Fig. 24.1
Abdominal and pelvic multidetector computed tomography (MDCT) in a patient with a large colonic tumor (asterisk), which involves duodenum and pancreas (white arrow) and segment VI of the liver (blue arrow) (a and b). Whole-body positron emission tomography shows a focus of intense FDG uptake in the liver and right flexure of the colon (white arrow) (c)
Diffusion-weighted imaging (DWI) is another functional imaging tool for liver tissue characterization and pretreatment response estimation in colorectal metastases. From the DWI-MR images an apparent diffusion coefficient (ADC) can be calculated. The ADC is inversely associated to the cell density, because cellular membranes inhibit water movement. It has been shown that ADC increased within days after chemotherapy [8]. Remarkably, the DWI sequence does not demand the administration of intravenous contrast material.
The diagnostic benefits of positron emission tomography (PET) scan have also been confirmed in patients with colorectal cancer with metastatic disease to the liver and extrahepatic sites, such as lymph nodes, soft tissues, and bones [9] (Fig. 24.1c). However, the main limitation in using PET-CT is its restricted accessibility and high cost. Its use can be justified in the case that the tumor extension was not clearly definable on MDCT or Magnetic Resonance (MR).
Operative Procedure
Definitions
Preoperative Care
To reduce intestinal content, mechanical bowel preparation with an oral phosphate solution is recommend.
Surgical Aspects
Multivisceral resection for locally advanced colorectal cancer offers the chance of long-term cure [11]. However, few reports have discussed the benefit of these complex procedures in association with hepatic resections. Current literature emphasizes the importance of achieving a R0 resection in colorectal cancer surgery. A recent systematic review, found that R0 resection is a strong predictor of outcomes following multivisceral resections. Partial resection is a poor prognostic element for survival, so that even palliation surgery is not a good surgical indication for multivisceral resections, given the morbidity associated with these procedures.
Timing of hepatic resection has been reported to be a significant prognostic factor. Some studies have shown that simultaneous colon and liver resection was a significant poor prognostic factor, associated with high morbidity and mortality. However, since the advances in anesthetic techniques and the improvement in surgical skills, as well as the progress in postoperative care, simultaneous resections can be performed safely with comparable or even better outcomes than staged procedures [3].
Usually, MVR is undertaken prior to liver resection to ensure a R0 margin resection (Fig. 24.2). It’s important to perform routinely intraoperative liver ultrasound to confirm lesions diagnosed preoperatively or to detect new lesions and establish the relationship between the tumor and major intrahepatic vessels and bile duct. Before parenchymal transection, central venous pressure must kept at <5 cm H2O to decrease blood loss. The Pringle maneuver can be applied in cases where bleeding was encountered during the parenchymal transection despite a low central vein pressure.
Fig. 24.2
Colorectal liver metastases in segments III and IV (blue arrows). (a) The asterisk shows a tumor involving ileum, right colon, and the great omentum. The white arrow shows the resection of segment III and atypical resection of segment IV (blue arrow). (b) The colonic tumor was removed with an extended right colectomy, atypical gastrectomy, and the resection of the great omentum
In the case of PC, tumor extent is typically scored during the intraoperative procedure according to the Sugarbaker peritoneal cancer index (PCI) [12]. Cytoreductive surgery should be performed with peritonectomy procedures, as described by Sugarbaker in diseased regions of the abdomen and pelvis [13]. Usually, cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy (HIPEC) is used to treat macroscopic and microscopic disease. Maggiori et al. [4], suggested that patients with a PCI of less than 12 and one or two easily resectable liver metastases should be subjected to a complete surgical resection followed by hyperthermic intraperitoneal chemotherapy.
Short-Term and Long-Term Outcomes
Govindarajan et al. [14] identified 8380 patients who underwent surgical resection for locally advanced adherent colorectal cancer, of whom only 33.3% were managed with MVR, despite improved survival with these types of procedures. Several large population-based studies have demonstrated that increasing hospital and surgeon volumes result in fewer postoperative complications and lower mortality in high-complexity surgical procedures [15]. While CLMVR in colorectal cancer is associated with a significant morbidity rate, perioperative mortality is comparable with previously published data on mortality following MVR in hepatobiliary malignancies, advanced gastric cancer, and neuroendocrine tumors [2, 10, 16–18].
The most common complications are: wound infection, bowel obstruction or ileus, urinary complications, intra-abdominal abscess, anastomotic leak, eventration or dehiscence, intestinal fistula, bleeding, urinary fistula, biliary fistula, and posthepatectomy liver failure. Other complications include leg weakness, medical complications including cardiac and pulmonary morbidity, and venous thromboembolism [10, 16]. A recent study recognized extended multivisceral resection of two or more additional organ, and long operative time, as independent risk factors for intra-abdominal complications or need for relaparotomy in patients with pancreatic malignancies [19]. Another study showed that the resection involving more than four organs was found to be a statistically significant risk factor for developing major complications [10].
Related posts:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
