Can 3D-printed patient-specific instruments improve local control and overall survival in pelvic sarcoma? A clinical validation study. / Guías impresas en 3D: ¿mejoran el control local y la supervivencia global en el tratamiento de los sarcomas pélvicos? Estudio de validación clínica.

BACKGROUND AND OBJECTIVES: 3D-printed patient-specific instruments (PSIs), also known as 3D guides, have been shown to improve accuracy in resection of pelvic tumors in cadaver studies and achieve better surgical margins in vivo. This study evaluates the clinical impact of 3D-printed guides on medium-term local and distant disease control, as well as disease-free and overall survival in patients. MATERIAL AND METHODS: A cohort study included 25 patients with primary pelvic or sacral sarcomas: 10 in the 3D group and 15 in the control group, with a median follow-up of 47 months. Demographic and clinical data, including tumor histology, stage, resection technique, associated reconstruction, adjuvant therapies, and complications, were evaluated. Surgical margins (free, marginal, and contaminated) and relapse-free and overall survival curves were analyzed. RESULTS: The 3D group achieved a higher rate of free margins (80% vs 66.7%, p = 0.345). Local recurrence (50% vs 60%, P=.244) and distant disease relapse (20% vs 47%, p = 0.132) rates were lower in the 3D group. At the end of the follow-up, the 3D group had a higher overall survival rate (60% vs 40%, p = 0.327). The complication rate was similar in both groups, with a deep infection rate of 40%. CONCLUSIONS: The use of 3D guides in resecting primary pelvic tumors not only achieves a higher rate of free margins compared to conventional techniques but also shows a trend towards higher local, distant, and overall disease-free survival. Further studies with larger sample sizes and higher levels of evidence are necessary to validate these clinical trends.

Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery. / Validación de los modelos de impresión 3D paciente-específicos para cirugía ortopédica oncológica pélvica.

INTRODUCTION: Pelvic ring tumors pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. MATERIAL AND METHODS: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. RESULTS: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis (5-8mm), being conditioned by the position of the rigid body. CONCLUSION: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.

[Translated article] Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery.

INTRODUCTION: Pelvic ring tumours pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. MATERIAL AND METHODS: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. RESULTS: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis (5-8mm), being conditioned by the position of the rigid body. CONCLUSION: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.

Prognostic value of (13)C-phenylalanine breath test on predicting survival in patients with chronic liver failure.

AIM: To evaluate the prognostic value of percentage of (13)C-phenylalanine oxidation ((13)C-PheOx) obtained by (13)C-phenylalanine breath test ((13)C-PheBT) on the survival of patients with chronic liver failure. METHODS: The hepatic function was determined by standard liver blood tests and the percentage of (13)C-PheOx in 118 chronic liver failure patients. The follow-up period was of 64 mo. Survival analysis was performed by the Kaplan-Meier method and variables that were significant (P < 0.10) in univariate analysis and subsequently introduced in a multivariate analysis according to the hazard model proposed by Cox. RESULTS: Forty-one patients died due to progressive liver failure during the follow-up period. The probability of survival at 12, 24, 36, 48 and 64 mo was 0.88, 0.78, 0.66, 0.57 and 0.19, respectively. Multivariate analysis demonstrated that Child-Pugh classes, age, creatinine and the percentage of (13)C-PheOx (HR 0.338, 95% CI: 0.150-0.762, P = 0.009) were independent predictors of survival. When Child-Pugh classes were replaced by all the parameters of the score, only albumin, bilirubin, creatinine, age and the percentage of (13)C-PheOx (HR 0.449, 95% CI: 0.206-0.979, P = 0.034) were found to be independent predictors of survival. CONCLUSION: Percentage of (13)C-PheOx obtained by (13)C-PheBT is a strong predictor of survival in patients with chronic liver disease.

[Hemipelvectomy for the treatment of high-grade sarcomas: Pronostic of chondrosarcomas compared to other histological types]. / Hemipelvectomías tras sarcomas de localización pélvica de alto grado: pronóstico en condrosarcomas frente a otros tipos histológicos.

INTRODUCTION: The low incidence and histological heterogeneity of primary sarcomas located in the pelvis makes it difficult to find homogeneous cohorts. OBJECTIVE: To describe the life and functional prognosis depending on the histological type of sarcoma in a series of locally advanced high-grade pelvis located sarcomas treated by hemipelvectomy. METHODS: A descriptive epidemiological and functional study was conducted on 15 cases treated between 2006 and 2012. Survival analysis, functional assessment, and a comparative study by histological type were performed, comparing chondrosarcomas to other histological diagnoses. RESULTS: The most frequent histological type was chondrosarcoma (46%), and the most frequent location was P2 (periacetabular) (73%). An internal hemipelvectomy was performed in 66% of cases, with a higher incidence (83%) in chondrosarcomas. Overall two-year survival was 54%, with higher survival in the chondrosarcoma group (67%) than in the other sarcomas (43%). Functional status depended on the type of intervention, with no differences in histological type or the performance of the reconstruction. DISCUSSION AND CONCLUSIONS: Hemipelvectomy is a surgical procedure that is indicated for the treatment of locally advanced high grade pelvis located sarcomas, regardless of histological type. The incidence of limb preservation and overall survival is higher in chondrosarcomas compared to other sarcomas.

Rôle of psychosomatic factors in peptic ulcer disease.

Evidence indicates that a link between peptic ulcer disease (PUD) and selected psychosomatic factors may exist. A series of 70 consecutive male and female adult patients were categorized by peptic symptoms and divided into four groups: a) controls; b) gastric ulcer (GU); c) duodenal ulcer (DU); and d) chronic non-ulcer dyspepsia (CNUD). All patients were interviewed and asked to answer a questionnaire that included demographics, medical history and the incidence of negative life events. A decreased level of activity was a predominant finding in GU, DU and CNUD patients. Family history of PUD may be correlated with CNUD. Of interest was the finding that DU and CNUD patients presented a higher incidence of negative life events when compared to the other study groups. Negative life events that produce considerable stress may predispose to peptic symptoms in certain patients.

Comparison of Three 7-Day Pantoprazole-Based Helicobacter pylori Eradication Regimens in a Mexican Population with High Metronidazole Resistance.

OBJECTIVE: To compare the efficacy and tolerability of three 7-day pantoprazole-based regimens to eradicate Helicobacter pylori in Mexican patients with peptic ulcer (PU) or non-ulcer dyspepsia (NUD). BACKGROUND: Short-term therapeutic regimens based on a proton pump inhibitor (PPI) and two antibiotics have been recommended for the eradication of H. pylori. Resistance of H. pylori to metronidazole may adversely affect the efficacy of such regimens. PATIENTS AND METHODS: This was a single-centre, randomised, open-label, parallel-group study in which three groups of H. pylori-positive patients with PU or NUD were compared (n = 159; intention-to-treat population). Patients were randomised to receive a 7-day pantoprazole-based triple therapy for eradication of H. pylori. Patients received pantoprazole (P) 40mg twice daily in combination with either i) amoxicillin (A) 1000mg twice daily and clarithromycin (C) 500mg three times daily (PAC regimen, n = 51 patients), or ii) clarithromycin 500mg three times daily and metronidazole (M) 500mg three times daily (PCM regimen, n = 55 patients), or iii) amoxicillin 1000mg twice daily and metronidazole 500mg three times daily (PAM regimen, n = 53 patients). After completing eradication therapy, all PU patients were further treated with once-daily pantoprazole 40mg, either for another 3 weeks (patients with duodenal ulcer) or for another 7 weeks (patients with gastric ulcer), to ensure complete ulcer healing. At baseline examination, all patients underwent the (14)C-urea breath test and endoscopy; biopsy specimens were taken for histology, CLO-test, H. pylori culture and antibiotic susceptibility testing (agar dilution E-test). Eradication of H. pylori was assessed after all treatment with pantoprazole had been discontinued for at least 4 weeks, using the (14)C-urea breath test. RESULTS: In the per-protocol population (n = 153), eradication was achieved in 81.3% (39/48) of patients receiving PAC, 66.0% (35/53) of PCM recipients, and 48.1 % (25/52) of those receiving PAM (p = 0.13 for PAC vs PCM and 0.001 for PAC vs PAM). In the intention-to-treat population, respective eradication rates were 76.5 (39/51), 63.6 (35/55) and 47.2% (25/53) [p = 0.22 for PAC vs PCM and 0.004 for PAC vs PAM]. Patient compliance was very good in all treatment groups. The main adverse event affecting 40% of all patients was a metallic taste, assessed as likely related to the antibiotics. Susceptibility to the three study antibiotics was determined for H. pylori isolates using the pretreatment biopsies from 103 patients. Resistance to metronidazole was present in 68.2% of patients and to clarithromycin in 24.3%. In 16.8% of patients, H. pylori isolates were resistant to both metronidazole and clarithromycin. In patient populations with H. pylori strains resistant to one or both of the antibiotics used in the respective treatment regimen, eradication rates were consistently lower than in those with susceptible H. pylori strains. However, these differences were not statistically significant, probably due to the small sample size. CONCLUSIONS: The 7-day H. pylori eradication regimen with PAC was superior to PCM and PAM. This is probably due to the high resistance rate to metronidazole in the Mexican population. Thus, H. pylori eradication regimens that involve metronidazole cannot be recommended for Mexican patients. RESULTS from this study highlight the regional differences in efficacy of some well established H. pylori eradication regimens, and suggest that culture and susceptibility testing to define H. pylori resistance patterns in specific geographical areas may be indicated before recommending any particular eradication schedule.

[Amylase test in the diagnosis of acute pancreatitis]. / La prueba de la depuración de amilasa en el diagnóstico de la pancreatitis aguda.

The determination of serum and urinary amylase are methods used in the diagnosis of acute pancreatitis, however there are many abdominal problems that can cause hyperamylasemia, in the absence of pancreatic disease, for this reason in 1969 Levitt and col. signaled the possible advantages of amylase/creatinine clearence ratio, in the clinical diagnosis of acute pancreatitis. This test was used in cases with acute pancreatitis, as in other diseases, in correlation with levels in normal subjects, with the objective of evaluating its clinica utility, in relation to the formentioned paragraph. Results concluded that the amylase/creatinine ratio is not of greater diagnostic utility than the determination of urinary amylase, in acute pancreatitis.

[Secondary sclerosing cholangitis. Radiologic diagnosis and anatomoclinical correlation. Report of a case]. / Colangitis esclerosante secundaria. Diagnóstico radiológico y correlación anatomoclínica. Presentación de un caso.

Radiological diagnosis of secondary sclerosing cholangits was made in a patient who presented changes in morphology of the biliary tree in two consecutive post-operatory T-tube cholangiograms. The main change was a diffuse narrowness of the intrahepatic branches. Anatomical changes in post mortem examination had a good correlation with radiological images. The importance of this entity and experience from other authors in the current literature are discussed.

[Primary sclerosing cholangitis. A report of 4 cases]. / Colangitis esclerosante primaria. Informe de cuatro casos.

We informed four cases of primary sclerosing cholangitis associated with chronic ulcerative colitis, diagnosed in the Gastroenterology Department, Hospital de Especialidades del CM Siglo XXI Mexico City, during 1987 to 1988. The mean age was 30.2 years and the evolution of colitis was 6.6 years. Two patients were females and two males, all presented active colitis and three presented hepatic symptoms. The laboratory abnormalities were hypertransaminasemia, increased alkaline phosphatase and hyperbilirubinemia. In three patients endoscopic retrograde cholangiopancreatography was done, in all cases diagnosis was established by histology. The frequency of primary sclerosing cholangitis associated with chronic ulcerative colitis was 13.3%.

[Percutaneus cholangiography with the Chiba needle. Results in 220 studies]. / Colangiografía percutánea con aguja de Chiba. Resultados en 220 estudios.

The authors employed this new technique of thin needle percutaneous cholangiography in 220 patients with the following results: 99.3% (146/147) success with previous biliary tract dilatation and 79.4% (53/73) success in patients with normal caliber bile ducts. The overall result of 92.7% (204/228) emphasizes that radiological opacification is the best way to study the icteric patient. Only 1.8% of patients with serious complications is less than in other instrumentation methods. By not requiring specialized equipment and being accessible in the majority of hospitals, study cost is reduced. In conclusion, this new technique of percutaneous cholangiography is preferable for accessibility, efficacy, cost and risk in the study of the icteric patient.

[Comparison of 2 schedules based on pantoprazole for eradication of Helicobacter pylori in patients with active duodenal ulcer]. / Comparación de dos esquemas basados en pantoprazol para erradicación de Helicobacter pylori en pacientes con úlcera duodenal activa.

OBJECTIVE: To compare the efficacy and tolerability of a triple vs dual pantoprazole based therapy to eradicate Helicobacter pylori (H. pylori) in mexican patients with florid duodenal ulcer. BACKGROUND: The treatment of peptic ulcer disease was revolutionized by the fact that H. pylori generally induces chronic gastritis and peptic ulcer disease and that the cure of the infection prevents ulcer relapses. MATERIAL AND METHODS: 74 H. pylori positive patients with florid duodenal ulcer were randomized to receive either pantoprazole 40 mg bid in combination with clarithromycin 500 mg tid and amoxicillin 1 g bid (triple regimen PAC) or pantoprazole in combination with clarithromycin and placebo (dual regimen PC) during 14 days. To ensure complete ulcer healing all patients received an additional 2 weeks treatment with pantoprazole 40 mg od. 14C Urea Breath test (UBT) was the main criteria used to determine eradication rate with < 150 disintegrations per minute (DPM) to consider a patient eradicated. In all patients culture, antibiotic susceptibility (E-test) and histology were performed. RESULTS: In the per protocol analysis (n = 66) the eradication rate was: PAC 93.5% vs PC 54.3% (p < 0.001). 76% of H. pylori strains were resistant to metronidazole. Tolerance and compliance were excellent in both groups. CONCLUSIONS: Triple therapy (PAC) was shown to be superior to dual therapy (PC) for H. pylori eradication in mexican patients with florid duodenal ulcer.

[Breath tests as a noninvasive diagnostic method in Helicobacter pylori infection]. / La prueba de aliento como método diagnóstico no invasivo en la infección por Helicobacter pylori.

There are several diagnostic methods for Helicobacter pylori infection, some of them need an endoscopic procedure and biopsy to be performed (invasive) like the rapid urease test, culture and histology. Recently non invasive, specific, sensible, easy to perform and patient's well accepted methods had been developed known as breath test, based on the hydrolysis of labelled urea by Helicobacter pylori urease enzyme, to release ammonia and bicarbonate. Labelled CO2 reaches the bloodstream and the lungs, from where can be collected into the breath for quantification. Labelled urea has to options: 13C stable, non-radioactive and 14C unstable, radioactive. Breath test with 13C is based on the atomic mass difference between 12C and 13C and it is necessary a mass spectrometer and 40 minutes to perform it. Breath test with 14C has 1 uCi (one micro-curie) of radioactivity (1/300 of total radiation received in one year from the environment); the test takes 10 minutes and the samples are read in a beta counter. Both non-invasive tests had demonstrated sensitivity and specificity comparable to established "gold standards" for Helicobacter pylori infection diagnosis.

[Prevalence of antinuclear antibodies in primary biliary cirrhosis, with negative antimitochondrial antibodies]. / Prevalencia de anticuerpos antinucleares en cirrosis biliar primaria, con anticuerpos antimitocondriales negativos.

Recently it has been described in the literature a subpopulation of PBC patients with negative AMA that might represent patients with ANA positive autoimmune cholangitis. We review 25 cases of PBC (23 females) with AMA negative. Our aim was to determine the frequency of ANA(+) in this group. We studied serum transaminases, total bilirubin, AMA and ANA by indirect immunofluorescence considering positive dilutions of 1:40. All patients had elevated alkaline phosphatase (641 +/- 389 U/l). Total bilirubin was below 2.5 in 59%. Thirteen patients had esophageal varices. The histologic stage was I-II in eleven and III-IV in 14 cases. Fourteen patients (56%) has ANA(+) (dilution 1:40), 44% had lower dilutions. We confirm the presence of a subpopulation of PBC AMA negative, ANA positive patients and the observations of different and diverse immune alterations in PBC patients.

[Effects of fiber administration in the prevention of gallstones in obese patients on a reducing diet. A clinical trial]. / Efecto de la administración de fibra en la prevención de litiasis vesicular en obesos sometidos a dieta de reducción. Ensayo.

Nearly 30% of the obese patients treated with hypoenergetic diets for weight reduction develop gallstone disease (GD). Until the present time, the use of ursodeoxycholic acid (UDA) is the only available therapeutic measure to avoid the development of GD. Dietary fiber induce a bile acid synthesis. A double-blind clinical trial was conducted to compare the effect of rational diet plus UDA vs a rational diet supplemented with Psyllium plantago (Pp) for the prevention of GD in obese subjects undergoing a weight-reduction diet. Patients with a body mass index (BMI = weight in Kg/square height in m) of 30 Kg/m2 or more and with normal gallbladder and biliary tree ultrasound (GBUS) were included. Weight-reduction diets were individually calculated for each patient according to their energy expenditure (EE). Patients were randomly and blindly assigned either to group I (diet + 750 mg UDA + fiber placebo) or group II (diet + 15 g Pp+ UDA placebo). An anthropometric evaluation was performed to each patient before and after the two-month treatment, as well as resting EE by indirect calorimetry, GBUS and endoscopy for the determination of cholesterol crystals in duodenal bile. Weight reduction was similar in both groups (group I = 6 +/- 2 Kg vs group II = 6 +/- 3 Kg). GD development was observed in one patient of group I (5.5%) and two patients of group II (p > 0.05). All patients with GD lost a minimum of 4 Kg during the study period. GD development did not correlate with the presence of crystals in the duodenal bile at the beginning of the study. Our results suggest a beneficial effect of a rational diet with fiber supplementation to prevent GD development in obese patients included in a weight reduction program.