Comparative Evaluation of Bone Marrow Aspirate with Trephine Biopsy in Hematological Disorders and Determination of Optimum Trephine Length in Lymphoma Infiltration

INTRODUCTION Bone marrow examination is an indispensable diagnostic tool to evaluate neoplastic and non neoplastic hematological diseases. AIMS To compare bone marrow aspirate with trephine biopsy in hematological disorders. To determine the optimum trephine preprocessing length in lymphoma infiltration. METHODS Diagnostic comparison was done between simultaneous bone marrow aspirates and trephine biopsies in 449 patients. Biopsies were fixed in formalin, decalcified in 5.5% EDTA and routinely processed. Concordance rates and validity parameters for aspirate were calculated. Three deeper sections of trephine biopsy, cut at 0.1-0.2 mm intervals, were assessed for lymphoma involvement. Proportion of biopsies showing marrow infiltration by lymphoma cells was plotted against trephine length and correlation was assessed. RESULTS Aspirate had a high sensitivity for acute leukemia (89.4%) and multiple myeloma (88.5%), moderate for NHL (67.6%) and nonhematopoietic metastases (58.3%) and low for aplastic anemia (38.5%) and Hodgkin lymphoma (5%). Aspirate has no role in granulomatous myelitis and myelofibrosis. Lymphoma positivity increased with trephine length, with maximum positivity (68.9%) seen in 17-20 mm group and no further gain beyond 20 mm. (lymphoma positivity ≤16mm=40.3% and ≥17mm=66.1%, p=0.0011). CONCLUSION Aspirate has a high specificity; its sensitivity depends upon the type of disease. Apart from few conditions, in which aspirate alone is sufficient, biopsy is mandatory in most. Preprocessing trephine length of 17-20 mm examined at multiple deeper levels was found optimal for assessing lymphoma positivity.