Clinicopathologic characteristics of prefibrotic-early primary myelofibrosis in Chinese patients.

The clinicopathologic features of patients with prefibrotic-early primary myelofibrosis (PEPMF) are still uncertain, and the characteristics of PEPMF in Asian patients are rarely reported. This study analyzed the clinicopathologic characteristics of 42 Chinese patients with PMF newly diagnosed according to the 2008 World Health Organization criteria. Some clinical and laboratory features of the patients differed significantly from those of the predominantly white patients in Western countries. Chinese patients with PEPMF were more often male (1.28:1) and younger, less likely to have higher median hemoglobin concentrations (126 g/L), less frequently had palpable spleens (35.7%), and had longer median times between prefibrotic-early and classical PEPMF (64 months). On bone marrow trephine sections, Chinese patients were more likely to have increased granulopoiesis (78.6%) and less frequently had balloon-like megakaryocytes (61.9%), giant and staghorn megakaryocytes (35.7%), or megakaryocytes with hyperchromatic and dysplastic nuclei (40.4%). In conclusion, some clinicopathologic characteristics of PEPMF in Chinese patients in China differ substantially from those seen in predominantly white patients in Western countries, and more clinicopathologic studies involving different ethnic populations and geographic regions of the world should help unfold the characteristics of this disease.