Beyond Platelet Count: Chemotherapy Drives Platelet Index Alterations Independent of Cancer Type

Abstract

Background: Platelet indices offer insights into platelet morphology and production, in addition to platelet count. In cancer patients, it is uncertain whether these indicators indicate tumor-specific traits or hematopoietic stress generated by chemotherapy. Aim: To evaluate platelet indices in patients receiving chemotherapy and ascertain whether they differ among cancer types or indicate treatment-related alterations. Methods: This comparative cross-sectional study included cancer patients undergoing chemotherapy and healthy controls. Platelet indicators evaluated were platelet count (PLT), mean platelet volume (MPV), mean platelet component (MPC), immature platelet fraction (IPF), platelet distribution width (PDW and PDWsd), plateletcrit (PCT), platelet large cell ratio (PLCR), and platelet large cell count (PLCC). Cancer diagnoses were grouped into 13 categories. Relationships between platelet parameters and treatment cycles were assessed using nonparametric methods, specifically the Mann–Whitney U and Kruskal–Wallis tests. Results: Marked disparities were observed between chemotherapy patients and controls, including lower MPV (p < 0.001) and PDW (p = 0.010), and elevated IPF (p = 0.039) and MPC (p = 0.047). PCT and PLCC exhibited significant differences (p < 0.05). No platelet indices showed significant variation among cancer types (all p > 0.05), while PLCR (p = 0.097) and PLCC (p = 0.087) demonstrated borderline trends. The IPF rose with each treatment cycle, signifying greater platelet turnover. Conclusion: Chemotherapy alters platelet indices, which do not vary across cancer types. The data indicate that platelet indices represent chemotherapy-induced hematopoietic stress rather than tumor-specific biology, with IPF potentially serving as a marker for treatment-related platelet dynamics.