title: Thyrotoxicosis after denileukin diftitox therapy in patients with mycosis fungoides.
abstract: BACKGROUND
  Denileukin diftitox is a recombinant novel fusion protein of diphtheria toxin and the ligand-binding domain of human IL-2. Denileukin diftitox binds to the high-affinity IL-2 receptor on the cell surface, and it is internalized by endocytosis and enzymatically cleaved. The cytotoxic A-fragment of the toxin inhibits protein synthesis and causes cell death.
  
  
  OBJECTIVE
  The objective of this study was to recognize thyrotoxicosis in association with denileukin diftitox therapy.
  
  
  METHODS
  This study was a retrospective case series.
  
  
  METHODS
  The setting of this study was a comprehensive cancer center.
  
  
  METHODS
  Eight mycosis fungoides patients who were receiving 9 or 18 microg/kg.d iv denileukin diftitox for 5 d every 3 wk were identified with thyrotoxicosis.
  
  
  METHODS
  Thyroid testing was performed. Hypothyroidism after thyrotoxicosis was treated.
  
  
  RESULTS
  In eight mycosis fungoides patients who developed transient thyrotoxicosis during therapy, thyroid function tests were normal before onset of therapy. Clinical thyrotoxicosis developed within days of the first cycle of denileukin diftitox therapy in four patients and after the second cycle in the other four patients. Symptoms included tremors, nervousness, tachycardia, diarrhea, and weight loss. After cessation of denileukin diftitox, thyrotoxicosis resolved in all patients; two became euthyroid, and five became hypothyroid, requiring levothyroxine therapy. One patient was lost to follow-up.
  
  
  CONCLUSIONS
  Monitoring thyroid function before and during treatment with denileukin diftitox is recommended. Symptomatic thyrotoxicosis may be missed due to other acute reactions to the drug, and subsequent hypothyroidism may develop.
authors.affiliation: Department of Dermatology, University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Box 434, Houston, Texas 77030, USA.
authors.forename: Farah
authors.initials: F
authors.lastname: Ghori
authors.forename: Kristel D
authors.initials: KD
authors.lastname: Polder
authors.forename: Lauren C
authors.initials: LC
authors.lastname: Pinter-Brown
authors.forename: Ana O
authors.initials: AO
authors.lastname: Hoff
authors.forename: Robert F
authors.initials: RF
authors.lastname: Gagel
authors.forename: Steven I
authors.initials: SI
authors.lastname: Sherman
authors.forename: Madeleine
authors.initials: M
authors.lastname: Duvic
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects*; D004167:Diphtheria Toxin / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007376:Interleukin-2 / Q000009:adverse effects*; D007453:Iodide Peroxidase / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009182:Mycosis Fungoides / Q000188:drug therapy*; D011993:Recombinant Fusion Proteins / Q000009:adverse effects; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000188:drug therapy*; D013971:Thyrotoxicosis / Q000139:chemically induced*
chemical_list: D000970:Antineoplastic Agents; D004167:Diphtheria Toxin; D007376:Interleukin-2; D011993:Recombinant Fusion Proteins; C078456:denileukin diftitox; D007453:Iodide Peroxidase