Laparoscopic ultrasound for the detection of hepatic metastases during laparoscopic colorectal cancer surgery

The value of contrast-enhanced laparoscopic ultrasound during robotic-assisted surgery for primary colorectal cancer

AIM

The aim of this study was to assess the potential clinical value of contrast enhanced laparoscopic ultrasonography (CE-LUS) as a screening modality for liver metastases during robotic assisted surgery for primary colorectal cancer (CRC).

METHOD

A prospective, descriptive (feasibility) study including 50 consecutive patients scheduled for robotic assisted surgery for primary CRC. CE-LUS was performed by 2 experienced specialists. Only patients without metastatic disease were included. Follow-up was obtained with contrast-enhanced CT imaging at 3 and 12 months postoperatively.

RESULTS

Fifty patients were included; 45 patients were available for final analysis. The patients were equally distributed between stage I, II, and III according to the TNM classification system. No liver metastasis was detected during LUS and CE-LUS. CE-LUS was easy to perform and there was no complication. Follow-up revealed no liver metastasis in any of the patients.

CONCLUSION

CE-LUS did not increase the detection rate of occult liver metastasis during robotic assisted primary CRC surgery. The use of CE-LUS as a screening modality for detection of liver metastasis cannot be recommended based on this study, but larger controlled studies on high-risk patients seem relevant.

Intraoperative ultrasound for the colorectal surgeon: current trends and barriers

Up to two thirds of patients diagnosed with colorectal cancer (CRC) develop colorectal liver metastases (CRLMs) and one quarter of patients present with synchronous metastases. Early detection of CRLM widens the scope of potential treatment. Surgery for CRLM offers the best chance of a cure. Current preoperative staging of CRC relies on computerized tomography and magnetic resonance imaging. Intraoperative ultrasound (IOUS) scans and contrast-enhanced IOUS (CE-IOUS) have been demonstrated to detect additional metastases not seen on routine preoperative imaging. IOUS is not widely used by colorectal surgeons during primary resection for CRC. Confident use of IOUS/CE-IOUS during primary resection of CRC may improve decision-making by providing the most sensitive form of liver staging even when compared with magnetic resonance imaging. This may be particularly important in the era of laparoscopic resections, where the colorectal surgeon loses the opportunity to palpate the liver. There are several implied barriers to the routine use of IOUS/CE-IOUS by colorectal surgeons. These include time pressure, familiarity with techniques, a perceived learning curve, cost implications and limitation of the modality due to operator variations. Inclusion of IOUS in the training of colorectal surgeons and further investigation of potential benefits of IOUS/CE-IOUS could potentially reduce these barriers, enabling usage during primary resection for CRC to become more widespread.

Intraoperative Ultrasound as a Screening Modality for the Detection of Liver Metastases during Resection of Primary Colorectal Cancer - A Systematic Review

Colorectal cancer (CRC) is one of the most common cancer diseases worldwide. One in 4 patients with CRC will have a disseminated disease at the time of diagnosis and often in the form of synchronous liver metastases. Studies suggest that up to 30% of patients have non-recognized hepatic metastases during primary surgery for CRC. Intraoperative ultrasonography examination (IOUS) of the liver to detect liver metastases was considered the gold standard during open CRC surgery. Today laparoscopic surgery is the standard procedure, but laparoscopic ultrasound examination (LUS) is not performed routinely. Aim To perform a systematic review of the test performance of IOUS and LUS regarding the detection of synchronous liver metastases in patients undergoing surgery for primary CRC. Method The literature was systematically reviewed using the search engines: PubMed, Cochrane, Embase and Google. 21 studies were included in the review and the key words: intraoperative ultrasound, laparoscopic ultrasound, staging colon and rectum cancer. Results Intraoperative ultrasound showed a higher sensitivity, specificity, positive predictive value and overall accuracy for the detection liver metastases during surgery for primary CRC, compared to preoperative imaging modalities (ultrasound, computed tomography (CT) and contrast-enhanced computed tomography (CE-CT)). LUS showed a higher detection rate for liver metastases compared to CT, CE-CT and magnetic resonance imaging (MRI). Conclusion This systematic review found that both IOUS and LUS had a higher detection rate regarding liver metastases during primary CRC surgery, especially liver metastases<10 mm in diameter, when compared to US, CT, CE-CT and MRI.

[The role of laparoscopy assessing the resectability of hepatic malignancies]

INTRODUCTION

Regarding the prognosis of hepatic malignancies, surgical resection can provide a 40% 5-year survival, however liver transplantation (OLTX) shows even better results. Unfortunately, many patients have non-resectable disease due to either the number and the position of the tumours or its distant spread. It is relatively frequent that it turns out only at the time of the surgical exploration that the patient is inoperable. Hence, in addition to preoperative clinical evaluation and imaging, laparoscopy can be valuable in further staging and assessment of resectability in selected cases.

METHODS AND PATIENTS

310 patients underwent hepatic resection between 1 January 2000 and 31 March 2006. A retrospective analysis was carried out of 39 patients, who underwent laparoscopy prior to the planned hepatectomy. 22 patients (56%) were diagnosed with hepatocellular carcinoma (HCC), while 17 patients (44%) had hepatic metastases.

RESULTS

Altogether 70% of the patients were found to have non-resectable tumour on laparoscopy. However, when these patients underwent laparotomy, non-resectable disease was found in 50% of them. Laparoscopy was helpful to demonstrate non-resectability of the tumour when carcinosis peritonei or multifocal lesions were present, but central or venous invasion could not be assessed adequately with this technique.

CONCLUSION

Laparoscopy can be an important component of the preoperative staging of malignant hepatic tumours. Further, it can help to avoid unnecessary laparotomies. However, this procedure is recommended in selected patients only, and its general use is not indicated.

Laparoscopy for metastatic colorectal cancer

Patients with metastatic disease from colorectal cancer are now living twice as long as they were one decade ago. With this increasing life expectancy, we are beginning to see these patients strive for an acceptable and improved quality of life. Medical advances have led to unanswered questions regarding the role of surgery in metastatic colorectal cancer. Despite the increasing application of laparoscopy for primary treatment of colorectal cancer, the appropriate role for laparoscopy in patients with stage IV disease has yet to be defined. This review addresses this topic and suggests treatment algorithms for patients with metastatic colorectal cancer. While unresectable, metastatic colorectal cancer remains incurable at the current time, continued advances will inevitably challenge this presumption and it is crucial to outline the role of laparoscopy in this patient population.

The role of echo-laparoscopy in abdominal surgery: five years' experience in a dedicated center

BACKGROUND

For more than 20 years intraoperative ultrasonography (IOUS) has been considered an important diagnostic tool in abdominal surgery. In the last few years, with the spread of laparoscopic surgery, echo-laparoscopy (LIOUS) has gradually replaced open ultrasonography, aiming to achieve similar results.

METHODS

LIOUS was performed using an ALOKA 5.500 device, provided with a linear flexible laparoscopic probe that was compatible with a 10-mm port. IOUS was performed by means of a linear side-view, T-shaped or microconvex probe. The probes were sterilized with hydrogen peroxide. No water bath was used during the surgical examination, but full contact of the probe with the surface of the involved organ was always attempted. From 2001 to 2005, 36 liver resections, 40 pancreas procedures, 203 procedures for suspected common bile duct calculi, 541 colon and 82 stomach resections, and 82 adrenal surgery procedures were performed. IOUS or LIOUS was performed in 432 patients (43.8%). All livers and pancreases underwent intraoperative ultrasound, while biliary, colonic, gastric, and adrenal pathologies were selectively studied when there were doubts about the location and extension of the disease.

RESULTS

IOUS and LIOUS were valuable diagnostic procedures, supplying relevant clinical information in 65.1% of the patients and modifying the surgical approach in 17.2%. LIOUS was used instead of cholangiography to study bile ducts when lythiasis was suspected, achieving high diagnostic specificity (98%) and accuracy (100%). Surgical anatomy of the bile ducts was correctly identified by LIOUS in every case.

DISCUSSION

In our experience IOUS and LIOUS were of the utmost importance in better defining staging of disease, infiltration of neighboring structures, number and size of nodular lesions, and anatomy of the hepatic pedicle and intrahepatic structures, thus making it possible to more accurately plan surgical procedures.

Laparoscopic liver resections

Though still practiced in only a few centres worldwide, laparoscopic liver resections, particularly left hepatectomy offer advantages over the conventional open approach in two important respects: reduced operative blood loss and lower major postoperative morbidity. Two approaches are used: the totally laparoscopic and the hand-assisted technique, which in the author's opinion facilitates both the execution and safety of these procedures, especially major resection of the right liver (right hepatectomy and pluri-segmentectomies). Technologies, which have enabled hepatic resections include: laparoscopic contact ultrasound, linear cutting staplers, ultrasonic dissection, LigaSure and TissueLink. The components operative steps necessary for these resections as practised by the author are described in this review.

Diagnostic laparoscopy: indications and benefits

BACKGROUND

The increased availability of treatment options for gastrointestinal cancer, necessitates precise preoperative staging. Laparoscopy can be useful for establishing the diagnosis and staging of cancer. However, there is an ongoing discussion as to whether staging laparoscopy provides additional results despite newly developed imaging tools.

METHODS

A systematic review of relevant literature was undertaken. The strength of evidence was classified according to the North of England Evidence Based Guidelines Development Project. Medline and manual searches were carried out to identify all published manuscripts of clinical trials that dealt with staging laparoscopy. Systematic quality review of those publications was used to verify staging accuracy, complications and trocar metastases.

RESULTS

Only one randomized trial was performed in gynaecological cancer. In cervical cancer, as a result of this study, staging laparoscopy remains unproven. In gastrointestinal cancer (oesophageal, gastric, pancreatic, liver and colorectal cancers) only prospective and retrospective observational studies are available with an evidence-based level of grade B. As a result of these trials, staging laparoscopy, in a well-defined group of patients with locally advanced cancer, is recommended.

CONCLUSION

The effects of surgical staging in gynaecological cancer must be kept in mind but cannot be transferred to gastrointestinal cancer in general. Further studies are required to answer those questions.

Laparoscopic ultrasonography and biopsy of hepatic tumors in 310 patients

BACKGROUND

Laparoscopic ultrasonography is increasingly being recognized as an important tool in the evaluation of patients with possible hepatic tumors. The aim of this paper is to describe the technical aspects of imaging and biopsy based on our experience in 310 patients with 1,080 primary and metastatic liver tumors within a 6.5-year period.

METHODS

A 10-mm rigid or flexible, 7.5 MHz linear, side-viewing laparoscopic ultrasonography probe was used for imaging, and an 18G spring-loaded core biopsy gun was used for tissue diagnosis.

RESULTS

There were no complications. The entire liver was imaged using a right subcostal port. Using a free-hand technique, the needle was best targeted into the lesion when inserted parallel to the plane of the transducer. The rigid transducer was found to be more convenient to guide needle placement.

CONCLUSIONS

The use of this minimally invasive technique avoids laparotomy in many patients undergoing staging of malignancy and also offers increased sensitivity for tumor detection compared with conventional imaging modalities.

Utility of intraoperative liver ultrasound

Intraoperative ultrasound has become an essential tool for the surgeon in the field of hepatobiliary surgery. No preoperative study has been able to duplicate the sensitivity and specificity of IOUS in the identification of occult lesions. With recent improvements in technology, IOUS has now become an indispensable means of defining the extent of disease and respectability, and providing a guide to anatomic and nonanatomic hepatic resections and minimally invasive and percutaneous ablative techniques.

Management of colorectal liver metastases

Hepatic metastases occur in 60% of patients following resection for colorectal cancer. Liver resection is the only curative option, with one third of resected patients alive at five years. In those developing recurrence in the liver following resection, further liver surgery may be curative, with similar 5 years survival rates of about 30%. Until recently surgery was feasible in only 15-25% of patients with colorectal liver metastases. New strategies, such as downstaging chemotherapy, portal vein embolization and two-stage hepatectomy, may increase the resectability rate by 15%. Earlier detection of liver metastases would increase resectability, although good follow-up trials are lacking. Once suspected, colorectal liver metastases are staged by spiral CT, CT portography and MRI, which have similar overall accuracies. Mortality following liver resection is less than 5% in major centres, with a morbidity rate of 20% to 50%. Prognostic scoring systems can be used to predict the likely cure rate with resection. Pulmonary metastases occur in 10-25% of patients with resected colorectal cancer, but are limited to the lung in only 2% of cases. In these selected cases surgery provides long-term survival in 20-40%, and repeat lung resection has shown similar rates. For patients with unresectable disease, chemotherapy and ablation techniques have been demonstrated to prolong survival, although chemotherapy alone has been shown to improve quality of life.

The role of laparoscopy in the multimodality treatment of colorectal cancer

Ten years after the first reports of laparoscopic techniques in colorectal surgery the precise role for these approaches in future colorectal practice as still to be defined. However, it seems most unlikely that the application is going to disappear. Laparoscopic colectomy is undoubtedly a complex. time-consuming procedure and it is clear that the technique is intolerant of difficult cases and will likely remain thus. Therefore. the potential advantages of laparoscopy do not as yet appear to be attainable across the board in colorectal resection. Such generalized advantage may, however, be tantalizingly close. Although many studies have failed to show major benefits for laparoscopy in terms of postoperative recovery, it must be remembered that most of these have been of insufficient statistical power to settle the issue. What is clear to all involved in the field is that very many patients do gain major benefit from the minimally invasive approach. The challenge for the future lies in developing the technology to such a point that these benefits for patients are more reproducible. The requirement for a significant abdominal incision to deliver an intact specimen represents a significant hurdle in this regard. The importance of pathological staging for colorectal cancer at present mandates retrieval of an intact specimen. It is of course possible that radiological staging may develop to such a point that surgeons need only remove the lesion with minimal attention to lymphadenectomy. Alternatively, new adjuvant therapies may arrive that, by virtue of increased efficacy and low side-effect profiles, may be applicable to all but the earliest lesions. Finally, increasing health awareness and application of screening programs may lead to a preponderance of large polyps and preinvasive lesions for which a more limited resection may be appropriate. Obviously these scenarios remain almost entirely speculative. However, the trend towards less invasive local therapy for colorectal cancer seems inexorable, and we firmly believe that laparoscopy will come to play an increasing role. Finally, we suggest that the oncological safety of laparoscopy is of less concern than was the case some years ago. The specter of port-site metastasis, once so alarming, has faded. It is now apparent from all of the larger scale studies that port-site metastases are not a significant issue in the presence of adequate training and laparoscopic skills. Almost without exception, the accumulating evidence seems to point to equivalence in terms of disease-specific recurrence and survival between patients treated using conventional and laparoscopic techniques. We foresee these findings being confirmed by the North American and European trials.

Laparoscopic ultrasonography: a training model

PURPOSE

The purpose of this study was to develop a surgical training program and to test the accuracy of laparoscopic ultrasound in detecting injected lesions in pig livers.

METHODS

Pig livers were divided into eight segments and injected with Surgilube "malignant" and silicone "benign" lesions. All were examined by laparoscopic ultrasound followed by liver explantation to confirm results. First, a pilot study was conducted on six swine by injecting Surgilube lesions and performing laparoscopic ultrasound through 3 different ports (left upper quadrant (I), umbilicus (II), and right lower quadrant (III)) to determine per-segment accuracy and to optimize port placement. Second, blinded injection of Surgilube and silicone implants was done on 18 pigs with laparoscopic ultrasound conducted through the two most accurate ports from the pilot study. This model was then tested during a resident training workshop.

RESULTS

In the pilot study, per-lesion and per-segment sensitivity was 96 percent, with no difference among the three ports used. Ports I and II were chosen for the blinded study for their convenience in performing laparoscopic colectomy. In the blinded study, per-segment sensitivity, specificity, and accuracy were 97 percent, 94 percent, and 96 percent and 99 percent, 94 percent, and 97 percent for ports I and II, respectively. At the conclusion of a pilot workshop, trainee per-segment sensitivity, specificity, and accuracy were 60 percent, 80 percent, and 70 percent, respectively. The major difficulty was differentiating benign from malignant lesions.

CONCLUSIONS

A useful liver laparoscopic ultrasound training model for surgeons was developed with good preliminary results. It is anticipated that further training will enhance laparoscopic ultrasound accuracy rates before application of this modality in humans.