The Brazilian national prospective active surveillance (AS) cohort of patients with low-risk prostate cancer in the public health system: vigiaSUS study protocol.

BACKGROUND: Prostate cancer exhibits a very diverse behaviour, with some patients dying from the disease and others never needing treatment. Active surveillance (AS) consists of periodic PSA assessment (prostate-specific antigen), DRE (digital rectal examination) and periodic prostate biopsies. According to the main guidelines, AS is the preferred strategy for low-risk patients, to avoid or delay definitive treatment. However, concerns remain regarding its applicability in certain patient subgroups, such as African American men, who were underrepresented in the main cohorts. Brazil has a very racially diverse population, with 56.1% self-reporting as brown or black. The aim of this study is to evaluate and validate the AS strategy in low-risk prostate cancer patients following an AS protocol in the Brazilian public health system. METHODS: This is a multicentre AS prospective cohort study that will include 200 patients from all regions of Brazil in the public health system. Patients with prostate adenocarcinoma and low-risk criteria, defined as clinical staging T1-T2a, Gleason score ≤ 6, and PSA < 10 ng/ml, will be enrolled. Archival prostate cancer tissue will be centrally reviewed. Patients enrolled in the study will follow the AS strategy, which involves PSA and physical examination every 6 months as well as multiparametric MRI (mpMRI) every two years and prostate biopsy at month 12 and then every two years. The primary objective is to evaluate the reclassification rate at 12 months, and secondary objectives include determining the treatment-free survival rate, metastasis-free survival, and specific and overall survival. Exploratory objectives include the evaluation of quality of life and anxiety, the impact of PTEN loss and the economic impact of AS on the Brazilian public health system. DISCUSSION: This is the first Brazilian prospective study of patients with low-risk prostate cancer under AS. To our knowledge, this is one of the largest AS study cohort with a majority of nonwhite patients. We believe that this study is an opportunity to better understand the outcomes of AS in populations underrepresented in studies. Based on these data, an AS national clinical guideline will be developed, which may have a beneficial impact on the quality of life of patients and on public health. TRIAL REGISTRATION: Clinicaltrials registration is NCT05343936.

Differential diagnosis of mesenchymal neoplasms of the digestive tract by cell block and immunohistochemistry.

OBJECTIVES: To evaluate the diagnostic yield of the cell block (CB) technique with immunohistochemistry in patients with mesenchymal neoplasms of the gastrointestinal tract collected by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). METHODS: Tissue samples from consecutive patients with subepithelial lesions collected by EUS-FNA, without analysis by on-site cytopathology, were evaluated by the same pathologist only using CBs in AAF fixative. Sections were stained with haematoxylin-eosin and underwent complementary immunohistochemical staining for SMA, CD117, DOG-1 and S100 in the presence of mesenchymal neoplasms. Specimens were defined as diagnostic when sufficient tissue was present for histopathological evaluation and immunohistochemistry analysis. If they were insufficient for complete evaluation, the specimens were considered nondiagnostic. RESULTS: Between September 2012 and December 2016, a total of 158 patients (median age: 57 years, 64.5% women) underwent EUS-FNA with an average of three needle passes for every lesion. The median lesion size was 17 mm. There were 113 mesenchymal neoplasms confirmed by immunohistochemistry (66 leiomyomas, 44 GISTs, two schwannomas, one leiomyosarcoma). The overall diagnostic yield of CBs was 84.17%. However, diagnosis was obtained in 98.5% (133/135) of the cases after exclusion of 23 cases in which EUS-FNA sampling was insufficient or without tumoural tissue. Only two mesenchymal neoplasms were not confirmed by CBs even after immunohistochemistry. CONCLUSIONS: CBs collected by EUS-FNA and analysed by immunohistochemistry showed a high diagnostic yield in patients with mesenchymal neoplasms, even without on-site cytopathology.

The effect of celecoxib on the development of diethylnitrosamine-induced liver tumors in rats.

BACKGROUND/AIMS: Hepatocellular carcinoma is one of the most commonly diagnosed malignant tumors in the world, and it typically has a poor prognosis. Extensive studies have examined the effects of non-steroidal anti-inflammatory drugs selective to COX-2 on the chemoprevention of various tumors. The objective of this study is to observe the effect of celecoxib on the development of liver tumors in rats. MATERIAL AND METHODS: Hepatocellular carcinoma was induced in a group of 75 rats with the carcinogen diethylnitrosamine. The animals were divided into 5 groups. Three groups received various doses of celecoxib, one group received indomethacin, and a control group received no non-steroidal selective anti inflammatory drugs. RESULTS: The experimental model was considered to be successful because 78% of the rats in the control group developed liver tumors. The number of neoplastic lesions was similar among the celecoxib, indomethacin and control groups, although the nodule diameter of the lesions was smaller in the celecoxib group. Better results were observed in animals that received celecoxib at doses of 6 and 9 mg/kg/ day; 4 rats in these groups did not show any neoplastic histological lesions, and a greater proportion of the nodules in the other animals in these groups were benign than in the groups that did not use celecoxib. CONCLUSIONS: These results suggest that celecoxib may play a role in modifying the natural history of hepatocellular carcinoma development.

Evaluation of the C3435T polymorphism in the MDR1 gene in patients with hepatocellular carcinoma.

INTRODUCTION: Considering the high prevalence of liver tumors and the impact on patient survival, a greater understanding of the biological behavior of those tumors if of great importance. The multidrug resistance gene (MDR1) may present as single nucleotide polymorphism (SNP) which can affect the expression and activity of P-glycoprotein (Pgp), and high expression of Pgp has been associated with a worse prognosis in affected patients. OBJECTIVE: To correlate the C3435T polymorphism in the MDR1 gene with the immunohistochemical expression of Pgp. MATERIAL AND METHODS: A total of 67 samples from patients with diagnosis of hepatocellular carcinoma (HCC), collected in the period from 2000 to 2009, were analyzed. The polymorphism in the MDR1 gene was determined by the technique of allele-specific real time PCR using TaqMan assay, and the expression of protein Pgp was evaluated by immunohistochemistry. RESULTS: Among the samples evaluated, 56 (83.6%) were from male patients and 11 (16.4%) from females. Mean age was 60.6 years (± 8.8), ranging from 37 to 85 years. The etiology of the HCC was related to hepatitis C virus infection (HCV) in 31 (46.3%) of cases, followed by hepatitis C virus infection + alcohol in 24 cases (35.8%), alcohol in 4 cases (6)%, hepatitis B virus (HBV) in 4 cases (6%) and other factors in 4 cases (6%). Liver transplantation was performed in 48 cases (71.6%) and hepatectomia in 19 cases (28.4%). The genotypes CC, CT and TT showed frequencies of 25.4%, 41.8% and 32.8%, respectively, and the allele frequencies were 46.3% for allele C and 53.7% for allele T. The expression of Pgp in over 75% of the cells was significantly more frequent in tumor tissue. On the other hand, a low expression of Pgp, in less than 25% of the cells, was significantly more frequent in non-tumor tissue. The Pgp expression in more than 50% of tumor cells of individuals with genotypes CC, CT and TT was 15.7%, 51.0% and 33.3%, respectively, and was significantly higher when in the presence of allele T (p = 0.002). CONCLUSION: The presence of the polymorphic allele T is related to increased expression of Pgp protein in patients with HCC.

Antibiotics and observation have a similar impact on asymptomatic patients with a raised PSA.

OBJECTIVES: • To compare the influence of a 4-week course of empirical antimicrobial therapy or observation on the prostate-specific antigen (PSA) levels of asymptomatic patients with a raised baseline PSA. • To identify whether a decrease in PSA can predict the risk of prostate cancer (PCa) detection on prostate biopsy. PATIENTS AND METHODS: • Patients were referred to our ambulatory centre because of a raised PSA level (>2.5 ng/mL) with a normal digital rectal examination. A 12-core prostate biopsy was indicated in these patients and they were offered antibiotic treatment with levofloxacin 500 mg daily for 30 days. • Patients who did not agree to use antibiotics but who still showed interest in participating underwent simple observation, serving as controls. • Total and free PSA levels at baseline and after 45 days were measured. Variation in PSA level was calculated. • All patients underwent a 12-core prostate biopsy 6 weeks after the initial visit. RESULTS: • In all, 245 men were enrolled, but 43 were lost due to follow-up. A total of 145 patients who used antibiotics and 57 controls were included in the analysis. • The median baseline PSA levels were 7.6 and 7.7 ng/mL in the antibiotic and control groups, respectively, with median follow-up levels of 6.8 and 7.0 ng/mL. The follow-up PSA level was significantly lower than the initial PSA level (P = 0.009). • Mean absolute and percentage variation in PSA level were similar in both groups (P = 0.828 and 0.128, respectively). • The overall PCa detection rate was 15.8%, and did not differ among the groups (P = 0.203). Regarding the percentage variation in PSA level, patients diagnosed with PCa tended to have their PSA level increased (22.4 vs -5.3%; P = 0.001). Indeed, a decrease of 20% in PSA was not predictive of a negative prostate biopsy (P = 0.41). • The area under the receiver operating characteristic curve for percentage PSA variation as a predictor of PCa was 0.660. CONCLUSIONS: • PSA levels tend to fall when repeated after 45 days, regardless of antibiotic use. • Despite being associated with the chance of PCa, no percentage PSA variation threshold value exhibits satisfactory discriminatory properties.

The role of linear endosonography for the diagnosis of acute pancreatitis when other methods failed.

BACKGROUND AND STUDY AIMS: Acute pancreatitis has no obvious cause after clinical, laboratory and radiologic investigation in 10%-30% of patients, and the diagnosis of idiopathic pancreatitis is given. This study investigated the role of linear EUS for identification of possible causes for acute pancreatitis when other investigative methods failed. PATIENTS AND METHODS: Between June 2012 and March 2017, 35 patients [25 women; mean age: 51.9 + 17.8 years] with idiopathic acute pancreatitis underwent linear EUS for investigation. All of these cases were contacted for a follow-up telephone interview to compare the EUS findings with the final diagnosis and outcome. RESULTS: Pancreaticobiliary abnormalities were identified in 19 of 35 (54.3%) patients. Ten (28.6%) patients had microlithiasis or biliary sludge. Microlithiasis and choledocholithiasis were identified in 8 (22.8%) and a single (2.8%) patient, respectively. Two patients presented gallbladder biliary sludge, one of them with microlithiasis. Chronic pancreatitis was found on EUS in 6 (17.1%) patients, and pseudotumoral masses confirmed by EUS-FNA as autoimmune pancreatitis were detected in other 3 (8.6%) cases. Linear EUS was normal in 13 (37.1%) patients, and demonstrated findings of recent acute pancreatitis but no other etiological factor in 3 (8.6%) cases. After a mean follow-up of 33.3 months, no case with a normal EUS evaluation presented a new episode of pancreatitis, 1 of 9 cases with microlithiasis presented an episode of recurrent pancreatitis due to choledocolithiasis after cholecystectomy, and 3 of 9 cases with chronic pancreatitis presented recurrent episodes, including the 2 cases of autoimmune pancreatitis. CONCLUSIONS: Linear EUS provides diagnostic information in approximately a half of patients with idiopathic acute pancreatitis. Exclusion of pancreaticobiliary abnormalities on EUS has an important prognostic value for absence of new episodes of acute pancreatitis.

EUS-FNA WITH 19 OR 22 GAUGES NEEDLES FOR GASTRIC SUBEPITHELIAL LESIONS OF THE MUSCLE LAYER.

BACKGROUND: Tissue diagnosis is required for gastric subepithelial lesions for differential diagnosis of GISTs. However, there has not been consensus about the best needle for EUS-guided sampling of these lesions. AIM: To evaluate the diagnostic yield of EUS-FNA for gastric subepithelial lesions of the proper muscle layer with large-bore 19 gauge needles. METHODS: A prospectively maintained database was retrospectively reviewed to identify consecutive patients who underwent EUS-FNA with 19 and 22 gauge needles for gastric subepithelial lesions of the fourth endosonographic layer in a tertiary care referral center. EUS-FNA was performed by the same endosonographer, using the fanning technique, without on-site cytopathologist. Specimens were analysed through cell blocks by the same pathologist. Procedure results were categorized into diagnostic, defined as enough material for histopathology and immunohistochemistry, or nondiagnostic. RESULTS: Eighty-nine patients (mean age: 59 years, 77% women) underwent 92 EUS-FNA with 19 (75) or 22 (17) gauge needles. Mean lesion size was 22.6 mm. Overall diagnostic yield was 88%. The diagnostic yield of 19 gauge was higher than that of 22 gauge needle (92%x70.6%; p=0.0410), and similar for lesions >2 cm and <2 cm (93.7%x90.7%; p=0.9563). The best performance for 19 gauge needles was obtained performing <3 needle passes. Complication rate was 2.8%. CONCLUSIONS: Diagnostic yield of EUS-FNA with 19 gauge needles is 92% for gastric subepithelial lesions of the proper muscle layer. It is safe and highly valuable for differentiation between GIST and leiomyoma, no matter the size of the lesion.

Expression of mucin-2 and correlation with PAS-alcian blue stain in Barrett's esophagus.

BACKGROUND/AIMS: Hematoxylin-eosin stain may fail to show intestinal metaplasia in Barrett's esophagus, and PAS-alcian blue may present difficulties of interpretation due to its more heterogeneous staining. We investigated whether Mucin-2 is a good substitute for PAS-alcian blue in the detection of goblet cells. METHODOLOGY: Biopsy specimens from 47 Barrett's esophagus patients were stained with hematoxylineosin and PAS-alcian blue. Mucin-2 expression was evaluated with monoclonal antibody. The intra- and interobserver agreements about the expression of Mucin-2 and PAS-alcian blue stain were determined by kappa statistics. RESULTS: PAS-alcian blue and Mucin-2 were positive in all cases. Mucin expression was positive in goblet cells and few columnar cells. PAS-alcian blue showed heterogeneous staining. The columnar epithelium and the submucosal glands were also stained. Intra- and interobserver agreement in the identification of intestinal metaplasia was 100%. CONCLUSIONS: Mucin-2 agreed fully with PAS-alcian blue. The intra- and interobserver agreement was perfect, justifying its use in the diagnosis of Barrett's esophagus.

[Potentially pre-neoplasics areas in rat's liver associated to chronic use of phenobarbital]. / A relação do uso crônico de fenobarbital com áreas potencialmente pré-neoplásicas em fígado de ratos.

BACKGROUND: Phenobarbital has been used in experimental models because it is an important agent of carcinogenesis promotion in the liver of rats, and it is also non-genotoxic, organ-specific and dose-dependent. AIM: To evaluate the effects of the daily administration of phenobarbital in old rats treated with phenobarbital since their birth up to 24 months of age, in the absence of concomitant administration of chemical agents, which initiate carcinogenesis. PATIENTS AND METHODS: A control group of male Wistar rats was fed with a basic diet and a second group was fed with the same basic diet added of 0.05% of phenobarbital, for a period of 24 months. Medium and right liver fragments were submitted to the histological processing and they were stained by hematoxiciline and eosin and were immunohystochemically colored to glutathione S-transferase placentary form. RESULTS: Glutathione S-transferase placentary positive zones were detected in both groups and the images were analyzed concerning their number and surface extension through the technique of histometry analyses. CONCLUSION: Chronic use of phenobarbital did not modify the number of glutathione S-transferase placentary form positive areas. Although, data indicates that glutathione S-transferase placentary form positive areas media size are increased, probably because there are an increase in their evolution capacity and irreversibility.

Use of the gamma probe in sentinel lymph node biopsy in patients with prostate cancer.

OBJECTIVE: To describe the reproducibility of the sentinel lymph node technique in patients with prostate cancer and verify if there is improved accuracy over modified lymphadenectomy. MATERIAL AND METHODS: Twenty-three patients with biopsy proven prostate cancer were enrolled in this study. Lymphoscintigraphy was performed after the transrectal administration of Tc sulfur colloid guided by ultrasound, with one injection in each prostate lobe. Images were obtained 15 and 180 min after injection. Sentinel lymph node was harvested during surgery using a gamma probe, followed by extended lymphadenectomy. RESULTS: The mean age of the patients in this study was 66 years. An average of 3.36 sentinel lymph nodes was found for each patient. Radioactive lymph nodes were identified by the gamma probe in 21 out of 23 patients. In one of the patients there was no radiopharmaceutical migration from the injection site and in another the sentinel lymph node was visualized by lymphoscintigraphy but was not found during surgery. Three patients had lymph node metastasis; in one of these patients the sentinel lymph node was the only positive node and was found outside the modified lymphadenectomy region (obturator fossa and the external iliac). CONCLUSION: Sentinel lymph node biopsy in prostate cancer adds important information to the staging of patients, not always attained through the lymphadenectomy restricted to the obturator fossa and external iliac. Such information is essential for the choice of the best treatment to be applied.

[Does the criterium of positivity for the immunohistochemical analysis of p53 in the confirmation of Barrett's dysplasia make any difference?]. / O critério de positividade para a análise imunoistoquímica da p53 na confirmação da displasia do esôfago de Barrett faz diferença?

BACKGROUND: Barrett's esophagus is the most serious complication of the gastroesophageal reflux disease and presents a malignant potential. The expression of the tumoral marker p53 increases with the dysplasia-adenocarcinoma sequence. AIMS: To evaluate the p53 expression in Barrett's esophagus with or without dysplasia according to the two positive immunostaining criteria. MATERIALS AND METHODS: The material was constituted by endoscopic biopsy specimens from 42 patients with Barrett's esophagus. Section of formalin-fixed and paraffin-embedded biopsies were stained with hematoxylin-eosin, PAS-alcian blue and evaluated the p53 immunohistochemical expression. Two p53 immunostaining criteria were utilized: 1. The staining of, at least, half of the nuclei, and 2. The staining of any nucleus. The diagnosis of dysplasia was confirmed by the agreement between three pathologists. RESULTS: The total number of tissue specimens was 229, with an average of 5.4 specimens per patient. Dysplasia, with agreement for all pathologists examining the same set of slides, was detected in six (14.3%) cases. According to the two different p53 immunostaining criteria, the protein was detected in non-dysplastic Barrett's metaplasia, respectively, in 5 (13.9%) and 14 (38.9%) patients. Specifically in the six dysplastic cases, p53 was detected, according to the immunostaining criteria, in one (16.7%) and four (66.7%) cases, respectively. CONCLUSIONS: In this group, p53 immunohistochemical expression, regardless of positive criteria take into account, was not useful for detecting dysplasia in Barrett's esophagus.

Metastatic lymph node ratio, 6th or 7th AJCC edition: witch is the best lymph node classification for esophageal cancer? Prognosis factor analysis in 487 patients.

BACKGROUND: The esophageal cancer is one of the most common and aggressive worldwide. Recently, the AJCC changed the staging system, considering, among others, the important role of the lymph node metastasis on the prognosis. AIM: To discuss the applicability of different forms of lymph node staging in a western surgical center. METHODS: Four hundred eighty seven patients with esophageal cancer were enrolled. Three staging systems were evaluated, the 6th and the 7th AJCC editions and the Lymph Node Metastatic Ratio. RESULTS: The majority of the cases were squamous cell carcinoma. The mean lymph node sample was eight. Considering the survival, there was no significant difference between the patients when they were classified by the 7th AJCC edition. Analysis of the Lymph Node Metastatic Ratio, just on the group of patients with 0 to 25%, has shown significant difference (p=0,01). The 6th AJCC edition shows the major significant difference between among the classifications evaluated. CONCLUSION: In this specific population, the 7th AJCC edition for esophageal cancer was not able to find differences in survival when just the lymph node analysis was considered.

Evaluation of HER2 Protein Expression Using 2 New Monoclonal Antibodies.

This study describes the performance of 2 new mouse anti-HER2 monoclonal antibodies (Abs), clones 33F and 410G, in evaluating HER2 overexpression in a series of 123 invasive breast carcinoma cases. In-house immunohistochemistry (IHC) was performed and the results were compared with those for the SP3 and A0485 anti-HER2 Abs. Chromogenic in situ hybridization was used to detect ERBB2 amplification and its concordance with IHC was analyzed. Comparison of IHC results for 33F with SP3 and A0485 yielded concordance rates (K) of 0.81 and 0.75, respectively; the same concordance rates were found when comparing results for 410G with SP3 and A0485. Compared with SP3 and A0485, 33F and 410G specificities were 98.6% and 98.6%, and 100% and 100%, respectively, whereas the sensitivities were 80% and 74.1%, and 78% and 72.2%, respectively. The K values between 33F and 410G HER2+ expression and chromogenic in situ hybridization-positive amplification were 1 and 0.96, respectively. These concordance rates were reproduced in another production batch (K=0.96 and K=0.96). Together, these results show that the tested monoclonal Abs would be well suited for detecting HER2 protein overexpression by IHC.

[Dysplasia in Barrett's esophagus--intra- and interobserver variability in histopathological diagnosis]. / Displasia no esôfago de Barrett--concordância intra e interobservador no diagnóstico histopatológico.

BACKGROUND: Barrett's esophagus is a well-known pre-malignant condition. Pathologic interpretation of biopsy specimens guides endoscopic surveillance as well as the therapeutic approach that will be carried out. However, the predictive value of histopathologic diagnosis can be questioned due to its poor intra- and interobserver reproducibility. AIMS: To assess intra- and interobserver variability in the diagnosis of Barrett's dysplasia. MATERIAL AND METHODS: Three-micrometer thick sections from biopsy specimens from 42 patients with Barrett's esophagus were stained with hematoxylin-eosin and PAS-alcian blue. The reading of the slides was carried out blindly in a light microscope. Intra and interobserver variability in the interpretation of the slides was determined by kappa statistics. RESULTS: The number of tissue specimens was 229, with average of 5.45 (1 to 18) fragments for patient. Low grade dysplasia was diagnosed by pathologists in 21.4% to 52.4% of the cases. The intra-observer agreement for the diagnosis of low grade dysplasia was slight (kappa = 0.30). The interobserver agreement for the diagnosis of low grade dysplasia was poor, with kappa scores between 0.05 and 0.16. The diagnosis of dysplasia, with agreement for all pathologists examining the same set of slides, was 14.3%. CONCLUSIONS: Pathologic interpretation of Barrett's dysplasia may be subject to marked intra- and interobserver variabiliaty. Interpretation of low grade dysplasia, as high grade dysplasia, should also be considered for review by two or more pathologists.