title: Hypothalamic pituitary dysfunction amongst nasopharyngeal cancer survivors.
abstract: OBJECTIVE
  Radiation fields for nasopharyngeal cancer (NPC) include the base of skull, which places the hypothalamus and pituitary at risk of damage. We aimed to establish the prevalence, pattern and severity of hypothalamic pituitary (HP) dysfunction amongst NPC survivors.
  
  
  METHODS
  We studied 50 patients (31 males) with mean age 57 ± 12.2 years who had treatment for NPC between 3 and 21 years (median 8 years) without pre-existing HP disorder from other causes. All patients had a baseline cortisol, fT4, TSH, LH, FSH, oestradiol/testosterone, prolactin and renal function. All patients underwent dynamic testing with insulin tolerance test to assess the somatotroph and corticotroph axes. Baseline blood measurements were used to assess thyrotroph, gonadotroph and lactotroph function.
  
  
  RESULTS
  Hypopituitarism was present in 82% of patients, 30% single axis, 28% two axes, 18% three axes and 6% four axes deficiencies. Somatotroph deficiency was most common (78%) while corticotroph, gonadotroph and thyrotroph deficiencies were noted in 40% (4 complete/16 partial), 22 and 4% of the patients respectively. Hyperprolactinaemia was present in 30% of patients. The development of HP dysfunction was significantly associated with the time elapsed from irradiation, OR 2.5 (1.2, 5.3), p = 0.02, for every 2 years post treatment. The use of concurrent chemo-irradiation (CCRT) compared to those who had radiotherapy alone was also significantly associated with HP dysfunction, OR 14.5 (2.4, 87.7), p < 0.01.
  
  
  CONCLUSIONS
  Despite low awareness and detection rates, HP dysfunction post-NPC irradiation is common. Use of CCRT may augment time related pituitary damage. As these endocrinopathies result in significant morbidity and mortality we recommend periodic assessment of pituitary function amongst NPC survivors.
authors.affiliation: Endocrine Unit, Department of Medicine, University Malaya Medical Centre, Kuala Lumpur, Malaysia, jeyakantha_r@hotmail.com.
authors.forename: J
authors.initials: J
authors.lastname: Ratnasingam
authors.forename: N
authors.initials: N
authors.lastname: Karim
authors.forename: S S
authors.initials: SS
authors.lastname: Paramasivam
authors.forename: L
authors.initials: L
authors.lastname: Ibrahim
authors.forename: L L
authors.initials: LL
authors.lastname: Lim
authors.forename: A T B
authors.initials: AT
authors.lastname: Tan
authors.forename: S R
authors.initials: SR
authors.lastname: Vethakkan
authors.forename: A
authors.initials: A
authors.lastname: Jalaludin
authors.forename: S P
authors.initials: SP
authors.lastname: Chan
mesh_terms: D000368:Aged; D059248:Chemoradiotherapy; D003430:Cross-Sectional Studies; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D019382:Human Growth Hormone / Q000172:deficiency*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D006966:Hyperprolactinemia / Q000097:blood / Q000453:epidemiology*; D007006:Hypogonadism / Q000097:blood / Q000453:epidemiology; D007018:Hypopituitarism / Q000097:blood / Q000453:epidemiology*; D007030:Hypothalamo-Hypophyseal System; D007037:Hypothyroidism / Q000097:blood / Q000453:epidemiology; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000628:therapy*; D058958:Organs at Risk; D011388:Prolactin / Q000097:blood; D011878:Radiotherapy; D017741:Survivors; D013739:Testosterone / Q000097:blood; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood
chemical_list: D019382:Human Growth Hormone; D013739:Testosterone; D004958:Estradiol; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin; D013974:Thyroxine; D006854:Hydrocortisone