Leonardo Alfonso Bustamante-Lopez
University of São Paulo
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Endoscopy International Open | 2016
Marianny Sulbaran; Eduardo Moura; Wanderley Marques Bernardo; Cintia Morais; Joel Oliveira; Leonardo Alfonso Bustamante-Lopez; Paulo Sakai; Klaus Mönkemüller; Adriana V. Safatle-Ribeiro
Background and study aims: Several studies have evaluated the utility of double-balloon enteroscopy (DBE) and capsule endoscopy (CE) for patients with small-bowel disease showing inconsistent results. The aim of this study was to determine the sensitivity and specificity of overtube-assisted enteroscopy (OAE) as well as the diagnostic concordance between OAE and CE for small-bowel polyps and tumors. Patients and methods: We conducted a systematic review and meta-analysis of studies in which the results of OAE were compared with the results of CE for the evaluation of small-bowel polyps and tumors. When data for surgically resected lesions were available, the histopathological results of OAE and surgical specimens were compared. The sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio for the diagnosis of small-bowel polyps and tumors were analyzed. Secondarily, the rates of diagnostic concordance and discordance between OAE and CE were calculated. Results: There were 15 full-length studies with a total of 821 patients that met the inclusion criteria. The pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were as follows: 0.89 (95 % confidence interval [CI] 0.84 – 0.93), with heterogeneity χ2 = 41.23 (P = 0.0002) and inconsistency (I 2) = 66.0 %; 0.97 (95 %CI 0.95 – 0.98), with heterogeneity χ2 = 45.27 (P = 0.07) and inconsistency (I 2) = 69.1 %; 16.61 (95 %CI 3.74 – 73.82), with heterogeneity Cochrane’s Q = 225.19 (P < 0.01) and inconsistency (I 2) = 93.8 %; and 0.14 (95 %CI 0.05 – 0.35), with heterogeneity Cochrane’s Q = 81.01 (P < .01) and inconsistency (I 2) = 82.7 %, respectively. A summary receiver operating characteristic curve (SROC) curve was constructed, and the area under the curve (AUC) was 0.97. Conclusion: OAE is an accurate test for the detection of small-bowel polyps and tumors. OAE and CE have a high diagnostic concordance rate for small-bowel polyps and tumors. This study was registered in the PROSPERO international database (www.crd.york.ac.uk/prospero/) with the study number CRD42015016000.
ABCD. Arquivos Brasileiros de Cirurgia Digestiva (São Paulo) | 2015
Sergio Carlos Nahas; Caio Sergio Rizkallah Nahas; Leonardo Alfonso Bustamante-Lopez; Rodrigo Ambar Pinto; Carlos Frederico Sparapan Marques; Fábio Guilherme Campos; Ivan Ceconello
RACIONAL: Câncer colorretal e o tipo mais comum das neoplasias gastrointestinais. Ha muitas controversias na literatura acerca do valor prognostico do sitio da neoplasia. Muitos estudos revelam maiores taxas de sobrevida para tumores em colon direito, com piora do prognostico a medida que as lesoes se situam mais distalmente. OBJETIVO: Analisar os resultados do tratamento cirurgico de pacientes com câncer de colon direito estadios I-IV operados em um periodo de dez anos e identificar os fatores prognosticos que foram associados com menor sobrevida global. METODOS: Em 10 anos, 187 pacientes foram submetidos a colectomia direita com intencao curativa. Foram estudados os seguintes fatores: genero, idade, localizacao do tumor, o numero de linfonodos obtidos no especime, comprometimento linfonodal, estadio T e presenca de metastases a distância. Estes fatores foram avaliados quanto a possibilidade de serem indicadores prognosticos na sobrevida em cinco anos. RESULTADOS: A idade media foi de 65 (±12) anos e 105 (56,1%) eram mulheres. A localizacao, mas comum foi o colon ascendente (48,1%), seguido do ceco (41,7%) e o ângulo hepatico (10,2%). A media de tempo de internacao hospitalar foi 14 (±2.8) dias. A distribuicao do estadio T foi T1 (4,8%), T2 (7,5%), T3 (74,9%) e T4 (12,8%). Acometimento linfonodal ocorreu em 46,0% e metastases a distância em 3,7%. Um minimo de 12 linfonodos ressecados foram obtidos em 87,2% dos especimes cirurgicos. Em 84.5% os tumores eram nao-mucinosos. A media de sobrevida foi de 38,3 (±30.8) meses. A sobrevida geral foi afetada pelo estadio T, N, M e pelo estadio final. O acometimento linfonodal (RR=2,06) e os estadios III/IV (RR=2,81) foram fatores prognosticos negativos independentes. CONCLUSOES: Estadio avancado e envolvimento linfonodal foram os fatores associados com a pior sobrevida em longo prazo.
Arquivos brasileiros de cirurgia digestiva : ABCD = Brazilian archives of digestive surgery | 2015
Sergio Carlos Nahas; Caio Sergio Rizkallah Nahas; Leonardo Alfonso Bustamante-Lopez; Rodrigo Ambar Pinto; Carlos Frederico Sparapan Marques; Fábio Guilherme Campos; Ivan Ceconello
Background Colorectal cancer is one of the most common malignancies in the world. There are many controversies in the literature about the prognostic value of primary tumor location. Many studies have shown higher survival rates for tumors in the right colon, and worse prognosis for lesions located more distally in the colon. Aim To analyze the results of surgical treatment of right-sided colon cancers patients operated in one decade period and identify the prognostic factors that were associated with lower overall survival in stages I-IV patients. Methods A retrospective review from the prospectively collected database identified 178 patients with right-sided colon cancer surgically treated with curative intent. Demographic factors (gender and age), tumor factors (site, T stage, N stage, M stage, histological type and tumor differentiation), and lymph node yield were extracted to identify those associated with lower overall survival. Results Mean age was 65 (±12) years old, and 105 (56.1%) patients were female. Most common affected site was ascending colon (48.1%), followed by cecum (41.7%) and hepatic flexure (10.2%). Mean length of hospital stay was 14 (±2.8) days. T stage distribution was T1 (4.8%), T2 (7.5%), T3 (74.9%), and T4 (12.8%). Nodal involvement was present in 46.0%, and metastatic disease in 3.7%. Twelve or more lymph nodes were obtained in 87.2% of surgical specimens and 84.5% were non-mucinous tumors. Mean survival time was 38.3 (±30.8) months. Overall survival was affected by T stage, N stage, M stage, and final stage. Lymph node involvement (OR=2.06) and stage III/IV (OR=2.81) were independent negative prognostic factors. Conclusion Right-sided colon cancer presented commonly at advanced stage. Advanced stage and lymph node involvement were factors associated with poor long term survival.
International Journal of Colorectal Disease | 2017
Leonardo Alfonso Bustamante-Lopez; Caio Sergio Rizkallah Nahas; Sergio Carlos Nahas; Ulysses Ribeiro; Carlos Frederico Sparapan Marques; Guilherme Cutait de Castro Cotti; A. Rocco; Ivan Cecconello
IntroductionRectal cancer patients frequently present with locally advanced disease for which the standard of care includes neoadjuvant chemoradiotherapy followed by total mesorectal excision. Positive lymph nodes are one of the most powerful risk factors for recurrence and survival in colorectal cancer. In the absence of specific rectal guidelines, the literature recommends to the pathologist to optimize the number of rectal lymph nodes (LN) retrieved. We made a literature review in order to identify factors that could potentially affect the number of LN retrieved in specimens of patients with rectal cancer treated by chemoradiotherapy (CRT) followed by total mesorectal excision (TME).ResultsAge did not have a significant effect on LN yield. The effect of sex on LN number is not consistent in the literature. Most of the papers did not find a relationship between lower LN obtained and gender. Laparoscopy for primary rectal cancer is associated with a greater number of LN as well as short-term benefits. Tumors in the upper rectum are associated with a higher number of LN than those in the mid and lower rectum. The type of surgery had no effect on lymph node yield either. Tumors with complete or almost complete pathologic regression were exactly the ones with lower number of lymph nodes detected. Approximately one-third of patients with neoadjuvant treatment had less than 12 LN yield.ConclusionThe tumor regression grade is the most important factor for the decrease in the number of lymph nodes.
Archive | 2015
José Marcio Neves Jorge; Angelita Habr-Gama; Leonardo Alfonso Bustamante-Lopez
Regardless of whether adjuvant or neoadjuvant radiotherapy is used, pelvic irradiation adversely affects anorectal function. Although survival remains the primary goal in treatment, maintaining adequate anal continence is necessary for good quality of life. Radiation damages to the internal anal sphincter and the myenteric cells are frequently seen. Other mechanisms of continence affected by radiotherapy include decreased stool consistency, impaired rectal capacity, and decreased anorectal sensation. These adverse effects are associated with an increasing indication of sphincter-preserving operations, and demand for improved radiation techniques and more favorable postoperative functional results. Symptoms of urgency and fecal incontinence are common after anterior resection with or without neoadjuvant chemoradiotherapy, but generally resolve within the first 2 years after surgery. In patients with persistent symptoms of fecal incontinence, conservative therapy including biofeedback should be offered.
Arquivos brasileiros de cirurgia digestiva : ABCD = Brazilian archives of digestive surgery | 2015
Caio Sergio Rizkallah Nahas; Sergio Carlos Nahas; Carlos Frederico Sparapan Marques; Rafael Schmerling; Leonardo Alfonso Bustamante-Lopez; Ulysses Ribeiro Junior; Ivan Cecconello
The gastrointestinal stromal tumor (GIST) is a rare type of tumor that expresses CD117 oncogene that can be detected by immunohistochemistry2. The most common sites of GISTs are stomach (70%), and small intestine (20%), while rectum is comprised in only 3% of the cases5. Although a rare condition, the GIST located in the distal rectum may require an abdominoperineal resection. There is no data to support the use of Imatinib (Gleevec from Novartis, Basel, Switzerland), a selective inhibitor of tyrosine quinase, as neoadjuvant therapy. However, the last session consensus for the treatment of GIST, suggests that this form of therapy can be used in some cases where anal sphincter is involved7. The objective of this report is to describe a case of GIST distal rectum in the rectovaginal septum with partial invasion of the anal sphincter, which was successfully treated by neoadjuvant therapy with imatinib followed by the technique of transanal endoscopic microsurgery (TEM). The results are compared with experience in the literature.
International Journal of Surgery | 2018
Leonardo Alfonso Bustamante-Lopez; Caio Sergio Rizkallah Nahas; Sergio Carlos Nahas; Carlos Frederico Sparapan Marques; Rodrigo Ambar Pinto; Guilherme Cutait de Castro Cotti; Antonio Rocco Imperiale; Evandro Sobroza de Mello; Ulysses Ribeiro Junior; Ivan Cecconello
Studies have suggested that the use of neoadjuvant chemoradiation results in a lower lymph nodes yield in rectal cancer patients. OBJECTIVE To evaluate factors associated with less than 12 lymph nodes harvested on patients with rectal cancer treated with preoperative chemoradiotherapy followed by total mesorectal excision. PATIENTS This was a cohort/retrospective single cancer center study. Low and mid locally advanced rectal cancer or T2N0 under risk of sphincter resection underwent chemoradiotherapy followed by total mesorectal excision with curative intent. Chemotherapy consisted of 5-FU and leucovorin IV. Total dose of pelvic radiation was 5040 Gys. All patients were staged and restaged by digital rectal examination, proctoscopy, colonoscopy, CT of abdomen and chest, and MRI of the pelvis. Patients were stratified in two groups: ≥12 and < 12 L N retrieved. The possible factors affecting number of LN were analyzed. RESULTS 95 patients met the inclusion criteria. Mean LN harvest was 23.2 (3-67). 81 patients (85%) had ≥12 L N. Gender, age, tumor size, tumor stage, tumor location, length of specimen, presence of LN involvement, type of surgery, and surgical access showed no association with number of LN retrieved. Only pathological complete response showed a statistically significant association with <12 L N on univariate (p = 0.004) and multivariate analyses (p = 0.002). LIMITATIONS Data were collected retrospectively. The number of patients disparity between the two groups. CONCLUSIONS Complete pathologic response is associated with <12 L N harvested. Thus, the number of lymph nodes should not be used as a surrogate for oncologic adequacy of resection in patients with pathologic complete response.
Endoscopy International Open | 2018
Marianny Sulbaran; Fabio G. Campos; Ulysses Ribeiro; Humberto Kishi; Paulo Sakai; E. G. H. de Moura; Leonardo Alfonso Bustamante-Lopez; M. Tomitão; Sergio Carlos Nahas; Ivan Cecconello; Adriana V. Safatle-Ribeiro
Background and study aims To determine the clinical features associated with advanced duodenal and ampullary adenomas in familial adenomatous polyposis. Secondarily, we describe the prevalence and clinical significance of jejunal polyposis. Patients and methods This is a single center, prospective study of 62 patients with familial adenomatous polyposis. Duodenal polyposis was classified according to Spigelman and ampullary adenomas were identified. Patients with Spigelman III and IV duodenal polyposis underwent balloon assisted enteroscopy. Predefined groups according to Spigelman and presence or not of ampullary adenomas were related to the clinical variables: gender, age, family history of familial adenomatous polyposis, type of colorectal surgery, and type of colorectal polyposis. Results Advanced duodenal polyposis was present in 13 patients (21 %; 9 male) at a mean age of 37.61 ± 13.9 years. There was a statistically significant association between family history of the disease and groups according to Spigelman ( P = 0.03). Seven unrelated patients (6 male) presented ampullary adenomas at a mean age of 36.14 ± 14.2 years. The association between ampullary adenomas and extraintestinal manifestations was statistically significant in multivariate analysis ( P = 0.009). Five endoscopic types of non-ampullary adenoma were identified, showing that lesions larger than 10 mm or with a central depression presented foci of high grade dysplasia. Among 28 patients in 12 different families, a similar Spigelman score was identified; 10/12 patients (83.3 %) who underwent enteroscopy presented small tubular adenomas with low grade dysplasia in the proximal jejunum. Conclusions Advanced duodenal polyposis phenotype may be predictable from disease severity in a first-degree relative. Ampullary adenomas were independently associated with the presence of extraintestinal manifestations.
Revista Espanola De Enfermedades Digestivas | 2017
Leonardo Alfonso Bustamante-Lopez; Marianny Sulbaran; Sergio Carlos Nahas; Eduardo Guimaräes Horneaux de Moura; Caio Sergio Rizkallah Nahas; Carlos Federico Marques; Christiano Sakai; Ivan Ceconello; Paulo Sakai
BACKGROUND Indications for colostomy in colorectal diseases are obstruction of the large bowel, such as in cancer, diverticular disease in the acute phase, post-radiotherapy enteritis, complex perirectal fistulas, anorectal trauma and severe anal incontinence. Some critically ill patients cannot tolerate an exploratory laparotomy, and laparoscopic assisted colostomy also requires general anesthesia. OBJECTIVE To evaluate the feasibility, safety and efficacy of performing colostomy assisted by colonoscopy and percutaneous colopexy. MATERIALS AND METHODS Five pigs underwent endoscopic assisted colostomy with percutaneous colopexy. Animals were evaluated in post-operative days 1, 2, 5 and 7 for feeding acceptance and colostomy characteristics. On day 7 full colonoscopy was performed on animals followed by exploratory laparotomy. RESULTS Average procedure time was 27 minutes (21-54 min). Postoperative mobility and feeding of animals were immediate after anesthesia recovery. Position of the colostomy, edges color, appearance of periostomal area, as well as its function was satisfactory in four animals. Retraction of colostomy was present in one pig. The colonoscopy and laparotomy control on the seventh day were considered as normal. A bladder perforation that was successfully repaired through the colostomy incision occurred in one pig. The main limitation of this study is its experimental nature. CONCLUSION Endoscopic assisted colostomy with percutaneous colopexy proves to be a safe and effective method with low morbidity for performing colostomy in experimental animals, with possible clinical application in humans.
Clinics | 2017
Caio Sergio Rizkallah Nahas; Sergio Carlos Nahas; Ulysses Ribeiro-Junior; Leonardo Alfonso Bustamante-Lopez; Carlos Frederico Sparapan Marques; Rodrigo Ambar Pinto; Antonio Rocco Imperiale; Guilherme Cutait de Castro Cotti; William Carlos Nahas; Daher C. Chade; Dariane Sampaio Piato; Fabio de Freitas Busnardo; Ivan Cecconello
OBJECTIVES: This study sought to determine the clinical and pathological factors associated with perioperative morbidity, mortality and oncological outcomes after multivisceral en bloc resection in patients with colorectal cancer. METHODS: Between January 2009 and February 2014, 105 patients with primary colorectal cancer selected for multivisceral resection were identified from a prospective database. Clinical and pathological factors, perioperative morbidity and mortality and outcomes were obtained from medical records. Estimated local recurrence and overall survival were compared using the log-rank method, and Cox regression analysis was used to determine the independence of the studied parameters. ClinicalTrials.gov: NCT02859155. RESULTS: The median age of the patients was 60 (range 23-86) years, 66.7% were female, 80% of tumors were located in the rectum, 11.4% had stage-IV disease, and 54.3% received neoadjuvant chemoradiotherapy. The organs most frequently resected were ovaries and annexes (37%). Additionally, 30.5% of patients received abdominoperineal resection. Invasion of other organs was confirmed histologically in 53.5% of patients, and R0 resection was obtained in 72% of patients. The overall morbidity rate of patients in this study was 37.1%. Ureter resection and intraoperative blood transfusion were independently associated with an increased number of complications. The 30-day postoperative mortality rate was 1.9%. After 27 (range 5-57) months of follow-up, the mortality and local recurrence rates were 23% and 15%, respectively. Positive margins were associated with a higher recurrence rate. Positive margins, lymph node involvement, stage III/IV disease, and stage IV disease alone were associated with lower overall survival rates. On multivariate analysis, the only factor associated with reduced survival was lymph node involvement. CONCLUSIONS: Multivisceral en bloc resection for primary colorectal cancer can be performed with acceptable rates of morbidity and mortality and may lead to favorable oncological outcomes.