Objective: Klippel–Trenaunay syndrome (KTS) has been associated with capillary, venous, lymphatic and soft tissue malformations, whether it predisposes to malignancy is not clear. We report a case of chronic myeloid leukemia (CML) with KTS. We report this case because of its rarity and need for long term follow-up.
Case report: A 14-year-old boy presented with a painless mass on his left groin which was extending to his knee. Physical examination revealed splenomegaly, limb length discrepancy, left lower extremity hypertrophy and capillary hemangiomas over the posterolateral skin of the left thigh. KTS was suspected and confirmed with heterozygous mutation (c1634A>C/p.Glu545Ala) at the PIK3CA gene. The patient consulted to the hematology due to hemorrhage complication of the surgery. Complete blood counts showed a hemoglobin level of 7.3g/dL, white blood cell as 164×109/L, neutrophil 76.4×109/L and thrombocytes 104×109/L). The differential was metamyelocytes 20%, bands 4%, neutrophils 70%, eosinophils 4%, lymphocytes 2%, normoblast 4%, except circulating blasts. Bone marrow aspiration showed normocellular myeloid/erythroid ratio of 23:1, granulopoiesis with left shift, increased megakaryocytes seen with normal maturation and blasts were lower than 5%. RT-PCR from peripheral blood was positive for the BCR-ABL p210 transcript. Conventional karyotyping revealed a typical 46 XY, t(9,22)(q34;q11.2) without any additional cytogenetic abnormalities in all (20/20, 100%). Chronic phase CML (CML-CP) was diagnosed, and imatinib was initiated with a 300mg/m2 dose daily.
Results: To our knowledge there has been no description of an association between KTS syndrome and CML in the literature. We report this case because of its rarity.
Conclusion: Klippel–Trenaunay syndrome is a rare congenital malformation involving blood and lymph vessels and abnormal growth of soft and bone tissue. The exact cause of KTS is not clear, several genes and pathways have been identified in its pathogenesis. Remarkably, PIK3CA gene mutations have been detected in some cases of KTS. PIK3CA encodes for a subunit of the phosphoinositide 3-kinase enzyme, which is involved in cell proliferation and migration. The angiogenic gene VG5Q has also been implicated in KTS. We report the case of a 14 year-old boy with diagnosed KTS, who presented with a bleeding from the surgical region that was found to be a chronic myeloid leukemia. To our knowledge there has been no description of an association between KTS syndrome and CML. In the literature, there are cases where KTS is associated with Wilms tumor, neurofibromatosis and osteoblastoma, but no hematologic malignancy has been so far.
