Low incidence of follicular lymphoma and t(14;18)(q32;q21) by polymerase chain reaction analysis: observations on Ecuadorian patients

Translocation (14;18)(q32;q21) has been shown to be present in diagnostic tissue specimens from approximately 85% of patients with follicular lymphoma (FL) and 30% with diffuse non-Hodgkin lymphomas (NHL) in the USA. Also, there is evidence that the distribution of NHL subtypes differs by geographic region; however, there are no data for Ecuador. Using polymerase chain reaction, we examined the frequency of t(14;18) (MBR and mcr rearrangements) in 65 NHL samples collected through 5 years from the principal hospitals of Quito, Ecuador. Of 65 NHL, only 5 were FL, which represents an incidence of 7.7%. This incidence is lower than observed in North America (30%). In addition, we did not find the t(14;18) in the samples analyzed, absence of which was confirmed by the use of a control. This suggests that this translocation is rare in NHL in Ecuador. These findings confirm that there are differences in the incidence of specific subtypes of NHL across some geographic areas and suggest that genetic factors may be responsible for the observed differences.