[Evaluation of the sentinel lymph node in T1-T2 papillary thyroid cancer: a preliminary study]. / Valoración del ganglio centinela en el cáncer papilar de tiroides T1-T2. Estudio preliminar.

OBJECTIVE: Sentinel lymph node biopsy in differentiated thyroid cancer may benefit patients with no clinically affected lymph nodes and can avoid a prophylactic or staging lymphadenectomy. METHODS: A prospective study was conducted on 23 consecutive patients with papillary thyroid carcinoma with no clinical or radiological suspicion of lymph involvement. After injecting methylene blue around the tumour during the biopsy of the identified sentinel lymph node, a total thyroidectomy and a via-b ipsilateral lymphadenectomy was performed for the later study with cytokeratin. If the sentinel lymph node was positive, a modified ipsilateral radical lymphadenectomy was perfumed (groups ii to v). RESULTS: The sentinel lymph node was clearly identified in 21 of the 23 patients (91.3%). Seven (33%) of the 21 lymph nodes identified were positive in the intra-operative study, of which 3 (42.8%) demonstrated involvement with the lateral compartment. All together, 9 patients (39.1%) showed lymph node involvement group vi, with two more patients being identified with micro-metastases in the later study. Biopsy of the sentinel lymph node had a sensitivity of 87.5%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 93.7%, with 7.1% false negatives. Five patients (21.7%) had transient hypocalcaemia. CONCLUSIONS: The identification of the sentinel lymph node in patients with T1-T2 tumours with no suspicion of lymph node involvement helps in the selection of patients who should be treated with selective lymphadenectomies.

Larrad biliopancreatic diversion in Sprague-Dawley rats. Analysis of weight loss related to food intake.

BACKGROUND: Existing medical therapeutic strategies to achieve and maintain clinically significant weight loss in morbid obesity remain limited and the biliopancreatic diversion (BPD) is still the most effective among the bariatric surgical procedures. Our objective was to evaluate the weight and food intake after this procedure in a rat model. METHODS: Rats randomly underwent one of the following protocols (1) BPD (n = 12) versus sham (n = 12) with a follow-up period of 30 days and (2) BPD (n = 4) versus pair-fed (PF; n = 4) with a follow-up period of 50 days. Under intraperitoneal anesthesia with ketamine-xilacine, a subcardinal corpo-antral gastrectomy was made, preserving the gastric fundus that was anastomosed to a jejunal limb after dissecting the proximal jejunum 5 cm below the ligament of Treitz to form the alimentary limb. The biliopancreatic limb was terminolaterally anastomosed to the distal ileum 5 cm above the ileocecal valve to form the common limb. Sham animals underwent only abdominal incision. Weight and food intake were measured every day. RESULTS: In protocol 1, after postoperative day 30, BPD rats exhibited a mean weight reduction of 17.9% while shams increased 12.4%. There was no difference in food intake adjusted per 100 g of body weight. In protocol 2, after postoperative day 50, BPD rats had a mean weight reduction of 22.6% and, despite increasing their caloric intake from a mean of 42.6 after 6 days to 65.8 kcal/day after 50 days, they kept a similar mean weight of 344.0 and 340.2 g, respectively; on the contrary, PF rats exhibited a 30.8% body weight gain. CONCLUSIONS: After the BPD, body weight is maintained independently of changes in food and energy intake.

Short-, mid- and long-term results of Larrad biliopancreatic diversion.

BACKGROUND: In an effort to reduce the complications of Scopinaro's biliopancreatic diversion (BPD), in 1989 we introduced the modification of lengthening the alimentary channel preserving most of the jejunum-ileum, by creating a short biliopancreatic limb (50 cm) and maintaining 50 cm of common limb (Larrad 50-50 BPD). METHODS: Of 343 patients who consecutively underwent Larrad 50-50 BPD surgery, 325, 194 and 65 patients were evaluated at 2, 5 and 10 years after surgery, respectively, in terms of surgical morbidity, mortality, metabolic sequelae and weight. Mean age was 41.2 years (range 17-62), mean initial weight 151.2 kg (range 97-260), and BMI was 52.2 kg/m2. Maximum follow-up was 120 months. RESULTS: Mortality was 0.87% and surgical morbidity 7.6%. There were no cases of suture dehiscence, peritonitis or stomal stenosis. Percent excess weight loss (%EWL) stabilized 2 years after surgery and at 10 years was 77.8 +/- 11.2% for morbidly obese patients and 63.2 +/- 11.8% for super-obese patients. The main complications were 43.8% clinical incisional hernia, 2.5% severe diarrhea, 10.8% mild diarrhea and 9.2% constipation. 30% experienced anemia and/or iron deficiency, and 3% required iron parenterally or lifelong zinc supplements. 28% showed preoperative PTH elevation and 30% vitamin D deficiency; these values postoperatively increased to 45% and 43% respectively. Both these alterations were resolved using supplements, although 12% needed increased doses of vitamin D. The incidence of severe hypoproteinemia was 0.29%. No patient required surgical reversal. When independently evaluated, failure rates in terms of insufficient weight loss were 9% at 5 years and 11.3% at 10 years for morbidly obese, and 12.2% and 14% for super-obese patients respectively. According to the BAROS questionnaire, 75% of surgery outcomes were excellent or very good, 18% good, 5% fair and 2% failures. CONCLUSIONS: After 2, 5 and 10 years, Larrad's BPD has offered excellent results in terms of weight loss and quality of life, a low rate of metabolic sequelae, including a hypoproteinemia rate < 0.5%, and a revision surgery rate 0%.

Analysis of weight loss with the biliopancreatic diversion of Larrad: absolute failures or relative successes?

BACKGROUND: The authors studied whether morbidly obese patients who failed in stated weight loss criteria may be considered absolute failures or relative successes. METHODS: 75 morbidly obese patients underwent biliopancreatic diversion (BPD) of Larrad, with a 4/5 gastrectomy (residual gastric volume 150-200 ml), a biliopancreatic limb divided 50 cm distal to Treitz' ligament, a 50-cm common limb and an alimentary limb of nearly all the bowel length (500-600 cm). Every patient had a follow-up of 5 years. A percent excess weight loss (%EWL) < 50% was considered a "failure". We analyzed the post-surgical changes in the preoperative obesity-related problems in these patients and the causes of the weight loss failure. RESULTS: At 5 years after the BPD of Larrad, 9 patients (12%) had a %EWL < 50%, with a mean %EWL of 36 in these patients. Most of these failed patients were cured or improved of their preoperative illnesses. The 2 males were alcoholics, and 6 of the 7 females had an abnormal psychological examination. Comparing the "failed" patients with the successful group, there is a statistically significant influence (p < 0.01) of lack of satiety, unmarried status, housewife or unemployed. CONCLUSION: Patients judged as a failure by weight loss criteria after bariatric surgery should not be considered absolute failures, because most of their preoperative illnesses were cured or improved, improving their quality of life. Thus, they are "relative successes".

Course of metabolic syndrome following the biliopancreatic diversion of Larrad.

BACKGROUND: The authors assessed the effect of Larrad's biliopancreatic diversion (BPD) on the main components of the metabolic syndrome. PATIENTS AND METHODS: Plasma concentrations of glucose, insulin, total cholesterol (TC), HDL and LDL cholesterol, triglycerides, LDL/HDL and TC/HDL ratios, and blood pressure and body weight were retrospectively evaluated in 40 patients 3-6, 12, 24 and 60 months after undergoing BPD for morbid obesity with metabolic syndrome. RESULTS: 3-6 months after BPD, glycemia and insulinemia had normalized in 97.5% of the patients and remained stable over the following 5 years. Over this period of 3-6 months to 5 years following BPD, total and LDL cholesterol levels fell by 45.2% and 53.1%, respectively. From 12 months onwards, triglyceride levels decreased appreciably, dropping by 57.4% at 5 years. HDL cholesterol concentrations failed to vary significantly or increased to normal levels in patients showing low initial values. At 5 years, high blood pressure had resolved in 75% of patients and the amount of excess weight lost was 65.5% (+/-14.6). No patient required reversal of the BPD due to severe gastrointestinal or metabolic complications. CONCLUSIONS: Technically adapted to the patient's weight, the Larrad BPD effectively stabilizes the main components of the metabolic syndrome. The BPD has low morbidity rate and should be considered a therapeutic option for patients who do not respond to medical treatment.

Biliopancreatic diversion induces villi elongation and cholecystokinin and ghrelin increase.

INTRODUCTION: Factors leading to weight loss and weight stabilization after bariatric surgery are not fully understood. Our aim was to evaluate, in Sprague-Dawley rats, the histological and gut hormonal changes after Larrad-biliopancreatic diversion (Larrad-BPD). MATERIALS AND METHODS: Rats randomly underwent the following protocols: Larrad-BPD (n=4) versus pair fed (PF) (n=4). Weight and food intake were measured every day. By immunohistochemistry ghrelin was examined in the stomach, while cholecystokinin (CCK), glucagon-like-peptide-1 (GLP-1), peptide YY (PYY) and serotonin (5-HT) expression were analyzed in alimentary limb and ileum following or not the Larrad-BPD. RESULTS: Larrad-BPD rats exhibited significant (P<0.05) weight loss compared to PF rats. Villi enlongation was observed in Larrad-BPD rats. In residual stomach, ghrelin was diminished. In the alimentary limb, ghrelin and CCK positive cells were detected more than in the ileum of PF rats. GLP-1 expression was decreased and PYY expression was absent after Larrad-BPD compared with PF rats. DISCUSSION: Larrad-BPD is followed by histological changes and a pleiotropic gut endocrine response aimed to compensate the reduction of intestinal area exposed to food. Until now, the hormones responsible for the intestinal hypertrophy have not been defined.

[Larrad biliopancreatic diversion. Description of an rat experimental model]. / Derivación biliopancreática de Larrad. Descripción de un modelo experimental en la rata.

UNLABELLED: OBJECTIVE.: To validate the experimental model of Larrad-biliopancreatic diversion (LBPD) and to analyze weight gain and mortality in rats fed with non- supplemented diets. MATERIAL AND METHOD: Control (6) and experimental (10) male Wistar rats were used. The experimental group was operated on using the human LBPD adapted for rats: Subcardial gastrectomy, a short biliopancreatic channel created at 5 cm from Treitz angle and common channel at 5 cm from ileocecal valve. After surgery recovery (7 days) the rats were fed ab libitum with a standard non-supplemented diet (without proteins, minerals or vitamins). Percentage of weight lost or gained up to the end of the experiment was analyzed. RESULTS: The control animals gained weight progressively from 13.1 +/- 2.4% at day 7 to 58 +/- 9.2% at day 63, when the animals were sacrificed. After LBPD, mortality was 50% at day 25 +/- 17.5(range, 14-56), no significant differences in the percentage of weight lost being found between surviving (-38.9 +/- 14.2%) and non-surviving rats (-29 +/- 5.6%; p = 0.192). Of the surviving animals, 80% progressively lost weight reaching a maximum loss between day 63 (-42.3 +/- 8%) and 70 (-44.1 +/- 9.7%), and 20% lost weight until day 35 and gained over 7% of body weight until sacrifice (day 147). CONCLUSIONS: An experimental model of LBPD in rats is technically feasible. Both mortality and percentage weight loss are not directly related. The bowel adaptation mechanism could mediate the percentage of weight regain in operated rats.