Relative frequency and survival of primary cutaneous lymphomas: a retrospective analysis of 98 patients

The World Health Organization and European Organization for Research and Treatment of Cancer (WHO-EORTC) classification in 2005 promoted the comparisons of primary cutaneous lymphoma (PCL) subtypes between different countries. The relative frequency of PCL varied according to geography. The study aimed to analyze the relative frequency and survival of PCLs in China and to compare the data with the published results from other countries.

We analyzed 98 patients with PCLs over a 6-year period and reclassified them according to the most recent WHO-EORTC classification (2005). Disease-specific survival rate and curves according to specific subtypes such as mycosis fungoides, lymphomatoid papulosis, and primary cutaneous peripheral T-cell lymphoma, unspecified was also calculated.

The relative rate of PCL in China was distinct from those in Western countries. Our study showed a higher frequency of cutaneous T- and NK-cell lymphomas (CTCLs) (94%), and a lower frequency of cutaneous B-cell lymphomas (CBCLs) (6%). The 5-year survival rate of the total PCLs was 82%. There was no significant difference in the 5-year survival rate (P > 0.05 by Log-rank test) between CTCL (80%) and CBCL (100%).

The higher percentage of CTCL in China may provide a clue to further study the etiological factors of PCLs. Racial variations in factors such as HLA determinants may play a role in the development of CTCL.