title: Risk factors for postoperative complications in oral cancer and their prognostic implications.
abstract: BACKGROUND
  The surgical treatment of head and neck cancer can be limited by the risk of postoperative complications. Early identification of risk factors based on clinical characteristics may assist therapeutic planning.
  
  
  OBJECTIVE
  To identify risk factors for these complications and to evaluate their prognostic significance.
  
  
  METHODS
  The medical records of 110 patients with oral squamous cell carcinoma admitted from January 1, 1990, to December 31, 1994, who underwent radical surgery were reviewed. Data collected included demographic information, comorbidities, extended clinical severity stage, treatment, complications, and survival. The chi(2) test was used to verify the association between the variables. Survival analysis was performed with the Kaplan-Meier method. Logistic and Cox proportional hazards regression were used to build models with independent predictive factors for the risk of complications and death, respectively.
  
  
  RESULTS
  The overall complication rate was 50%. Dehiscence and infection rates were 20.9% and 22.7%, respectively. The death rate was 3.6%. Forty-seven patients (42.7%) were electively referred to the intensive care unit (ICU). The occurrence of postoperative complications was associated with extended clinical severity stage (P =.02), type of surgery (P =.03), ICU (P =.03), type of reconstruction (P =.02), Functional Severity Index (P =.03), neck dissection (P =.002), and APACHE II (Acute Physiology and Chronic Health Evaluation II) (P =.008). The number of complications was significantly correlated with the length of hospital stay (r = 0.24, P =.01) and with the Functional Severity Index (r = 0.19, P =.04). Five-year overall survival was affected by the type of complications (none, 41.7%; local, 34.1%; and local plus systemic, 0% [P<.001]), ICU (no, 46.3%; yes, 20.7% [P =.001]), and extended clinical severity stage (stage 1, 75.6%; stage 2, 50%; stage 3, 28.6%; and stage 4, 10.2% [P<.001]). In a multivariate analysis bilateral neck dissection (relative risk = 3.57, P =.01) and an APACHE II score greater than 10 (relative risk = 3.86, P =.02) were independent risk factors for complications. The predictive prognostic model consisted of the following: staying in the ICU (hazard ratio = 1.83), local plus systemic complications (hazard ratio = 6.27), and extended clinical severity stage (stage 3, hazard ratio = 3.57; stage 4, hazard ratio = 6.34).
  
  
  CONCLUSIONS
  Bilateral neck dissection and the APACHE II score were identified as risk factors for postoperative complications in oral cancer, which also increase the length of hospital stay. The occurrence of systemic complications, advanced extended clinical severity stage, and staying in an ICU adversely affect the prognosis. Therefore, the prompt recognition of the adverse risk factors for postoperative complications may guide proactive interventions that may improve survival and achieve cost-effectiveness.
authors.affiliation: Department of Head and Neck Surgery, Centro de Tratamento e Pesquisa Hospital do Câncer A. C. Camargo, R. Professor Antônio Pudente, 211CEP 01509-010 São Paulo-SP, Brazil.
authors.forename: G M
authors.initials: GM
authors.lastname: de Melo
authors.forename: K C
authors.initials: KC
authors.lastname: Ribeiro
authors.forename: L P
authors.initials: LP
authors.lastname: Kowalski
authors.forename: D
authors.initials: D
authors.lastname: Deheinzelin
mesh_terms: D018806:APACHE; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D009060:Mouth Floor / Q000473:pathology / Q000601:surgery; D009062:Mouth Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D037981:Neck Dissection; D009367:Neoplasm Staging; D011183:Postoperative Complications / Q000209:etiology* / Q000401:mortality; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors; D015996:Survival Rate; D014062:Tongue Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*