Application of immunohistochemistry to cytology.

Context: The uses of monoclonal antibodies via immunochemistry have been reported frequently within the literature using various methodologies with applications to cytology specimens. The direct application of immunochemistry to cytology may have a variety of pitfalls that the general pathologist familiar with its application to histology may be unaware of when applying it prospectively to patient specimens.

Objective: To review common pitfalls when applying immunochemistry to cytology specimens and to suggest approaches to the more common differential dilemmas that apply to a variety of cytology specimens that could be seen in a general pathology practice.

Accuracy and cost-effectiveness of core needle biopsy in the evaluation of suspected lymphoma: a study of 101 cases.

Context: Lymphomas have traditionally been diagnosed on excisional biopsies of lymph nodes in order to evaluate tissue architecture and cytomorphology. Recent lymphoma classification schemes emphasize immunophenotypic, genetic, and molecular aspects in addition to morphology as diagnostic features. Core needle biopsies are increasingly being used to obtain tissue for diagnosis in patients with lymphadenopathy and a clinical suspicion of lymphoma.