Patricia Pontes

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 Idy...

Evaluation of mismatch repair (MMR) protein and microsatellite instability (MSI) status plays a pivotal role in the management of gastric cancer (GC) patients. In this study, we aimed to evaluate the accuracy of gastric endoscopic biopsies (EBs) in predicting MMR/MSI status and to uncover histopathologic features associated with MSI. A multicentric series of 140 GCs was collected retrospectively, in which EB and matched surgical specimens (SSs) were available. Laurén and WHO classifications were applied and detailed morphologic characterization was performed. EB/SS were analyzed by immunohistochemistry (IHC) for MMR status and by multiplex polymerase chain reaction (mPCR) for MSI status. IHC allowed accurate evaluation of MMR status in EB (sensitivity: 97.3%; specificity: 98.0%) and high concordance rates between EB and SS (Cohen κ=94.5%). By contrast, mPCR (Idylla MSI Test) showed lower sensitivity in evaluating MSI status (91.3% vs. 97.3%), while maintaining maximal specificity (1...

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 incr...

Microsatellite instability (MSI) is a molecular phenotype due to a deficient DNA mismatch repair (dMMR). In colorectal cancer (CRC), dMMR/MSI is associated with several clinical and histopathological features, influences prognosis, and is a predictive factor of response to therapy. In daily practice, dMMR/MSI profiles are identified by immunohistochemistry and/or multiplex PCR. The Thomsen–Friedenreich (TF) antigen was previously found to be a potential single marker to identify MSI-high gastric cancers. Therefore, in this study, we aimed to disclose a possible association between TF expression and MSI status in CRC. Furthermore, we evaluated the relationship between TF expression and other clinicopathological features, including patient survival. We evaluated the expression of the TF antigen in a cohort of 25 MSI-high and 71 microsatellite stable (MSS) CRCs. No association was observed between the expression of the TF antigen and MSI-high status in CRC. The survival analysis reveal...

Background Anal squamous cell cancer is an HPV associated disease, highly prevalent in HIV-infected men who have sex with men (MSM). We evaluate the prevalence of HPV infection in an HIV-positive MSM population attending our hospital. Cytological results are correlated with an HR-HPV genotype. Methods From February 2013 to July 2014, 95 anal Thin Prep cytologies and 17 histological specimens were evaluated in 89 HIV-infected MSM. HPV detection (cobas® HPV Test) was done in 78 patients. Patients with a positive cytological result were biopsied according to the recommendations of the European Society for Medical Oncology Clinical Practical Guidelines. The STATVIEW statistical computer program was used. Results The mean age was 37 years. Cytological results: 40% - NILM, 17.9% - ASCUS, 24.2% - LSIL, 4.2% - HSIL and 1.1% - AGC. The overall prevalence of HR-HPV was of 80.8%. In 76.9% of the cases, infection occurred with multiple HR-HPV genotypes. The "other" HR-HPV pattern was the most prevalent HR-HPV genotype. Considering age, HPV-16 prevalence was 50.0% and 28.6% in patients under and over 30 years, respectively. A histological specimen was obtained from 17 patients and 82.4% of them had AIN. Conclusion 1 - HIV-infected MSM is a highly HR-HPV genotype infected population; 2 - The multiple infection pattern was the most prevalent; 3 - "Other", an HPV subtype was the most prevalent pattern; 4 - The prevalence of HPV infection and multiplicity of infection was directly related to the severity of the cytological abnormalities and age; 5 - HPV-16 prevalence was more prevalent in patients under 30 years.

The contribution of human papillomavirus (HPV) types to the carcinogenesis of cervical cancer has been established for a long time. However, the role of phylogenetically related and rare variants remains uncertain, as well as the influence of concurrent multiple HPV genotypes infection. We aimed at studying the prevalence of several HPV genotypes infecting women with single versus concurrent multiple HPV genotypes infection with a HSIL diagnosis in a cervical cytology. We conducted a cross-sectional study using Thin-Prep(®) liquid-based cervical cytology specimens with the diagnosis of high-grade squamous intraepithelial lesion (HSIL), in which HPV genotype was sequentially tested. Genotypes were determined with a PapilloCheck(®) system, a DNA-Chip for the type-specific identification of 18 high-risk and six low-risk types of HPV. Of the total study population, 176 cases had a diagnosis of HSIL and positive HPV genotyping result, being HPV16 the most prevalent genotype (48.86%; 95%CI: 41.58-56.19) followed by HPV31 (14.20%; 95%CI: 9.75-20.18). Concurrent multiple HPV genotypes were detected in 36.93% (95%CI: 30.15-44.27) of the patients. The prevalence of the 10 most common HPV genotypes detected varied significantly according to the presence of single vs. concurrent multiple HPV genotypes (P = 0.022). Moreover, women with concurrent multiple HPV genotypes were on average 3.53 (95%CI: 0.43-6.64) years younger than women with single genotype infection. Our results suggest that women with multiple genotype HPV infection differ in terms of age and distribution of the most prevalent HPV genotypes. Additionally, we provide further evidence of the predominance of HPV16 in HSIL lesions of the uterine cervix.

Among bio-banking initiatives, tumour banking plays a pivotal role in biomedical research. The general aim of a Tumour Bank is to acquire neoplastic and control non-neoplastic samples, in standardized conditions for research (basic, clinical or translational). A Tumour Bank is a ...