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.