Carlos Chan

Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpam, The Federal District, Mexico

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Publications (43)78.08 Total impact

  • Pancreas 08/2014; 43(6):971-972. · 3.01 Impact Factor
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    ABSTRACT: To follow up patients with pseudotumoral chronic pancreatitis (PCP) to assess their outcome and identify an optimal surveillance interval.
    World journal of gastroenterology : WJG. 07/2014; 20(26):8612-6.
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    ABSTRACT: Few studies compare the direct impact of pancreatoduodenectomy (PD) on the patient's quality of life (QOL). The effect of PD in QOL, comparing the preoperative vs. postoperative status, was analyzed. A prospective single-center study was performed. PD patients in a 2-year period were included. A general QOL instrument was applied preoperative, 1, 3, 6, and 12 months after surgery and compared with national norms. Thirty-seven patients were recruited. Twenty of 37 were female. Ampullary carcinoma 14/37, ductal adenocarcinoma in 9/37, and other malignant neoplasms 14/37 were diagnosed. Mortality was absent; 48.6% had complications, 13.5 % required reoperation. Three (median) and 4 (mode) questionnaires were answered per individual. 85 % answered the last questionnaire. 4/37 had cancer related death before a year. Median follow-up was 29 (3-72) months. QOL diminished a month after surgery, physical function (67 vs 40, p<0.0001) and emotional role (37 vs 17, p<0.032) did so significantly. Three months after surgery QOL improved yet not significantly. Six and 12 months postoperatively, physical role (9 vs 49, p=0.001), physical pain (51 vs 71, p=0.01), social function (52 vs 63, p=0.014), vitality (54 vs 64, p=0.018), and emotional role (41 vs 69, p=0.006) improved significantly. PD has a favorable impact in quality of life as demonstrated by the improvement of most parameters assessed in the postoperative period.
    Journal of Gastrointestinal Surgery 05/2012; 16(7):1341-6. · 2.36 Impact Factor
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    ABSTRACT: Biliary complications after orthotopic liver transplantation (OLT) are multifactorial in origin. In most series, the frequency of such complications ranges from 5-20%. Most can be treated by endoscopy and/or interventional radiology. For cases in which this option is not successful, surgical approach is indicated. We report the results of reoperation using an intrahepatic bilioenteric anastomosis. The medical charts of patients with biliary complications after OLT during a 10-year period (1997-2007), who failed to respond to nonsurgical treatment and were surgically treated, were reviewed. Roux-en-Y hepatojejunostomy was performed. Segments IV and V were partially removed after cutting the hilar plate, thus obtaining healthy ducts without ischemic or inflammatory reaction and allowing a wide hepatojejunostomy. Five cases (8.4%) with biliary complications after duct-to-duct anastomosis not amenable to further endoscopic management or interventional radiology were identified. Hepaticojejunostomy was achieved in all cases (wide, tension-free, nonischemic, fine hydrolyzable sutures), and segments IV and V were partially removed. No cholangitis, jaundice, and liver function test abnormalities were present in the postoperative. Mean follow-up was 24 months. Only one patient died of causes not related to bile duct reconstruction during follow-up. Intrahepatic hepatojejunostomy with partial resection of segments IV and V offers an excellent therapeutic alternative for biliary complications that require a surgical approach after OLT.
    World Journal of Surgery 02/2009; 33(3):534-8. · 2.35 Impact Factor
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    ABSTRACT: Bile duct injuries related to laparoscopic and/or open cholecystectomy are a frequent finding and require surgical treatment. Complete obstruction is due to either intentionally or unintentionally placed ligatures or clips. The intentional application is usually performed to "facilitate identification of the duct by bile duct dilation." Considering that we are a national referral center for such injuries, we decided to analyze our cases of voluntary and involuntary duct ligation after iatrogenic bile duct injury. We reviewed the files of patients with voluntary or involuntary bile duct ligation. Results of preoperative evaluation of the ducts, operative treatment, and postoperative results were analyzed. A total of 413 patients were included. Forty-five patients presented with complete obstruction. In 15 cases, the ligature was intentional, and in 30 cases, occlusion was involuntary. Bile duct dilation (>10 mm) was demonstrated in one case of voluntary (6%) and three cases of involuntary ligations (10%). The remaining cases in both groups had no duct dilation and developed necrosis at the blinded duct and leakage proximal to the ligature, with different degrees of bilioperitoneum and/or biloma. In all cases, a Roux-en-Y hepatojejunostomy was performed. Bile duct ligature produces dilation in a very small number of patients (less than 10%) and usually produces necrosis of the blinded stump with subsequent bile leakage. Placement of a subhepatic drain and transference of the patient to a qualified center for reconstruction is the best approach if the primary surgeon is not able to do the repair.
    Journal of Gastrointestinal Surgery 06/2008; 12(6):1029-32. · 2.39 Impact Factor
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    ABSTRACT: To analyze data in a single institution series of pancreaticoduodenectomies (PD) performed in a 7-year period after the transition to a high-volume center for pancreatic surgery. PD has developed dramatically in the last century. Mortality is minimal yet complications are still frequent (around 40%). There are very few reports of PD in Latin America. Data on all PDs performed by a single surgeon from March 2000 to July 2006 in our institution were collected prospectively. During the study's time frame 122 PDs were performed; 84% were classical resections. Mean age was 57.9 years. Of the patients, 51% were female. Intraoperative mean values included blood loss 881 ml, operative time 5 h and 35 min, and vein resection in 14 cases. Both ampullary and pancreatic cancer accounted for 34% of cases (42 patients each), 5.7% were distal bile duct and 4% duodenal carcinomas. Benign pathology included chronic pancreatitis, neuroendocrine tumors, cystic lesions, and other miscellaneous tumors. Overall operative mortality was 6.5% in the 7-year period, 2.2% in the later 5 years. There was a total of 75 consecutive PDs without mortality. Of the patients, 41.8% had one or more complications. Mean survival for pancreatic cancer was 22.6 months and ampullary adenocarcinoma was 31.4 months. To our knowledge, this is the largest single surgeon series of PD performed in Latin America. It emphasizes the importance of experience and expertise at high-volume centers in developing countries.
    Journal of Gastrointestinal Surgery 04/2008; 12(3):527-33. · 2.39 Impact Factor
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    ABSTRACT: The frequency of bile duct injuries associated to cholecystectomy remains constant (0.3-0.6%). A multidisciplinary approach (endoscopical, radiological, and surgical) is necessary to optimize the outcome of the patient. Surgery is indicated when complete section of the duct is identified (Strasberg's E injuries) requiring a bilioenteric anastomosis as treatment. Nowadays, the most frequent technique used for reconstruction is a Roux-en-Y hepatojejunostomy. Long-term results of reconstruction are related to several technical and anatomic factors, but an ischemic duct (with subsequent scarring) plays a mayor role. In this paper, we report the results of biliary reconstructions comparing the extrahepatic-probably ischemic -- to intrahepatic -- non ischemic -- repairs. We reviewed the files of patients referred to our hospital (third-level teaching hospital) for bile duct repair after iatrogenic injury from 1990 to July 2006. Injury classification, time lapse since injury, surgical repair technique, and long-term follow-up were noted. In all cases, a Roux-en-Y hepatojejunostomy was done. Partial resection of segment IV was performed in 136 patients to obtain noninflamed, nonscarred, nonischemic biliary ducts with the purpose of reaching the confluence and achieving a high-quality bilioenteric anastomosis. An anastomosis at the level of the confluence was attempted in 293 patients (in 198 the confluence was preserved and in 95 it was lost). In the remaining 80 patients, a low bilioenteric anastomosis was done at the level of the common hepatic duct. We compared intrahepatic (198) and extrahepatic (80) repairs. A total of 405 cases (88 males, 317 females) were identified, with a mean age of 42 years (range 17-75). All of the injuries were classified as Strasberg E1, E2, E3, E5 (less frequent); those with E4 classification (separated ducts) were excluded. In all cases, the confluence was preserved (N = 293). Thirty-two cases were repaired minutes to hours after the injury occurred. The remaining 373 patients arrived weeks after the injury. In 198 cases, an intrahepatic repair was done, including the 136 in which resection of segments IV and V was part of the surgery. In the remaining 80 cases (operated between 1990 and 1997), an extrahepatic repair was done at the level of the common hepatic duct where the surgeon found a healthy duct. Twelve (15%) of the 80 cases with extrahepatic anastomosis required a new intervention (surgical or radiological), compared to only 8 of the 198 (3%) that had an intrahepatic anastomosis (P = 0.00062). Good results were obtained in 85% and 97% of the cases with extrahepatic anastomosis and intrahepatic anastomosis, respectively. Both groups had a reintervention rate of 7% (20/278). An intrahepatic anastomosis requires finding nonscarred, nonischemic ducts, thus allowing a safe and high-quality anastomosis with significantly better results when compared to the low-level anastomosis group.
    Journal of Gastrointestinal Surgery 03/2008; 12(2):364-8. · 2.39 Impact Factor
  • Carlos Chan, Ismael Domínguez
    Revista de gastroenterologia de Mexico 09/2006; 71 Suppl 1:42-6.
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    ABSTRACT: A variant of bilioenteric anastomosis, laterolateral hepatojejunostomy, is described in which the opened anterior aspect of the common hepatic duct and left hepatic duct is anastomosed to a Roux jejunal limb. This technique is specially designed for thin, injured bile ducts in which a conventional anastomosis is difficult due to the small diameter of the ducts. A wide anastomosis is obtained, leaving the posterior wall as a conduit for bile, ensuring an adequate anastomotic diameter.
    Journal of Gastrointestinal Surgery 09/2006; 10(8):1164-9. · 2.39 Impact Factor
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    ABSTRACT: Roux-en-Y hepatojejunostomy is the procedure of choice for biliary reconstruction after complex iatrogenic injury that is usually associated with vascular injuries and concomitant ischemia of the ducts. To avoid the ischemic component, our group routinely performs a high repair to assure an anastomosis in noninflamed, nonscarred, and nonischemic ducts. If the duct bifurcation is preserved, the Hepp-Couinaud approach for reconstruction is an excellent choice. Partial liver resection of segments IV and V allows adequate exposure of the bile duct at its bifurcation with an anterior approach of the ducts (therefore not jeopardizing the circulation), allowing a high quality anastomosis. Long-term results of bile duct reconstruction using this approach are described. Two hundred eighty-five bile duct reconstructions were done between 1989 and 2004 in a tertiary care university hospital. The first partial-segment IV resection was done in 1994; 94 cases have been reconstructed since then using this approach. All of them had a complex injury (Strasberg E1-E5), and although in many cases the bifurcation was preserved (E1-E3), a high bilioenteric anastomosis was done to facilitate the reconstruction. In 70 cases, the bifurcation was identified, and in the 24 in which the confluence was not preserved, the right and left ducts were found except in one case. In three patients, the right duct was found unsuitable for anastomosis, and a liver resection was done. In the remaining 21, an anastomosis was done using a stent (transhepatic, transanastomotic) through the right duct. According to Lillemoe's criteria, 86 cases had good results (91%). In four of the eight remaining patients, there was the need to operate again due to the presence of an obstruction and/or cholangitis. In the rest, radiological instrumentation was done. Four of these cases have developed secondary biliary cirrhosis, two of which have died while waiting for a liver transplant, four and six years after reconstruction. Partial segments IV and V resection allows adequate exposure of the confluence and the isolated left or right hepatic ducts. Anterior exposure of the ducts allows an anastomosis in well-preserved, nonischemic, nonscarred, or noninflamed ducts. Parenchyma removal also allows the free placement of the jejunal limb, without external compression and tension, obtaining a high quality anastomosis with excellent long-term results.
    Journal of Gastrointestinal Surgery 02/2006; 10(1):77-82. · 2.39 Impact Factor
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    ABSTRACT: Analyze the experience with pancreaticoduodenectomy (PD) at the INCMNSZ. PD has become a popular procedure in hospitals throughout the USA and Europe in the last 25 years, where mortality is < 5% y morbidity remains around 40%. Nonetheless there are very few reports on PD in Latin America. The data of all PD's performed at the INCMNSZ between 1999 and 2005 was gathered prospectively and analyzed retrospectively. 133 PDs where performed; 47.5% where men and 52.5% where women. Median of age was 57.7 years. 81.5% underwent classical resection and 18.5% a pylorus preserving procedure. Intraoperative variables include: blood loss: 940 mL. (1,000). transfusion requirements: 1.9 U, median operative time: 5:49 (+/- 1:02) and median hospital stay: 14 days. Most frequent diagnosis include ampulary adenocarcinoma and pancreatic cancer Mortality in the entire series was 9.2%, decreased to 2.7% in the 2002-2005 period and from April 2003 has remained in 0. A total of 14 portal-superior mesenteric vein resections where performed. To our knowledge this is the largest series of PD in Latin America. Popularity and indications for PD are expanding. Mortality is acceptable and morbidity remains high despite much effort. This procedure is performed with a satisfactory outcome in high volume centers. Involvement of the portal-superior mesenteric vein is not a contraindication of PD.
    Revista de gastroenterologia de Mexico 01/2006; 71(3):252-6.
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    ABSTRACT: Liver transplantation (LT) is probably the biggest surgical aggression that a patient can endure. It was considered only as a last option in the era of experimental LT, yet it evolved into the definitive treatment for some types of acute and chronic end stage liver disease. In terms of technique LT is the most complex of all types of transplantations. The surgical procedure in itself is well established and has changed little through time. Liver transplantation owes its improvement to better and more systematic anesthetic procedures and to perioperative care more than being due to improvement of the surgical technique. The first surgical procedure was described by Thomas Starzl in 1969. His initial work has been strengthened with the development of venous bypass, the refinement in vascular and biliary reconstruction technique and the development of the split liver. Up to date technical aspects of orthotopic liver transplantation are described in the present article.
    Revista de investigacion clinica; organo del Hospital de Enfermedades de la Nutricion 04/2005; 57(2):262-272. · 0.31 Impact Factor
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    ABSTRACT: Cystic disease of the biliary tract (CDBT) is characterized by varying degrees of dilatation of the biliary system with high morbidity and mortality in which the surgical management is the corner stone of treatment. The cyst-enterostomies (CE) temporarily solve the obstruction to the biliary flow but have a high long-term morbidity. Complete resection of affected bile ducts with Roux-en-Y derivation (CRR-en-Y) is a good procedure with low mortality and complications. The purpose of the study was to analyze the outcome of CRR-en-Y versus CE in the treatment of CDBS in adult patients from 1970 to 2002. Patients who underwent surgical treatment were divided for their analysis into two groups: Group I: CRR-en-Y and Group II: CE. Following features were compared: demography, clinical picture, postoperative morbimortality, outcome and survival. Thirty-four adult patients were analyzed. There were 82% (28) females and 18% (6) males. The age average was 33.58 years (13-84). Seventy percent (30) were "choledochal cyst". Eighty percent (27) were surgically handled: 52% (14) with CRR-en-Y (Group I) versus 58% (13) with CE (Group II). Both groups were comparable. Without operative mortality and low postoperative morbidity in both, CE had more long-term complications: In this group 70% (9) were readmitted: and 7 underwent reoperation. Mean follow-up was 35 months (6-132) versus 152 months (12-408) respectively. CRR-en-Y is the standard treatment of CDBS in the adult patient.
    Hepato-gastroenterology 01/2005; 52(61):13-6. · 0.91 Impact Factor
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    ABSTRACT: Bile duct injuries have a frequency of 0.1% to 0.3% even in the most experienced centers. Complex biliary lesions usually require a bilioenteric anastomosis, achieving good long-term results in 80% to 90% of the cases. Besides injuries to the abdominal contents during laparoscopy (by trocars or electrocautery), intestinal complications associated with reconstruction attempts can be observed. We analyzed the concomitant intestinal complications in 251 patients with iatrogenic biliary injuries reconstructed over this 12-year period. A retrospective review of patients with biliary tract reconstruction after iatrogenic injury in a tertiary academic health-care center was done. All patients with concomitant intestinal injury were included; type of operation and postoperative outcome were analyzed. Among 251 patients, 35 cases had a concomitant intestinal injury. The most common site of fistulization was the duodenum (18 cases, 50%); 9 cases were associated with long-term subhepatic drains (more than three weeks), and the other 9 cases were associated with a dehiscent hepatoduodenostomy. Faulty Roux-en-Y reconstruction was observed in 5 cases. In 5 cases, fistulization of the jejunum and ileum, secondary to drain placement, was documented, as well as 3 cases with colonic injuries. Two patients had a dehisced Roux-en-Y anastomosis. One had a bilioenteric omega type ileal anastomosis, and 1 had a hepatoileal anastomosis without omega reconstruction. Primary repair of the duodenum with resection of the affected intestinal or colonic segment was done at the same time of biliary repair without related morbidity. Concomitant gastrointestinal injures were found with an incidence of 15% in our series. The most common site of fistulization is the duodenum. In half of the patients, it was secondary to a dehiscent hepatoduodenostomy, whereas in the other, it was caused by long-term subhepatic drains. Besides faulty Roux-en-Y reconstruction, fistulization was related with long-term drains. Primary repair and resection of the affected segment of jejunum, ileum, and colon can be done during the same operative stage of biliary reconstruction, without significant correlated mortality.
    Current Surgery 07/2004; 61(4):380-5.
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    ABSTRACT: Standard pancreatic resections, either proximal or distal ones, result in a considerable loss of pancreatic parenchyma and may cause impairment of the exocrine and endocrine functions. Central pancreatectomy has been indicated for small benign lesions located in the neck or body of the pancreas. It has the potential advantage of lowering the risk of functional impairment of the pancreatic parenchyma, biliary tract, upper gastrointestinal tract, and spleen. We present three cases of patients with benign, isolated pancreatic tumors who underwent a successful central pancreatectomy. From this small series, we believe that central pancreatectomy is an excellent therapeutic option for benign, localized pancreatic tumors.
    The American surgeon 05/2004; 70(4):304-6. · 0.92 Impact Factor
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    ABSTRACT: Non-cirrhotic portal hypertension has a better prognosis than other forms of portal hypertension because of a well-preserved liver function in most cases. These patients are good candidates to receive surgical treatment, which is the therapeutic choice available with the lowest rebleeding rate. Because of abnormalities in the splanchnic vessels due to the nature of the diseases, many of them cannot be shunted. An extensive esophagogastric devascularization, the complete portoazygos disconnection, was evaluated. A retrospective review of files of 31 patients, among 491 operations between 1991 an 2001 was carried out in a tertiary care Academic University Hospital. Patients comprised those with non-cirrhotic bleeding portal hypertension treated by means of complete portoazygos disconnection. Extensive two-stage (thoracic and abdominal) esophagogastric devascularization with modified transection of the esophagus was performed. Main outcome measures: recurrence of hemorrhage, encephalopathy and survival. Thirty-one patients were treated. In 17 cases (54%) a hypercoagulable state was demonstrated. No operative mortality was observed (0-30 days) with a total of 62 operations (two stages per patient). No case of encephalopathy was observed and in 3 cases (9%) rebleeding was recorded. The survival curve showed a 5-year survival of 97% and a 10-year survival of 93%. Complete portoazygos disconnection is an excellent surgical alternative for patients with non-cirrhotic portal hypertension, with a low morbidity and mortality as well as a low rebleeding rate and good long-term survival.
    Hepato-gastroenterology 01/2004; 51(60):1757-60. · 0.91 Impact Factor
  • Journal of Gastrointestinal Surgery 02/2003; 7(2):283–284. · 2.36 Impact Factor
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    ABSTRACT: INTRODUCCIÓN: Los tumores de vías biliares son tumoresraros que tienen una incidencia de 1 en 100, 000 habitantes.En un paciente con este tipo de tumor la cirugía puede sercurativa en etapas tempranas, con una supervivencia a 5años de 20%, los pacientes con enfermedad avanzada tienenuna supervivencia de 6 a 7 meses y en ellos están indicadoslos procedimientos paliativos.OBJETIVO: Mostrar la experiencia en un período de 14 añosen pacientes con tumores de vías biliares y que recibieronalgún tratamiento quirúrgico con intento curativo o paliativo.METODOLOGÍA: Se trata de un estudio metodológicamentediseñado como serie de casos, con 23 pacientes operadosen un período de 14 años, de 1987 a 2001.RESULTADOS: La colangitis fue el principal motivo deconsulta en 55% (13) de los pacientes, al ingreso se observóictericia y malestar generalizado en 95% de los pacientes, eldolor y el prurito fueron la segunda manifestación en el77%. La sensibilidad diagnóstica del ultrasonido y latomografía fue mayor al 50%. Las lesiones Bismuth II fueronlas más frecuentes en 39%. Se realizó Hepato-yeyunoanastomosis en el 59%, de los cuales se colocó sonda en Ten el 77% de los pacientes. Otras alternativas utilizadasfueron hepatectomía derecha o izquierda y procedimientode Whipple. En 4 casos sólo se realizó derivación con sondaT o la colocación percutánea de sonda transhepática.El adenocarcinoma no papilar fue la variedad histológicamás frecuente, los estadios avanzados T4 se observaron enun 50% y sólo el 32% tenían un estadio T2. El promedio desupervivencia fue de 7.5 meses (intervalo 0.07 a 22.2).CONCLUSIONES: Los tumores de vías biliares son unaenfermedad poco frecuente, el mayor número de casos sepresentan en etapas avanzadas cuando la cirugía ya noofrece la posibilidad de curación, por tanto, las alternativasquirúrgicas paliativas son de elección para mejorar lacalidad de vida.
    Salud en Tabasco. 01/2003;
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    ABSTRACT: The diagnosis of pancreatic cancer continues to produce fear in both patients and practitioners in large part owing to the likely incurability in all for whom the diagnosis is made. It is this reality that continually motivates the surgical and medical oncologists who endeavor to treat these patients. Currently, the cure rate for pancreatic cancer has improved only minimally, and the overall survival of patients remains dismal, with fewer than 5% of patients alive at 5 years and 92% of these patients dead at 2 years. This current treatment status has stimulated numerous studies endeavoring to understand the diverse mechanisms of cell growth in this tumor. Intensive investigative efforts have produced the understanding of new tumor suppressor genes such as DPC4 and an increasing understanding of tyrosine kinase receptors and signal transduction and their regulation of programmed cell death (apoptosis). Detection of these numerous genetic defects may give new insights and understanding of the highly chemo- and radioresistant nature of pancreatic cancer. These same findings also provide the basis for the development of new potential therapies for pancreatic cancer through gene therapy. This paper reviews the significant molecular biologic findings and their influence on the development of gene therapy strategies in the treatment of pancreatic adenocarcinoma.
    World Journal of Surgery 08/2002; 26(7):854-60. · 2.35 Impact Factor
  • Journal of Hepatology 04/2002; 36:252-253. · 10.40 Impact Factor