Incorporating microarray assessment of HER2 status in clinical practice supports individualised therapy in early-stage breast cancer.

Accurate determination of human epidermal growth factor receptor-2 (HER2) status is essential for optimal selection of breast cancer patients for gene targeted therapy. The analytical performance of microarray analysis using TargetPrint for assessment of HER2 status was evaluated in 138 breast tumours, including 41 fresh and 97 formalin-fixed paraffin embedded (FFPE) specimens. Reflex testing using immunohistochemistry/in situ hybridization (IHC/ISH) in four discordant cases confirmed the TargetPrint results, achieving 100% agreement regardless of whether fresh tissue or FFPE specimens were used. One equivocal IHC/ISH case was classified as HER2-positive based on the microarray result. The proven clinical utility in resolving equivocal and borderline cases justifies modification of the testing algorithm under these circumstances, to obtain a definitive positive or negative test result with the use of microarrays. Determination of HER2 status across three assay platforms facilitated improved quality assurance and led to a higher level of confidence on which to base treatment decisions.

The utilization of fine needle aspiration biopsy (FNAB) and flow cytometry (FC) in the diagnosis and classification of non-Hodgkin B-cell and T-cell lymphomas.

The subtypes of non-Hodgkin lymphomas may have similar morphology, but have a wide variation in origin, immunophenotype and biological features. Many ancillary investigations are available to help overcome these problems, including fine needle aspiration biopsy (FNAB) and flow cytometry (FC). FNAB coupled with FC can reliably distinguish between reactive and neoplastic lymphoid populations. It can be used in the diagnosis and classification of many lymphomas, obviating the need for surgical biopsy in a significant number of patients.

Fine needle aspiration biopsy and flow cytometry in the diagnosis of lymphoma.

UNLABELLED: Fine needle aspiration biopsy (FNAB) is emerging as a technique of potential value in the diagnosis of benign and malignant lesions in areas such as the breast and thyroid gland. Its place in distinguishing reactive from neoplastic lymphoid proliferations, when compared to the established practice of excision biopsy and histopathology, continues to undergo evaluation. Morphology alone discriminates poorly between atypical or lymphoproliferative disorders as seen in the presence of Epstein-Barr or human immunodeficiency virus. Furthermore the polymorphic populations of follicular lymphoma may mimic reactive changes. In addition previous classifications of these tumours using working formulation or Kiel classification relied heavily on architecture, which is a feature not reflected in cytology smears. The World Health Organisation approach includes clinical features, immunophenotyping and cytogenetic profiles to define neoplasms of immunohaematopoietic tissues. Flow cytometry on fine needle aspiration biopsy offers additional advantages in being rapid and objective in quantitatively as well as qualitatively documenting cell surface characteristics. All patients referred for this procedure to Tygerberg Academic Hospital with suspected nodal or extranodal lymphoma between January 2002 and December 2004 were analysed. In each case flow cytometry and cytomorphology were correlated with histopathology on tissue biopsy, bone marrow examination and clinical follow-up for confirmation of diagnosis. Results of the 124 cases were tabulated and statistically processed. Eighty-one met the inclusion criteria, thirteen (16.1%) were not malignant, two (2.5%) were falsely negative, two (2.5%) were equivocal needing histology and in the remaining sixty-four (79%) diagnosis was achieved. SUMMARY: Fine needle aspiration coupled with flow cytometry can reliably distinguish between nodal and extranodal neoplastic B-cell population. It is concluded that appropriate use, in a collaborative multidisciplinary setting, may eliminate the need for surgical procedures in many cases. CONCLUSION: These advances are not widely recognised and this is particularly true in South Africa. Accordingly, such an approach has been prospectively evaluated in the Western Cape showing that the combination of ready availability and diagnostic accuracy, after an initial learning curve, allow accurate characterisation of haematologic malignancies so that excision biopsy may be reserved for specific further studies to provide data not available from this less invasive procedure.