Extranodal Natural Killer/T-Cell Lymphoma Nasal Type in 87 Cases from Spain: Clinical Presentation, Treatment and Prognostic Factors. Study from the Geltamo Group
Authors: González-Barca Eva , Martín Alejandro , Bello Jose Luis , Bergua Burgues Juan Miguel Miguel , Panizo Carlos , Encuentra Maite , Monter Rovira Ana , Cordoba Raul , Bastos Mariana , Sanchez Blanco Jose Javier , Gomez Pilar , Marin Niebla Ana , González de Villambrosia Sonia , Sayas Maria Jose , Luzardo Henriquez Hugo Daniel , Viguria Alegria Maria De La Cruz , Sanchez-Gonzalez Blanca , Roig Monica , Perez De Oteyza Jaime , Cabezudo Elena , Escoda Lourdes , de Oña Raquel , Queizan Josë Antonio , Infante Maria Stefania , Muntañola Prat Ana , Lopez Andres 
Published: October 2019

Abstract
Introduction and Objective: Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKTL-NT) is associated with Epstein-Barr virus (EBV) and is much more common in Asia and Latin America than in western countries. Data on disease presentation and outcome from European series are very limited. The objective of the study is to analyze the clinical characteristics at diagnosis, treatment received and outcome of a series of patients from Spain.
Patients and Methods: Eigthy-seven patients with ENKTL-NT diagnosed from 2000 to 2017 were identified in 24 academic centers in Spain. Clinical data were collected retrospectively. Survival curves were estimated using the Kaplan-Meier method and compared using the log-rank test. Variables included in the univariate analysis were: race, gender, age, previous sinusitis, nasal localization, Ann Arbor stage, ECOG performance status (PS), B symptoms, LDH, beta2-microglobulin, albumin and C-reactive protein. Multivariate analyses were performed by Cox proportional hazard regression model.
Results: Clinical characteristics at diagnosis are shown in Table 1. Seventy-seven patients received active treatment, 31 (40%) with chemotherapy (CT) alone, 39 (51%) with CT and radiotherapy (RT), 7 (9%) with RT alone (median dose 50 Gy). First line therapies were: CHOP/CHOP-like in 30 (42%) patients, high-dose L-Asparaginase-containing regimens in 27 (38%), and other regimens in 14 (20%); 12 patients proceeded to stem-cell transplant in first line (10 auto / 2 allo). Response rate was evaluable in 70 patients (by PET/TC in 55%): CR 35 (50%), PR 9 (13%), SD/progression 26 (37%). Median number of CT lines was 2 (1-6). With a median follow-up of 38 months, 3 yr OS was 38% (95% CI 27-49), and 3 yr PFS 25% (95% CI 14-35). Causes of death were: progression 35 (67%), toxicity 12 (23%), second neoplasms 5 (10%). The variables at diagnosis significantly associated with poor OS were: age ≥ 60 yr, extranasal disease, Ann Arbor III-IV, ECOG PS 2-4, increased LDH, and decreased albumin. In the multivariate analysis including all the previous variables, ECOG 2-4 PS (HR 3.3, 95% CI 1.4-7.0) and low albumin (HR 3.6, 95% CI 1.4-9.3) maintained the negative influence in OS. Patients treated with regimens that included high dose L-Asparaginase had 3 yr OS of 61% (95%CI 40-82), compared with patients treated with CHOP/CHOP-like 3 yr OS of 19% (95%CI 5-32) (p=0.009). These differences were statistically significant both in patients with nasal involvement (3 yr OS 82% with L-Asparaginase vs 21% with CHOP, p=0.01) or with localized disease (3 yr OS 71% with L-Asparaginase vs 24% with CHOP, p=0.03). Differences were not statistically significant in patients with extranasal involvement (3 yr OS 48% with L-Asparaginase vs 14% with RCHOP, p=0.2), or advance disease (3 yr OS 48% with L-Asparaginase vs 14% with CHOP, p=0.2), probably because the low number of patients.
Conclusion: This is the largest series reported of Caucasian patients with ENKTL-NT. Patients are young at diagnosis and one fourth had a previous history of chronic sinusitis. This population has a poor outcome, being progression the main cause of death. Poor clinical condition at diagnosis (high ECOG PS and low albumin level) is the main factor related with poor survival. Therapies with high dose L-Asparaginase improve the survival in this western population compared with the classical CHOP regimen.

Disclosures
González-Barca: Roche: Speakers Bureau; Celtrion: Consultancy; Gilead: Consultancy; janssen: Consultancy, Speakers Bureau. Martín:Celgene: Consultancy, Honoraria, Other: Travel expenses; Roche: Consultancy, Honoraria, Other: Travel expenses; Janssen: Honoraria, Other: Travel expenses; Servier: Honoraria, Other: Travel expenses. Panizo:BMS: Membership on an entity's Board of Directors or advisory committees; Celgene: Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Acerta Pharma: Research Funding; Roche: Consultancy, Speakers Bureau. Sanchez Blanco:Gilead: Honoraria; Roche: Honoraria; Janssen: Honoraria. Marin Niebla:Roche: Consultancy, Other: Medical education of Staff, Speakers Bureau; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Medical education of Staff, Speakers Bureau; Celgene: Other: Medical education of Staff, Speakers Bureau; Amgen: Other: Medical education of Staff, Speakers Bureau. Queizan:Janssen: Consultancy. Lopez:Roche: Research Funding.