Felipe A B Maegawa

Interests

Research

Surgical outcomes research focusing on oncology and general surgery. Cost-effectiveness applied to surgical practice and surgical decision making.

Teaching

Clinical teaching for medical students and residents. Technical skills teaching in the operating room.

Courses

No activities entered.

Scholarly Contributions

Chapters

• Krouse, R. S., & Maegawa, F. B. (2017). Palliative and End of Life Treatment. In Rectal Cancer: Modern Approaches to Treatment(pp 355 - 366). Springer. doi:10.1007/978-3-319-16384-0

Journals/Publications

• Aziz, H., Zeeshan, M., Jie, T., & Maegawa, F. B. (2019). Neoadjuvant Chemoradiation Therapy Is Associated with Adverse Outcomes in Patients Undergoing Pancreaticoduodenectomy for Pancreatic Cancer. The American surgeon, 85(11), 1276-1280.
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  The use of neoadjuvant chemoradiation therapy in patients with pancreatic adenocarcinoma is emerging as an acceptable therapy option. The effects of neoadjuvant therapy on 30 days' outcomes in patients with pancreatic cancer are not well defined in the literature. NSQIP (2009-2012) was used. Only patients with a diagnosis of pancreatic cancer and those who underwent a Whipple were included in the analysis. Patient who underwent neoadjuvant chemoradiation therapy were compared with those who did not receive therapy. Main outcome measures were as follows: complications, ≥2 units of blood transfusions, length of stay, readmission rates, return to the operating room, and 30-day mortality. A total of 1445 patients (395: neoadjuvant chemoradiation and 1050: no neoadjuvant therapy) were identified. The mean age was 67 ± 12 years, and 51 per cent of the patients were male. Neoadjuvant chemoradiation therapy was associated with increase in readmission rates (18% 12.2%, 0.02), unanticipated return to the operating room (2.3% 1.1%, 0.03) with no difference in mortality rates. Neoadjuvant chemoradiation therapy is associated with increase in inhospital complications. These differences in outcomes may be explained by the more advance stage of pancreatic cancer in these subsets of patients. Resource utilization and preoperative rehabilitation are of utmost significance to overcome this rise in complications associated with neoadjuvant chemoradiation therapy.
• Maegawa, F. B., Shehorn, L., Aziz, H., Kettelle, J., Jie, T., & Riall, T. S. (2019). Association Between Noninvasive Fibrosis Markers and Postoperative Mortality After Hepatectomy for Hepatocellular Carcinoma. JAMA network open, 2(1), e187142.
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  The selection criteria for hepatectomy for hepatocellular carcinoma (HCC) is not well established. The role of noninvasive fibrosis markers in this setting is unknown in the US population.
• Frankl, J., Michailidou, M., & Maegawa, F. (2017). Parastomal gallbladder hernia in a septic patient. Radiology case reports, 12(3), 508-510.
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  Parastomal gallbladder herniation is a rare complication of enterostomies with only 6 previously reported cases. Most cases have occurred in elderly women. Patients typically presented with acute abdominal pain and the majority was managed operatively. Here, we report the clinical course of an 88-year-old female who presented with signs of sepsis and minimal abdominal symptoms. She was subsequently found to have a parastomal gallbladder herniation and bacteremia. Given the patient's multiple comorbidities, she was managed nonoperatively with manual reduction of the parastomal hernia and antibiotics.
• Ilyas, M. I., Zangbar, B., Nfonsam, V. N., Maegawa, F. A., Joseph, B. A., Patel, J. A., & Wexner, S. D. (2017). Are there differences in outcome after elective sigmoidectomy for diverticular disease and for cancer? A national inpatient study. Colorectal disease : the official journal of the Association of Coloproctology of Great Britain and Ireland, 19(3), 260-265.
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  The postoperative outcome after elective sigmoidectomy for diverticulitis has not been compared to that for cancer. The study aimed to evaluate the differences in the postoperative outcome after sigmoidectomy for diverticular disease and cancer.
• Maegawa, F. B. (2016). Preoperative thrombocytopenia and outcomes of hepatectomy in hepatocellular carcinoma. J Surg Res, 498-505. doi:10.1016/j.jss.2015.08.038
• Venkat, R., Hannallah, J. R., Krouse, R. S., & Maegawa, F. B. (2016). Preoperative thrombocytopenia and outcomes of hepatectomy for hepatocellular carcinoma. The Journal of surgical research, 201(2), 498-505.
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  Platelet count is known to be an indirect indicator of portal hypertension but is not a part of the model for end-stage liver disease (MELD) score or the Child-Pugh score for risk stratification in hepatobiliary surgery.
• Maegawa, F. A., Damerau, E. F., Beltrame-Botelho, I. T., Lopes, A., Emmanuelle-Machado, P., Steindel, M., & Grisard, E. C. (2003). Autochthonous Chagas' disease in Santa Catarina State, Brazil: report of the first case of digestive tract involvement. Revista da Sociedade Brasileira de Medicina Tropical, 36(5), 609-12.
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  We report the first case of digestive tract pathology (megaesophagus) determined by Trypanosoma cruzi infection in Santa Catarina State, southern Brazil. A 63-year-old female had presumptive clinical diagnosis of Chagas' disease, which was confirmed by imaging (endoscopy and esophagogram) and immunological methods. Further molecular diagnosis was carried out with esophagus and blood samples collected during corrective surgery. Polymerase chain reaction tested positive for Trypanosoma cruzi in both esophagus and buffy coat samples.
• Maegawa, F. A., de Souza, J. A., de Araújo, E. J., Koh, I. H., d'Acampora, A. J., de Farias, D. C., Mengarda, J., Volpato, D., da Silva, L. G., & de Córdova, C. S. (2005). Study of the Reconstruction of the Ileocecal Valve in Beagles.. Acta cirurgica brasileira, 20(1), 55-63.
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  The importance of keeping the ileocecal valve in the intestinal ressections has been reported by several authors. When preserved, the ileocecal valve was related to a longer survival and prevention of the short bowel syndrome, due to its ability to block the colonic content reflux into the ileum and to avoid the rapid empting of the ileal content into the cecum. It was assessed a tecnique of ileocecal valve reconstitution, based on vesicoureteral anti-reflux tecniques.
• Desai, C. S., Khan, K. M., Megawa, F. B., Rilo, H., Jie, T., Gruessner, A., & Gruessner, R. (2013). Influence of liver histopathology on transaminitis following total pancreatectomy and autologous islet transplantation. Digestive diseases and sciences, 58(5), 1349-54.
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  In type 1 diabetics undergoing allogenic islet transplants, transaminitis and portal vein thrombosis (PVT) after transhepatic portal infusion of islets may be related to infusion pressure and the purity of islets. Complications of intraoperative portal infusion of islets in patients with chronic pancreatitis undergoing a total pancreatectomy (TP) and autologous islet transplant (AIT) and the relationship to liver histopathology have not been examined.
• Amini, A., Patanwala, A. E., Maegawa, F. B., Skrepnek, G. H., Jie, T., Gruessner, R. W., & Ong, E. S. (2012). Effect of epidural analgesia on postoperative complications following pancreaticoduodenectomy. American journal of surgery, 204(6), 1000-4; discussion 1004-6.
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  The purpose of this study was to evaluate the effect of epidural analgesia use on postoperative complications in patients undergoing pancreaticoduodenectomy.
• Desai, C. S., Maegawa, F. B., Gruessner, A. C., Gruessner, R. W., Gruesner, R. W., & Khan, K. M. (2012). Age-based disparity in outcomes of intestinal transplants in pediatric patients. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons, 12 Suppl 4, S43-8.
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  Outcomes of intestinal transplants (ITx; n = 977) for pediatric patients are examined using the United Network for Organ Sharing data from 1987 to 2009. Recipients were divided into four age groups: (1)
• Vijayasekaran, A., Maegawa, F., & Guerrero, M. (2012). A rare finding of an ectopic parathyroid gland within a cervical thymic cyst presenting as a lateral neck mass. The American surgeon, 78(3), E171-2.
• Maegawa, F. A., & Tonussi, C. R. (2003). The L-arginine/nitric oxide/cyclic-GMP pathway apparently mediates the peripheral antihyperalgesic action of fentanyl in rats. Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas, 36(12), 1701-7.
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  There are only a few studies on the molecular mechanisms underlying the peripheral antihyperalgesic effect of opioids. The aim of this study was to investigate the molecular bases of the peripheral antihyperalgesic effect of fentanyl in a model of prostaglandin-induced chemical hyperalgesia. Prostaglandin E2 (1.4 nmol) injected into one hind paw of male Wistar rats (200-250 g, N = 6 in each experimental or control group) pretreated with indomethacin (2.5 mg/kg) potentiated the nocifensive response to formalin (1%) injection made 60 min later. Drugs applied locally 30 min after prostaglandin E2 induced the following effects: fentanyl (0.1-1.0 nmol) caused a dose-dependent reversal of the hyperalgesic state, naloxone (2 nmol) co-injected with fentanyl (1 nmol) completely reversed the antihyperalgesic effect, Nomega-nitro-L-arginine (NOARG, 0.05-0.2 mol) in combination with fentanyl (1.0 nmol) caused a dose-dependent inhibition of the antihyperalgesic effect of fentanyl, co-administration of L-arginine (0.5 mol) with NOARG (0.2 mol) plus fentanyl (1.0 nmol) fully restored the antihyperalgesic effect, and the cyclic-GMP phosphodiesterase inhibitor UK-114,542-27 (5-[2-ethoxy-5-(morpholinylacetyl) phenyl]-1,6-dihydro-1-methyl-3-propyl-7H-pyrazolo [4,3-d]-pyrimidin-7-one methanesulfonate monohydrate; 0.5-2.0 mol) potentiated a subeffective dose of fentanyl (0.1 nmol) in a dose-dependent manner. However, UK-114,542-27 (2.0 mol) injected alone did not produce this antihyperalgesic effect. Systemically administered fentanyl (1.0 nmol, sc) did not cause antinociception. Taken together, these results support the view that fentanyl reverses prostaglandin E2-induced hyperalgesia, probably by activating an opioid receptor at the periphery, and furthermore the L-arginine/nitric oxide/cyclic-GMP pathway may mediate this peripheral effect of fentanyl.
• de Souza, I. R., Muniz, Y. C., de M Saldanha, G., Alves Junior, L., da Rosa, F. C., Maegawa, F. A., Susin, M. F., de S Lipinski, M., & Petzl-Erler, M. L. (2003). Demographic and genetic structures of two partially isolated communities of Santa Catarina Island, southern Brazil. Human biology, 75(2), 241-53.
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  The objectives of this study were to analyze the population structure and genetic variability of two communities, Costa da Lagoa (CLG) and São João do Rio Vermelho (SJRV), located on Santa Catarina Island in southern Brazil. The two populations descend from Azores Archipelago immigrants (Portuguese), with a minor contribution of sub-Saharan Africans and Amerindians. To estimate the relative contribution of the different ethnic groups to the current gene pool of the two communities, values of admixture were obtained using the weighted least-squares method based on allelic frequencies of the loci ABO, RHD-RHCE, GPA-GPB (MNSs), HBB, HP, TF, CP, AK, and ACP1. The origins of the studied populations can be quantified as follows: for CLG, sub-Saharan Africans (A) = 17.3%, Iberian Europeans (P) = 75.0%, and Southern Amerindians (I) = 7.7%; for SJRV, A = 48.8%, P = 44.5%, and I = 6.7%. Because haplotype frequencies of the GPA-GPB loci in SJRV were unusual, possibly as a consequence of random genetic drift, the values of admixture were recalculated after exclusion of GPA-GPB, as follows: A = 28.0%; P = 53.3%, and I = 18.7%. The total diversity (HT) was estimated as 42.29%, of which 99.6% can be attributed to the intrapopulational variability (HS). The interpopulational genetic variation (or standard distance, DST) corresponds to 0.19%, while the gene differentiation coefficient is 0.28%, indicative of low genetic difference. These results led to the conclusion that random genetic drift may have had an important effect on the Costa da Lagoa community, while presently gene flow might be the predominant evolutionary factor potentially capable of changing allele frequencies in SJRV.