THE VALUE OF IMMUNOHISTOCHEMISTRY
IN THE ASSESSMENT OF BONE MARROW DISORDERS

Attilio Orazi, M.D., FRCPath. and Dennis P. O'Malley, M.D.

CYCLIN D1 The most specific marker available for identifying mantle cell lymphoma. Cyclin D1 positive immunostaining identifies about 70% of cases of mantle cell lymphoma. Rare cases of atypical chronic B cell lymphocytic leukemia and hairy cell leukemia can also express cyclin D1. Expression of cyclin D1 can be seen in multiple myeloma. This protein can also be successfully demonstrated in the bone marrow by using an heat induced epitope retrieval procedure (Vasef et al, 1997). The immunostaining is very useful in distinguishing manlte cell lymphoma from other low grade lymmphoproliferative conditions encountered in the bone marrow. References Vasef et al: Cyclin D1 immunohistochemical staining is useful in distinguishing mantle cell lymphoma from other low-grade B-cell neoplasms in bone marrow. Am J Clin Pathol. 1997;108:302-7. Yang et al: Cyclin D1 (Bcl-1, PRAD1) protein expression in low-grade B-cell lymphomas and reactive hyperplasia. Am J Pathol. 1994; 145:86-96.