hematology and oncology
Cutaneous T cell Lymphomas (CTCL)
Diagnosis of Cutaneous T cell Lymphomas
Skin biopsy Peripheral blood smear and flow cytometry for circulating malignant T-cells (Sézary cells) For staging, lymph node biopsy and CT of chest, abdomen, and pelvis or FDG-PET (fluorodeoxyglucose-positron emission tomography) Diagnosis is based on skin biopsy, but histology may be equivocal early in the course because of insufficient quantities of lymphoma cells. The malignant cells are mature CD4+ T cells that may have lost common T-cell markers such as CD7. Characteristic Pautrier microabscesses are present in the epidermis on skin punch biopsies. In some cases, a leukemic phase called Sézary syndrome is characterized by the appearance of malignant T cells with serpentine nuclei in the peripheral blood. These can be detected on a routine Wright-stained smear or by flow cytometry. After diagnosis, stage is determined to guide therapy. The commonly used ISCL/EORTC (International Society of Cutaneous Lymphomas/European Organization of Research and Treatment of Cancer) staging system incorporates physical examination findings, histopathology results, and results of imaging tests Diagnosis references . 1.Olsen EA: Evaluation, diagnosis, and staging of cutaneous lymphoma.Dermatol Clin33(4):643–654, 2015. doi: 10.1016/j.det.2015.06.001 2.Willemze R, Cerroni L, Kempf W, et al: The 2018 update of the WHO-EORTC classification for primary cutaneous lymphomas.Blood133 (16):1703–1714, 2019. doi: 10.1182/blood-2018-11-881268 