Antonieta Solar

Gastric Cancer after Roux-en-Y Gastric Bypass

Roux-en-Y gastric bypass (RYGBP) is one of the most commonly performed surgical procedures for morbid obesity. Several complications that may develop in the short- and long-term have been reported. We present a patient who presented with cancer in the bypassed stomach 8 years after RYGBP. Although the development of this lesion is rare and only a few cases have been reported, there are aspects worthy of discussion. Several monitoring, diagnostic and therapeutic alternatives are analyzed.

Comparative analysis of loss of heterozygosity and microsatellite instability in adult and pediatric melanoma

Although 0.3% of melanomas occur in children, the incidence has risen in past decades. In adult melanoma, some chromosomal regions in 1p, 6q, 9p, 10q, and 11q are frequently deleted. Microsatellite instability (MSI), which reflects impaired DNA repair, has been found at low levels in adult melanoma and melanocytic nevi. To investigate the molecular changes in pediatric melanoma, a screening for loss of heterozygosity and microsatellite instability was performed and compared with changes found in adult melanoma. Formalin-fixed, paraffin-embedded tissues from 10 adult melanomas, 9 melanocytic nevi, and 8 pediatric melanomas were microdissected and the DNA was extracted. Loss of heterozygosity and microsatellite instability were evaluated using 13 microsatellite repeat polymorphisms located in 1p36, 1q32, 2p12, 2p22-25, 2q33-37, 9p21, 10q23.3, 11q23, 13q14, 17p13, and 17q21. The overall frequency of loss of heterozygosity was 0.09 for nevi, 0.30 for adult melanoma, and 0.43 for pediatric melanoma (nevi vs. adult melanoma, P = 0.0082; nevi vs. pediatric melanoma, P = 0.0092). Pediatric melanoma has more loss of heterozygosity (44%) in 11q23 than adult melanoma (7%, P = 0.046). The microsatellite instability overall frequency was greater in pediatric melanoma (0.24) than nevi (0.05, P = 0.0031) and adult melanoma (0.09, P = 0.0195). Our findings suggest that pediatric melanoma has a different abnormal pattern than adult melanoma. Pediatric melanoma has more microsatellite instability than adult melanoma. 11q23 could contain genes related to the early age onset of melanoma. The high frequency of microsatellite instability is coincidental with the finding of higher levels of microsatellite instability in pediatric brain tumors and could play a role in the pathogenesis of pediatric melanoma.

Arteriovenous malformation of the pancreas: report of a case.

Arteriovenous malformation (AVM) of the pancreas (AVMP) is uncommon and generally asymptomatic; therefore, few cases have so far been reported. The symptoms of AVMP include gastrointestinal bleeding, pain, and portal hypertension. Definitive diagnosis is confirmed by angiographic study, and surgery is the only effective treatment. We report a case of AVMP confirmed by computed tomography, magnetic resonance imaging, and angiographic study of the abdomen, in a patient who presented to us with epigastric pain. He underwent a pancreaticoduodenectomy, following which his symptoms resolved.

An ultrasound model to discriminate the risk of thyroid carcinoma.

RATIONALE AND OBJECTIVES Thyroid nodules are common on ultrasonographic examination and are mostly benign. Ultrasound characteristics may help discriminate thyroid carcinoma (TC) from benign nodules. The aims of this study were to identify ultrasonographic characteristics associated with TC and to validate a previously proposed model based on the presence of three ultrasonographic characteristics. MATERIALS AND METHODS From a protocolized prospective registry of 1108 fine needle aspiration biopsies performed during a 16-month period at an ambulatory center, the ultrasonographic characteristics of TC and non-TC biopsies were compared. Adjusted odds ratios (ORs) and likelihood ratios for TC were estimated for eight combinations of three previously identified characteristics (microcalcifications, hypoechogenicity, and irregular borders). RESULTS Microcalcifications (OR, 6.6; 95% confidence interval [CI], 4.4-9.9), hypoechogenicity (OR, 4.7; 95% CI, 2.8-8.0), and irregular borders (OR, 4.3; 95% CI, 2.8-6.5) were independently associated with TC. When added to a logistic regression model, the three ultrasonographic characteristics remained statistically significant. In the absence of these three features, the likelihood ratio for TC was 0.1 (95% CI, 0.0-0.2), while in their simultaneous presence, the likelihood ratio was 11 (95% CI, 6.6-19.0). CONCLUSIONS The absence or simultaneous presence of three simple ultrasonographic characteristics generates a large change of pretest probability of TC and could avoid unnecessary fine needle aspiration biopsy.

Cervical metastases of glucagonoma in a patient with multiple endocrine neoplasia type 1: Report of a case

Multiple endocrine neoplasia type 1 (MEN 1) is a syndrome characterized by tumors of the parathyroid glands, pancreatic islet cells, duodenum, and pituitary gland. We report a case of cervical metastases of glucagonoma with MEN 1. The patient was a 34-year-old woman admitted to our hospital with epigastric pain. Her medical history included two resections of prolactinoma and two upper GI hemorrhages secondary to duodenal ulcers. Computed tomography (CT) showed two hypervascular lesions in the tail of the pancreas and cervical ultrasound showed multiple hypoechogenic ovoid images in the neck. A cervical CT scan confirmed two 15-mm lymph nodes in the left cervical region and 111In-DOTATOC imaging showed focal abnormal somatostatin expression in the pancreatic tail and the cervical nodes. The patient had asymptomatic hypoglycemic episodes, with blood sugar levels as low as 30 mg/dl, which raised our suspicion of MEN 1 associated with pancreatic insulinoma. Thus, we performed a distal pancreatectomy with bilateral cervical dissection and parathyroid gland resection. Histopathological examination revealed 12 pancreatic tumors as well as metastases in four cervical lymph nodes. The resected parathyroid glands had normal structure, suggesting parathyroid hyperplasia. A follow-up CT scan, 18 months after surgery, showed new tumors in the head of the pancreas and in the duodenal wall. A pancreatoduodenectomy was performed and histopathological examination revealed nine nonfunctioning endocrine tumors in the pancreas, one tumor in the duodenal wall, and metastases in two peripancreatic lymph nodes. The patient recovered well and remains asymptomatic.

Diseño de una escala ecográfica predictora de malignidad en nódulos tiroideos: Comunicación preliminar

One hundred twenty two biopsies of atotal of 1,498 were conclusive for PTC. Univariate analysis showed associations with PTC for thepresence of micro-calcifications (Odds ratio (OR) 49.2: 95% confidence intervals (CI) 18.7-140.9),solid predominance (OR 25.1; 95% CI 6-220), hypoechogenicity (OR 23.5, 95% CI 6.5-122.6),irregular borders (OR 17, 95% CI 7.2-42.9), lymph node involvement (OR 12.3, 95% CI 2.7-112),central vascularization (OR 12.2, 95% CI 4.8-33.3), local invasion and hyperechogenicity (OR 0.2;CI 95% CI 0.03-0.6). Multivariate analysis disclosed microcalcifications (OR 28.1; CI 95% 8.9-89),hypoechogenicity (OR 9.4; 95% CI 1.5-59.5) and irregular borders (OR 4.7; CI 95% 1.5-15) as thevariables independently associated with the presence of PTC. The prevalence of PTC in the presenceof the three variables was 97.6% (Likelihood ratio (LR) 45) and 5.4% in their absence (LR 0.06).

Carcinoma familiar del tiroides no medular (CFTNM): características de presentación en 17 casos

Retrospective analysis of medical records of patients with thyroid carcinoma. An index case wasdefined as a subject with the diagnosis of differentiated thyroid carcinoma with one or morefirst degree relatives with the same type of cancer. Seventeen such patients were identified andwere compared with 352 subjects with PTC.

New splicing mutation of MEN1 gene affecting the translocation of menin to the nucleous

Multiple endocrine neoplasia type 1 (MEN1) is a syndrome inherited in an autosomal dominant trait caused by the inactivation of the tumor suppressor gene MEN1. Objective: To communicate a family with a new heterozygous germ line mutation in the intronic region of MEN1 gene and to study its influence in the menin expression. Patients and Methods: We studied 5 members of a family with symptomatic hyperparathyroidism (HPT). One of them had also a neuroendocrine pancreatic tumor, and 2 had non-functional multinodular cortical adrenal hyperplasia compatible with the diagnosis of MEN1. After the mutation was identified, HSP92II restriction enzyme was used to determine both zygosity and segregation of the mutation. RT-PCR from leukocyte’s isolated mRNA and western blot from pancreatic tumor tissue were performed. In vitro studies were done in Chinese hamster ovary (CHO) cells transfected with reporter minigenes carrying the coding regions spanning exon (EX)-intron 9 and EX10 with the mutant and the wild type sequences. Results: We identified a heterozygous G-to-T substitution in the intron-EX junction (IVS9-1 G>T) of MEN1 gene in the index case and the family members. The mRNA from patient’s leukocytes was larger (934 bp) in comparison to the normal transcript (717 bp). Immunoblot analysis demonstrated that wild type (67 kDa) and two additional mutant proteins (~55 and ~90 kDa) were expressed in the pancreatic tissue. The in vitro study showed a 45% nuclear localization of the mutated menin signal and a 95% in the wild type protein. Conclusions: We identified a new intronic heterozygous germ line mutation (IVS9-1G>T) of MEN1 gene in a family affected by MEN1 syndrome. This mutation alters the splice acceptor site of intron 9 that promotes an incorrect splicing, generating aberrant proteins without the nuclear localization signals necessary for the normal menin translocation to the nucleus.

Differential expression profile of CXCR3 splicing variants is associated with thyroid neoplasia. Potential role in papillary thyroid carcinoma oncogenesis

Papillary thyroid cancer (PTC) is the most prevalent endocrine neoplasia. The increased incidence of PTC in patients with thyroiditis and the frequent immune infiltrate found in PTC suggest that inflammation might be a risk factor for PTC development. The CXCR3-ligand system is involved in thyroid inflammation and CXCR3 has been found upregulated in many tumors, suggesting its pro-tumorigenic role under the inflammatory microenvironment. CXCR3 ligands (CXCL4, CXCL9, CXCL10 and CXCL11) trigger antagonistic responses partly due to the presence of two splice variants, CXCR3A and CXCR3B. Whereas CXCR3A promotes cell proliferation, CXCR3B induces apoptosis. However, the relation between CXCR3 variant expression with chronic inflammation and PTC development remains unknown. Here, we characterized the expression pattern of CXCR3 variants and their ligands in benign tumors and PTC. We found that CXCR3A and CXCL10 mRNA levels were increased in non-metastatic PTC when compared to non-neoplastic tissue. This increment was also observed in a PTC epithelial cell line (TPC-1). Although elevated protein levels of both isoforms were detected in benign and malignant tumors, the CXCR3A expression remained greater than CXCR3B and promoted proliferation in Nthy-ori-3-1 cells. In non-metastatic PTC, inflammation was conditioning for the CXCR3 ligands increased availability. Consistently, CXCL10 was strongly induced by interferon gamma in normal and tumor thyrocytes. Our results suggest that persistent inflammation upregulates CXCL10 expression favoring tumor development via enhanced CXCR3A-CXCL10 signaling. These findings may help to further understand the contribution of inflammation as a risk factor in PTC development and set the basis for potential therapeutic studies.

Effect of propionibacterium acnes (PA) injection on intervertebral disc degeneration in a rat model: does it mimic modic changes?

INTRODUCTION Multiple reports of bacterial isolates in human disc tissue have suggested a role of low-grade infection on intervertebral disc degeneration and modic changes (MC) generation. Animal models have been extensively used to study IDD; however, until recently, no consideration had been given to eventual infectious processes. To reproduce the phenomena by inoculating an infecting agent would support the infectious hypothesis. Therefore, we studied the effect of Propionibacterium acnes (PA) inoculation on rat-tails and determined whether it would produce MCs on the adjacent endplates. HYPOTHESIS Disc infection with PA would accelerate IDD compared with the standard model and would also lead to MCs on the adjacent endplates. METHODS Twelve Sprague-Dawley rats were randomized to receive a needle puncture in a caudal tail disc with either saline (control) or an inoculum of 5×107 CFU of strain 1a PA. Twelve weeks later, the rats were euthanized and the tails were analyzed. The main assessment criteria were obtained from the post-mortem MRI: T2 values of punctured discs and adjacent endplates, as well as disc volumes. A histological grading score for IDD was also used, measuring the morphology and cellularity of the nucleus and annulus, as well as endplate disruption. RESULTS The median T2 value and disc volume were smaller in PA-punctured discs [T2 value: 30ms (23-44) vs. 61ms (38-132), respectively, P=0.01; 0.01mm3 (0.01-0.05) vs. 0.5mm3 (0.01-5.35), respectively; P=0.049]. There was no change in the adjacent endplates. There was no significant difference in histological grading between the test and control [13 (10-14) vs. 10.5 (6-13); P=0.05]. DISCUSSION Inoculation of caudal discs with PA generated increased degeneration; however, no MCs were observed on the adjacent endplates. A better understanding of low-grade disc infections is still needed. LEVEL OF EVIDENCE V (animal study).