Survey of surgical resections for neuroendocrine liver metastases: A project study of the Japan Neuroendocrine Tumor Society (JNETS)

Abstract

Background/Purpose Hepatic resection is considered the treatment of choice for neuroendocrine liver metastases (NELM). However, the safety and efficacy of resection have not been fully evaluated using a large cohort. The aim of the present study was to collect real‐world data regarding hepatic resections for NELM. Methods A retrospective, multicenter survey was conducted. The background characteristics of patients undergoing an initial hepatic resection for NELM, the operative details, pathological findings, and patient outcomes were investigated. Results A total of 222 patients were enrolled from 30 institutions. The primary tumor site was the pancreas in 58.6%, and the presentation of NELM was synchronous in 63.1% of the cases. Concomitant resection of the primary tumor and liver metastases was performed for 66.4% of the synchronous metastases, and the 90‐day morbidity and mortality rates were 12.6% and 0.9%, respectively. The operations resulted in R2 resections in 26.1% of the cases, and 83.4% of the patients experienced recurrence after R0/1 resections. However, the patients were treated using multiple modalities after R2 resection or recurrence, and the overall survival rate was relatively favorable, with 5‐year and 10‐year survival rates of 70.2%, and 43.4%, respectively. Univariable and multivariable analyses identified the tumor grading (G3) of the primary tumor as a significant prognostic factor for both the recurrence‐free and overall survivals. Conclusions The present data confirmed the safety of the surgical resection of NELM. Although recurrences were frequent, the survival outcomes after resection were favorable when a multi‐disciplinary treatment approach was used.

Chinese expert consensus on multidisciplinary diagnosis and treatment of pancreatic neuroendocrine liver metastases

“…The analysis of a study by the Japanese NET Society (JNETS) found that, after R0/1 resection of pNETs liver metastases, the recurrence rate of intrahepatic metastases was 63.4%. [109] Despite the high postoperative recurrence rate, a few studies have reported on its postoperative treatment.…”

Surgery for metastatic pancreatic neuroendocrine tumors: a narrative review

“…Ultimately, however, various reviews have linked NELMs resection to an improvement in symptoms and longer OS for patients with PanNETs, but this has not yielded a consensus on its overall benefits given the presence of selection bias, lack of randomized trials, and availability of other management options. Table 4 below summarizes the findings of several articles relating to resection of NELM (31)(32)(33)(34)(35)(36)(38)(39)(40)(41)(42).…”

“…One consistency throughout most studies covering surgical resection for NELMs is the high rate of metastatic recurrence observed. In their pancreatic NELMs specific review, Partelli et al document a recurrence rate of 76.5% after surgical resection while a recent multi-institutional study from Japan noted only a 13.4% 5-year recurrence-free survival rate in their surgically treated patients, 59% of which had PanNET primaries ( 34 , 38 ).…”

“…The authors postulated that hepatic abscess formation may be limited by performing ablations or resections of hepatic parenchyma prior to introducing the potential for bacterial contamination from the biliary-enteric anastomosis of the pancreaticoduodenectomy. A multi-institutional neuroendocrine review from Japan included large numbers of concomitant pancreas and NELMs resections, including 16 pancreaticoduodenectomies, with reportedly acceptable 12–13% 90-day morbidity rates ( 38 ). The recent NANETS guidelines reiterated the safe outcomes demonstrated with simultaneous pancreatic tumor and NELMs resection and remarked that resection of pancreatic head tumors should be avoided prior to NELMs directed therapy given the concern for hepatic abscess development ( 6 ).…”

Parenchyma-Sparing Liver Resection or Regenerative Liver Surgery: Which Way to Go?

“…In the case of NELM, LR is the treatment of choice whenever feasible, since patient outcomes after resection have been reported to be favorable compared to those with unresectable tumors [ 120 ]. Repeat hepatectomy, if feasible, can be a good option for intra-hepatic recurrence and can provide long-term survival [ 121 ].…”