Abstract
BACKGROUND: Severe lymphopenia during treatment is considered to be a poor prognostic factor. The current literature lacks information regarding its impact on various outcomes in locally advanced head-and-neck cancer patients in a prospective setting. METHODS: We recently published a randomised study comparing cisplatin-radiation with nimotuzumab cisplatin-radiation. The database of this study was used for the present analysis. The impact of severe lymphopenia (grade 4 lymphopenia) on progression-free survival (PFS), locoregional control (LRC) and overall survival (OS) was studied using the Kaplan-Meier method and Cox regression analysis. The binary logistic regression analysis was used to see the effect of various factors on the development of severe lymphopenia. RESULTS: We had a total of 536 patients, of which 521 patients (97.7%) developed lymphopenia. Grade 1 lymphopenia was noted in 10 (1.9%) patients, grade 2 in 100 (18.8%), grade 3 in 338 (63.1%) and grade 4 in 73 (13.7%) patients. The median PFS was 20.53 and 60.33 months in severe and non-severe lymphopenia, respectively (hazard ratio, 0.797; p-value = 0.208). The median duration of LRC was 56.3 months in severe lymphopenia, whereas it was not reached in non-severe lymphopenia (hazard ratio, 0.81; p-value = 0.337). The median OS was 28.46 versus 47.13 months in severe and non-severe lymphopenia, respectively (hazard ratio, 0.76; p-value = 0.11). Of various risk factors, gender was significantly associated with severe lymphopenia. CONCLUSION: The occurrence of severe lymphopenia was not significantly associated with the outcomes. Gender is the only risk factor significantly linked to severe lymphopenia.