title: Anorectal melanoma--an incurable disease?
abstract: OBJECTIVE
  This study was designed to describe recurrence and survival rates after operative treatment for anorectal melanoma and to identify predictive factors for recurrence.
  
  
  METHODS
  Records of 50 patients with anorectal melanoma from 1939 to 1993 were reviewed.
  
  
  RESULTS
  Overall five-year survival and disease-free survival were 22 and 16 percent, respectively. At the time of diagnosis, 26 percent of patients had metastatic disease, and all died within 12 (mean, 6.3) months. Five-year survival and recurrence rates were identical after either abdominoperineal resection (APR) or wide local excision, both with curative intent. Gender, size of tumor, presence of melanin, positive perirectal lymph nodes, or treatment were not predictive of recurrence. Anorectal melanoma was found incidentally after hemorrhoidectomy or polypectomy in five patients. Three other patients underwent an excisional biopsy of a lesion measuring less than 2 cm. Of these eight patients, five underwent APR and three underwent wide local excision with no microscopic residual tumor at pathology. All developed regional or systemic recurrence at a mean of 21 (range, 4-88) months, and all died of their disease at a mean of 29 (range, 5-98) months.
  
  
  CONCLUSIONS
  Prognosis for anorectal melanoma is poor, irrespective of surgical treatment performed. No predictive factors for recurrence were identified in this series. Wide local excision with a negative margin of a least 1 cm is suggested as the treatment of choice. APR should be reserved for tumor not amenable to local excision or for palliative treatment of large obstructive lesion until effective adjuvant therapies are available.
authors.affiliation: Division of Colon and Rectal Surgery, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA.
authors.forename: C
authors.initials: C
authors.lastname: Thibault
authors.forename: P
authors.initials: P
authors.lastname: Sagar
authors.forename: S
authors.initials: S
authors.lastname: Nivatvongs
authors.forename: D M
authors.initials: DM
authors.lastname: Ilstrup
authors.forename: B G
authors.initials: BG
authors.lastname: Wolff
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001005:Anus Neoplasms / Q000401:mortality / Q000601:surgery*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008545:Melanoma / Q000401:mortality / Q000556:secondary / Q000601:surgery*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D011237:Predictive Value of Tests; D011379:Prognosis; D012004:Rectal Neoplasms / Q000401:mortality / Q000601:surgery*; D012189:Retrospective Studies; D012307:Risk Factors; D018709:Statistics, Nonparametric; D015996:Survival Rate