摘要To the Editor:We report a 27-year-old woman with a 2-month history of irregular uterine bleeding between periods.Blistering on the head was noted in the patient at the age of 2 months,and she gradually developed red maculopapular lesions over her neck and back during puberty,which were itchy after exposure to physical friction.On admission,physical examination had revealed diffuse faint maculopapular rash mainly on the neck and back [Figure 1].Pelvic examination showed a smooth red lump (5 cm) on the cervix.No abnormality was detected in the complete blood count.Afterwards,the cervical lump was resected and confirmed to be the infiltration of mature mast cells (MCs) after careful pathological investigation.Additionally,a skin nodule biopsy also indicated mass aggregation of MCs,and a bone marrow (BM) biopsy showed a mass of round MCs with abundant cytoplasmic granules.The MCs accounted for about 22.5％ of all cells in the aspirate smears.Flow cytometry immunophenotypic analysis on BM suggested that an aberrant MC population had represented 10％ of the total analyzed cells,which was positive for CD117,CD33,and CDg,partially positive for CD2 and CD68,and negative for CD25.Genetic test through exome-wide sequencing for the receptor tyrosine kinase (KIT) gene had revealed K509I mutation.