Immunohistochemical algorithms and gene expression profiling in primary cutaneous B-cell lymphoma.

OBJECTIVE: to assess whether immunohistochemical (IHC) algorithms used to classify the cell of origin (COO) of nodal Diffuse Large B-cell lymphoma (nDLBCL) in Germinal Center type (GCB) and non-GCB subtypes may be applied to Primary Cutaneous B-cell lymphoma (PCBCL) too, and which of these algorithms performs better on PCBCL. DESIGN: Retrospective case control study. SETTING: Pathology Department of the University Hospital "San Giovanni di Dio e Ruggi d'Aragona" Salerno, Italy. PARTICIPANTS: Fourteen PCBCL, including Primary Cutaneous follicle centre lymphoma (PCFCL) and primary cutaneous diffuse large B-cell lymphoma, Leg type (PCDLBCL-LT) and 14 nDLBCL were evaluated for 7-year period (January 2011 to December 2017). Primary cutaneous marginal zone cell lymphoma (PCMZL) cases were not included in the present study. INTERVENTION: Evaluation of immunohistochemical CD10, BCL6, MUM1/IRF4, BCL2, MYC and Ki-67 expression and classification according to three different algorithms. Gene expression profiling (GEP) was performed on the same series using Lymph2Cx assay (Nanostring). The data obtained were compared and analysed. RESULTS: All the IHC algorithms showed 13 GCB and 15 non-GCB. GEP showed 12 GCB, 12 activated B cell-type and 4 unclassified. CONCLUSIONS: The PCBCL were classifiable as GCB and non-GCB like the nDLBCL as IHC algorithms were concordant to GEP and produced the same results.

Advanced non-small cell lung cancer: Rapid evaluation of EGFR status on fine-needle cytology samples using Idylla.

Advanced non-small cell lung cancer (NSCLC) needs to be managed rapidly; therefore, a rapid assessment of the epidermal growth factor receptor (EGFR) status is mandatory. Computed Tomography (CT)-guided or Ultrasound (US)-guided Fine-Needle Aspiration Cytology (FNAC) allows a rapid diagnosis of both primary and metastatic tumor through rapid on-site evaluation (ROSE) and the proper management of diagnostic material. Idylla (Biocartis, Mechelen, Belgium) is an automated RT-PCR system which evaluates the mutational status of specific genes in less than two hours. In this study, the EGFR mutational status in advanced NSCLC was analyzed on 28 FNAC samples with Idylla. After ROSE, residual FNAC material and/or additional passes were pipetted into the Idylla EGFR cartridge. Patients endorsed a consent form before carrying out the analysis. Results were controlled by pyrosequencing. Adequate EGFR status was obtained in 26/28 cases (22 wild type and 4 mutated). Mutated cases harbored EGFR Exon 19 deletion and L858R point mutation. In 2/28 cases the analysis failed. The combination of FNAC, ROSE and Idylla is a rapid, accurate and effective method that can be conveniently used to assess EGFR status in advanced NSCLC.

Testing EGFR with Idylla on Cytological Specimens of Lung Cancer: A Review.

The current standard of care for advanced non-small-cell lung cancer is based on detecting actionable mutations that can benefit from targeted therapy. Comprehensive genetic tests can have long turn-around times, and because EGFR mutations are the most prevalent actionable mutation, a quick detection would enable a prompt initiation of targeted therapy. Furthermore, the scarcity of diagnostic material means that sometimes only cytologic material is available. The Idylla™ EGFR assay is a real-time PCR-based method able to detect 51 EGFR mutations in 2.5 h. Idylla is validated for use only on FFPE sections, but some researchers described their experiences with cytological material. We reviewed the relevant literature, finding four articles describing 471 cases and many types of cytological input material: smears, cell-block sections, suspensions, and extracted DNA. The sensitivity, specificity, and limit of detection appear comparable to those obtained with histological input material, with one exception: the usage of scraped stained smears as input may reduce the accuracy of the test. In conclusion, usage of cytological material as input to the Idylla EGFR test is possible. A workflow where common mutations are tested first and fast, leaving rarer mutations for subsequent comprehensive profiling, seems the most effective approach.