Utilization of polymerase chain reaction on archival cytologic material: a comparison with fresh material with special emphasis on cerebrospinal fluids

Diagnosis of anaplastic lymphoma kinase rearrangement in cytological samples through a fluorescence in situ hybridization-based assay: Cytological smears versus cell blocks

Anaplastic lymphoma kinase (ALK) status analysis of lung cytological specimens should be successfully encouraged in routine practice because biopsy specimens are not always available. To date, the US Food and Drug Administration has approved both fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) as diagnostic tests for identifying ALK-positive patients eligible for treatment with crizotinib. Although ALK IHC is an optimal diagnostic tool, FISH becomes mandatory in equivocal cases. ALK FISH of paraffin-embedded tissue material is still the gold standard, whereas the cytological specimen assay has not yet been completely standardized. Many controversial data have been reported on the adequacy of cytology cell blocks (CBs) versus conventional smears for FISH testing. This review discusses some critical issues related to ALK FISH of cytological samples, including the triaging of collected specimens to optimize the material, the use of CBs versus conventional smears, and alternative methods for an ALK rearrangement diagnosis. Conventional smears have the advantages of an immediate evaluation, no probe tissue-related artifactual loss, no fixation-related alterations, and usually sufficient material for an analytic preparation. On the other hand, CBs have several advantages, including the appropriate conservation of the tissue architecture, an absence of problems related to cell overlapping, and the ability to evaluate neoplastic cells in a dark field. Cancer Cytopathol 2017;125:303-312. © 2017 American Cancer Society.

Optimizing nucleic acid extraction from thyroid fine-needle aspiration cells in stained slides, formalin-fixed/paraffin-embedded tissues, and long-term stored blood samples

OBJECTIVE: Adequate isolation of nucleic acids from peripheral blood, fine-needle aspiration cells in stained slides, and fresh and formalin-fixed/paraffin-embedded tissues is crucial to ensure the success of molecular endocrinology techniques, especially when samples are stored for long periods, or when no other samples can be collected from patients who are lost to follow-up. Here, we evaluate several procedures to improve current methodologies for DNA (salting-out) and RNA isolation. MATERIALS AND METHODS: We used proteinase K treatment, heat shock, and other adaptations to increase the amount and quality of the material retrieved from the samples. RESULTS: We successfully isolated DNA and RNA from the samples described above, and this material was suitable for PCR, methylation profiling, real-time PCR and DNA sequencing. CONCLUSION: The techniques herein applied to isolate nucleic acids allowed further reliable molecular analyses. Arq Bras Endocrinol Metab. 2012;56(9):618-26

Archival fine-needle aspiration cytopathology (FNAC) samples: untapped resource for clinical molecular profiling

Microarray technologies provide high-resolution maps of chromosome imbalances and epigenomic aberrations in the cancer cell genome. Such assays are often sensitive to sample DNA integrity, voiding the utility of many archival pathology specimens and necessitating the special handling of prospective clinical specimens. We have identified the remarkable preservation of higher-molecular weight DNA in archival fine-needle aspiration cytopathology specimens from patients greater than 10 years of age. We further demonstrate the outstanding technical performance of 57 fine-needle aspiration cytopathology samples for aberration detection on high-resolution comparative genomic hybridization array, DNA methylation, and single nucleotide polymorphism genotyping platforms. Forty-four of 46 malignant aspirates in this study manifested unequivocal genomic aberrations. Importantly, matched Papanicolaou and Diff-Quik fine-needle aspiration cytopathology samples showed critical differences in DNA preservation and DNA integrity. Overall, this study identifies a largely untapped reserve of human pathology specimens for molecular profiling studies, with ramifications for the prospective collection of clinical biospecimens.

Cytologic evaluation of lymphadenopathy associated with mycosis fungoides and Sezary syndrome: role of immunophenotypic and molecular ancillary studies

BACKGROUND

The most common presenting site of extracutaneous disease in mycosis fungoides and Sezary syndrome is the peripheral lymph node. Although fine-needle aspiration biopsy has been shown to be a valuable diagnostic technique in evaluating lymphadenopathy, its utility in patients with cutaneous T-cell lymphoma has not been extensively studied. With fine-needle aspiration biopsy, material can be collected for ancillary diagnostic studies and for morphologic evaluation.

METHODS

The authors report a series of 11 fine-needle aspiration biopsy specimens from 10 mycosis fungoides and Sezary syndrome patients. Flow cytometric immunophenotyping and T-cell receptor gamma chain polymerase chain reaction were performed on fine-needle aspiration biopsy material and correlated with cytologic findings.

RESULTS

Seven of 10 patients had lymph node involvement by cutaneous T-cell lymphoma, with 3 cases exhibiting large-cell transformation and 4 cases exhibiting a small-cell pattern. Flow cytometric immunophenotyping identified an abnormal T-cell population in 6 cases. A clonal T-cell rearrangement by T-cell receptor gamma chain polymerase chain reaction (TCR-gamma PCR) was identified in 1 case in which insufficient events were present for evaluation by flow cytometry and in 1 case in which flow cytometry was not diagnostic of T-cell lymphoma. Two cases showed involvement by classic Hodgkin lymphoma diagnosed by immunohistochemistry on cell block material.

CONCLUSIONS

Fine-needle aspiration biopsy in conjunction with immunophenotyping and T-cell receptor gamma chain polymerase chain reaction is significantly useful in evaluation of lymphadenopathy in patients with mycosis fungoides and Sezary syndrome, especially for triaging lymph nodes that would otherwise not be sampled or for evaluating multiple lymph nodes.

Detection of malignant hematopoietic cells in cerebral spinal fluid previously diagnosed as atypical or suspicious

BACKGROUND

Involvement of the cerebrospinal fluid (CSF) by hematopoietic malignancies may be difficult to document by morphology alone. In cases with low numbers of cells or ambiguous morphology, the diagnoses of "atypical" or "suspicious" may be used. The significance of these diagnostic terms in this scenario has not been well established.

METHODS

Between January 2000 and July 2004, 32 patients with known lymphoma or leukemia and an initial diagnosis of "atypical" or "suspicious" using morphologic criteria were identified. Subsequent flow cytometry (FC) and cytologic data from these patients were evaluated.

RESULTS

Of the 32 patients with an initial diagnosis of "atypical" or "suspicious," 40.6% (n = 13) had negative first and subsequent FC and morphologic evaluation of their CSF samples with follow-up up to 1 year. Nineteen patients (59.4%) had malignant hematopoietic cells identified in subsequent CSF samples by cytology and/or FC.

CONCLUSIONS

In patients with a previous history of lymphoma or a hematopoietic malignancy, a majority of the patients (59.4%) with an "atypical" or "suspicious" diagnosis on CSF will ultimately have malignant cells identified in the CSF by cytology and/or FC. Many of these patients can be identified more expediently with the concurrent utilization of flow cytometry.