk cultured without tumor cells. METHODS To test this hypothesis, vein explants from seven human placentas were incorporated into clots of 0.3% fibrin in Medium 199 and fetal bovine serum with or without 1.5 x 10(5) T-47D (n = 6 placentas) or MCF-7 (n = 1 placenta) breast cancer cells. Statistical differences between the experimental (with breast cancer cells) and control (no added cells) cultures were determined by repeated measures ANOVA. RESULTS The proportion of disks exhibiting neovessel growth (initiation) by day 12 was significantly increased in the presence of T-47D cells (p < 0.05 at day 12, p < 0.001 at day 15). No statistical difference was seen in rates of neovessel growth (millimeters per day). Similar results were seen with MCF-7 cells. CONCLUSIONS Tumor enhancement of angiogenesis may occur by increased initiation of the angiogenic response. Subsequent vessel growth rates may be tumor independent. We predict that effective antiangiogenic therapies will block a tumors ability to augment angiogenesis initiation rather than subsequent neovessel growth.
Annals of Plastic Surgery | 2010
Charles Scott Hultman; Matthew Sherrill; Eric G. Halvorson; Clara N. Lee; John F. Boggess; Michael O. Meyers; Benjamin A. Calvo; Hong J. Kim
This study assesses the usefulness of the omentum in the reconstruction of complex perineal defects, following abdominoperineal resection or pelvic exenteration, for anorectal malignancy.Between 2000 and 2008, 70 patients (mean age: 59 years) with anorectal malignancy underwent abdominoperineal resection (n = 57) or pelvic exenteration (n = 13) and were reconstructed by primary repair alone (n = 13), primary repair with omentum (n = 16), myocutaneous flap alone (n = 28), or myocutaneous flap with omentum (n = 13). Patients with and without omental flaps were compared by Student t test and &khgr;2 analysis. Omental flaps were based on a single pedicle, tunneled in the retrocolic plane lateral to the ligament of Treitz, and transposed across the sacrum to the pelvic floor.In total, 29 patients had pelvic floor and perineal reconstruction with the omentum, and 41 patients had reconstruction without the omentum. Incidence of major pelvic complications (abscess, urinoma, deep vein thrombosis, flap dehiscence, hernia, bowel obstruction, fistula) was greater in the “no omentum” group (25/41 patients, 61%), compared with the “omentum” group (6/29 patients, 21%) (P < 0.01). No differences were observed regarding age, stage, incidence of radiotherapy, blood loss, length of stay, or mortality.Use of the omentum as a primary flap, or in combination with a myocutaneous flap, in the reconstruction of complex perineal defects, is associated with a decreased incidence of postoperative complications, strongly supporting the use of the omentum in pelvic floor reconstruction.
Journal of Surgical Research | 2012
Charles Scott Hultman; AnnaMarie Connolly; Eric G. Halvorson; Pamela A. Rowland; Michael O. Meyers; David C. Mayer; Amelia F. Drake; George F. Sheldon; Anthony A. Meyer
INTRODUCTION Few educational programs exist for medical students that address professionalism in surgery, even though this core competency is required for graduate medical education and maintenance of board certification. Lapses in professional behavior occur commonly in surgical disciplines, with a negative effect on the operative team and patient care. Therefore, education regarding professionalism should begin early in the surgeons formative process, to improve behavior. The goal of this project was to enhance the attitudes and knowledge of medical students regarding professionalism, to help them understand the role of professionalism in a surgical practice. METHODS We implemented a 4-h seminar, spread out as 1-h sessions over the course of their month-long rotation, for 4th-year medical students serving as acting interns (AIs) in General Surgery, a surgical subspecialty, Obstetrics/Gynecology, or Anesthesia. Teaching methods included lecture, small group discussion, case studies, and journal club. Topics included Cognitive/Ethical Basis of Professionalism, Behavioral/Social Components of Professionalism, Managing Yourself, and Leading While You Work. We assessed attitudes about professionalism with a pre-course survey and tracked effect on learning and behavior with a post-course questionnaire. We asked AIs to rate the egregiousness of 30 scenarios involving potential lapses in professionalism. RESULTS A total of 104 AIs (mean age, 26.5 y; male to female ratio, 1.6:1) participated in our course on professionalism in surgery. Up to 17.8% of the AIs had an alternate career before coming to medical school. Distribution of intended careers was: General Surgery, 27.4%; surgical subspecialties, 46.6%; Obstetrics/Gynecology, 13.7%; and Anesthesia, 12.3%. Acting interns ranked professionalism as the third most important of the six core competencies, after clinical skills and medical knowledge, but only slightly ahead of communication. Most AIs believed that professionalism could be taught and learned, and that the largest obstacle was not enough time in the curriculum. The most effective reported teaching methods were mentoring and modeling; lecture and journal club were the effective. Regarding attitudes toward professionalism, the most egregious examples of misconduct were substance abuse, illegal billing, boundary issues, sexual harassment, and lying about patient data, whereas the least egregious examples were receiving textbooks or honoraria from drug companies, advertising, self-prescribing for family members, and exceeding work-hour restrictions. The most important attributes of the professional were integrity and honesty, whereas the least valued were autonomy and altruism. The AIs reported that the course significantly improved their ability to define professionalism, identify attributes of the professional, understand the importance of professionalism, and integrate these concepts into practice (all P < 0.01). CONCLUSIONS Although medical students interested in surgery may already have well-formed attitudes and sophisticated knowledge about professionalism, this core competency can still be taught to and learned by trainees pursuing a surgical career.
Journal of Surgical Research | 2011
Michael O. Meyers; Anthony A. Meyer; Robyn D. Stewart; Elizabeth B. Dreesen; Patricia A. Lange; Timothy M. Farrell
BACKGROUND Opportunities for medical students to learn and perform technical skills during their clinical years have decreased. Alternative means to provide instruction are increasingly important. METHODS Third-year students were assigned to three weekly small group tutorial sessions during their surgery clerkship. One hour sessions covered the following: suturing/knot tying, tubes (Foley catheter/NG tube), and lines (i.v. placement/arterial puncture). Students used a self-reported checklist to report their experience performing these procedures in the hospital after being exposed to them in the skills sessions. These data were compared with results prior to the implementation of the skills curriculum. Results were compared by Fishers exact test. RESULTS Seventy-seven students had evaluable checklists during the control period, and 69 were evaluable during the study period. Participations in four specific skills were compared: Foley catheter placement, nasogastric tube insertion/removal, i.v. placement, and arterial stick. In all four skills, students were more likely to have performed the task after having been introduced to it in the skills sessions. For both Foley catheter placement (96% versus 90%; P = 0.05) and NG tube insertion/removal (70% versus 53%; P = 0.06) there was a trend toward a higher incidence of participation, although statistical significance was not met. However, for both IV placement (64% versus 18%; P = 0.0001) and arterial puncture (48% versus 18%; P = 0.0002) there were significant increases in participation between the study periods. CONCLUSIONS These results suggest that a small group technical skills curriculum facilitates learning of specific technical skills and appears to increase participation in all of the skills taught and assessed. This may be one strategy to introduce students to technical skills during the surgery clerkship and improve participation of these skills in the hospital setting.
European Journal of Cancer | 2010
Roshawn G. Watson; Filipe Muhale; Leigh B. Thorne; Jinsheng Yu; Bert H. O'Neil; Janelle M. Hoskins; Michael O. Meyers; Allison M. Deal; Joseph G. Ibrahim; Michael L Hudson; Christine M. Walko; Howard L. McLeod; James Todd Auman
Resistance to 5-fluorouracil (5-FU) represents a major contributor to cancer-related mortality in advanced colorectal cancer patients. Genetic variations and expression alterations in genes involved in 5-FU metabolism and effect have been shown to modulate 5-FU sensitivity in vitro, however these alterations do not fully explain clinical resistance to 5-FU-based chemotherapy. To determine if alterations of DNA copy number in genes involved in 5-FU metabolism-impacted clinical resistance to 5-FU-based chemotherapy, we assessed thymidylate synthetase (TYMS) and thymidine phosphorylase (TYMP) copy number in colorectal liver metastases. DNA copy number of TYMS and TYMP was evaluated using real time quantitative PCR in frozen colorectal liver metastases procured from 62 patients who were pretreated with 5-FU-based chemotherapy prior to surgical resection (5-FU exposed) and from 51 patients who received no pretreatment (unexposed). Gain of TYMS DNA copy number was observed in 18% of the 5-FU exposed metastases, while only 4% of the unexposed metastases exhibited TYMS copy gain (p = 0.036). No significant differences were noted in TYMP copy number alterations between 5-FU-exposed and -unexposed metastases. Median survival time was similar in 5-FU-exposed patients with metastases containing TYMS amplification and those with no amplification. However, TYMS amplification was associated with shorter median survival in patients receiving post-resection chemotherapy (hazard ratio = 2.7, 95% confidence interval = 1.1-6.6; p = 0.027). These results suggest amplification of TYMS amplification as a putative mechanism for clinical resistance to 5-FU-based chemotherapy and may have important ramifications for the post-resection chemotherapy choices for metastatic colorectal cancer.
American Journal of Surgery | 2014
Justin J. Baker; Michael O. Meyers; Jill S. Frank; Keith D. Amos; Karyn B. Stitzenberg; David W. Ollila
BACKGROUND Follow-up of patients with sentinel lymph node-positive stage III melanoma uses history, physical exam, and cross-sectional imaging. The aim of this study was to evaluate positron emission tomographic (PET)/computed tomographic (CT) scans in the detection of recurrence. METHODS From 2003 to 2009, a single-institution prospective database of all cutaneous melanoma patients was used to identify sentinel lymph node-positive stage III patients with disease-free survival >1 year and 1 restaging PET/CT scan. RESULTS Thirty-eight patients were identified, with a median follow-up period of 27.5 months. Seven (18%) developed recurrence (median time to recurrence, 25 months). Recurrences were detected as follows: 3 by patients, 1 by physician, 1 by PET/CT scan and lactate dehydrogenase, 1 by PET/CT scan, and 1 by brain magnetic resonance imaging. One hundred eight follow-up PET/CT scans were performed. Two of 38 patients had asymptomatic metastases detected by routine restaging PET/CT scan, and there were 9 scans with false-positive results. CONCLUSIONS With short follow-up, the utility of routine PET/CT scans in identifying unsuspected recurrence in patients with sentinel lymph node-positive stage III melanoma appears minimal.
Journal of Surgical Research | 2013
Raeshell S. Sweeting; Allison M. Deal; Omar H. Llaguna; Brian K. Bednarski; Michael O. Meyers; Jen Jen Yeh; Benjamin F. Calvo; Joel E. Tepper; Hong Jin Kim
BACKGROUND Local recurrence (LR) rates in patients with retroperitoneal sarcoma (RPS) are high, ranging from 40% to 80%, with no definitive studies describing the best way to administer radiation. Intraoperative electron beam radiation therapy (IOERT) provides a theoretical advantage for access to the tumor bed with reduced toxicity to surrounding structures. The goal of this study was to evaluate the role of IOERT in high-risk patients. METHODS An institutional review board approved, single institution sarcoma database was queried to identify patients who received IOERT for treatment of RPS from 2/2001 to 1/2009. Data were analyzed using the Kaplan-Meier method, Cox regression, and Fisher Exact tests. RESULTS Eighteen patients (median age 51 y, 25-76 y) underwent tumor resection with IOERT (median dose 1250 cGy) for primary (n = 13) and recurrent (n = 5) RPS. Seventeen patients received neoadjuvant radiotherapy. Eight high-grade and 10 low-grade tumors were identified. Median tumor size was 15 cm. Four patients died and two in the perioperative period. Median follow-up of survivors was 3.6 y. Five patients (31%) developed an LR in the irradiated field. Three patients with primary disease (25%) and two (50%) with recurrent disease developed an LR (P = 0.5). Four patients with high-grade tumors (57%) and one with a low-grade tumor (11%) developed an LR (P = 0.1). The 2- and 5-y OS rates were 100% and 72%. Two- and 5-y LR rates were 13% and 36%. CONCLUSIONS Using a multidisciplinary approach, we have achieved low LR rates in our high-risk patient population indicating that IOERT may play an important role in managing these patients.