title: Prognostic factors and survival rates for parotid duct carcinoma patients.
abstract: OBJECTIVE
  To investigate the survival rates of patients diagnosed with parotid duct carcinoma (PDC) and analyze the associated risk factors.
  
  
  METHODS
  This study included 38 patients with PDC and the following information was collected for each patient: gender, age, tumor size, TNM classification, neck node metastasis, House-Brackmann grade, neural invasion, use of postoperative radiation therapy and survival data. The Kaplan-Meier method and the Cox model were used to determine prognostic factors for disease-specific survival (DSS) and recurrence-free survival (RFS) rates.
  
  
  RESULTS
  Of the 38 patients, 36 (94.7%) were male. Mean age at initial diagnosis was 59.9 years (range: 43-79). A total of 32 (84.2%) patients had T3/T4 tumors, and 29 (76.3%) patients had a preoperative House-Brackmann grade of I/II. A correlation analysis showed that tumor stage was significantly associated with House-Brackmann grade (Spearman r = 0.521, p = 0.001). The 5-year DSS and RFS rates were 45% and 30%, respectively. Using Cox-regression analysis, node metastasis and the preoperative House-Brackmann grade were the independent predictors of both RFS and DSS. Postoperative radiation could decrease disease recurrence, but did not improve disease-specific survival.
  
  
  CONCLUSIONS
  Parotid duct carcinoma is an aggressive tumor. Node status and preoperative House-Brackmann grade are key prognostic factors.
authors.affiliation: Department of Pediatric Dentistry, School of Stomatology, China Medical University, Shenyang, PR China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Shi
authors.affiliation: Department of Oral Maxillofacial Surgery, School of Stomatology, China Medical University, No.117, Nanjing North Street, Heping District, Shenyang, Liaoning 110002, PR China.
authors.forename: Qigen
authors.initials: Q
authors.lastname: Fang
authors.affiliation: Department of Oral Maxillofacial Surgery, School of Stomatology, China Medical University, No.117, Nanjing North Street, Heping District, Shenyang, Liaoning 110002, PR China.
authors.forename: Fayu
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Oral Pathology, School of Stomatology, China Medical University, Shenyang, PR China.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhong
authors.affiliation: Department of Oral Maxillofacial Surgery, School of Stomatology, China Medical University, No.117, Nanjing North Street, Heping District, Shenyang, Liaoning 110002, PR China. Electronic address: changfusun@hotmail.com.
authors.forename: Changfu
authors.initials: C
authors.lastname: Sun
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002277:Carcinoma / Q000453:epidemiology* / Q000401:mortality / Q000556:secondary; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology / Q000401:mortality; D009367:Neoplasm Staging; D010307:Parotid Neoplasms / Q000453:epidemiology* / Q000401:mortality; D011379:Prognosis; D018714:Radiotherapy, Adjuvant / Q000706:statistics & numerical data; D018987:Salivary Ducts / Q000473:pathology*; D015996:Survival Rate
keywords: House–Brackmann grade; Parotid duct carcinoma; Prognosis; Salivary duct carcinoma; Survival analysis