Advances in hepato–pancreato biliary surgery

Abstract

The Americas Hepato–Pancreato Biliary Association (AHPBA) Annual 2011 Meeting provided a forum for discussion of multidisciplinary advances surrounding six tracks including the liver, biliary system, liver transplantation, pancreas, imaging and biomedical engineering and general hepato–pancreato biliary (HPB) surgical disease. The meeting and postgraduate courses attracted the largest ever attendance and participation in the AHPBA annual meeting, including field leaders and participants from across North, Central and South America who interchanged clinical and scientific knowledge, and discussed advances in technology, care and outcomes for treatment of HPB diseases. The AHPBA Foundation, established in 2010, announced progress toward support of meritorious research in HPB disease and enrichment of educational programs. HPB fellowship graduates were recognized, marking successful establishment of the AHPBA as an important body guiding HPB education and training in the USA and the Americas.

The Americas Hepato–Pancreato Biliary Association (AHPBA) held its Annual 2011 Meeting in Miami Beach, this year planned by the 19 program committee members led by Chair Michael D’Angelica, and Co-Chair Charles Vollmer, with input from the 12 Committees, focusing on six tracks: the liver, biliary system, liver transplantation, pancreas, imaging and biomedical engineering, and general hepato–pancreato biliary (HPB) surgical disease. The meeting spanned 5 days and was filled with social activities, committee meetings and 4 days of scientific programs. More than 1000 participants from numerous countries were present, including 54 invited faculty and speakers. Lectures were followed by lively discussions, and the latter days of the meeting featured presentations derived from abstract submissions from young investigators and general members. Poster presentations included dedicated oral walking presentations, thus increasing the exposure and impact of member submissions. The outgoing AHPBA president, Reid B Adams, spoke of the association’s progress in membership, teaching (HPB fellowship), advancement of science (AHPBA Foundation), and the growing role of the AHPBA in ‘setting the course’ of HPB training and surgery. He warmly welcomed Jean-Nicolas Vauthey, the incoming president of the organization, who will set the future course of leadership in teaching, science and advancement for the AHPBA in the coming year.

Included in the extensive program was the AHPBA postgraduate sequence which covered three major areas entitled:

• • Advances in preoperative evaluation and surgical techniques for HPB malignancies;

• • Innovative approaches;

• • Surgical techniques.

This article will primarily summarize the post-graduate course. Although the course focused primarily on cancer imaging and interventions and less on benign disease (a critical component of the meeting), this provides an overview of the detail and complexity of the Annual Meeting as whole.

Advances in preoperative evaluation & surgical techniques for HPB malignancies

The first postgraduate course was co-chaired by Jean-Nicolas Vauthey from MD Anderson Cancer Center (TX, USA) and Norihiro Kokudo from the University of Tokyo (Japan).

The recognized authority on contrast-enhanced ultrasound, Stephanie Wilson (University of Calgary, Calgary, Canada), presented an overview and new data concerning the utility of this modality in staging and characterizing a variety of liver tumors. Calling on her extensive experience, this talk focused on the utility of contrast-enhanced ultrasound detection and especially characterization of liver tumors. Real-time, dynamic imaging, which is not restricted to views of specific time points after contrast injection as with CT or MRI imaging (particularly in the case of hepatocellular tumors in patients with cirrhosis), allows for observation of the characteristics of enhancement that do not follow ‘the rules’ of duration of hyperintense enhancement and late phase washout of classical hepatocellular carcinomas, permitting characterization of the more difficult atypical lesions.

Yun Shin Chun from Fox Chase Medical Center (PA, USA) discussed advances in radiographic assessment of the response of colorectal liver metastases (CLM) to chemotherapy including bevacizumab. This talk focused on new data published in Journal of American Medical Association by our group [1]. In short, among patients with CLM treated with bevacizumab, response evaluation criteria in solid tumors (RECIST) are of little clinical use because tumor size changes do not reflect the spectrum of response to this class of agents. Rather, morphologic criteria correlate highly with survival, including change in the attenuation of the CLM, assessment of the tumor–liver interface and evolution of the peripheral enhancement of the tumor. RECIST criteria did not predict outcome in patients who underwent complete resection of CLM, or in those with unresectable, advanced disease, whereas the morphologic criteria were prognostic both in resected and unresected patients, providing a powerful predictive tool for surgeons and oncologists to analyze imaging in operable and inoperable patients. Furthermore, morphologic response correlated to pathologic response, the most powerful predictor of survival in patients who undergo resection of CLM following chemotherapy [2].

Thomas Aloia (MD Anderson Cancer Center) next provided a very balanced assessment of the roles of transarterial embolic approaches to liver tumors. This refreshing review of these therapies reiterated successes that are frequently touted with regard to intra-arterial therapy, balanced against the immaturity of much of the data regarding the use of newer embolic approaches, such as radioembolization, for many tumor types.

Gauri Varadhachary (MD Anderson Cancer Center) followed with a discussion of a well-defined sequence of treatments designed to optimize the outcome for patients with ‘borderline’ resectable pancreatic adenocarcinoma. Such patients were defined in a clinically useful way to encompass the spectrum of patients seriously considered for pancreaticoduodenectomy – those who are clinically not ideal for surgery because of comorbidity or poor nutrition (despite anatomically approachable tumors), and those with anatomically situated tumors that do not meet the standard definition of ‘resectable.’ The entire cohort was treated similarly, with a sequence of:

• • Imaging and clinical evaluation;

• • Multidisciplinary evaluation;

• • Systemic therapy (typically gemcitabine alone or in combination with a second agent);

• • Restaging;

• • Chemoradiotherapy;

• • Restaging after a break of approximately 6 weeks;

• • Surgery if performance status and imaging support operation.

This approach not only allows redirection of the care plan at each restaging point, but optimizes outcome, since resected patients have, in the experience of our institution, a median survival duration of 40 months (similar to the survival duration in many series for patients with resected pancreatic cancer treated with adjuvant therapy) [3]. This neoadjuvant approach to an objectively defined group of patients with advanced disease allows for selection of, and surgical therapy in, the group most likely to benefit from pancreatic resection.

Innovative approaches

The second session was chaired by William Jarnagin (Memorial Sloan–Kettering Cancer Center, NY, USA) and Timothy Pawlik (Johns Hopkins University, MA, USA) and focused on approaches and technologies designed to improve outcomes in HPB surgery. The first presentation from Jeff Barkun (McGill University, Quebec, Canada) described the difficulties uniting innovation and patient care as new technologies are evaluated and integrated into practice. New devices and instruments are continuously developed, testing is performed, and these innovations are approved and adopted into practice with variable levels of quality assurance that the best interests of the patient are being served by the introduction of these methods or instruments. Radiofrequency ablation (RFA) is an example of a new technology of great utility that was disseminated into practice before its limitations (a significant local recurrence rate for treatment of some tumors such as CLM and large tumors) versus its advantages (in particular its utility in cirrhotic patients with hepatocellular carcinomas) were defined. This presentation flowed into the next, which was given by Robert Martin (University of Louisville, KY, USA), who described the hopes associated with microwave ablation, as his presentation title ‘New or Déjà vu?’queried. Martin reflected on the hopes of microwaves (faster, larger, more consistent ablation zones and thus more effective tumor destruction than RFA), the potential benefit of an ablation technique that could destroy tumors up to and around larger intrahepatic vessels more effectively than RFA. This ‘hope’ was framed in the perspective of the limited data available regarding actual patient outcomes before this technology was dispersed into the medical community and used without clear evidence of its place in the treatment of the spectrum of liver tumors.

Next, Dominique Elias from the Institut Gustave Roussy (Paris, France) gave a remarkable presentation on innovative strategies for resection of unresectable liver metastases. A wide range of approaches were presented, typically designed to enable resection of extensive or bilateral liver lesions. Established approaches, including downsizing chemotherapy, two-stage resection of bilateral lesions, and resection plus RFA, were discussed. In addition, approaches such as pre-ablating the transection line and cutting through the ablated tumor were discussed. Elias is also well known for the use of intra-arterial chemotherapy delivered to the liver via a hepatic artery portacath inserted surgically. He reiterated the impressive results of their group using this approach with intra-arterial oxaliplatin chemotherapy in downsizing tumors to a resectable size.

I then spoke about the potential approaches to patients with a synchronous presentation of colorectal cancer and liver metastases. The classical approach is described as resection of the primary tumor at one laparotomy, followed at a second operation by resection of liver metastases. In addition, the combined approach is well established, in which both the primary tumor and the liver metastases are resected at a single operation. The reverse approach, that is resection of liver metastases before resection of the primary tumor at a second laparotomy, was proposed by Mentha et al., particularly for patients with rectal primary tumors [4]. The first step proposed was chemotherapy; the first surgical step liver resection, followed by a brief recovery, followed by commencement of radiotherapy to the primary tumor and subsequently by rectal resection. In this way, the most life-threatening disease, liver metastases, would be addressed first with a minimal treatment-free interval from liver secondary treatment to primary treatment. Mentha et al. proposed that addressing the primary first with chemoradiotherapy and surgery would create a significant delay in treatment of otherwise resectable liver metastases, putting the patient at risk of death from disease that could be avoided with the liver-first approach. We built on this concept [5], proposing an additional rationale for the reverse approach, which is the rarity of any primary-tumor related complication following treatment with systemic chemotherapy [6]. In this perspective, we retrospectively analyzed 156 patients with a synchronous presentation of rectal or colon cancer with liver metastases [5]. We used the reverse approach in patients with more liver tumors (median: four) than patients considered for the classic or combined approach and found that mortality was equivalent in the three groups (3% in classic, 5% in combined, and 0% in reverse patients), with similar cumulative morbidity and comparable 5-year overall survival regardless of approach (overall median: 64-month survival, with 5-year overall survival rate of 50%). A growing number of patients with synchronous presentation are being operated on at our institution since introduction of the reverse strategy; only two patients developed primary-related problems after liver surgery; both had rectal tumors that could not be passed with a pediatric colonoscope, thus defining a group that may not be ideal for consideration of reverse strategy. These findings reiterate that priority can be given to the most complex problem (primary or liver), and that these approaches apply not only to patients with rectal but also with colon primaries.

Surgical techniques

The final section was chaired by Thomas Aloia and Jeff Barkun. The first presentation from Norhiro Kokudo discussed the use of intraoperative imaging and the hanging maneuver in liver surgery. Focus on the correct assessment of anatomic variations in portal and hepatic venous anatomy that define transection lines, and the utility of advanced intraoperative ultrasound techniques in defining the retrohepatic dissection for the liver hanging maneuver. This technique was emphasized because of the risk of injury of the proper hepatic vein draining the caudate liver, which, when injured in passing the retrohepatic caval clamp, can cause significant bleeding. Intraoperative ultrasound can be used to identify the location of the caudate vein and the clamp tip, such that the trajectory of the clamp can be adjusted to avoid injury to the vein. This technique has been used in both tumor surgery and importantly in living donor hepatectomy, where minimizing risk to the donor and the donor liver are of paramount importance.

Douglas Evans from the Medical College of Wisconsin (WI, USA) then spoke on vascular resection and reconstruction in the setting of borderline resectable pancreatic cancer. This presentation built upon the definitions and approach discussed by Varadhachary, as Evans refined the anatomical borderline definition and has been a leader in defining the role for vascular resection in pancreatic cancer surgery. Data presented reiterated the fact that resectability of pancreatic cancer is defined by high-quality, cross-sectional imaging, not on palpation in the operating room. Data regarding resection with focus on the importance of the superior mesenteric artery (SMA) margin, reveal that resection and reconstruction of the superior mesenteric vein/portal vein confluence can be accomplished with excellent oncologic outcomes in patients with borderline resectable pancreatic cancer provided that proper SMA dissection is performed and neoadjuvant therapy has been given. Regarding arterial resection, the present recommendations suggest that limited involvement of the hepatic artery (typically at the gastroduodenal artery origin) amenable to short-segment hepatic artery resection and reconstruction constitute the major indication for arterial resection in pancreatic cancer. Results for resection of celiac and SMA resection remain disappointing.

Daniel Cherqui from Weill Cornell Medical Center (NY, USA) then moved to a discussion of living donor liver transplantation, asking the question, ‘Quo Vadis?’ (where are you going?). Difficulties including donor complications and deaths, and poor graft function related to small graft size are obvious points of concern. In addition, the availability of the living donor organ has raised the question of transplantation beyond accepted criteria and whether patients with complications after living donor liver transplantation should be placed ahead of others on the standard transplant list for urgent salvage. From a technical standpoint, advances in technique allow consideration of minimally invasive (laparoscopic) donor hepatectomy with excellent results and lower morbidity for the donor. Improved volumetric/functional assessment based on careful anatomic analysis of the donor allow better assurance of adequate liver function in the donor (postdonation) and the recipient (post-transplant).

The last presentation in this section was given by Michael Kendrick of the Mayo Clinic (MN, USA). This very balanced presentation reflected on the growing experience with laparoscopic pancreaticoduodenectomy. The technical feasibility of the approach is rapidly becoming established but requires several elements including:

• • Appropriate patient selection;

• • Advanced training and experience in open pancreatic surgery;

• • Training and experience in advanced laparoscopic techniques.

Advantages of the approach included remarkable exposure and visualization of the SMA margin for proper oncologic dissection. Limitations included the incidence of pancreatic fistula early in the laparoscopic experience. The addition of the surgical robot for reconstruction was described as a means of facilitating pancreaticojejunostomy because of the additional degrees of freedom given by the robotic instruments, but also limiting the haptic feedback that helps the surgeon (even laparoscopically) sense the consistency of the tissue during reconstruction. There is not yet consensus that the added cost and time associated with use of the robot for pancreaticoduodenectomy is warranted, although laparoscopic HPB surgery is clearly here to stay.

Conclusion

This glimpse of the extensive program highlights the diversity and depth of topics presented by a range of international experts within the AHPBA. The meeting promotes interchange of knowledge, friendship and education across the clinicians and scientists in the hepatic, pancreatic and biliary disciplines. The next AHPBA event will be the 2011 Americas Postgraduate Course, to be held at the Clinica Alemana in Santiago, Chile on 30 June–1 July 2011. This academic and social event will focus on management of benign and malignant hepatobiliary diseases. As a part of the International HPBA, the AHPBA participates in the 10th World Congress of the International HPBA with the European/African/Middle Eastern Hepato–Pancreato Biliary Association and the Asian-Pacific Hepato–Pancreato Biliary Association, which is to be held on 1–5 July 2012 in Paris, France. The vibrant AHPBA/International HPBA continues to provide leadership in education, training and scientific advancement in HPB diseases.

Financial & competing interests disclosure

The author has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.