Primary diagnosis and REAL/WHO classification of non‐Hodgkin's lymphoma by fine‐needle aspiration: Cytomorphologic and immunophenotypic approach

Abstract

The Revised European American lymphoma (REAL) and World Health Organization (WHO) classification of non-Hodgkin's lymphoma (NHL) relies on the constellation of cytologic, phenotypic, genotypic, and clinical characteristics of NHL. For the most part, the classification does not rely on architectural pattern for classification of neoplasms. This classification makes it possible to diagnose and classify lymphomas by fine-needle aspiration (FNA). In this study, we attempted to evaluate the accuracy of FNA in diagnosing and classifying NHL within the context of the REAL/WHO classifications. Cases included only those in which FNA was the primary diagnosis, followed by a surgical biopsy for confirmation. Flow cytometry (FCM) for phenotyping was carried out whenever material was available. Two groups of pathologists were identified. Group A consisted of pathologists with background training in cytopathology and/or hematopathology (three pathologists). Group B consisted of experienced surgical pathologists with no training in cytopathology and/or hematopathology (four pathologists). Seventy-four cases were included in the study. FCM phenotyping was performed in 53 cases (71%). Large cell lymphoma constituted 63% of the cases. The remaining lymphomas included Burkitt's, small lymphocytic, lymphoblastic, follicle center cell, Ki-1, mantle cell, marginal zone, and natural killer cell lymphoma. The diagnosis of lymphoma was rendered for all cases. The correct classification was seen in 63% of the cases. Classification was more accurate in immunophenotyped than in nonimmunophenotyped cases (84% vs 33%; P = 0.00004). Group A pathologists showed higher incidence of proper classification than group B (80% vs 56%; P = 0.046). The diagnosis and classification of NHL can be achieved in a large number of cases on FNA material. This accuracy can be increased if cytomorphologic criteria are established for different entities of NHL aided by FCM for phenotyping.

Tissue flow cytometry immunophenotyping in the diagnosis and classification of non‐Hodgkin's lymphomas: A retrospective evaluation of 1,792 cases

“…Several studies have demonstrated the usefulness of FC in diagnosing lymphoma by means of fine needle aspiration (FNA) cytology as well as in staging and follow-up (18)(19)(20)(21)(22)(23)(24). However, only few reports are available regarding the role of FC in tissue diagnosis of lymphoma (25)(26)(27)(28)(29)(30)(31), and literature mainly reports tissue FC studies in selected lymphoma subtypes (12,14,(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48).…”

Lymph Node Fine-Needle Cytology of Non-Hodgkin Lymphoma: Diagnosis and Classification by Flow Cytometry

“…However, such classification can be performed in several cases by combining cytological features with FC profiles [4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23]. On the basis of CD5/CD10 expression, lymphoid populations can be divided into 4 groups: CD10+/CD5-; CD10-/CD5+; CD10-/CD5-, and CD10+/CD5+ [3].…”

“…The sensitivity and specificity of lymph node FNC for the diagnosis and classification of NHL, combined with FC, range from 75 [4] to 99% [5] and from 87 [6] to 100% [4,7,8,9,10,11,12,13,14,15,16], respectively [17,18,19]. According to these data, lymph node FNC/FC has a high sensitivity and specificity in the distinction between reactive and lymphomatous proliferations but a variable degree of accuracy in terms of NHL classification (table 1).…”

Importance of Flow Cytometry in the Cytopathologic Evaluation of Lymphoid Lesions Involving the Kidney

“…Newer techniques such as immunophenotyping, cytogenetics and molecular studies, however, have opened promising avenues for the initial diagnosis of NHL on small samples [7,8,9,10,11], and numerous studies performed over the past 20 years have shown FNA to have both a high sensitivity and specificity in the diagnosis of NHL when used with ancillary techniques [12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29]. When FNA cytomorphology is combined with FC on a sample from any organ and the findings are compared with follow-up surgical specimens, diagnostic sensitivity and specificity have been reported as high as 97 and 94%, respectively [6].…”