title: Postoperative recurrence and risk factors of colorectal cancer perforation.
abstract: OBJECTIVE
  The common causes of colorectal perforation are benign. However, perforated colorectal cancer confers a risk of recurrence in the long term because of the malignant nature of the disease. In addition, the recurrence rate can also increase because of dissemination of cancer cells, reduced extent of lymph node dissection to prioritize saving life, and other reasons.
  
  
  METHODS
  We evaluated the clinical features and postoperative recurrence in patients with perforated colorectal cancer who developed general peritonitis and underwent emergency surgery during a 7-year period between April 2007 and March 2014.
  
  
  RESULTS
  During the study period, 44 patients had colorectal cancer perforation. The cancer sites were the ascending colon in 6 patients, transverse colon in 1, descending colon in 4, sigmoid colon in 15, and rectum in 18. The disease stage was stage II in 18 patients, stage III in 15, and stage IV in 7. Among 22 patients who could be followed up, 8 had postoperative recurrence. The recurrence rates were 18.2% for stage II cancer and 54.5% for stage III. Postoperative recurrence was more likely to occur in the patients positive for lymph node metastasis, those with poorly differentiated adenocarcinoma, those with T4 cancer, and those who did not receive postoperative adjuvant chemotherapy.
  
  
  CONCLUSIONS
  The recurrence rate was higher in the patients with perforated colorectal cancer than in those who underwent surgery for common colorectal cancer. The prognosis can be expected to improve by performing standard surgical procedures, to the maximum extent possible, followed by postoperative adjuvant chemotherapy.
authors: Department of General Surgery, Saitama Medical University, 38 Morohongou, Moroyama, Irumagun, Saitama, 350-0495, Japan. hiroshia@saitama-med.ac.jp.
authors: Hiroshi
authors: http://orcid.org/0000-0002-5867-8899
authors: H
authors: Asano
authors: Department of General Surgery, Saitama Medical University, 38 Morohongou, Moroyama, Irumagun, Saitama, 350-0495, Japan.
authors: Kazuto
authors: K
authors: Kojima
authors: Department of General Surgery, Saitama Medical University, 38 Morohongou, Moroyama, Irumagun, Saitama, 350-0495, Japan.
authors: Naomi
authors: N
authors: Ogino
authors: Department of General Surgery, Saitama Medical University, 38 Morohongou, Moroyama, Irumagun, Saitama, 350-0495, Japan.
authors: Hiroyuki
authors: H
authors: Fukano
authors: Department of General Surgery, Saitama Medical University, 38 Morohongou, Moroyama, Irumagun, Saitama, 350-0495, Japan.
authors: Yasuhiro
authors: Y
authors: Ohara
authors: Department of General Surgery, Saitama Medical University, 38 Morohongou, Moroyama, Irumagun, Saitama, 350-0495, Japan.
authors: Nozomi
authors: N
authors: Shinozuka
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000150:complications*; D005260:Female; D006801:Humans; D007416:Intestinal Perforation / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011182:Postoperative Care; D012008:Recurrence; D012307:Risk Factors
keywords: Adjuvant chemotherapy; Colorectal cancer; Colorectal perforation; Recurrence