Analysis of recurrence after resection of well-differentiated non-functioning pancreatic neuroendocrine tumors

Abstract

Although pancreatic neuroendocrine tumors (PNETs) are generally considered to have a favorable overall prognosis after resection, disease recurrence has been observed. Few studies have specifically addressed recurrence after resection of PNETs, especially for non-functioning PNETs (NF-PNETs). The aim of our study is to analyze the recurrence of resected well-differentiated NF-PNETs. Patients who underwent surgical resection for grade 1 and 2 NF-PNETs without synchronous metastasis were identified for analysis. Patients were treated from January 2009 to December 2017 in our institution. Univariate and multivariate cox regression analysis were conducted to identify prognostic factors. Of the 88 patients, 46 were men (52%) and the mean age was 52 years. With a median follow-up of 49.1 months (range, 8–122 months), there were 12 recurrences (14%). Liver was the most common recurrence site (7/12, 58%). The 1-, 3-, and 5-year recurrence-free survival was 99%, 90%, and 88%, respectively. Univariate analysis identified that age >52 years, positive lymph nodes, tumor grade 2, and Ki67 index ≥5% were statistically significant. Multivariate analysis identified that Ki67 index ≥5% (hazard ratio [HR], 4.69; 95% confidence interval [CI], 1.36–16.75, P = .015), positive lymph nodes (HR, 6.75; 95% CI, 1.73–24.43, P = .006) were independently associated with recurrence. The 5-year disease-free survival rate was 53% (95% CI, 14.20–91.81%) for patients with Ki-67 ≥5% or (and) positive lymph nodes, while 95% (95% CI, 82.26–100%) for the patients without these 2 factors. Ki67 index and lymph node status are independently associated with recurrence after resection of well-differentiated NF-PNETs in this study.

Prognosis analysis of patients with pancreatic neuroendocrine tumors after surgical resection and the application of enucleation

“…Among patients who had received surgical resection, the long-term prognosis between blacks and whites were not significant difference in this study, and white people had worse OS/CSS than that of other race such as Asian American. Many studies suggested that preoperative lymph node metastasis was associated with the long-term prognosis in pNET patients [ 18 , 19 ], while others have not found a significant connection [ 20 , 21 ]. In this study, Cox multivariate analysis suggested that lymph node metastasis could not be used as an independent prognostic factor for postoperative patients.…”

Prognostic factors of non-functioning pancreatic neuroendocrine neoplasms after curative surgery and risk factors for liver recurrence

“…Several factors for poor prognosis, including pathological tumour size, margin status, tumour grade, Ki-67 index, perineural invasion, microvascular invasion, and LNM, have been previously reported in patients with NF-PNENs after curative surgery [7][8][9][10][11]13]. However, in this study, multivariate analysis showed that only the presence of LNM was independently associated with poor OS and DFS in patients with NF-PNENs.…”

“…Several previous studies have also reported that LNM is independently associated with poor prognosis in patients with PNENs [12,13,18]. Tan et al investigated the predictors of recurrence in 88 patients with well-differentiated NF-PNENs after curative surgery and found that the presence of LNM was most strongly associated with recurrence, and patients with LNM developed recurrence seven times more often than those without it [13]. In addition, Fischer et al investigated the predictors of poor OS in 291 patients with PNENs after surgical resection [18].…”

“…According to previous reports, the liver is the most frequent site of recurrence of NF-PNENs [13][14][15][16]. However, no reports have investigated the risk factors for liver recurrence in NF-PNENs.…”

Prognosis Analysis of Patients with Pancreatic Neuroendocrine Tumors After Surgical Resection and the Application of Enucleation.

“…Among patients who had received surgical resection, the long-term prognosis between blacks and whites were not signi cant difference in this study, and white people had worse OS/CSS than that of other race such as Asian American. Many studies suggested that preoperative lymph node metastasis is associated with the long-term prognosis in pNET patients [19,20], while others have not found a signi cant connection [21,22]. In this study, Cox multivariate analysis suggested that lymph node metastasis could not be used as an independent prognostic factor for postoperative patients.…”