Peritoneal cytology as an indicator of peritoneal metastases in colorectal cancer

J Surg Oncol. 2021 Sep;124(3):361-366. doi: 10.1002/jso.26520. Epub 2021 May 7.

Abstract

Background: In the management of peritoneal metastases from colon and rectal cancer, the most favorable results are reported with an aggressive combined treatment on patients who have a small extent of the disease. A test to detect occult peritoneal metastases would greatly facilitate the management of this component of colorectal dissemination.

Methods: Currently, the standard test by which to confirm the diagnosis of the peritoneal spread of colorectal cancer is peritoneal cytology. To study the utility of this test, we gathered information from patients with biopsy-proven peritoneal metastases. The clinical, histologic, and treatment-related features of these patients at the time of a cytoreductive surgery were statistically correlated with the results of the peritoneal cytology test.

Results: Forty-nine patients with colorectal cancer peritoneal metastases and a peritoneal cytology determination at the time of a cytoreductive surgery were available for analysis. Twenty-eight patients (55.1%) had a positive test. Patients with a high peritoneal cancer index and mucinous histology were most likely to have positive peritoneal cytology.

Conclusion: Peritoneal cytology identified patients with mucinous histology and a large extent of disease but was consistently negative in patients who had a small extent of disease compatible with a favorable response to treatment.

Keywords: FOLFOX; HIPEC; cytoreductive surgery; mucinous adenocarcinoma; perioperative chemotherapy; peritoneal cancer index.

MeSH terms

  • Adult
  • Ascitic Fluid / pathology
  • Biopsy
  • Colorectal Neoplasms / drug therapy
  • Colorectal Neoplasms / pathology*
  • Colorectal Neoplasms / surgery
  • Cytoreduction Surgical Procedures
  • Female
  • Humans
  • Male
  • Middle Aged
  • Neoadjuvant Therapy
  • Peritoneal Neoplasms / drug therapy
  • Peritoneal Neoplasms / pathology
  • Peritoneal Neoplasms / secondary*
  • Peritoneal Neoplasms / surgery
  • Young Adult