Hodgkin's disease in Mexico. Prevalence of Epstein-Barr virus sequences and correlations with histologic subtype.

BACKGROUND

The Epstein-Barr virus (EBV) has been linked to several human malignancies, including Hodgkin's disease (HD). In addition, epidemiologic studies have shown differences in HD occurrence in different parts of the world. The authors studied 27 cases of Hodgkin's disease from Mexico to determine the prevalence of EBV in HD in this developing nation.

METHODS

The Epstein-Barr virus was investigated using in situ hybridization with the EBER1 probe. Immunohistochemical studies were performed on paraffin sections. Cases from both adult and pediatric age groups were included. Correlations with histologic subtype, clinicopathologic features, and immunophenotype were determined.

RESULTS

Epstein-Barr virus sequences were identified in 18/27 (67%) cases. Positivity correlated with histologic subtype: 0/1 lymphocyte predominant; 6/13 (46%) nodular sclerosis; 7/7 mixed cellularity (MC) (100%); and 5/6 (83%) lymphocyte depleted (LD). The proportion of cases classified as MC and LD (13 of 27) was greater than that found in the United States and other developed countries. The immunophenotypic profile was appropriate for Hodgkin's disease, with all cases of classic Hodgkin's disease positive for CD30 (Ber-H2) and 18 cases expressing CD15. One case of lymphocyte-predominant Hodgkin's disease was CD20 (L26)-positive as were three cases of classic Hodgkin's disease. Patient age ranged from 5 to 65 years, with a median of 29 years.

CONCLUSIONS

The EBV is associated highly with HD in Mexico, and this prevalence rate is found in all age groups. A strong correlation between EBV expression and histologic subtype was confirmed, with 92% of MC and LD subtypes found to be positive.