{
  "abstract": "T-cell large granular lymphocyte leukaemia (T-LGLL) is a chronic lymphoproliferative disorder often associated with pure red cell aplasia (PRCA). We report a unique case of a woman in her 50s presenting with PRCA secondary to T-LGLL, in which targeted next-generation sequencing identified a somatic STAT3 P715L mutation. This variant, previously described only in germline mutation in STAT3 gain-of-function syndrome, has not been reported as a somatic mutation in T-LGLL. Immunohistochemical analysis revealed constitutive STAT3 (signal transducer and activator of transcription 3) activation in clonal CD8+ T cells, suggesting a pathogenic role for the P715L mutation. The patient responded to ciclosporin therapy with gradual haematological improvement and became transfusion-independent within 6 months. This case highlights the importance of molecular profiling in T-LGLL presentations and expands the known mutational spectrum of STAT3. It also raises the possibility that non-SH2 (Src homology 2) domain STAT3 mutations may contribute to disease pathogenesis and influence treatment response in T-LGLL.",
  "authors": [
    {
      "affiliations": [
        "Department of Hematology, Kyoto University Graduate School of Medicine Faculty of Medicine, Kyoto, Japan"
      ],
      "name": "Yusuke Okamoto"
    },
    {
      "affiliations": [
        "Department of Hematology, Kyoto University Graduate School of Medicine Faculty of Medicine, Kyoto, Japan"
      ],
      "name": "Kenichi Ishiyama"
    },
    {
      "affiliations": [
        "Department of Hematology, Kyoto University Graduate School of Medicine Faculty of Medicine, Kyoto, Japan"
      ],
      "name": "Kazuhisa Chonabayashi"
    },
    {
      "affiliations": [
        "Department of Hematology, Kyoto University Graduate School of Medicine Faculty of Medicine, Kyoto, Japan"
      ],
      "name": "Junya Kanda"
    },
    {
      "affiliations": [
        "Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine Faculty of Medicine, Kyoto, Japan"
      ],
      "name": "Munenori Kawai"
    },
    {
      "affiliations": [
        "Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine Faculty of Medicine, Kyoto, Japan"
      ],
      "name": "Akihisa Fukuda"
    },
    {
      "affiliations": [
        "Department of Pathology and Tumor Biology, Kyoto University, Kyoto, Japan",
        "Division of Hematopoietic Disease Control, The University of Tokyo, Tokyo, Japan"
      ],
      "name": "Yasuhito Nannya"
    },
    {
      "affiliations": [
        "Department of Pathology and Tumor Biology, Kyoto University, Kyoto, Japan",
        "Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Kyoto, Japan"
      ],
      "name": "Seishi Ogawa"
    },
    {
      "affiliations": [
        "Department of Hematology, Kyoto University Graduate School of Medicine Faculty of Medicine, Kyoto, Japan"
      ],
      "name": "Kouhei Yamashita"
    },
    {
      "affiliations": [
        "Department of Hematology, Kyoto University Graduate School of Medicine Faculty of Medicine, Kyoto, Japan"
      ],
      "name": "Akifumi Takaori"
    }
  ],
  "title": "T-cell large granular lymphocyte leukaemia with pure red cell aplasia harbouring a somatic STAT3 P715L mutation",
  "uid": "86b87b89-a2ca-51e0-98f0-8ee518ab6f99"
}