Systematic review of the effectiveness of fine-needle aspiration and/or core needle biopsy for subclassifying lymphoma

The World Health Organization system for lymphoma classification relies on histologic findings from excisional biopsies. In contradistinction to expert guidelines, practitioners increasingly rely on fine-needle aspiration cytology and core needle biopsies rather than excisional biopsies to diagnose lymphomas. To determine a rate at which fine-needle aspiration cytology and core needle biopsies, combined with flow cytometry and/or genetic techniques, can provide a diagnosis sufficient for optimal medical management of lymphoma. The English-language literature on fine-needle aspiration cytology and core needle biopsies for lymphoma was reviewed to identify studies that provided interpretations of all specimens regardless of whether these were deemed diagnostic. Forty-two studies (1989-2012) specified the lymphoma subtypes for each diagnosis or indicated a rate at which the methods failed to provide a diagnosis. The median rate at which fine-needle aspiration cytology and core needle biopsies yielded a subtype-specific diagnosis of lymphoma was 74%. Strictly adhering to expert guidelines, which state that follicular lymphoma cannot be graded by these techniques, decreased the diagnostic yield further to 66%. Thus, 25% to 35% of fine-needle aspirates and/or core biopsies of nodes must be followed by an excisional lymph node biopsy to fully classify lymphoma.