Performance of Immunohistochemical and Molecular Methods in Detecting Microsatellite Instability in Gastric Cancer: A Multicenter Study.

INTRODUCTION: Microsatellite instability (MSI) is an important prognostic molecular biomarker for gastric cancer (GC). MSI status may be detected by immunohistochemistry (IHC) for mismatch repair (MMR) proteins and polymerase chain reaction (PCR). Idylla™ MSI assay has not been validated for GC but may prove to be a valid alternative. METHODS: In a series of 140 GC cases, MSI status was evaluated by IHC for MLH1, PMS2, MSH2, and MSH6; gold-standard pentaplex PCR panel (PPP) (BAT-25, BAT-26, NR-21, NR-24, and NR-27); and Idylla. Statistical analysis was performed using SPSS 27.0. RESULTS: PPP identified 102 microsatellite stable (MSS) cases and 38 MSI-high cases. Only 3 cases showed discordant results. Compared with PPP, the sensitivity was 100% for IHC and 94.7% for Idylla. Specificity was 99% for IHC and 100% for Idylla. MLH1 IHC alone showed sensitivity and specificity of 97.4% and 98.0%, respectively. IHC identified three indeterminate cases; all were MSS according to PPP and Idylla. CONCLUSION: IHC for MMR proteins represents an optimal screening tool for MSI status in GC. If resources are limited, isolated MLH1 evaluation may constitute a valuable option for preliminary screening. Idylla may help detect rare MSS cases with MMR-loss and define MSI status in indeterminate cases.

Impact of Gradual Adoption of EVAR in Elective Repair of Abdominal Aortic Aneurysm: A Retrospective Cohort Study from 2009 to 2015.

INTRODUCTION: The recommendations about the preferred type of elective repair of abdominal aortic aneurysm (AAA) still divides guidelines committees, even nowadays. The aim is to assess outcomes after AAA repair focusing on differences between endovascular aneurysm repair (EVAR) and open surgical repair (OSR). METHODS: The observational retrospective cohort study of consecutive patients submitted to elective AAA repair at a tertiary center, 2009-2015. Exclusion criteria were as follows: nonelective cases or complex aortic aneurysms. Primary outcomes were postoperative complications, length of hospital stay, survival, freedom from aortic-related mortality, and vascular reintervention. Time trends were assessed along the period under analysis. RESULTS: From a total of 211 included patients, those submitted to EVAR were older (74 ± 7 vs. 67 ± 9 years; P < 0.001), presented a higher prevalence of hypertension (83.5% vs. 68.5%, P = 0.004), obesity (28.7% vs. 14.3%, P = 0.029), previous cardiac revascularization (30.5% vs. 14.7%, P = 0.005), heart failure (17.2% vs. 5.2%, P = 0.013), and chronic obstructive pulmonary disease (32.8% vs. 13.3%, P = 0.002). Patients were followed during a median of 49 months. EVAR resulted in a significantly shorter length of hospital stay (median 4 and interquartile range 3 vs. 8 (9); P < 0.001), lower 30-day complications (10.6% vs. 22.8%, P = 0.017), lower aortic-related mortality, and similar reintervention after adjustment with a propensity score. Along the time under analysis, EVAR became the predominate type of repair (P = 0.024), the proportion of complications decreased (P = 0.014), and the 30-day mortality (P = 0.035). CONCLUSIONS: Although EVAR was offered to patients with more comorbidities, better and durable outcomes were achieved after EVAR, favoring its adoption for elective AAA repair.

Lithium chloride stimulates bone formation in extraction socket repair in rats.

PURPOSE: Previous evidence shows that lithium chloride (LiCl), a suppressor of glycogen synthase kinase-3ß (GSK-3ß), may enhance bone formation in several medical and dental conditions. Thus, the purpose of the current study was to assess the effects of LiCl on extraction socket repair in rats. METHODS: Thirty rats were randomly assigned into a control group (administration of water; n = 15) or a LiCl group (administration of 150 mg/kg of LiCl; n = 15). LiCl and water were given every other day, starting at 7 days before the extraction of upper first molars until the end of each experiment period. Histological sections from five rats per group were obtained at 10, 20, and 30 days post-extractions. Histometrical analysis of newly formed bone (NB) and the levels of tartrate-resistant acid phosphatase (TRAP)-stained cells were evaluated at 10, 20, and 30 days post-extractions. Immunohistochemical staining for receptor activator of nuclear factor kappa-Β ligand (RANKL), osteoprotegerin (OPG), bone sialoprotein (BSP), osteocalcin (OCN), and osteopontin (OPN) was assessed at 10 days post-extractions. RESULTS: The LiCl group had a greater proportion of NB than the control group at 20 days (P < 0.05). At 30 days, the rate of TRAP-stained cells was lower in the LiCl group than in the control group (P < 0.05). At 10 days, the LiCl group presented stronger staining for OPG, BSP, OPN, and OCN, when compared to the control group (P < 0.05). CONCLUSION: Systemic LiCl enhanced extraction socket repair, stimulated an overall increase in bone formation markers, and restricted the levels of TRAP in rats.

EBV and MSI Status in Gastric Cancer: Does It Matter?

We investigated the impactof microsatellite instability (MSI) and Epstein-Barr virus (EBV) status in gastric cancer (GC), regarding response to perioperative chemotherapy (POPChT), overall survival (OS), and progression-free survival (PFS). We included 137 cases of operated GC, 51 of which were submitted to POPChT. MSI status was determined by multiplex PCR and EBV status by EBV-encoded RNA in situ hybridization. Thirty-seven (27%) cases presented as MSI-high, and seven (5.1%) were EBV+. Concerning tumor regression after POPChT, no differences were observed between the molecular subtypes, but females were more likely to respond (p = 0.062). No significant differences were found in OS or PFS between different subtypes. In multivariate analysis, age (HR 1.02, IC 95% 1.002-1.056, p = 0.033) and positive lymph nodes (HR 1.82, IC 95% 1.034-3.211, p = 0.038) were the only prognostic factors for OS. However, females with MSI-high tumors treated with POPChT demonstrated a significantly increased OS compared to females with MSS tumors (p = 0.031). In conclusion, we found a high proportion of MSI-high cases. MSI and EBV status did not influence OS or PFS either in patients submitted to POPChT or surgery alone. However, superior survival of females with MSI-high tumors suggests that sex disparities and molecular classification may influence treatment options in GC.

A eficacia das cefalosporinas de primeira e segunda geraçao na antibioticoprofilaxia do transplante renal / Efficacy of first and second generation cephalosporins in antibiotic prophylaxis in renal transplantation

As infecçoes do trato urinario sao as infecçoes mais comuns apos o transplante renal e podem acarretar complicaçoes graves, incluindo a perda do orgao transplantado e a septicemia. A antibioticoprofilaxia tem se mostrado eficaz na reduçao da incidencia dessas infecçoes. Foi realizado um estudo prospectivo e randomizado utilizando 22 pacientes submetidos a transplante renal, os quais foram divididos em dois grupos com 11 pacientes cada. O grupo A recebeu antibioticoprofilaxia com cefazolina, uma cefalosporina de primeira geraçao, e o grupo B recebeu antibioticoprofilaxia com cefoxitina, uma cefalosporina de segunda geraçao. A profilaxia iniciou-se no pre-operatorio imediato e estendeu-se ate o decimo dia apos a cirurgia. Durante esse periodo, os pacientes foram submetidos a monitorizaçao clinica (curva termica) e laboratorial (analise do sedimento urinario, urocultura e homocultura). Apenas dois pacientes (9 por cento) apresentaram infecçao do trato urinario na vigencia da antibioticoprofilaxia, sendo uma em cada grupo. Nao foram observados efeitos colaterais ou alteraçao da funçao renal durante o periodo do estudo. As cefalosporinas de primeira e segunda geraçao mostraram-se igualmente eficazes na prevençao de infecçoes apos o transplante