Rhabdomyosarcoma: cytomorphology, subtyping and differential diagnostic dilemmas

To identify morphologic characteristics and architectural patterns of rhabdomyosarcoma (RMS), to attempt a subclassification from fine needle aspiration biopsy (FNAB) smears and to point out some differential diagnostic problems. STUDY DESIGN: We reviewed all positive cytologic material from 53 patients with RMS whose diagnoses were histologically and/or immunocytochemically confirmed. We analyzed several morphologic features and identified architectural patterns of smears. RESULTS: Among alveolar RMS, we identified two major architectural patterns: one containing completely dissociated cells and one containing many chance formations. Among the embryonal type, the predominant architectural pattern contained large tissue fragments with abundant eosinophilic material and various numbers of dissociated cells. The pattern of only dissociated cells was similar to the one seen in the alveolar type. The relative proportion of poorly to better and well-differentiated rhabdomyoblasts varied in both types and in all patterns. CONCLUSION: RMS exhibits a variety of morphologic pictures regarding cellular morphology and architectural patterns, even within the same histologic subtype. Therefore, a reliable subclassification into alveolar and embryonal RMS cannot be made from FNAB smears. The embryonal type can be suggested in cases containing large tissue fragments with abundant eosinophilic material and small, tightly packed cells with oval nuclei. However, all cases suspected to be RMS must always be confirmed immunocytochemically since they could be confused with some benign and malignant tumors with similar morphology

Usefulness of Bcl-2 Expression and the Expression of Cytoplasmic Immunoglobulin Light Chains in the Differentiation Between B-Cell Lymphoma and Reactive Lymphocytic Proliferations in FNA

Flow cytometry is helpful in differentiating between B-cell lymphoma (BCL) and reactive lymphocytic proliferation (RLP) in FNA biopsies. However; the presence of inconclusive surface immunoglobulin light chains (sIg LC) poses a problem. We investigated the usefulness of additional tests; namely Bcl-2 expression and expression of cytoplasmic Ig LC (cIg LC), mainly on samples with inconclusive sIg LC. Both tests were performed on 232 FNA samples from lymph nodes. Bcl-2 alone was determined qualitatively and quantitatively on 315 samples. The quantitative test was correctly positive in 76% of cases and falsely negative in 24%. The correctly positive results of the qualitative test were 11% points lower. cIg LC correctly identified 65% of BCL with dual positive sIg LC; 36% of BCL with difficult to interpret sIg LC and only 7% of BCL with negative sIg LC. The best results in differentiating between BCL and RLP were obtained when all three tests were used together. In samples with inconclusive sIg LC and additional monoclonal or polyclonal populations the κ:λ ratios did not differentiate between RLP and BCL. We propose that in case of inconclusive sIg LC Bcl-2 test is used first. The addition of cIg LC test is sensible only in cases with dual positive and difficult to interpret sIg LC

Cytology material is equivalent to tumor tissue in determining mutations of BRCA 1/2 genes in patients with tubo-ovarian high grade serous carcinoma

Abstract Background High-grade serous ovarian cancer is a detrimental disease. Treatment options in patients with a recurrent disease are dependent on BRCA1/2 mutation status since only patients with known BRCA mutation are eligible for treatment with poly(ADP-ribose) polymerase inhibitors (PARPi). The aim of this study was to compare concordance of BRCA mutation analyses from cytological samples (CS) with BRCA mutation analyses from histological formalin fixed paraffin embedded (FFPE) samples. Methods Mutation analysis of BRCA1 and BRCA2 genes was performed in 44 women diagnosed with primary or recurrent high-grade ovarian cancer from three different samples: blood, cytological sample (ascites, pleural effusion and enlarged lymph nodes) and tumor tissue. Results from all three samples were compared. Results Among 44 patients, there were 15 germline mutations and two somatic mutations. A 100% concordance was found between cytological and histologic samples. Conclusion There is a 100% concordance in BRCA mutation testing between cytological and histologic samples. BRCA mutation testing from CS could replace testing from FFPE tissue in clinical decision making in ovarian cancer patients. Trial registration The study was retrospectively registered at ISRCTN registry on 24/11/2015 - ISRCTN42408038

Clinical relevance of the borderline results of the Hybrid Capture 2 High-Risk HPV DNA assay with cervical samples collected in Specimen Transport Medium

The Hybrid Capture 2 (HC2) High-Risk HPV DNA assay serves as a triage test in the Slovenian national cervical cancer screening programme ZORA. To improve the limited analytical accuracy of HC2 test results near the cut-off value (1.0 relative light units/cut-off (RLU/CO)), we follow an internal protocol of repeating the test on all samples with borderline results within the 0.7-2.0 RLU/CO interval. The aim of the study was (i) to determine the clinical relevance of HC2 test results within three different “grey zones” for samples stored in Specimen Transport Medium (STM) and (ii) to determine whether the current algorithm of retesting “grey zone” STM specimens with the HC2 assay is clinically relevant

Evaluation of the training program for p16/ Ki-67 dual immunocytochemical staining interpretation for laboratory staff without experience in cervical cytology and immunocytochemistry

p16/Ki-67 dual immunocytochemical staining (DS) is considered easy to interpret if evaluators are properly trained, however, there is no consensus on what constitutes proper training. In the present study we evaluated a protocol for teaching DS evaluation on students inexperienced in cervical cytology