title: Unknown primary cancer presenting as an adrenal mass: frequency and implications for diagnostic evaluation of adrenal incidentalomas.
abstract: BACKGROUND
  Fine-needle aspiration biopsy to identify adrenal metastasis from an occult primary malignancy has been recommended as part of the evaluation of the patient who presents with an incidentally discovered adrenal mass. This recommendation was assessed by examining the frequency of adrenal involvement in patients with suspected unknown primary cancer.
  
  
  METHODS
  Data from 1715 patients referred for evaluation of suspected unknown primary cancer were retrospectively reviewed.
  
  
  RESULTS
  Of 1639 patients found to have cancer, the adrenal gland was identified as a site of involvement at presentation in 95 (5.8%). Involvement was limited to the adrenal gland in 4 patients (0.2%). All 4 patients had large (> or = 6 cm) adrenal tumors, 3 of 4 had bilateral involvement, and all had symptoms that otherwise mandated evaluation for an occult malignancy; none had a true adrenal incidentaloma.
  
  
  CONCLUSIONS
  Although cancer of an unknown primary site occasionally involves the adrenal gland, metastatic cancer presenting as a true adrenal incidentaloma is extremely rare. Therefore, in the absence of a history of prior malignancy or symptoms, physical examination findings, radiographic findings, or laboratory findings suggestive of an occult malignancy, we do not recommend fine-needle aspiration biopsy as part of the diagnostic evaluation of the patient who presents with a unilateral adrenal mass.
authors.affiliation: Department of Surgical Oncology, University of Texas, M. D. Anderson Cancer Center, Houston 77030, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Lee
authors.forename: D B
authors.initials: DB
authors.lastname: Evans
authors.forename: R C
authors.initials: RC
authors.lastname: Hickey
authors.forename: S I
authors.initials: SI
authors.lastname: Sherman
authors.forename: R F
authors.initials: RF
authors.lastname: Gagel
authors.forename: M C
authors.initials: MC
authors.lastname: Abbruzzese
authors.forename: J L
authors.initials: JL
authors.lastname: Abbruzzese
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000556:secondary*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009382:Neoplasms, Unknown Primary / Q000473:pathology*; D012189:Retrospective Studies