Absolute lymphocyte count is a novel prognostic indicator in extranodal natural killer/T-cell lymphoma, nasal type.

BACKGROUND

extranodal natural killer (NK)/T-cell lymphoma (ENKL) is a heterogeneous entity with poor survival, requiring risk stratification in affected patients. We proposed absolute lymphocyte count (ALC) as a new prognostic factor in ENKL.

PATIENTS AND

METHODS

we retrospectively analyzed 128 patients newly diagnosed with ENKL. Independent prognostic factors of survival were determined by Cox regression analysis.

RESULTS

patients with low ALC (<1.0 × 10(9)/l) at diagnosis tended to have more adverse clinical features. Patients with high ALC (≥1.0 × 10(9)/l) at diagnosis had better overall survival (OS; P < 0.0001) and progression-free survival (PFS; P<0.0001), and achieved higher complete remission rates (P=0.001). Multivariate analysis with known prognostic factors showed that ALC, B symptoms and advanced stage were independent predictors for OS and PFS. Using the International Prognostic Index, Prognostic Index for Peripheral T-cell lymphoma unspecified, or Korean Prognostic Index for nasal NK/T-cell lymphoma, the majority of patients were in the low-risk category (with no or one adverse factor). ALC was helpful to differentiate the low-risk patients with different survival outcomes (P < 0.0001).

CONCLUSIONS

our data suggest that ALC at diagnosis is a novel, powerful predictor of prognosis in ENKL. Immune status at diagnosis might have an important influence on survival in patients with ENKL.