RESUMEN
INTRODUCTION: Mastocytosis is a clonal haematological disease characterized by uncontrolled proliferation and the activation of mast cells. The value of FDG-PET/CT (FDG-PET) in mastocytosis has yet to be determined. METHODS: We retrospectively identified patients with an established diagnosis of systemic mastocytosis (SM), according to the WHO criteria, who underwent PET using the French Reference Centre for Mastocytosis database. Semi-quantitative and visual analysis of FDG-PET was performed and compared to the clinico-biological data. RESULTS: Our cohort included 19 adult patients, median age 65 years [range 58-74], including three with smouldering SM (SSM), three with aggressive SM (ASM), 10 with an associated clonal haematological non-mast-cell lineage disease (SM-AHNMD), and three with mast cell sarcoma (MCS). FDG-PET was performed at the time of the SM diagnosis (15/19), to evaluate lymph node (LN) activity (3/19) or the efficacy of therapy (1/19). FDG uptake was observed in the bone marrow (BM) (9/19, 47%), LN (6/19, 32%), spleen (12/19, 63%), or liver (1/19, 5%). No significant FDG uptake was observed in the SSM and ASM patients. A pathological FDG uptake was observed in the BM of 6/10 patients with SM-AHNMD, appearing as diffuse and homogeneous, and in the LN of 5/10 patients. All 3 MCS patients showed intense and multifocal BM pathological uptake, mimicking metastasis. No correlation was found between the FDG-PET findings and serum tryptase levels, BM mast cell infiltration percentage, and CD30 and CD2 expression by mast cells. CONCLUSIONS: FDG uptake does not appear to be a sensitive marker of mast cell activation or proliferation because no significant FDG uptake was observed in most common forms of mastocytosis (notably purely aggressive SM). However, pathological FDG uptake was observed in the SM-AHNMD and in MCS cases, suggesting a role of FDG-PET in their early identification and as a tool of therapeutic assessment in this subgroup of patients.
Asunto(s)
Mastocitosis Sistémica/diagnóstico por imagen , Imagen Multimodal , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Anciano , Femenino , Fluorodesoxiglucosa F18 , Francia , Humanos , Masculino , Persona de Mediana Edad , RadiofármacosAsunto(s)
Deficiencia GATA2/diagnóstico , Factor de Transcripción GATA2/genética , Micosis Fungoide/diagnóstico , Neoplasias Cutáneas/diagnóstico , Piel/patología , Adulto , Análisis Mutacional de ADN , Deficiencia GATA2/complicaciones , Deficiencia GATA2/genética , Deficiencia GATA2/patología , Humanos , Masculino , Micosis Fungoide/complicaciones , Micosis Fungoide/genética , Micosis Fungoide/patología , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patologíaRESUMEN
BACKGROUND: This study compared the induction regimens doxorubicin, cyclophosphamide and etoposide (ACE) with doxorubicin, cyclophosphamide, vincristine, bleomycin and prednisone (ACVBP) before high-dose therapy (HDT) followed by autologous stem-cell transplantation (ASCT) for patients with poor-risk diffuse large B-cell lymphoma (DLBCL). A second randomisation compared rituximab with observation post-ASCT. MATERIALS AND METHODS: Four hundred and seventy-six patients <60 years old with newly diagnosed CD20+ DLBCL were randomised to induction with ACE or ACVBP. Three hundred and thirty responders received HDT followed by ASCT. After ASCT, 269 patients were re-randomised to receive either maintenance rituximab or observation alone. Randomisation was stratified by the quality of response to ASCT. The primary end point of this study was event-free survival (EFS). RESULTS: At a median of 4 years' follow-up from the second randomisation, there was a trend (P = 0.1) towards increased EFS for patients who received rituximab compared with observation. CONCLUSION: The type of induction therapy (ACVBP or ACE) did not significantly affect overall survival at a median 51 months' follow-up.