Histiocytic sarcoma in patient with previously acute lymphoblastic leukemia. Case report

Abstract

Histiocytic sarcoma (HS) is a rare malignant neoplasm, with morphological and immunophenotypic characteristics similar to mature histiocytes, representing less than 1% of all hematological malignancies. HS can be associated with lymphomas, myelodysplasia, and some leukemias. Its clinical presentation varies from being localized to presenting systemic compromise. We present the clinical case of an 11-year-old boy with a 6-year OLD history of Acute Lymphoblastic Leukemia B, in complete continuous remission (CCR).  Two years after finishing his treatment, the patient presents symptoms of abdominal pain and vomiting, intermittent fever. Abomino-pelvic CT with expansive mass at the mesenteric level. With an anatomopathological diagnosis by biopsy of histiocytic sarcoma, he performed 2 cycles of preoperative chemotherapy, followed by a right hemicolectomy with complete resection. Due to compromised microscopic margins and infiltrated lymph nodes, it was decided to continue chemotherapy, completing two more cycles. Seven months after the diagnosis, 2 metabolically active retroperitoneal lymphadenopathies were confirmed by PET-CT and they were completely resected. With PET-CT control 9 months after the last surgery, there was no evidence of hyper-uptake lymphadenopathy. He currently remains in CCR 2 years after diagnosis.