Neutrophil-to-Lymphocyte Ratio (NLR) and Platelet-to-Lymphocyte Ratio (PLR) as Possible Prognostic Markers for Patients Undergoing Resection of Adrenocortical Carcinoma

Abstract

Aim: Adrenocortical cancer (ACC) is a rare disease with a poor outcome, and robust prognostic factors remain unclear. High neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) as markers of host inflammation have been found to be associated with decreased long-term outcomes in several tumour types, but have been scarcely analysed in ACC.

Methods: Patients who underwent resection of their ACC between 2000 and 2020 were identified; therapeutic, operative and outcome data were analysed. Pre-operative NLR and PLR were calculated by division of neutrophils and platelets by lymphocytes measured in peripheral blood.

Results: Fifty-seven patients (30F:27 M) with an overall median age of 53 years [range: 18-86] presented with tumours of median size 11.5 cm [range: 3.0-22.0], of whom 26 (46%) were hormonally active. Majority of patients underwent an open resection (n = 48; 84%); more than half (n = 30; 53%) underwent multi-organ excision. Median NLR was 4.63 and median PLR was 186.21; these values were used for median split analyses (low vs. high). There were no differences with regard to age, sex or tumour characteristics and peri-operative data between the two groups (all p > 0.05). Overall, median recurrence-free survival (RFS) was 26 months (3-year: 45%) on Kaplan-Meier analysis. On univariate analyses, a high NLR did not influence RFS [HR = 1.57 (95%-CI: 0.73-2.38); p = 0.25], but patients with a high PLR had an increased risk of developing recurrence [HR = 2.39 (95%-CI: 1.08-5.31); p = 0.03]. The median overall survival (OS) was 33 months (3 years: 79%) on Kaplan-Meier analysis. Both a high NLR [HR = 2.24 (95%-CI: 1.07-4.70); p = 0.03] and a high PLR [HR = 4.02 (95%-CI: 1.80-8.98); p = 0.001] were strongly associated with a shorter OS on unadjusted analyses.

Conclusion: Elevated pre-operative NLR and PLR are associated with shorter OS, while higher PLR was also associated with a shorter RFS for patients undergoing curative intent resection of ACC.