title: Transrectal ultrasound appearance of radiation-induced prostatic sarcoma.
abstract: BACKGROUND
  Delayed development of prostatic sarcoma is a rare complication of prostatic pelvic irradiation. The transrectal ultrasound appearance of this lesion has not been previously described.
  
  
  METHODS
  Three cases of radiation-induced prostatic sarcoma are presented, with emphasis on the transrectal ultrasound findings.
  
  
  RESULTS
  An irregular, hypoechoic prostatic mass with an anechoic area consistent with the echogenicity of muscle and/or necrosis was found in all 3 patients. This appearance is distinctly dissimilar from prostatic adenocarcinoma.
  
  
  CONCLUSIONS
  The sonographic finding of an irregular, hypoechoic prostatic mass with an anechoic area should raise suspicion for prostatic sarcoma in patients with a history of pelvic irradiation who develop an abnormal prostate on rectal examination and/or worsening voiding symptoms despite a normal serum prostate-specific antigen level.
authors.affiliation: Section of Urology, Palo Alto Veterans Affairs Health Care System, California 94304, USA. mkt@icon.palo-alto.med.va.gov
authors.forename: M K
authors.initials: MK
authors.lastname: Terris
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017809:Fatal Outcome; D006801:Humans; D008297:Male; D008875:Middle Aged; D009381:Neoplasms, Radiation-Induced / Q000000981:diagnostic imaging*; D010388:Pelvis / Q000528:radiation effects; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging*; D012007:Rectum; D012509:Sarcoma / Q000000981:diagnostic imaging*; D014463:Ultrasonography / Q000379:methods