Usefulness of spleen volume measured by computed tomography for predicting clinical outcome in primary myelofibrosis

Abstract

Although splenomegaly is major characteristic of primary myelofibrosis (PMF), splenomegaly has been devalued due to a less reliable method based on physical examination (PEx). We evaluated whether spleen volume (SV) on CT would accurately predict clinical outcomes in PMF. A total of 188 patients were enrolled. SV was quantitated by the automatic volume software. In ROC curve, the SV predicted prognosis more accurately than spleen length by PEx (p < 0.001). The ideal cut-off value was 378.1 cm3 for SV, which was divided into high- and low-volume status. Patients with low SV status had superior leukemia-free survival and overall survival compared to high SV status (p < 0.001, p < 0.001) In the Cox analysis, old age ≥65 years (p = 0.004, p = 0.001), low Hemoglobin <10.0 g/dL (p = 0.023, p = 0.021), high WBC counts ≥25 × 109/L (p = 0.003, p = 0.006), peripheral blasts ≥1 % (p = 0.029, p = 0.020), unfavorable cytogenetic abnormalities (p = 0.025, p = 0.028), and high SV status (p = 0.004, p = 0.003) were independently associated with survivals. SV measured by CT was important for predicting survival in patients with PMF.