- Anamarija M. Perry1,
- Jacques Diebold2,
- Bharat N. Nathwani3,
- Kenneth A. MacLennan4,
- Hans K. Müller-Hermelink5,
- Martin Bast6,
- Eugene Boilesen6,
- James O. Armitage6 and
- Dennis D. Weisenburger7,*
- 1 University of Manitoba;
- 2 Hotel-Dieu, University Denis Diderot;
- 3 City of Hope National Medical Center;
- 4 St. James University Hospital;
- 5 University of Würzburg;
- 6 University of Nebraska Medical Center;
- 7 City of Hope
- ↵* Corresponding author; email:
The distribution of non-Hodgkin lymphoma subtypes varies around the world, but a large systematic comparative study has never been done. In this study, we evaluated the clinical features and relative frequencies of non-Hodgkin lymphoma subtypes in five developing regions of the world and compared the findings to the developed world. Five expert hematopathologists classified 4848 consecutive cases of lymphoma from 27 centers in 25 countries using the World Health Organization classification and 4539 (93.6%) were confirmed to be non-Hodgkin lymphoma, with a significantly greater number of males in the developing regions compared to the developed world (p<0.05). The median age at diagnosis was significantly lower for both low- and high-grade B-cell lymphoma in the developing regions. The developing regions had a significantly lower frequency of B-cell lymphoma (86.6%) and a higher frequency of T- and NK-cell lymphoma (13.4%) compared to the developed world (90.7% and 9.3%, respectively). Also, the developing regions had significantly more cases of high-grade B-cell lymphoma (59.6%) and fewer cases of low-grade B-cell lymphoma (22.7%) compared to the developed world (39.2% and 32.7%, respectively). Among the B-cell lymphomas, diffuse large B-cell lymphoma was the most common subtype (42.5%) in the developing regions. Burkitt lymphoma (2.2%), precursor B- and T-lymphoblastic leukemia/lymphoma (1.1% and 2.9%) and extranodal NK/T-cell lymphoma (2.2%) were also significantly increased in the developing regions. These findings suggest that differences in etiologic and host risk factors are likely responsible and more detailed epidemiologic studies are needed to better understand these differences.
- Received May 4, 2016.
- Accepted June 23, 2016.
- Copyright © 2016, Ferrata Storti Foundation