Multidisciplinary Treatment for Colorectal Peritoneal Metastases: Review of the Literature

Abstract

Peritoneum is one of the common sites of metastasis in advanced stage colorectal cancer patients. Colorectal cancer patients with peritoneal metastases (PM) are traditionally believed to have poor prognosis, which indicates it is of no value to adopt surgical treatment. With the advancement of surgical techniques, hyperthermic intraperitoneal chemotherapy (HIPEC), and multidisciplinary treatment in recent years, the cognition and treatment strategies of colorectal peritoneal metastases (CPM) have changed dramatically. In terms of prognosis, CPM under the palliative systemic treatment shows an inferior outcome compared with nonperitoneal metastasis. Nevertheless, some CPM patients amenable to the complete peritoneal cytoreductive surgery (CRS) combined with HIPEC may achieve long-term survival. The prognostic factors of CPM comprise peritoneal carcinomatosis index (PCI), completeness of cytoreduction score (CC score), the presence of extraperitoneal metastasis (liver, etc.), Peritoneal Surface Disease Severity Score (PSDSS), Japanese peritoneal staging, and so forth. Taken together, literature data suggest that a multimodality approach combining complete peritoneal CRS plus HIPEC, systemic chemotherapy, and targeted therapy may be the best treatment option for PM from colorectal cancer.

Exosomes Derived from Hypoxic Colorectal Cancer Cells Transfer Wnt4 to Normoxic Cells to Elicit a Prometastatic Phenotype

“…Approximately 50-60% of patients with CRC present with metastases at initial diagnosis 3. Because metastasis is the leading cause of CRC treatment failure, there is an imperative need to elucidate the molecular mechanisms driving this process 4. A hypoxic tumour microenvironment, which is defined as a condition in which the oxygen pressure in the tumour tissue is less than 5 to 10 mm Hg, is extremely important for cancer metastasis 5, 6.…”

Diagnostic value of whole-body MRI with diffusion-weighted sequence for detection of peritoneal metastases in colorectal malignancy

“…Patients with small-volume tumor (PCI < 10) achieved a higher 5-year survival rate than patients with a PCI ranging from 10 to 20, or > 20 ( P < 0.05). PCI < 20 is recommended as one criterion of the principle of CRS and HIPEC in patients with colorectal peritoneal metastatic lesions 23 , 24 . For patients with tumors that are too extensive and cannot be adequately cytoreduced, good preoperative imaging helps prevent unnecessary surgeries.…”

Liver Metastases and Peritoneal Carcinomatosis in A Sigmoid Adenocarcinoma Should We Perform Colectomy in A Stage IV Colorectal Cancer?

“…However, recently it has been published that if the patient has<3 liver metastases as well as a PCI<12 or good response after chemotherapy, the surgical decision must be individualized [2].…”