title: Granulocytic sarcoma of the small intestine with CBFbeta/MYH11 fusion gene: report of an aleukaemic case and review of the literature.
abstract: Granulocytic sarcomas (GS) are rare extramedullary tumours composed of immature myeloid cells. Inversion of chromosome 16 [inv(16)] is a cytogenetic marker for M4Eo subtype of acute myeloid leukaemia (AML). The possibility of an association between the development of granulocytic sarcoma of the small intestine (GSSI) and the M4Eo subtype of AML was suggested in nine previous case reports. Here we report an aleukaemic case of GSSI with inv(16) and its molecular equivalent, the CBFbeta/MYH11 fusion gene, detected by reverse transcriptase-polymerase chain reaction (RT-PCR), that after treatment with conventional AML chemotherapy followed by autologous bone marrow transplantation, achieved complete haematological and molecular remission on bone marrow examination. After chemotherapy, a thickened ileum wall positive for CBFbeta/MYH11 on tumour mass samples was still observed on computed tomography (CT) studies, raising the question of residual GS representing a reservoir of malignant cells. This case demonstrates the critical need of multidisciplinary diagnosis and follow-up of this entity combining immunopathologic, cytogenetic and molecular studies, reinforcing the potentiality of risk-adapted therapy strategies, as it is increasingly claimed for patients with overt AML.
authors.affiliation: Bone Marrow Transplantation Center (CEMO), Instituto Nacional de Câncer (INCa), Praça da Cruz Vermelha 23, 7 Andar, 20230-130, Rio de Janeiro, RJ, Brazil.
authors.forename: Sandra G
authors.initials: SG
authors.lastname: Xavier
authors.forename: Evandro M
authors.initials: EM
authors.lastname: Fagundes
authors.forename: Rocío
authors.initials: R
authors.lastname: Hassan
authors.forename: Carlos
authors.initials: C
authors.lastname: Bacchi
authors.forename: Mônika
authors.initials: M
authors.lastname: Conchon
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Tabak
authors.forename: Nelson
authors.initials: N
authors.lastname: Spector
authors.forename: Ilana R
authors.initials: IR
authors.lastname: Zalcberg
mesh_terms: D000328:Adult; D006801:Humans; D007082:Ileum / Q000000981:diagnostic imaging; D007414:Intestinal Neoplasms / Q000235:genetics*; D007938:Leukemia / Q000150:complications; D008297:Male; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D023981:Sarcoma, Myeloid / Q000235:genetics*; D014057:Tomography, X-Ray Computed
chemical_list: C095514:CBFbeta-MYH11 fusion protein; D015514:Oncogene Proteins, Fusion