title: Comparison of outcome of POSSUM, p-POSSUM, and cr-POSSUM scoring after elective resection of the sigmoid colon for carcinoma or complicated diverticular disease.
abstract: OBJECTIVE
  To compare POSSUM, p-POSSUM, and cr-POSSUM-predicted mortalities with the observed postoperative mortality in patients undergoing elective sigmoid colectomy for diverticular disease (n=121) or carcinoma (n=120).
  
  
  METHODS
  The physiologic and operative severity score for the enumeration of mortality and morbidity (POSSUM) was used to identify patient- or disease-related risk factors and to calculate expected mortalities.
  
  
  RESULTS
  Patients with carcinoma had significantly higher POSSUM scores, but the observed mortality (1.7%) was lower than that in the diverticular disease group (3.3%). In the carcinoma group, mortality was over-predicted by all the POSSUM systems. In diverticular disease, POSSUM over-predicted mortality while p-POSSUM and cr-POSSUM under-predicted mortality. In the whole group, POSSUM over-predicted mortality. P-POSSUM and cr-POSSUM predicted mortality accurately: observed:expected (O:E) ratio 0.83. Replacing the score for malignancy with a minimum score of 1 gave overall O:E ratios of 0.37 (POSSUM), 1.04 (p-POSSUM), and 0.93 (cr-POSSUM).
  
  
  CONCLUSIONS
  In a group of patients who underwent elective resection of the sigmoid colon for carcinoma or diverticular disease, postoperative mortality was predicted accurately by p-Possum and cr-POSSUM, especially when used without a score for malignancy. None of the POSSUM scores were predictive of disease-specific mortality.
authors.affiliation: Department of Surgery, Zaans Medical Centre, Zaandam, The Netherlands. j.oomen4@chello.nl
authors.forename: Joannes L T
authors.initials: JL
authors.lastname: Oomen
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Cuesta
authors.forename: Alexander F
authors.initials: AF
authors.lastname: Engel
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000401:mortality* / Q000601:surgery; D012809:Colon, Sigmoid / Q000601:surgery*; D003107:Colorectal Surgery / Q000401:mortality*; D043963:Diverticulosis, Colonic / Q000145:classification / Q000401:mortality* / Q000601:surgery; D017558:Elective Surgical Procedures / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods; D012811:Sigmoid Neoplasms / Q000401:mortality* / Q000601:surgery; D016896:Treatment Outcome