Role of liver transplantation in the management of metastatic neuroendocrine tumors

Rectal Carcinoid Tumor With Liver Metastases Treated by Local Excision and Orthotopic Liver Transplant With Long-term Follow-up

In patients affected by unresectable liver metastases from neuroendocrine tumor, liver transplant represents currently the only realistic chance for cure. The first attempt to establish selection criteria for liver transplant in patients affected by neuroendocrine tumor liver metastases was made by Mazzaferro and associates in 2007. We report the case of a 46-year-old man who came to our institution in 2006 with right upper quadrant abdominal pain. Diagnosis of rectal neuroendocrine tumor with bilobar liver nodules was made; the patient underwent transanal local resection. A liver biopsy confirmed the metastatic nature of the hepatic lesion, showing a low-grade neuroendocrine tumor (G1, proliferation index Ki-67 <2%). The patient underwent 2 sessions of transarterial chemoembolization that resulted in stable disease. Afterward, the patient underwent a liver transplant, using the piggyback technique without a venous-venous bypass. His postoperative course was uneventful. The patient has been disease-free for 3 years. Posttransplant treatment has played a key role in increasing the overall survival of the patient and assuring him a good quality of life. He died 9 years (102 mo) after liver transplant.

Treatment options for PNET liver metastases: a systematic review

BACKGROUND

Pancreatic neuroendocrine tumors (PNETs) are rare pancreatic neoplasms. About 40-80% of patients with PNET are metastatic at presentation, usually involving the liver (40-93%). Liver metastasis represents the most significant prognostic factor. The aim of this study is to present an up-to-date review of treatment options for patients with liver metastases from PNETs.

METHODS

A systematic literature search was performed using the PubMed database to identify all pertinent studies published up to May 2018.

RESULTS

The literature search evaluated all the therapeutic options for patients with liver metastases of PNETs, including surgical treatment, loco-regional therapies, and pharmacological treatment. All the different treatment options showed particular indications in different presentations of liver metastases of PNET. Surgery remains the only potentially curative therapeutic option in patients with PNETs and resectable liver metastases, even if relapse rates are high. Efficacy of medical treatment has increased with advances in targeted therapies, such as everolimus and sunitinib, and the introduction of radiolabeled somatostatin analogs. Several techniques for loco-regional control of metastases are available, including chemo- or radioembolization.

CONCLUSIONS

Treatment of patients with PNET metastases should be multidisciplinary and must be personalized according to the features of individual patients and tumors.

Con: Liver transplantation for expanded criteria malignant diseases

Organ shortage requires policies and guidelines to aid organ allocation along the principles of urgency or utility. Identifying patients with significant benefit and withholding liver transplantation (LT) from patients too sick for transplantation are ongoing challenges, in particular in patients with malignancies. An arbitrary threshold of >50% 5-year overall survival (OS) is broadly considered a minimum standard for LT. In patients transplanted for intrahepatic cholangiocarcinoma (iCC), this was only achieved in select cases and when the tumor had a diameter of <2 cm. In patients with extrahepatic and hilar cholangiocarcinoma (CCC), strict selection criteria and combined preoperative radiotherapy/chemotherapy according to the Mayo protocol showed that acceptable longterm results can be achieved in a single high-volume center but are difficult to repeat elsewhere. Furthermore, only rigorously selected patients with neuroendocrine tumors (NETs) meeting the NET Milan criteria adopted by United Network for Organ Sharing can also have >50% 5-year OS. A prospective study in patients with unresectable colorectal cancer metastases in the liver has shown promising OS rates, but further prospective trials are warranted. Current evidence shows that none of the proposed expanded malignant criteria justify deviation of scarce donor organs to patients with hilar CCC, iCC > 2 cm, metastatic NET beyond NET Milan criteria, or metastatic colorectal cancer (CRC) outside clinical trials. Liver Transplantation 24 104-111 2018 AASLD.

Liver transplantation for metastatic neuroendocrine tumors: Outcomes and prognostic variables

BACKGROUND

Patient selection for liver transplantation for metastatic neuroendocrine tumors remains a topic of debate. There is no established MELD exception, making it difficult to obtain donor organs.

METHODS

A multicenter database was created assessing outcomes for liver and multivisceral transplantation for metastatic neuroendocrine tumors and identifying prognostic factors for survival. Demographic, transplant, primary tumor site and management, pathology, recurrent disease and survival data were collected and analyzed. Survival probabilities were calculated using the Kaplan-Meier method.

RESULTS

Analysis included 85 patients who underwent liver transplantation November 1988-January 2012 at 28 centers. One, three, and five-year patient survival rates were 83%, 60%, and 52%, respectively; 40 of 85 patients died, with 20 of 40 deaths due to recurrent disease. In univariate analyses, the following were predictors of poor prognosis: large vessel invasion (P < 0.001), extent of extrahepatic resection at liver transplant (P = 0.007), and tumor differentiation (P = 0.003). In multivariable analysis, predictors of poor overall survival included large vessel invasion (P = 0.001), and extent of extrahepatic resection at liver transplant (P = 0.015).

CONCLUSION

In the absence of poor prognostic factors, metastatic neuroendocrine tumor is an acceptable indication for liver transplantation. Identification of favorable prognostic factors should allow assignment of a MELD exception similar to hepatocellular carcinoma.

Indication for liver transplantation in young patients with small intestinal NETs is rare?

BACKGROUND

A majority of patients with small intestinal neuroendocrine tumors (SI-NETs) present with or develop liver metastases (LM). A number of treatments for LM are used clinically, including liver transplantation (LTx). Indications for LTx are under debate; young age(<65 years), absence of extrahepatic disease, resected primary tumor and limited extent of LM have been suggested as inclusion criteria for LTx with the aim to optimize outcome.

MATERIALS AND METHODS

From our series of 672 patients with SI-NET treated at the University Hospital in Uppsala between 1985 and 2012, we identified 78 patients according to the following criteria: <65 years of age, locoregional surgery (LRS) of the primary tumor and mesenteric metastases successfully performed, LM present but no extrahepatic disease. Baseline was chosen as the first date the following points were met: First visit to our center,LRS performed, LM present. The patients underwent treatment according to the standard clinical protocols at our center, and during this time period we did not perform or refer any SI-NET patients for LTx. Kaplan-Meier survival analyses were performed in three different groups based on hypothetical criteria for LTx.

RESULTS

Five-year overall survival rates for patients <65 years (n = 78) and <55 years (n = 36) of age were 84 ± 8 and 92 ± 9 %, respectively. For patients fulfilling the Milan criteria (n = 33) the 5-year survival was 97 ± 6 %.

CONCLUSIONS

Most young patients (<65 years) with SINET and LM have a favorable survival with standardized multimodality treatment. Indeed, most survival figures reported after LTx of NET do not surpass these figures.

A multimodal approach to the management of neuroendocrine tumour liver metastases

Neuroendocrine tumours (NETs) are often indolent malignancies that commonly present with metastatic disease in the liver. Surgical, locoregional, and systemic treatment modalities are reviewed. A multidisciplinary approach to patient care is suggested to ensure all therapeutic options explored.

Liver transplantation for hepatic metastases of neuroendocrine pancreatic tumors: a survival-based analysis

BACKGROUND

Liver transplantation (LT) has been accepted as a treatment in selected cases of neuroendocrine tumors (NETs) with hepatic metastases.

PATIENTS AND METHODS

A systematic review of the literature was conducted to evaluate long-term patient survival in the instances of LT for pancreatic NET. Univariate and multivariate regression analyses and survival analysis were performed.

RESULTS

Fifty-three clinical studies were screened. Data from 20 studies encompassing 89 transplanted patients were included in the study. Most primary tumors were endocrine pancreatic tumors (n=69), with gastrinomas representing the most frequent diagnosis (n=21). There were 61 functioning pancreatic NET. Simultaneous LT and pancreatic NET resections were performed in 45 instances. Cumulative 1-, 3-, and 5-year survival was 71%, 55%, and 44%, respectively, with a calculated mean survival of 54.45±6.31 months. Vasoactive intestinal peptide (VIPomas) had the best overall survival. Recurrence-free survival at 1, 3, and 5 years was 84%, 47%, and 47%, respectively. Recipient age more than or equal to 55 years (P=0.0242) and simultaneous LT-pancreatic resection (P=0.0132) were found to be significant predictors of worse survival by both univariate and multivariate Cox proportional hazard analyses. A scoring system was developed, with prognostic points assigned as follows: age more than or equal to 55 years:age less than 55 years=1:0 points and simultaneous LT-pancreatic resection:LT alone=1:0 points. This stratification delineated three separate population samples corresponding to patients with scores of 0, 1, and 2, respectively. The calculated 5-year survival for scores 0, 1, and 2 was 61%, 40%, and 0%, respectively (P=0.0023).

CONCLUSIONS

Despite the limitations of this retrospective analysis, good results can be achieved even for pancreatic NET primaries if the above-proposed scoring system is applied.

Multimodal management of neuroendocrine liver metastases

BACKGROUND

The incidence of neuroendocrine tumours (NET) has increased over the past three decades. Hepatic metastases which occur in up to 75% of NET patients significantly worsen their prognosis. New imaging techniques with increasing sensitivity enabling tumour detection at an early stage have been developed. The treatment encompasses a panel of surgical and non-surgical modalities.

METHODS

This article reviews the published literature related to management of hepatic neuroendocrine metastases.

RESULTS

Abdominal computer tomography, magnetic resonance tomography and somatostatin receptor scintigraphy are widely accepted imaging modalities. Hepatic resection is the only potentially curative treatment. Liver transplantation is justified in highly selected patients. Liver-directed interventional techniques and locally ablative measures offer effective palliation. Promising novel therapeutic options offering targeted approaches are under evaluation.

CONCLUSIONS

The treatment of neuroendocrine liver metastases still needs to be standardized. Management in centres of expertise should be strongly encouraged in order to enable a multidisciplinary approach and personalized treatment. Development of molecular prognostic factors to select treatment according to patient risk should be attempted.

Liver transplantation for primary or secondary endocrine tumors

Endocrine tumors comprise a heterogeneous group of rare neoplasms. Liver metastatic endocrine tumors (MET) are amenable to various therapeutic modalities including liver transplantation (LT). However, LT for MET remains controversial because of the lack of clear selection criteria. The purpose of this study based on thorough perusal of English and French literature since 1989 was to identify prognostic factors and propose recommendations for selecting patients most likely to benefit LT for primary and secondary endocrine tumors.

Surgical management of liver metastases from gastrointestinal endocrine tumors

Liver metastases from endocrine tumors can reduce 5-year survival from 90% to 40% and, in cases of functional gastrointestinal endocrine tumors, lead to a carcinoid syndrome. Complete resection of cancerous disease should be considered in all cases. Indeed, after hepatectomy, prolonged survival (41-86% at five years) can be achieved, with low rates of surgery-related mortality (0-6.7%). Extended liver resection is required in most cases. Percutaneous portal embolization increases the volumetric feasibility of resection, and sequential hepatectomy techniques enable a two-stage resection of both bilobar metastases and the primary tumor. For carcinoid syndrome that does not respond to medical therapy, incomplete resection of liver metastases, by reducing tumor volume, may be indicated to reduce symptoms and halt the progression of carcinoid heart disease. In cases of non-resectable liver metastases in selected patients, liver transplantation can lead to 5-year survival rates as high as 77%.

Liver transplantation and pancreatic resection: a single-center experience and a review of the literature

Liver transplantation may occasionally be indicated in patients with unique clinical scenarios. Little is known regarding the outcomes of patients who have had a pancreatic resection prior to, in combination with, or after liver transplantation. A retrospective review of all patients undergoing liver transplantation from March 1998 to March 2008 identified 17 patients who also underwent pancreatic resection. An additional literature review was performed. Five underwent pancreatic resection prior to liver transplantation (1.7, 3.6, 3.8, 6.8, and 8.1 years), another 9 underwent pancreatic resection together with liver transplantation, and 3 underwent pancreatic resection after liver transplantation (2.2, 2.6, and 3.8 years). Indications for pancreatic resection included cholangiocarcinoma (n = 6), neuroendocrine tumor (n = 5), pancreatic cancer (n = 2), gastrointestinal stromal tumor (n = 1), periampullary adenocarcinoma (n = 1), duodenal adenomas (n = 1), and benign pancreatic mass (n = 1). Indications for liver transplantation were metastatic neuroendocrine tumor disease (n = 5), primary sclerosing cholangitis (n = 5), hepatitis C virus (n = 2), metastatic gastrointestinal stromal tumor (n = 1), Klatskin tumor (n = 1), alcohol cirrhosis (n = 1), alpha-1 antitrypsin deficiency (n = 1), and chemotherapy-induced cirrhosis (n = 1). One patient died intraoperatively, 7 patients died of tumor recurrence, 2 patients died from transplant complications, and 7 patients are still alive. Pancreatic resection-related complications included 4 pancreatic fistulas. A literature review confirmed liver transplantation/pancreatic resection-related complications. In conclusion, liver transplantation and pancreatic resection remain uncommon, and a good outcome can be achieved. Recurrence of malignant disease is the main factor limiting survival, and specific morbidity may be related to pancreatic resection and liver transplantation.

[Indications and operative procedures for neuroendocrine liver metastases]

Neuroendocrine malignancies encompass a variety of tumors that differ considerably in origin, hormonal activity, and biological behavior. Because of their rarity most therapeutic recommendations have been based on limited evidence from small retrospective series observing miscellaneous patient cohorts. Only in recent years proposals for TNM and histological grading systems have been elaborated that allow further stratification of patients suffering from these tumors. Especially patients with well and moderately differentiated neuroendocrine malignancies benefit from resection of liver metastases, improving the 5-year survival rate from <50% to 80%. Orthotopic liver transplantation can likewise improve survival in carefully selected patients. New developments in imaging modalities, intensive care treatment, and in liver surgery itself have broadened the selection of potentially resectable tumors.

Treatment of endocrine pancreatic tumors

Endocrine pancreatic tumors are rare with an incidence of 4 per million inhabitants. Most tumors are malignant except for insulinomas that usually are benign. They are slowly growing in the majority of cases but there are exceptions with rapidly progressing malignant carcinomas. Because of the rarity of these tumors large randomized trials are difficult to accomplish. However, most physicians treating these patients agree that surgery should be considered in all cases and that medical treatment with chemotherapy and biotherapy is well established for this group of patients.

Liver transplantation for metastatic neuroendocrine tumor: a case report and review of the literature

Neuroendocrine tumors are divided into gastrointestinal carcinoids and pancreatic neuroendocrine tumors. The WHO has updated the classification of these lesions and has abandoned the term "carcinoid". Both types of tumors are divided into functional and non-functional tumors. They are characterized by slow growth and frequent metastasis to the liver and may be limited to the liver for long periods. The therapeutic approach to hepatic metastases should consider the number and distribution of the liver metastases as well as the severity of symptoms related to hormone production and tumor bulk. Surgery is generally considered as the first line therapy. In patients with unresectable liver metastases, alternative treatments are dependent on the type and the growth rate. Initial treatments consist of long acting somatostatin analogs and/or interferon. Streptozocin-based chemotherapy is usually reserved for symptomatic patients with rapidly advancing disease, but generally the therapy is poorly tolerated and its effects are short-lived. Locoregional therapy directed such as hepatic-artery embolization and chemoembolization, radiofrequency thermal ablation and cryosurgery, is often used instead of systemic therapy, if the disease is limited to the liver. However, liver transplantation should be considered in patients with neuroendocrine metastases to the liver that are not accessible to curative or cytoreductive surgery and if medical or locoregional treatment has failed and if there are life threatening hormonal symptoms. We report a case of liver transplantation for metastatic neuroendocrine tumor of unknown primary source and provide a detailed review of the world literature on this controversial topic.

[Surgical treatment of gastric, enteric pancreatic endocrine tumors. Part 2. treatment of hepatic metastases]

The development of hepatic metastases (HM) marks a turning point in the evolutionand prognosis of well-differentiated endocrine tumors (ET). Management is usually multicisciplinary (chemotherapy, arterial chemo-embolization, percutaneous ablation, somatostatin analogs, biotherapy, and surgery). A thorough pre-operative work-up is neecessary to exclude extrahepatic disease and to detect tiny HM's. Complete resection (RO) is the only curative treatment for well-differentiated ET with HM. The type of resection is specific to each case and may range from wedge resection of a metastasis to complex hepatectomy with simultaneous resection of the primary ET. Cytoreductive surgery may be indicated for palliation when medical therapy fails to control endocrine symptoms. Operative mortality is low (0-6%) and global survival is 60-70% afterafter R) resection of HM of well-differentiated ET's. After resection of HM involving only one hepatic lobe, 5 year survival is better than 90%. When HM are multiple, bilobar and synchronous, the prognosis is very poor--only 10% of such patients can have a complete resection and this often requires a long prologue of ancillary procedures (chemotherapy, chemoembolization, portal vein ligation, percutaneous ablation). Hepatic transplantation (HT) has only a limited rôle in the treatment of HM for ET; mortality is high when HT is associated with large and complex resections, i.e. pancreaticoduodenectomy. Although there is no consensus in the literature, HT should be limited to the most optimal cases (young, good general health, well-differentiated tumor, slow evolution, complete resection of the primary rumor, and unresectable liver metastases). Global survival for HT in patients with ET is 60% at 2 years, 47% at 5 years; tumor-free survival at 5 years is 24%. HT for HM has better survival results for ET's of intestinal origin (carcinoids) than for duodenopancreatic ET's.

Carcinoids of the pancreas

BACKGROUND

The aim of the current study was to clarify the actual clinicopathologic status of extremely rare pancreatic carcinoids. To date, statistical evaluation of such carcinoids has been hampered because an insufficient number of cases has prevented any reliable statistical analyses.

METHODS

The Niigata Registry for Gut-Pancreatic Endocrinomas contains a total number of 156 cases of pancreatic carcinoids among 165 endocrinocarcinomas registered worldwide. This figure of 156 cases comprises 144 typical and 12 atypical carcinoids, which were compared statistically with carcinoids in other representative sites, according to various clinicopathologic criteria.

RESULTS

Pancreatic carcinoids made up 1.4% of the total number of registered cases (n = 11,343) and were characteristic in the following five ways. 1) They exhibited a high metastatic rate (66.7%), somewhat lower than that for the ileocecum (76.1%), identical to that for the ileum (66.9%), and far higher than that for the total average of 35.7%. 2) They displayed the largest average tumor size (68.6 mm), followed by that for the ovary (68.2 mm), and ileocecum (46.5 mm) against a total average of 30.2 mm. 3) They revealed a relatively high incidence of the carcinoid syndrome (23.3%), almost equal to that for the ileocecum (24.1%), and exceeded by that for the small intestine (35.8%), when compared with that for the total average of 11.0%. 4) They showed a high rate of immunohistochemical detection for serotonin (92.9%), lower than that for the testicle (100.0%), but higher than the total average of 54.9%. 5) Five-year survival rate was extremely low (28.9% +/- 16.7%) compared with those for the appendix (89.7% +/- 2.0%) and the small intestine (82.1% +/- 3.3%). It was noteworthy that silver impregnations in the pancreatic carcinoid series indicated a result identical to that for the total average: Grimelius argyrophilia, 84.8% versus 85.4%; argyrophil cell type, 59.1% versus 58.5%; and argentaffin cell type, 22.7% versus 22.3%.

CONCLUSION

It may be said that in the treatment of patients with pancreatic carcinoids, appropriate procedures should be carried out with these distinguishing characteristics always kept in mind.

Chemotherapy for gastro-enteropancreatic endocrine tumours

Despite similar histological and morphological aspects, gastro-enteropancreatic (GEP) endocrine tumours represent a heterogeneous group of tumours with varying clinical expression depending on tumour type (functional or not), origin and extension, but also on histological differentiation and proliferative capacity. The natural history of well-differentiated tumours is often favourable without treatment and GEP endocrine tumours may remain indolent for many years. Chemotherapy may however be indicated in the presence of symptomatic non-progressive disease (progression evaluated over 3-6 months). In contrast, poorly differentiated GEP endocrine tumours are frequently aggressive and early treatment is required. Accurate staging is mandatory and where surgery is possible (even in the event of limited metastatic disease), this option should be re-evaluated in a multidisciplinary approach. Approximately 2/3 of malignant GEP tumours are metastatic at discovery and surgery is possible in a minority of patients; therefore, chemotherapy, with/without other strategies (e.g. local ablation), is frequently indicated in patients with symptomatic, bulky or progressive disease. For well-differentiated pancreatic tumours, the reference association is Adriamycin with streptozotocin yielding objective responses (OR) in 40-60% of patients. Prolonged treatment is limited due to potential cardiotoxicity of Adriamycin and standard 2nd-line regimens are not of proven efficacy; thus, other treatment modalities are usually additionally required (e.g. chemo-embolisation). A significant OR may render a small number of patients secondarily amenable to surgery. Published series evaluating chemotherapy for midgut endocrine tumours are outdated and disappointing. Objective response rates with combined associations (including either 5-fluorouracil and/or streptozotocin) rarely exceed 20% and where possible, chemo-embolisation for hepatic metastases combined with somatostatin analogues (+/- interferon) should be preferred. Poorly differentiated GEP tumours are generally aggressive tumours with metastases at diagnosis and tend to progress rapidly. Surgery is rarely possible and ineffective even in locally advanced disease due to a high risk of recurrence. Chemotherapy, using cisplatin and etoposide, is the reference treatment and frequently yields OR rates >50%. However, despite being chemosensitive, disease control is limited (8-10 months). Overall, advances in therapeutic chemotherapeutic options are required in the management of all types of advanced GEP endocrine tumours and evaluation of new drugs (e.g. irinotecan) and combination strategies (chemotherapy with local ablative therapies) are required in the future.