Impact of Contrast-Enhanced Intraoperative Ultrasound on Operation Strategy in Case of Colorectal Liver Metastasis

Abstract

Background Surgical treatment is the only option for long-term survival in patients with colorectal liver metastasis (CRLM). Contrast-enhanced CT and MRI are usually used for preoperative liver imaging. The initial surgical strategy for liver resection is based upon these findings. Further optimization of the surgical strategy by contrast-enhanced intraoperative ultrasound (CE-IOUS) might further improve the surgical outcome. Purpose To evaluate the current impact of CE-IOUS with SonoVue® on the initial surgical strategy for CRLM. Material and Methods Eighty-six consecutive patients undergoing open liver resection for CRLM were evaluated retrospectively over a 2.5-year period. The patients underwent 97 operations. Preoperative staging was performed with contrast-enhanced CT in all patients and MRI was available in 66 of 86 patients. CE-IOUS was performed in all patients according to a standardized examination technique. Curved array and linear transducers were used. CRLM were identified in venous phase as hypovascular lesions. CE-IOUS findings were compared with preoperative staging. Results Combined CT/MRI identified preoperatively 328 CRLM (mean 3.4, range 0-14). Seventy-two additional lesions (18%) were identified in 38 patients during the operation. Intraoperatively 41 additional CRLM in 20 patients were identified by inspection, palpation, and CE-IOUS (10%), and another 31 CRLM in 17 patients were identified by CE-IOUS alone (8%). All additional CRLM detected by CE-IOUS were confirmed by histology if resection was performed. CE-IOUS changed planned operation strategy in 29.9% of operations. A larger resection was necessary in 13.4% of the cases, reduced liver resection was found sufficient in 11.3%, and 5.2% were found inoperable. For patients diagnosed preoperatively with solitary lesions CE-IOUS changed operation strategy in 19% and radical tumor resection would have failed in 4.8% without CE-IOUS. Conclusion CE-IOUS is essential to ensure optimal and complete tumor resection both in patient with solitary CRLM and multiple metastases.

Is intraoperative ultrasound still useful for the detection of colorectal cancer liver metastases?

“…The results of intraoperative contrast-enhanced US (CE-IOUS) are controversial. 25 Schulz et al 26 found 31 additional metastases over 369 tumors (8%) by using intraoperative CE-IOUS. These findings were not confirmed by Ferrero et al 10 or Torzilli.…”

Aggressive Treatment of Patients with Metastatic Colorectal Cancer Increases Survival: A Scandinavian Single-Center Experience

“…The assessment included computed tomography (CT) of the abdomen and chest with the addition of magnetic resonance (MR) or ultrasonography with contrast when resectability could not be determined after CT. Positron emission tomography (PET) became available in 2009 and was used to assess extrahepatic disease in selected cases. Intraoperative contrast-enhanced ultrasonography (CEU) was used in every procedure after 2007 to assess resectability and tumor expansion as previously described [10]. Preoperative carcinoembryonic antigen (CEA) levels were determined in all patients in the most recent 5-year period.…”

Intraoperative ultrasound for the colorectal surgeon: current trends and barriers

“…Planning for the optimal treatment approach for CRLM, both operative and non‐operative, requires accurate assessment of liver lesions and liver parenchyma . The ability of a surgeon to assess whether lesions are resectable impacts on patient prognosis, as surgical resection is the main determinant of long‐term outcome in this setting .…”