title: Lymphopenia during routine follow-up may predict relapse in patients with extranodal NK/T cell lymphoma.
abstract: Recently, absolute lymphocyte count (ALC) at diagnosis, as a surrogate marker of host immunity, has been reported to be a prognostic factor for clinical outcomes in extranodal NK/T cell lymphoma (ENKTL). In this retrospective study, we set out to investigate whether ALC at the time of confirmed relapse or at last follow-up is a marker for relapse after chemoradiotherapy in 84 patients with stage I/II ENKTL. Receiver operating characteristics (ROC) curve and area under the curve (AUC) analysis showed that ALC at follow-up was a significant marker for relapse (AUC = 0.883, P < 0.001). Using 1.215 × 10(9)/L as the optimal cutoff value of ALC, 44 patients (52.4%) were in lower ALC group and 40 patients (47.6%) were in higher ALC group. The sensitivity and specificity for ALC at the time of confirmed relapse or at last follow-up was 94.1 and 76.0%, respectively. The relative risk of relapse with an ALC < 1.215 × 10(9)/L was 14.5. The positive predictive value with an ALC < 1.215 × 10(9)/L was 72.7%, and the negative predictive value with an ALC ≥ 1.215 × 10(9)/L was 95.0%. The 4-year cumulative incidence rate for an ALC < 1.215 × 10(9)/L was 73.2% compared with 3.2% for an ALC ≥ 1.215 × 10(9)/L (P < 0.001). In a multivariate regression analysis, ALC at the time of confirmed relapse or last follow-up remained to be a significant factor for relapse (P < 0.001). In conclusion, lymphopenia observed during routine follow-up can predict relapse in patients with ENKTL, which needs further validation in prospective trials.
authors.affiliation: Department of Hematological Oncology, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, People's Republic of China.
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.forename: Jing-hua
authors.initials: JH
authors.lastname: Wang
authors.forename: Zhi-jun
authors.initials: ZJ
authors.lastname: Wu-Xiao
authors.forename: Zhong-jun
authors.initials: ZJ
authors.lastname: Xia
authors.forename: Hui-qiang
authors.initials: HQ
authors.lastname: Huang
authors.forename: Yue
authors.initials: Y
authors.lastname: Lu
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D019540:Area Under Curve; D014408:Biomarkers, Tumor / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D054391:Lymphoma, Extranodal NK-T-Cell / Q000188:drug therapy / Q000473:pathology*; D008231:Lymphopenia / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D012372:ROC Curve; D012189:Retrospective Studies; D012306:Risk; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor