Cytological preparations for molecular analysis: A review of technical procedures, advantages and limitations for referring samples for testing.

Minimally invasive procedures such as endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) must yield not only good quality and quantity of material for morphological assessment, but also an adequate sample for analysis of molecular markers to guide patients to appropriate targeted therapies. In this context, cytopathologists worldwide should be familiar with minimum requirements for refereeing cytological samples for testing. The present manuscript is a review with comprehensive description of the content of the workshop entitled Cytological preparations for molecular analysis: pre-analytical issues for EBUS TBNA, presented at the 40th European Congress of Cytopathology in Liverpool, UK. The present review emphasises the advantages and limitations of different types of cytology substrates used for molecular analysis such as archival smears, liquid-based preparations, archival cytospin preparations and FTA (Flinders Technology Associates) cards, as well as their technical requirements/features. These various types of cytological specimens can be successfully used for an extensive array of molecular studies, but the quality and quantity of extracted nucleic acids rely directly on adequate pre-analytical assessment of those samples. In this setting, cytopathologists must not only be familiar with the different types of specimens and associated technical procedures, but also correctly handle the material provided by minimally invasive procedures, ensuring that there is sufficient amount of material for a precise diagnosis and correct management of the patient through personalised care.

Use of cytological samples of metastatic melanoma for ancillary studies.

OBJECTIVE: Fine needle aspiration (FNA) is widely used in the diagnosis of metastatic melanoma, both at initial presentation and in the setting of recurrent disease. The purpose of this study was to evaluate the performance of confirmatory immunohistochemistry (IHC) and molecular analysis of the BRAF mutation in cytological preparations of metastatic melanoma. METHODS: A 2-year retrospective review of pathology reports was performed on cytological samples of metastatic melanoma at the University Health Network (Toronto, Canada) and the Santa Casa Medical School (Sao Paulo, Brazil). IHC was performed on cell block sections prepared from formalin-fixed, fresh samples or residuum of CytoLyt/PreservCyt post-fixed in formalin. BRAF V600E/K mutations were assessed by amplification refractory mutation system (ARMS) analysis. RESULTS: A total of 104 samples (94 FNAs and 10 fluids) from 83 patients (20 women, 63 men) were included. IHC was attempted in 43 cases (41.3%) and successful in 41 (95.3%). The panel number of antibodies ranged from 1 to 15 (median 3). The most frequently used melanoma markers included HMB-45, melanoma cocktail and S100 protein, used in 25 (58.1%), 23 (53.5%) and 18 samples (41.9%). Thirty cases (69.8%) used three or fewer markers. The BRAF V600E/K mutation was tested in eight samples, being successful in seven (87.5%) and positive in three (37.5%). CONCLUSIONS: Cytological samples are a reliable and sufficient source for IHC and subsequent molecular analysis, allowing a reduced diagnostic time and rapid, appropriate treatment options in patients with advanced melanoma.

Biomarker testing and time to treatment decision in patients with advanced nonsmall-cell lung cancer.

BACKGROUND: Testing for EGFR mutations and ALK rearrangement has become standard in managing advanced nonsmall-cell lung cancer (NSCLC). However, many institutions in Europe, North America and other world regions continue to face a common challenge of facilitating timely molecular testing with rapid result turnaround time. We assessed the prevalence of biomarker testing for advanced NSCLC patients and whether testing affected the timeliness of treatment decisions. METHODS: We conducted a retrospective chart review of a random sample of one-quarter of all patients with advanced NSCLC referred to the Princess Margaret Cancer Centre from 1 April 2010 to 31 March 2013. RESULTS: Of 300 patients reviewed, 175 seen by medical oncology had nonsquamous NSCLC, 72% of whom had biomarker testing carried out. Patients tested for biomarkers were more likely to be female (47% versus 21%, P = 0.002), Asian (27% versus 6%, P = 0.005) and never smokers (42% versus 8%, P < 0.0001). Only 21% of patients with biomarker testing had results available at their initial oncology consultation. This group had a shorter median time from consultation to treatment decision (0 versus 22 days, P = 0.0008) and time to treatment start (16 versus 29, P = 0.004). Thirteen percent underwent repeat biopsy for molecular testing after the initial consultation. Of those with positive EGFR or ALK results, 19% started chemotherapy before biomarker results became available. CONCLUSIONS: Awaiting biomarker testing results can delay treatment decisions and treatment initiation for patients with advanced NSCLC. This may be avoided by incorporating reflex biomarker testing into diagnostic algorithms for NSCLC at the level of the pathologist, and further education of specialists involved in obtaining diagnostic cancer specimens to ensure they are sufficient for molecular testing.

Epstein-Barr virus encoded RNA detected by in situ hybridization using cytological preparations.

OBJECTIVE: Detection of Epstein-Barr virus (EBV) status might help in the diagnosis of EBV-related neoplasms. The rate of successful assays for the detection of EBV-infected cells in cytological preparations has not been fully explored. Our aims were to examine the rate of successful in situ hybridization (ISH) assays for EBV-encoded RNA (EBER) in cytological specimens and to explore reasons for failure. METHODS: An electronic search selected cases with ISH-EBER assays performed on cytological preparations during a 10-year period. Data regarding patient age, gender and immune status, sample type and site, type of preparation, ISH-EBER results, immunophenotyping and immunohistochemistry results, final diagnosis and correspondent histopathological samples were retrieved. RESULTS: Sixty specimens from 58 patients with diagnoses of lymphoproliferative disorder (n = 35), carcinoma (n = 24) and sarcoma (n = 1) were identified. ISH-EBER assays were performed on 50 cell block sections and on 10 cytospin preparations, with 22 positive and 32 negative results. Six tests (four cytospins and two cell block sections) failed owing to loss of material during the assay and background staining, with an overall failure rate of 10% and 4% if cytospins were excluded. Assays were performed on 13 cytology and surgical specimens from the same site, with only one discrepant result. CONCLUSIONS: Cell block sections had more successful ISH-EBER assays when compared with cytospins. Reasons for failure were loss of material on the slide and background staining. A high concordance rate with surgical specimens emphasizes the usefulness of cytological samples for determining EBV status in patients with exhausted or no histological material available.

Cytomorphological and clinicopathological spectrum of pulmonary marginal zone lymphoma: the utility of immunophenotyping, PCR and FISH studies.

OBJECTIVE: To review cytomorphological criteria and clinicopathological findings in combination with ancillary tests for the specific diagnosis of pulmonary marginal zone lymphoma (MZL) in fine needle aspiration (FNA) specimens. METHODS: Cases of pulmonary MZL diagnosed using cytological specimens from 2005 to 2012 were retrieved and reviewed by three cytopathologists. Results of immunophenotypic analysis, interphase fluorescence in situ hybridization (FISH) and molecular assays were collated, together with clinical information and imaging data. Concurrent surgical biopsies were also retrieved. RESULTS: Fifteen lung FNA specimens were identified. The smears consisted predominantly of small centrocyte-like cells. Marked plasma cell differentiation was evident in 11 cases. All cases with slides available showed tissue fragments with lymphoid tangles (TFLTs). Multinucleated giant cells were present in nine cases, two of which showed granulomas. Immunophenotyping confirmed B-cell clonality in all cases. B-cell clonality was detected by polymerase chain reaction (PCR) in two samples. FISH identified MALT1 translocation in four of 10 cases tested and trisomy 3 in three of four cases. Concurrent surgical biopsies were diagnosed independently as MZL in seven cases. CONCLUSIONS: Cytology smears from lung FNA samples consisting of small lymphoid cells with a relative abundance of plasma cells or plasmacytoid cells and large TFLTs should prompt immunophenotyping and other ancillary studies, even if multinucleated giant cells and poorly formed granulomas are also identified. Specific diagnosis of pulmonary MZL in FNA samples can be rendered on the basis of morphological features coupled with the demonstration of B-cell clonality by immunophenotyping or PCR and cytogenetic abnormalities by FISH.

Inter- and intraobserver reproducibility of thyroid fine needle aspiration cytology: an analysis of discrepant cases.

OBJECTIVE: To determine the inter- and intraobserver reproducibility and analyse the discrepant cases of fine needle aspiration cytology (FNAC) of the thyroid. METHODS: Cases of thyroid FNAC with a corresponding histological diagnosis were reviewed regarding the original cytological diagnoses by two observers. The final cytological diagnoses (FCD) included both concordant and consensus diagnoses. The inter- and intraobserver reproducibility and efficacy of thyroid FNAC were calculated based on the FCD. RESULTS: A total of 97 FNAC cases with corresponding histopathological specimens were analysed. Although inter- and intraobserver disagreement in the cytological diagnoses occurred in about one-quarter of the cases analysed (24.7% and 23.7%, respectively), a substantial level of diagnostic interobserver (kappa = 0.71) and intraobserver (kappa = 0.66) reproducibility was observed. The efficacy of the method was 94.4%. Disagreement in the diagnosis was detected in 24 cases (24.7%), most of them (41.7%) for follicular lesions. Discordant cytological diagnoses between the two observers were represented by six (16.2%) of the 37 cases with an FCD of colloid nodule, five (41.7%) of the 12 cases of cellular follicular lesion, all three cases of follicular neoplasm, in two (6.3%) of the 32 cases of PTC, one (16.7%) of six cases of follicular neoplasm with a predominance of Hürthle cells and in one case of poorly differentiated neoplasia. Similarly, major disagreement in intraobserver cytological diagnoses was observed for the diagnosis of follicular lesions: 18 (78.3%) of a total of 23 discordant cases. CONCLUSION: As discrepancies in the cytopathological diagnosis can have repercussions in the management of patients, all cases with a cytological diagnosis of follicular lesions/neoplams should be reviewed in multidisciplinary meetings thus minimizing interobserver variability.

A clinicopathologic study of 196 intraoral minor salivary gland tumours.

We present a retrospective study of 196 patients with intraoral minor salivary gland tumours, 128 malignant and 68 benign, diagnosed from 1954 to 1993 in the A. C. Camargo Hospital, São Paulo, Brazil. Sixty-five percent of the cases occurred in the palate, followed by tongue (9.7%) and retromolar area (6.1%). Pleomorphic adenoma was the most common benign tumour, and mucoepidermoid carcinoma was predominant among the malignant tumours. Surgery was the main treatment method and postoperative radiotherapy and radiotherapy alone were used in 40 and 15 patients, respectively. Local recurrence was observed in two patients with pleomorphic adenoma and in eight patients with malignant tumours. Regional lymph node metastases occurred in four cases and distant metastases in five. Forty-six of 47 patients with benign tumours who were followed up from 1 to 7 years were alive without disease. Twenty-four of 79 patients with malignant tumours who were followed up for at least 5 years died due the tumour and 47 were alive without disease.