title: Failure patterns and factors affecting prognosis of salivary gland carcinoma: retrospective study.
abstract: OBJECTIVE
  To investigate the failure patterns and the prognostic factors following postoperative radiotherapy for salivary gland carcinoma.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  University teaching hospital, Hong Kong.
  
  
  METHODS
  Fifty patients who had non-disseminated salivary gland carcinoma and who received primary treatment from 1984 through 1993.
  
  
  METHODS
  Demographic data, cancer T- and N-stages, histological type, site of origin, completeness of surgery, whether postoperative radiotherapy was given, and the clinical outcome.
  
  
  RESULTS
  Two (4%) patients had been treated with radiotherapy alone, six (12%) had undergone radical resection alone, and 42 (84%) had been radically treated by using both modalities. The 5-year overall survival and relapse-free survival rates were 78.4% and 63.1%, respectively. The free from local failure and free from distant metastasis rates at 5 years were 77.2% and 72.8%, respectively. The N-stage was a significant prognostic factor. The site of the primary tumour, T-stage, completeness of surgery, and use of postoperative radiotherapy were not significant independent prognosticators; however, among the T-stage tumours, the b-substage carcinomas had significantly fewer local failures (P=0.040) and better survival rates (P=0.038) than the a-substage carcinomas. There were seven (14%) locoregional failures without distant metastasis, seven (14%) cases of distant metastasis without locoregional failures, and four (8%) locoregional failures preceding distant metastasis; isolated regional relapse was rare (1/50; 2%). All regional failures (5/50; 10%) occurred ipsilateral to the primary lesion. There were no deaths due to lymphoepithelioma-like carcinoma or acinic cell carcinoma.
  
  
  CONCLUSIONS
  The N-stage is the main prognostic factor of overall survival, relapse- and metastasis-free recovery, and success of treatment for salivary gland carcinoma. Optimal locoregional treatment can help reduce distant metastasis, and the maximal use of postoperative radiotherapy may contribute to improved locoregional control. Elective ipsilateral neck radiotherapy is indicated for lymphoepithelioma-like carcinoma.
authors.affiliation: Department of Clinical Oncology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
authors.forename: P M
authors.initials: PM
authors.lastname: Teo
authors.forename: A T
authors.initials: AT
authors.lastname: Chan
authors.forename: W Y
authors.initials: WY
authors.lastname: Lee
authors.forename: S F
authors.initials: SF
authors.lastname: Leung
authors.forename: E S
authors.initials: ES
authors.lastname: Chan
authors.forename: C O
authors.initials: CO
authors.lastname: Mok
mesh_terms: D003528:Carcinoma, Adenoid Cystic / Q000401:mortality / Q000628:therapy; D018277:Carcinoma, Mucoepidermoid / Q000401:mortality / Q000628:therapy; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000628:therapy; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012468:Salivary Gland Neoplasms / Q000401:mortality* / Q000628:therapy; D015996:Survival Rate; D017211:Treatment Failure