MYD88 (L265P) mutation has garnered a lot of excitement because of its usefulness in diagnosing lymphoplasmacytic lymphoma (LPL). Traditionally, LPL has been difficult to diagnose because exclusion of other B-cell neoplasms with plasmacytic differentiation is required. MYD88 mutations are present in approximately 90% of cases of LPL, and in a much lower percentage of cases of B cell lymphomas, which are typically in the differential diagnosis of LPL.
MYD88 mutation frequency
- LPL ~ 90%
- DLBCL ~ 30% (non-germinal center)
- DLBCL >50% (primary cutaneous, leg type)
- Multiple myeloma – negative (even IgM subtype)
- CLL/SLL – 2-3%
- Extranodal marginal zone lymphoma – 7%
- Splenic marginal zone lymphoma – 4-15%
- Nodal marginal zone lymphoma – rare
References
Harmon CM, Smith LB. B-cell Non-Hodgkin Lymphomas with Plasmacytic Differentiation. Surg Pathol Clin. 2016;9: 11–28. doi:10.1016/j.path.2015.09.007
WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues. SH Swerdlow, et al. International Agency for Research on Cancer. Lyon, 2008. p. 194-195
Swerdlow SH, Campo E, Pileri SA, Harris NL, Stein H, Siebert R, et al. The 2016 revision of the World Health Organization classification of lymphoid neoplasms. Blood. 2016;127: 2375–2390. doi:10.1182/blood-2016-01-643569
Martinez-Lopez A, Curiel-Olmo S, Mollejo M, Cereceda L, Martinez N, Montes-Moreno S, et al. MYD88 (L265P) somatic mutation in marginal zone B-cell lymphoma. Am J Surg Pathol. 2015;39: 644–651. doi:10.1097/PAS.0000000000000411
Treon SP, Xu L, Yang G, Zhou Y, Liu X, Cao Y, et al. MYD88 L265P somatic mutation in Waldenström’s macroglobulinemia. N Engl J Med. 2012;367: 826–833. doi:10.1056/NEJMoa1200710