Context.—The need for appropriate specimen use for
ancillary testing has become more commonplace in the
practice of pathology. This, coupled with improvements in
technology, often provides less invasive methods of testing,
but presents new challenges to appropriate specimen
collection and handling of these small specimens, including thoracic small biopsy and cytology samples.
Objective.—To develop a clinical practice guideline
including recommendations on how to obtain, handle, and
process thoracic small biopsy and cytology tissue specimens for diagnostic testing and ancillary studies.
Methods.—The College of American Pathologists convened an expert panel to perform a systematic review of the
literature and develop recommendations. Core needle
biopsy, touch preparation, fine-needle aspiration, and
effusion specimens with thoracic diseases including malignancy, granulomatous process/sarcoidosis, and infection (eg,
tuberculosis) were deemed within scope. Ancillary studies
included immunohistochemistry and immunocytochemistry,
fluorescence in situ hybridization, mutational analysis, flow
cytometry, cytogenetics, and microbiologic studies routinely
performed in the clinical pathology laboratory. The use of
rapid on-site evaluation was also covered.
Results.—Sixteen guideline statements were developed to
assist clinicians and pathologists in collecting and processing thoracic small biopsy and cytology tissue samples.
Conclusions.—Based on the systematic review and
expert panel consensus, thoracic small specimens can be handled and processed to perform downstream testing (eg,
molecular markers, immunohistochemical biomarkers),
core needle and fine-needle techniques can provide
appropriate cytologic and histologic specimens for ancillary studies, and rapid on-site cytologic evaluation remains
helpful in appropriate triage, handling, and processing of
specimens.