Application of One-Step Nucleic Acid Amplification (OSNA) in different cancer entities and usefulness in prostate cancer: a systematic review.

BACKGROUND: Lymph node (LN) status is a key prognostic factor in the decision-making process of different cancer entities, including prostate cancer (PCa). Sectioning and haematoxylin and eosin (H&E) staining technique remain the gold standard for the evaluation of LN metastases despite some limitations, especially low sensitivity in detecting an accurate tumour burden within the LN, as well as a subjective and time-consuming result. One-step nucleic acid amplification (OSNA) quantifies mRNA copies of cytokeratin 19 (CK19) in a fast, objective, automated, and reproducible way, raising a general interest to explore its utility for lymphatic metastasis identification in different malignancies. METHODS: To present the latest evidence related to the detection of LN metastases in several tumours by using OSNA compared with the conventional H&E method, a systematic review of articles published since March 2021 was conducted using PubMed, Cochrane Library, and Web of Science databases. References from primary papers and review articles were checked to obtain further potential studies. Our procedure for evaluating records identified during the literature search followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses criteria. With the aim to design and justify future clinical routine use of OSNA in PCa, novel PCa evidence has been included in this review for the first time. RESULTS: Twenty five studies were included. LN from six different groups of tumours: breast, gastrointestinal, gynecological, lung, head and neck and prostate cancers has been assessed. OSNA was compared with post-operative formalin-fixed paraffin-embedded tissue sections with H&E staining as the reference standard. Contingency tables were created, and concordance rate, sensitivity, specificity and predictive values were reported. Seventeen studies analysed the discordant cases using different techniques. CONCLUSION: OSNA method has a high diagnostic accuracy for the detection of LN metastases in several CK19 expressing tumours. Available evidence might encourage future investigations about its usage in PCa patients to improve LN staging and prognosis.

Is Tumor Budding a New Predictor for Early Cystectomy in pT1 High-Grade Bladder Cancer?

Background & Objectives: We aimed to evaluate the risk of progression in high-grade T1 (HGT1) tumors using tumor budding (TB) and other standard clinical and histological features. TB is defined as an isolated cancer cell or a cluster composed of fewer than 5 cells scattered in the stroma and is usually used as a strong predictor of lymph node metastasis in T1 colorectal cancer. METHODS: This is an observational longitudinal cohort study involving 168 consecutive patients with HGT1 between 2013 and 2016. Cox regression was performed to analyze the relationship between the clinical and histological features and progression. All slides were blindly assessed by 2 genitourinary pathologists. Budding was determined to be positive when the number of buds was equal to or greater than 6. RESULTS: The median age was 75 years; 152 (90.5%) patients were men, and 49 (29.2%) were positive for TB. At a median follow-up time of 35 months, 33 patients (19.6%) showed progression. Progression was observed in 32.7% of the patients positive for TB and in only 14.3% of those who were negative (p = 0.006). TB was significantly associated with the endoscopic tumor pattern (TP) (papillary/solid) and lymphovascular invasion (LVI). Univariate analysis showed that TB, carcinoma in situ (CIS), TP, LVI, sub-staging, and BCG induction predict progression. The multivariate analysis showed that TB (p = 0.032, hazard ratio 2.1), CIS, TP, and lack of BCG induction were significant for progression. CONCLUSIONS: TB is a new and significant pathological variable for predicting progression in HGT1 tumors and can be easily introduced in clinical practice. Its inclusion in the TNM system should be carefully considered, as it may aid early cystectomy decisions.