EBV Is Infrequently Expressed in the LP Cells of Nodular Lymphocyte Predominant Hodgkin Lymphoma (NLPHL) in Both Children and Adults
Alina Nicolae, Alison R Huppmann, Graham W Slack, Judith A Ferry, Nancy Lee Harris, Stefania Pittaluga, Elaine S Jaffe, Robert P Hasserjian. National Cancer Institute, Bethesda, MD; BC Cancer Agency, Vancouver, Canada; Massachusetts General Hospital, Boston, MA
Background: NLPHL differs from classical Hodgkin lymphoma (CHL) in morphology and immunophenotype. EBV is detected in the neoplastic cells of 25-70% of CHL but prevalence in NLPHL is largely unknown. We assessed EBV status in 301 pediatric and adult cases of NLPHL.
Design: 145 pediatric (age ≤18) and 156 adult cases of NLPHL were retrieved from the archives of three North American centers and tested for EBV by in situ hybridization (EBER). Available clinical, histologic and immunophenotypic features were analyzed. The immunohistochemical panel included: CD20, CD3, CD15, CD30, CD79a, PAX5, Oct-2, Bob1, BCL6, MUM1, PD-1, CD57, EMA, IgD and CD21.
Results: NLPHL affected predominantly males, with a higher M:F ratio in children (10:1) than adults (3.2:1)(p=0.0005). NLPHL in children presented more commonly in cervical (p<0.0001) and less commonly in axillary (p<0.0001) or intra-abdominal (p=0.001) LNs than in adults. Five (3.44%) pediatric and 6 (3.84%) adult NLPHL cases contained EBV+ LP cells; EBER was positive in most or all of the LP cells in all cases. 2 EBV+ pediatric cases originated from Saudi Arabia and Paraguay, with the remainder from North America. Oct-2 and CD20 were strongly expressed and BCL6 and/or CD79a at least focally positive in the LP cells of all EBV+ cases. Pleomorphic and clustered LP cells were noted in 6/11 EBV+ cases, and focal or weak CD30 expression in LP cells was more common in EBV+ (9/11, 82%) than EBV- (66/258, 26%) NLPHL (p=0.0002), but CD15 was consistently negative. The histologic patterns and cellular composition of the background did not differ between EBV+ and EBV- cases. Pediatric NLPHL were more likely to express IgD in LP cells (88/125 pediatric versus 32/83 adult cases, p<0.0001); no NLPHL cases in patients >25 years had IgD+ LP cells. IgD was expressed in the LP cells in 2/5 EBV+ pediatric cases.
Conclusions: EBV was found in LP cells of NLPHL in 3.65% of pediatric and adult cases. This incidence is lower than that reported for NLPHL in developing countries [50% (25-100%) based on literature review]. Partial expression of CD30 and pleomorphism of LP cells can make the distinction from lymphocyte-rich CHL challenging. Expression of CD20, Oct-2, BCL6 and CD79a supports the diagnosis of NLPHL in the EBV+ cases.
Monday, March 4, 2013 1:00 PM
Poster Session II # 211, Monday Afternoon