Long term survival analysis of hepatectomy for neuroendocrine tumour liver metastases

Surgery, Liver Directed Therapy and Peptide Receptor Radionuclide Therapy for Pancreatic Neuroendocrine Tumor Liver Metastases

Pancreatic neuroendocrine tumors (PNETs) are described by the World Health Organization (WHO) classification by grade (1–3) and degree of differentiation. Grade 1 and 2; well differentiated PNETs are often characterized as relatively “indolent” tumors for which locoregional therapies have been shown to be effective for palliation of symptom control and prolongation of survival even in the setting of advanced disease. The treatment of liver metastases includes surgical and non-surgical modalities with varying degrees of invasiveness; efficacy; and risk. Most of these modalities have not been prospectively compared. This paper reviews literature that has been published on treatment of pancreatic neuroendocrine liver metastases using surgery; liver directed embolization and peptide receptor radionuclide therapy (PRRT). Surgery is associated with the longest survival in patients with resectable disease burden. Liver-directed (hepatic artery) therapies can sometimes convert patients with borderline disease into candidates for surgery. Among the three embolization modalities; the preponderance of data suggests chemoembolization offers superior radiographic response compared to bland embolization and radioembolization; but all have similar survival. PRRT was initially approved as salvage therapy in patients with advanced disease that was not amenable to resection or embolization; though the role of PRRT is evolving rapidly

Integrative Concepts for Liver Surgery

BACKGROUND

Surgery is the standard treatment for primary tumors and metastases. Due to improvements in surgical outcomes as well as the efficacy of systemic treatments, the role of surgery has changed in recent years.

SUMMARY

Liver surgery has become safe and efficient, with resectability being increased by multimodality concepts as well as staged liver resections and orthotopic liver transplantation. These concepts may be applied to primary liver tumors but also to selected patients with liver metastases from various diseases. In addition, even debulking surgery may be indicated for selected patients with endocrine metastases. While patient selection for liver resections was limited to clinical parameters in the past, histological and molecular characteristics have become increasingly important. Moreover, the response to regional or systemic chemotherapy has been demonstrated to be strong for a beneficial course of the disease even in advanced diseases.

KEY-MESSAGES

Due to the variety of available treatment options, optimal patient selection is crucial. Besides liver surgery, staged concepts as well as liver transplantation are curative tools for many patients.

Comparative analysis of colorectal mixed adenoneuroendocrine carcinoma and adenocarcinoma with neuroendocrine differentiation: a population-based study

BACKGROUND

Colorectal mixed adenoneuroendocrine carcinoma (MANEC) and adenocarcinoma with neuroendocrine differentiation (ANED) are recognized as different tumors pathologically and clinically. In a population-based study, the clinicopathologic characteristics and treatment strategies of the two tumors were comparatively analyzed.

METHODS

Patients with colorectal adenocarcinoma (ADEC), neuroendocrine carcinoma (NEC), MANEC and ANED were identified diagnosis from 2010 to 2014 using the Surveillance, Epidemiology, and End Results (SEER) database. The clinicopathologic data were analyzed by Chi-square test, univariable and multivariable Cox regression. Nomogram was performed to provide a prognostic evaluation for colorectal MANEC and ANED.

RESULTS

Totally 82121 patients were recruited in this cohort. There was no difference between MANEC and ANED in clinicopathologic characteristics and prognosis (P>0.05). The survival data showed that 1-year and 3-year survival rates were 84.70% and 67.83% for ADEC, 66.83% and 51.98% for NEC, and 54.27% and 37.68% for MANEC and ANED, respectively. Stage and surgery were independent prognostic factors of colorectal MANEC/ANED. We also found that the prognosis was significantly different without vs with chemotherapy (P=0.000) in stage III colorectal MANEC/ANED; without vs with surgery (P=0.007), and without vs with chemotherapy (P=0.000) in stage IV colorectal MANEC/ANED. Radiation did nothing for improving the prognosis of colorectal MANEC/ANED in stage III and stage IV (P=0.557, 0.677).

CONCLUSIONS

MANEC and ANED should be merged into the same category pathologically and clinically, and had the poorest prognosis. Stage and surgery were independent prognostic risk factors for colorectal MANEC/ANED. The prognosis of MANEC/ANED could not benefit from radiation.

Gastroenteropancreatic Neuroendocrine Tumors with Liver Metastases in Korea: A Clinicopathological Analysis of 72 Cases in a Single Institute

Purpose

Management of gastroenteropancreatic (GEP) neuroendocrine tumors with liver metastases (NETLM) presents many clinical challenges. Assessment of the extent of disease and primary tumor site is crucial for management. In this study, we investigated the primary tumor sites and prognostic factors in GEP NETLM among Korean patients.

Materials and Methods

We reviewed the medical records of 72 Korean patients diagnosed with GEP NETLM between January 1999 and May 2013, focusing on their clinical and pathologic characteristics.

Results

The most frequently encountered primary tumor sites were the pancreas (n=25, 35%), stomach (n=8, 11%), gall bladder (n=4, 6%) and rectum (n=3, 4%). Twenty-five patients (35%) had occult primary tumor. Twelve patients (17%) had histological grade G1 tumors, 30 patients (42%) had G2 tumors, and 30 patients (42%) had G3 tumors. The mean follow-up period after histological confirmation of hepatic metastases was 11.30±2.44 months for G3 tumors, 19.67±4.09 months for G2 tumors, and 30.67±6.51 months for G1 tumors. Multivariate analyses revealed that an unknown primary tumor site (p=0.001) and higher histological grade (p < 0.001) were independent prognostic indicators for shorter overall survival (OS). Most long-term survivors (OS > 24 months) had received antitumor treatment.

Conclusion

The primary tumor site most frequently associated with GEP NETLM was the pancreas. Unknown primary tumor and higher histological grade were independent prognostic indicators for shorter OS. Patients identified as being at a risk of shorter OS should be followed up closely.

Surgical therapy of neuroendocrine neoplasm with hepatic metastasis: patient selection and prognosis

BACKGROUND

Patients with neuroendocrine neoplasms (NEN) develop hepatic metastases in 50-95 %. The aims of this study were to evaluate the outcome/prognosis of patients following hepatic surgery and to identify predictive factors for the selection of patient that benefit from hepatic tumor resection.

PATIENTS AND METHODS

In a retrospective single-center study (1990 to 2014), 204 patients with hepatic metastasis of NEN were included. Ninety-four were subjected to various forms of liver resection. According to the overall survival, the influence of several prognostic factors like the Ki-67 index, stage of disease, and resection status was evaluated.

RESULTS

The primary tumor was located in the small intestine (n = 73), pancreas (n = 58), colon (n = 26), esophagus or stomach (n = 9) and in 38 patients the primary site was unknown. The Ki-67 index was associated with significant different overall survival. Patients with an R0 resection (n = 38) of their hepatic metastasis had a very good 10-year survival of 90.4 %. Patients in whom an R1 (n = 23) or R2 (n = 33) resection of their hepatic metastasis could be achieved had a 10-year survival of 53.4 and 51.4 %, respectively. The majority of the patients (53.9 %) could not be resected and had a poor 10-year survival rate of 19.4 %. Partial or complete control of endocrine-related symptoms was achieved in all patients with functioning tumors following surgery. The overall 5- and 10-year survival rates were 77.9 and 65.2 %, respectively.

CONCLUSION

Surgical resection of hepatic NEN metastases can reduce symptoms and improve the survival in selected patients with a Ki-67 index less than 20 %. The expected outcome has to be compared to the outcome of alternative treatment strategies. An R0 situation should be the aim of hepatic surgery, but also patients with R1 or R2 resection show a good survival benefit.

Solitary hypervascular liver metastasis from neuroendocrine tumor mimicking hepatocellular cancer: All that glitters is not gold

Neuroendocrine tumor metastases to the liver can mimic primary hepatocellular carcinoma (HCC) on imaging, cytology, and core biopsy. We present a case study along with the literature review of a patient who presented as a solitary liver mass mimicking HCC and subsequently underwent a partial hepatectomy. The histopathology and immunohistochemisrty of the resected specimen revealed metastatic neuroendocrine carcinoma. Positron emission tomography (PET) scan with ⁶⁸Ga-DOTA-NaI-octreotide (⁶⁸Ga-DOTANOC) localized the primary tumor in the ileum. A curative follow-up surgery for resection of the small bowel containing the primary tumor was carried out. This case illustrates the shortcomings of routine imaging methods, utility of immunocytochemistry and the importance of ⁶⁸Ga-DOTANOC PET in determining the metastatic spread as well as the origin of neuroendocrine tumors (NETs). This case report attempts to highlight the current imaging paradigms and management strategy of midgut and other NET's at the point of detection, staging and follow-up.