title: Multifocal soft tissue Langerhans' cell histiocytosis treated with PET-CT based conformal radiotherapy.
abstract: BACKGROUND
  Langerhans' cell histiocytosis (LCH) is a proliferative disorder of Langerhans cells, which is seen extremely rarely in adults. Conventional imaging modalities, such as skeletal surveys and bone scans, were accepted to be standard methods for diagnosis; however, 18-fluorodeoxyglucose positron emission tomography (PET-CT) has been increasingly used.
  
  
  METHODS
  We report on a 33-year-old female patient with disseminated LCH treated with radiotherapy and systemic chemotherapy where PET-CT has been used for defining the extent of the disease, RT planning and assessment of treatment response during follow-up.
  
  
  RESULTS
  The patient was treated with 24 Gy 3-dimensional conformal radiotherapy (RT), given as 2 Gy a day, 5 days a week. The patient was also treated with systemic prednisolone 20 mg/m(2), concurrently. The chemotherapeutic regimen switched to cytosine-arabinoside with a dose of 100 mg/m(2) subcutaneously daily for 4 days, vincristine 1.5 mg/m(2) given on the 1st day and prednisolone 20 mg/m(2) for 4 cycles. After local RT with adjuvant chemotherapy, the patient was alive for 54 months and remained disease-free at last visit.
  
  
  CONCLUSIONS
  RT is a treatment choice in multi-system LCH as well as solitary lesions. Low-dose RT is adequate to control large masses of LCH including soft tissue and lymph nodes.
authors.affiliation: Department of Radiation Oncology, Baskent University Faculty of Medicine, Adana, Turkey. hcemonal@hotmail.com.|Adana Research and Treatment Centre, Department of Radiation Oncology, Baskent University Faculty of Medicine, 01120, Adana, Turkey. hcemonal@hotmail.com.
authors.forename: Cem
authors.initials: C
authors.lastname: Onal
authors.affiliation: Department of Radiation Oncology, Baskent University Faculty of Medicine, Adana, Turkey.
authors.forename: Ezgi
authors.initials: E
authors.lastname: Oymak
authors.affiliation: Department of Nuclear Medicine, Baskent University Faculty of Medicine, Ankara, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Reyhan
authors.affiliation: Department of Pathology, Baskent University Faculty of Medicine, Ankara, Turkey.
authors.forename: Tuba
authors.initials: T
authors.lastname: Canpolat
authors.affiliation: Division of Medical Oncology, Baskent University Faculty of Medicine, Ankara, Turkey.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Ozyilkan
mesh_terms: D000328:Adult; D005260:Female; D019788:Fluorodeoxyglucose F18; D006646:Histiocytosis, Langerhans-Cell / Q000175:diagnosis* / Q000188:drug therapy / Q000532:radiotherapy*; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D020266:Radiotherapy, Conformal; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Langerhans’ cell histiocytosis; Positron emission tomography; Radiotherapy