The importance of integrating diagnostic modalities in patient selection for CRS-HIPEC in colorectal peritoneal metastases

BACKGROUND

Despite thorough preoperative work-up for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), so called open-close (OC) procedures as a result of irresectable disease remain common. Currently, diagnostic laparoscopy (DLS) is considered the gold standard, and consequently overrules the results of computed tomography (CT) scans; however, certain regions of the abdomen are difficult to assess and postoperative adhesion formation may further compromise staging during DLS.

PURPOSE

To determine whether better clinical assessment could be achieved by combining the results of DLS and preoperative CT scans during a multidisciplinary team (MDT) meeting.

MATERIAL AND METHODS

All patients who were eligible for CRS-HIPEC after DLS, but eventually underwent an OC procedure between 2010 and 2018 were selected. Radiological reassessment of CT scans was performed and combined with assessment of the DLS during a MDT meeting. The MDT was blinded for the outcome of the procedure (OC vs. CRS-HIPEC).

RESULTS

The majority of the OC procedures (69%) was correctly predicted by the MDT. In most patients (88%), this conclusion was based on the combination of the radiological and surgical peritoneal cancer index (PCI). CT was particularly accurate for detection of larger tumor deposits in the abdominal regions, as 84%-86% was detected. Assessment of lesions in the small bowel regions is troublesome; 72% of lesions are missed on the preoperative CT scan.

CONCLUSIONS

A combination of radiological and surgical assessment of the PCI may lead to improved preoperative patient selection for CRS-HIPEC.

Communicating imaging findings in peritoneal mesothelioma: the impact of 'PAUSE' on surgical decision-making

The peritoneal cavity is the second commonest site of mesothelioma after the pleural cavity. There are five histological types of peritoneal mesothelioma with variable symptomatology, clinical presentation and prognosis. Cystic mesothelioma is a borderline malignant neoplasm with a favourable prognosis, well-differentiated papillary mesothelioma is generally a low-grade malignancy, and all other varieties such as epithelioid, sarcomatoid and biphasic mesothelioma are highly malignant types of peritoneal mesothelioma with poor prognosis. Malignant peritoneal mesothelioma was considered inevitably fatal prior to the introduction of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in selected cases where long-term survival and cure could be achieved. However, the survival benefits following CRS and HIPEC mainly depend on completeness of cytoreduction, which come at the cost of high morbidity and potential mortality. Using the acronym 'PAUSE', we aimed at describing the key imaging findings that impact surgical decision-making in patients with peritoneal mesothelioma. PAUSE stands for peritoneal cancer index, ascites and abdominal wall disease, unfavourable sites of involvement, small bowel and mesenteric disease and extraperitoneal disease. Reporting components of 'PAUSE' is crucial for patient selection. Despite limitations of CT in accurately depicting the volume of disease, describing findings in terms of PAUSE plays an important role in excluding patients who might not benefit from CRS and HIPEC.