CLINICAL STUDIES Intra-operative ultrasound for detection of liver metastases from colorectal cancer Gianluca Mazzoni 1 , Alessandro Napoli 2 , Saverio Mandetta 1 , Michelangelo Miccini 1 , Diletta Cassini 1 , Matteo Gregori 1 , Lidia Colace 1 and Adriano Tocchi 1 1 Department of Surgery, ‘La Sapienza’ University Medical School, Rome, Italy 2 Department of Radiology, ‘La Sapienza’ University Medical School, Rome, Italy Keywords colorectal cancer – intra-operative ultrasound – liver metastases Correspondence Adriano Tocchi, MD, FACS, Via Bruno Bruni, 94, 00189 Rome, Italy Tel: 1 39649970365 Fax: 1 39649970365 e-mail: adriano.tocchi@uniroma1.it Received 14 March 2007 accepted 14 June 2007 DOI:10.1111/j.1478-3231.2007.01583.x Abstract Objective: The aim of this study was to evaluate the accuracy of intra-operative ultrasound (IOUS) imaging in detecting liver secondaries at the time of primary colorectal surgery and to evaluate the impact of IOUS on patient management. Methods: Data from 167 patients with primary colorectal cancer who were admitted for elective surgery between January 1995 and December 2003 were prospectively evaluated and analysed. All patients underwent pre-operative abdominal ultrasonography (US) and computed tomography (CT), as well as IOUS. The final diagnosis of liver metastases was made by means of histological examination of either biopsy or surgical specimens. The sensitivities of pre- operative US and CT were compared with the sensitivity of IOUS, referred to histology. Changes in surgical management owing to IOUS findings were noted. Results: IOUS supplied additional information in the case of 31 patients. In 28 of these patients, this information had a major impact on the intra-operative strategy, in that the procedure was altered. Conclusions: IOUS is safe, simple to perform and more accurate than pre-operative imaging. It reduces the number of patients subjected to superfluous surgery. The use of IOUS is therefore encouraged during colorectal cancer surgery. The major risk for recurrence in patients with color- ectal cancer remains disseminated disease. The liver is involved in up to two-thirds of patients who die from colon cancer (1). Of the 260 000 colorectal carcinoma patients diagnosed in Europe each year, approximately 32 000 present with synchronous hepatic metastases (2, 3). Furthermore, after resection for cure of color- ectal cancer, metachronous liver metastases are re- ported to occur in about 20% of patients: 8% within 2 years (4, 5). Because of the short interval, these tumours are believed to be metastases that were over- looked at the time of the previous surgery (3, 6). Hepatic resection is the most effective therapy for a subset of patients with colorectal carcinoma metastatic to the liver. However, strict selection criteria are necessary because there is no survival benefit if resi- dual disease remains after hepatectomy (7–9). Experi- mental studies suggest that the probability of dissemination of solid tumours is lower when fewer tumour cells have been present for a short time (10, 11). It is thus conceivable that in the case of liver metastasis, the best opportunity for cure through resection is when liver secondaries have been found earlier in their natural history, when they are small and slow to disseminate. How to assess the hepatic spread from colorectal cancer is a subject of discussion, and patients are currently screened by a number of diag- nostic procedures (3, 12). Despite careful pre-opera- tive staging, the surgeon is often faced with a discrepancy between pre-operative imaging results and intra-operative findings (9, 13, 14). Furthermore, metastases may be missed at the time of surgery because they are too small to palpate or too deep in the hepatic substance or are situated in a part of the liver that is inaccessible, or because the liver is surrounded by adhesions (7, 15). Therefore, better detection methods are still needed. Intra-operative ultrasound (IOUS) has been de- monstrated to be a sensitive means of detecting meta- static liver disease (16–18). We report data from a prospective series of patients undergoing elective re- section of primary colorectal cancer, with routine Liver International (2007) 88 c  2007 The Authors. Journal compilation c  2008 Blackwell Munksgaard Liver International ISSN 1478-3223