Objective To analyze the effect of minimum absolute lymphocyte counts (Min ALC) on progression free survival (PFS) in patients with locally advanced nasopharyngeal carcinoma during concurrent chemoradiotherapy.

Methods A total of 53 patients with locally advanced nasopharyngeal carcinoma who underwent radical concurrent chemoradiotherapy were retrospectively analyzed. According to the analysis of receiver operating characteristic (ROC) curve, the patients were divided into high Min ALC group and low Min ALC group. The effect of Min ALC on PFS in patients was analyzed, and the influencing factors associated with PFS in patients were discussed.

Results Binary logistic regression analysis showed that Min ALC during treatment had a statistically significant effect on patient PFS (P＜0.01). Survival analysis showed that the 12-month PFS rate in the high Min ALC group (85%) was not significantly different from that in the low Min ALC group (68%) (P ＞ 0.05); whereas the 24- and 48-month PFS rates in the high Min ALC group (83% and 79%, respectively) were significantly higher than those in the low Min ALC group (42% and 38%, respectively) (P ＜ 0.05). The median PFS was not followed up in the high Min ALC group, whereas it was 20 months in the low Min ALC group. Both univariate and multivariate analyses identified low Min ALC as a risk factor for disease progression (P ＜ 0.01).

Conclusions Min ALC is an independent influencing factor for PFS in patients with locally advanced nasopharyngeal carcinoma, and patients with lower Min ALC have shorter PFS during treatment.