title: Treatment of merkel cell carcinoma.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the treatment of Merkel cell carcinoma.
  
  
  METHODS
  We reviewed 85 cases of Merkel cell carcinoma. There were 68 males and 17 females. The majority of cases involved head and neck sites (48%), followed by the extremities (38%) and trunk (14%). Sixty-seven percent of the patients had stage I disease that was localized to the skin of origin at presentation. Twenty-five percent and 8% were stage II (nodal metastasis) and stage III (distant metastasis), respectively. Surgical intervention included local or wide local excision +/- nodal dissection (68%), radical resection +/- nodal dissection (22%), and amputation (4%). Five patients (6%) underwent biopsy only because of metastatic disease or unresectability at presentation. Fifty-one percent received adjuvant therapy consisting of external beam radiation therapy and/or combination chemotherapy.
  
  
  RESULTS
  With an average follow-up time of 39.5 months, 12% had persistent disease and 40% had recurrent disease. The median time to recurrence was 8 months with a mean of 10.6 months. Although the addition of adjuvant therapy did not affect survival, the recurrence rate was 32.5% for surgery +/- adjuvant radiation therapy +/- chemotherapy as compared with 52.7% for surgery-only patients. Although the 40.7% recurrence rate for patients receiving surgery and adjuvant radiation therapy was approximately the same as for patients receiving surgery and adjuvant chemotherapy (40%), the effect of systemic chemotherapy on recurrence is less clear as a result of the small number of patients who received such therapy. Although tumor size and site of presentation were not observed to be statistically significant in overall survival, significant differences were observed based on sex and tumor stage. For females, the median survival time was 96 months (mean, 94.5 months) compared with 63 months (mean, 76.8 months) for males. This difference was significant (P < 0.01). Patients presenting with low-stage (stage I) disease had a significant (P < 0.01) survival benefit when compared with high-stage individuals (stages II and III). The 5-year actuarial survival rates were 68% and 42%, respectively.
  
  
  CONCLUSIONS
  In this retrospective study, surgery remains the primary modality for Merkel cell carcinoma, and adjuvant radiation therapy +/- systemic chemotherapy reduces local recurrence. Female patients and those who present with early-stage disease appear to have a better prognosis.
authors.affiliation: Department of Radiation Oncology, University of Texas, Health Science Center at San Antonio/CTRC, San Antonio, Texas 78229, USA. tyeng@pol.net
authors.forename: Tony Y
authors.initials: TY
authors.lastname: Eng
authors.forename: Melisa G K
authors.initials: MG
authors.lastname: Boersma
authors.forename: Clifton D
authors.initials: CD
authors.lastname: Fuller
authors.forename: Sean X
authors.initials: SX
authors.lastname: Cavanaugh
authors.forename: Fabio
authors.initials: F
authors.lastname: Valenzuela
authors.forename: Terence S
authors.initials: TS
authors.lastname: Herman
mesh_terms: D000368:Aged; D015266:Carcinoma, Merkel Cell / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008297:Male; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D016019:Survival Analysis