Expression and significance of Ku80 and PDGFR-α in nasal NK/T-cell lymphoma

Abstract

Background: To investigate the clinical and prognostic significance of Ku80 and PDGFR-α in nasal type NK/T cell lymphoma (NKTCL).

Methods: Immunohistochemistry for Ku80 and PDGFR-α was performed on tissue sections from 35 patients diagnosed with NKTCL. We analyzed the relationship between Ku80 and PDGFR-α expression and the clinicopathological features of NKTCL. We further performed multivariate analyses to identify prognostic factors for progression free survival (PFS) of patients.

Results: Ku80 expression rate in NKTCL was 94.3% compared with that in reactive lymphoid hyperplasia of nasopharynx (P=0.003). The positive expression rate of PDGFR-α in the group of NKTCL was 91.4% compared with that in control group (P=0.004). The positive correlation between Ku80 and PDGFR-α was also found (r=0.496, P=0.002). Ku80 and PDGFR-α expressions were not correlated with patient's gender, age, B symptoms, LDH, Ann Arbor stage, IPI score and treatment (P>0.05). High expression of Ku80 and PDGFR-α was shown to be correlated with worse PFS (P=0.003 and 0.034, respectively). Multivariate analysis with a Cox proportional hazards model further suggested that Ku80 high expression rate (HR, 11.495; P=0.009), PDGFR-α high expression rate (HR, 4.836; P=0.031) and International Prognostic Index (IPI) score of 3-4 (HR, 7.308; P=0.001) were statistically independent prognostic factors for patients' PFS. Our results suggest that Ku80 and PDGFR-α may be valuable indicators for predicting the survival of NKTCL patients.

Conclusion: Ku80 and PDGFR-α might be effective predictive indicators for the prognosis of NKTCL. A large prospective study is required to confirm the prognostic significance of Ku80 and PDGFR-α in NKTCL.

Keywords: Immunohistochemistry; Ku80; Nasal NK/T cell lymphoma; PDGFR-α.