Accuracy and Prognostic Impact of Nodal Status on Preoperative Imaging for Management of Pancreatic Neuroendocrine Tumors: A Multi-Institutional Study

BACKGROUND

We sought to define the accuracy of preoperative imaging to detect lymph node metastasis (LNM) among patients with pancreatic neuroendocrine tumors (pNETs), as well as characterize the impact of preoperative imaging nodal status on survival.

METHODS

Patients who underwent curative-intent resection for pNETs between 2000 and 2020 were identified from eight centers. Sensitivity and specificity of computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET)-CT, and OctreoScan for LNM were evaluated. The impact of preoperative lymph node status on lymphadenectomy (LND), as well as overall and recurrence-free survival was defined.

RESULTS

Among 852 patients, 235 (27.6%) individuals had LNM on final histologic examination (hN1). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 12.4%, 98.1%, 71.8%, and 74.4% for CT, 6.3%, 100%, 100%, and 80.1% for MRI, 9.5%, 100%, 100%, and 58.7% for PET, 11.3%, 97.5%, 66.7%, and 70.8% for OctreoScan, respectively. Among patients with any combination of these imaging modalities, overall sensitivity, specificity, PPV, and NPV was 14.9%, 97.9%, 72.9%, and 75.1%, respectively. Preoperative N1 on imaging (iN1) was associated with a higher number of LND (iN1 13 vs. iN0 9, p = 0.003) and a higher frequency of final hN1 versus preoperative iN0 (iN1 72.9% vs. iN0 24.9%, p < 0.001). Preoperative iN1 was associated with a higher risk of recurrence versus preoperative iN0 (median recurrence-free survival, iN1→hN1 47.5 vs. iN0→hN1 92.7 months, p = 0.05).

CONCLUSIONS

Only 4% of patients with LNM on final pathologic examine had preoperative imaging that was suspicious for LNM. Traditional imaging modalities had low sensitivity to determine nodal status among patients with pNETs.

Low Prognostic Nutritional Index Is Common and Associated with Poor Outcomes following Curative-Intent Resection for Gastro-Entero-Pancreatic Neuroendocrine Tumors

INTRODUCTION

To investigate the impact of prognostic nutritional index (PNI) on short- and long-term outcomes of patients who underwent curative-intent resection for gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs).

METHODS

Patients with GET-NETs who underwent curative-intent resection were identified from a multi-center database. The prognostic impact of clinicopathological factors including PNI on post-operative outcomes were evaluated. A novel nomogram was developed and externally validated.

RESULTS

A total of 2,099 patients with GEP-NETs were included in the training cohort; 255 patients were in the external validation cohort. Median PNI (n = 973) was 47.4 (IQR 43.1-52.4). At the time of presentation, 1,299 (61.9%) patients presented with some type of clinical symptom. Low-PNI (≤42.2) was associated with gastrointestinal symptoms, as well as nodal metastasis and distant metastasis (all p < 0.05). Patients with a low PNI had a higher incidence of severe (≥Clavien-Dindo grade IIIa: low PNI 24.9% vs. high PNI 15.4%, p = 0.001) and multiple (≥3 types of complications: low PNI 14.5% vs. high PNI 9.2%, p = 0.024) complications, as well as a worse overall survival (OS)(5-year OS, low PNI 73.7% vs. high PNI 88.5%, p < 0.001), and RFS (5-year RFS, low PNI 68.5% vs. high PNI 79.8%, p = 0.008) versus patients with high PNI (>42.2). A nomogram based on PNI, tumor grade and metastatic disease demonstrated excellent discrimination and calibration to predict OS in both the training (C-index 0.748) and two external validation (C-index 0.827, 0.745) cohorts.

CONCLUSIONS

Low PNI was common and associated with worse short- and long-term outcomes among patients with GEP-NETs.

Prognostic implication of the neoadjuvant rectal score and other biomarkers of clinical outcome in Hong Kong Chinese patients with locally advanced rectal cancer undergoing neoadjuvant chemoradiotherapy

BACKGROUND

Neoadjuvant chemoradiotherapy is a standard treatment for locally advanced rectal cancer, for which pathological complete response is typically used as a surrogate survival endpoint. Neoadjuvant rectal score is a new biomarker that has been shown to correlate with survival. The main objectives of this study were to investigate factors contributing to pathological complete response, to validate the prognostic significance of neoadjuvant rectal score, and to investigate factors associated with a lower neoadjuvant rectal score in a cohort of Hong Kong Chinese.

METHODS

Data of patients with locally advanced rectal cancer who received neoadjuvant chemoradiotherapy from August 2006 to October 2018 were retrieved from hospital records and retrospectively analysed.

RESULTS

Of 193 patients who had optimal response to neoadjuvant chemoradiotherapy and surgery, tumour down-staging was the only independent prognostic factor that predicted pathological complete response (P<0.0001). Neoadjuvant rectal score was associated with overall survival (hazard ratio [HR]=1.042, 95% confidence interval [CI]=1.021-1.064; P<0.0001), disease-free survival (HR=1.042, 95% CI=1.022-1.062; P<0.0001), locoregional recurrence-free survival (HR=1.070, 95% CI=1.039-1.102; P<0.0001) and distant recurrence-free survival (HR=1.034, 95% CI=1.012-1.056; P=0.002). Patients who had pathological complete response were associated with a lower neoadjuvant rectal score (P<0.0001), but pathological complete response was not associated with survival. For patients with intermediate neoadjuvant rectal scores, late recurrences beyond 72 months from diagnosis were observed.

CONCLUSION

Neoadjuvant rectal score is an independent prognostic marker of survival and disease recurrence in a cohort of Hong Kong Chinese patients who received neoadjuvant chemoradiotherapy for locally advanced rectal cancer.

Surgical Treatment of Neuroendocrine Tumors of the Terminal Ileum or Cecum: Ileocecectomy Versus Right Hemicolectomy

BACKGROUND

Simple ileocecectomy and right hemicolectomy are two potential operative approaches to treat patients with neuroendocrine neoplasm in the terminal ileum and/or cecum (IC-NENs). We sought to define the long-term outcome of patients undergoing ileocecectomy versus right hemicolectomy for IC-NENs, as well as characterize number of nodes evaluated and lymph node metastasis (LNM) associated with each procedure.

METHODS

Patients who underwent curative-intent resections for IC-NENs between 2000 and 2016 were identified from a multi-institutional database. The clinicopathologic characteristics, surgical procedures, and the overall (OS) and recurrence-free survival (RFS) were compared among patients who underwent formal right hemicolectomy versus ileocecectomy only.

RESULTS

Among 127 patients with IC-NENs, median size of the largest tumor size was 2.0 (IQR 1.2-2.9) cm; 35 (27.6%) patients had multiple lesions. At the time of surgery, 93 (73.2%) patients underwent a right hemicolectomy, whereas 34 (26.8%) had ileocecectomy only. Every patient had a lymph node dissection (LND) with a median number of 16 (IQR 12-22) nodes evaluated. A majority (n = 110, 86.6%) of patients had LNM with a median number of 3 (IQR 2-5) LNM. Patients who underwent hemicolectomy had more lymph nodes evaluated versus patients who had an ileocecectomy only (median, 18 vs. 14, p = 0.004). Patients who underwent formal right hemicolectomy versus ileocecectomy had a similar OS (median OS, 101.9 vs. 144.5 months, p = 0.44) and RFS (median RFS, 70.3 vs. not attained, p = 0.80), respectively.

CONCLUSIONS

Ileocecectomy had similar long-term outcomes versus right hemicolectomy in treatment of IC-NENs despite a difference in the lymph node harvest.

Development and Validation of a Modified Eighth AJCC Staging System for Primary Pancreatic Neuroendocrine Tumors

OBJECTIVE

To improve the prognostic accuracy of the eighth edition of AJCC staging system for pNETs with establishment and validation of a new staging system.

BACKGROUND

Validation of the updated eighth AJCC staging system for pNETs has been limited and controversial.

METHODS

Data from the SEER registry (1975-2016) (n = 3303) and a multi-institutional database (2000-2016) (n = 825) was used as development and validation cohorts, respectively. A mTNM was proposed by maintaining the eighth AJCC T and M definitions, and the recently proposed N status as N0 (no LNM), N1 (1-3 LNM), and N2 (≥4 LNM), but adopting a new stage classification.

RESULTS

The eighth TNM staging system failed to stratify patients with stage I versus IIA, stage IIB versus IIIA, and overall stage I versus II relative to long-term OS in both database. There was a monotonic decrement in survival based on the proposed mTNM staging classification among patients derived from both the SEER (5-year OS, stage I 87.0% vs stage II 80.3% vs stage III 72.9% vs stage IV 57.2%, all P < 0.001), and multi-institutional (5-year OS, stage I 97.6% vs stage II 82.7% vs stage III 78.4% vs stage IV 50.0%, all P < 0.05) datasets. On multivariable analysis, mTNM staging remained strongly associated with prognosis, as the hazard of death incrementally increased with each stage among patients in the 2 cohorts.

CONCLUSION

A mTNM pNETs clinical staging system using N0, N1, N2 nodal categories was better at stratifying patients relative to long-term OS than the eighth AJCC staging.

Surgical outcomes of gastro-entero-pancreatic neuroendocrine tumors G3 versus neuroendocrine carcinoma

BACKGROUND

To define surgical outcomes of patients with high-grade gastro-entero-pancreatic neuroendocrine neoplasm grade G3 (GEP-NEN G3).

METHODS

Patients who underwent surgical resection between 2000 and 2016 were identified. The overall survival (OS) and recurrence-free survival (RFS) of patients with gastro-entero-pancreatic neuroendocrine tumors grade G3 (GEP-NET G3) versus neuroendocrine carcinoma (NEC) were evaluated.

RESULTS

Fifty-one out of 2182 (2.3%) patients who underwent surgical resection were diagnosed as GEP-NEN G3. The pancreas was the most common primary site (n = 3772.5%). A majority of patients had lymph node metastasis (n = 3262.7%); one in three (n = 1631.4%) had distant metastasis. The median OS and RFS of the entire cohort were 56.4 and 34.5 months, respectively. Perineural invasion was a strong prognostic factor associate with OS after surgical resection. Patients with NEC had a worse survival outcome versus patients with NET G3 (median OS: 33.1 months vs. not attained, p = 0.088). In contrast, among patients who underwent curative-intent resection, patients with NEC had comparable RFS versus patients with NET G3 (median RFS: 35.6 vs. 33.9 months, p = 0.774).

CONCLUSIONS

Surgical resection provided acceptable short- and long-outcomes for well-selected patients with resectable GEP-NEN G3. NEC was associated with a worse OS versus NET G3.

New Nodal Staging for Primary Pancreatic Neuroendocrine Tumors: A Multi-institutional and National Data Analysis

OBJECTIVE

To determine the prognostic role of metastatic lymph node (LN) number and the minimal number of LNs for optimal staging of patients with pancreatic neuroendocrine tumors (pNETs).

BACKGROUND

Prognosis relative to number of LN metastasis (LNM), and minimal number of LNs needed to evaluate for accurate staging, have been poorly defined for pNETs.

METHODS

Number of LNM and total number of LN evaluated (TNLE) were assessed relative to recurrence-free survival (RFS) and overall survival (OS) in a multi-institutional database. External validation was performed using Surveillance, Epidemiology and End Results (SEER) registry.

RESULTS

Among 854 patients who underwent resection, 233 (27.3%) had at least 1 LNM. Patients with 1, 2, or 3 LNM had a comparable worse RFS versus patients with no nodal metastasis (5-year RFS, 1 LNM 65.6%, 2 LNM 68.2%, 3 LNM 63.2% vs 0 LNM 82.6%; all P < 0.001). In contrast, patients with ≥4 LNM (proposed N2) had a worse RFS versus patients who either had 1 to 3 LNM (proposed N1) or node-negative disease (5-year RFS, ≥4 LNM 43.5% vs 1-3 LNM 66.3%, 0 LNM 82.6%; all P < 0.05) [C-statistics area under the curve (AUC) 0.650]. TNLE ≥8 had the highest discriminatory power relative to RFS (AUC 0.713) and OS (AUC 0.726) among patients who had 1 to 3 LNM, and patients who had ≥4 LNM in the multi-institutional and SEER database (n = 2764).

CONCLUSIONS

Regional lymphadenectomy of at least 8 lymph nodes was necessary to stage patients accurately. The proposed nodal staging of N0, N1, and N2 optimally staged patients.

Recurrence of Non-functional Pancreatic Neuroendocrine Tumors After Curative Resection: A Tumor Burden-Based Prediction Model

BACKGROUND

Patients can experience recurrence following curative-intent resection of non-functional pancreatic neuroendocrine tumors (NF-pNETs). We sought to develop a nomogram to risk stratify patients relative to recurrence following resection of NF-pNETs.

METHODS

Patients who underwent curative-intent resection for NF-pNETs between 1997 and 2016 were identified from a multi-institutional database. The impact of clinicopathologic factors, including tumor burden score (TBS) (TBS² = (maximum tumor diameter)² + (number of tumors)²), was assessed relative to recurrence-free survival (RFS), and a nomogram was developed and internally validated.

RESULTS

With a median follow-up of 31.0 months (IQR 11.3-56.6 months), 66 (15.8%) out of 416 patients in the cohort experienced tumor recurrence. Overall, 3-, 5-, and 10-year RFS following curative-intent resection was 83.2%, 74.0%, and 44.7%, respectively. Several factors were associated with risk of recurrence including tumor grade (referent G1: G2, HR 4.07, 95% CI 2.29-7.26, p < 0.001; G3, HR 10.83, 95% CI 3.72-31.53, p < 0.001), lymph node metastasis (LNM) (HR 4.71, 95% CI 2.69-8.26, p < 0.001), as well as TBS (referent low: medium, HR 4.36, 95% CI 2.06-9.24, p < 0.001; high, HR 6.04, 95% CI 2.96-12.31, p < 0.001). A weighted nomogram including tumor grade (G1 0, G2 54.19, G3 100), LNM (N0 0, N1 42.06), and TBS (low 0, medium 44.07, high 56.48) was developed. The discriminatory power of the nomogram was very good with a C-index of 0.75 (95% CI, 0.66-0.79) in the training cohort and 0.71 (95% CI, 0.65-0.75) in the validation cohort. In addition, the nomogram performed better than the current 8th edition of AJCC TNM staging system, which had a C-index of 0.67 (95% CI, 0.60-0.73).

CONCLUSIONS

A nomogram that incorporated tumor grade, LNM, and TBS was established that had good discrimination and calibration. The nomogram may be an effective tool to stratify patients relative to recurrence risk following resection of NF-pNETs.

Theoretical and experimental study of peroxy and alkoxy radicals in the NO3-initiated oxidation of isoprene

Under atmospheric conditions, nitrate-RO₂ radicals are equilibrated and react predominantly with HO₂, RO₂ and NO. The nitrate-RO chemistry is affected strongly by ring closure to epoxy radicals, impeding formation of MVK/MACR.

Experimental and theoretical study on the impact of a nitrate group on the chemistry of alkoxy radicals

The chemistry of nitrated alkoxy radicals, and its impact on RO₂ measurements using the laser induced fluorescence (LIF) technique, is examined by a combined theoretical and experimental study.

Can Male Mice Develop Preference Towards Gentle Stroking by an Experimenter?

Gentle stroking, a type of affective touch that holds hedonic and rewarding value, is critical to our daily inter-individual communication. This positive socio-emotional aspect of touch is conveyed through a subclass of C afferents known as C-Tactile fibers in humans with an analogous system in rodents proposed. Here, we describe a novel tactile conditioned place preference paradigm using mice and demonstrate that gentle stroking by an experimenter is rewarding. In order to investigate the relationship between tactile preference and innate sociability, mice were subjected to the classic three-chambered test of social approach, where mice displayed significant preference towards the experimenter's hand. These findings suggest that gentle stroking evoked by an experimenter can play an important role in reward and preference and establish an affiliative relationship between mice and humans. Future research can potentially use this model to examine fiber type involvement and elucidate the significance of these findings for activation of the reward system.

Clinical relevance of performing endoscopic ultrasound-guided fine-needle biopsy for pancreatic neuroendocrine tumors less than 2 cm

BACKGROUND

We sought to define the diagnostic yield and concordance rates between endoscopic ultrasound (EUS)-fine-needle aspiration (FNA) and surgical pathology specimen following resection of pancreatic neuroendocrine tumors (pNET) less than 2 cm.

METHODS

Patients with a pNET less than 2 cm who underwent EUS-FNA were identified using a multi-institutional international database. Tumor differentiation, and Ki-67 index, as determined through EUS-FNA were examined and concordance rates between EUS-FNA and the surgical pathology were assessed.

RESULTS

Among 628 patients with a pNET less than 2 cm, 57.2% of patients had an EUS-FNA performed. Patients who underwent EUS had slightly smaller size tumors (1.3 vs 1.4 cm), and the pNETs were less likely to be functional (15.3% vs 26.8%) or symptomatic (48.5% vs 56.5%) (both P < .05). Among 314 patients with a pNET less than 2 cm who had an EUS-FNA performed at the time of diagnosis, 243 (73.2%) had the diagnosis confirmed by preoperative EUS-FNA. Tumor differentiation and Ki-67 could be determined by EUS-FNA in only 26.4% and 20.1% of patients, respectively. Concordance rate between EUS-FNA and pathology was high relative to tumor differentiation (92.7%) and Ki-67 (81.0%).

CONCLUSION

Tumor differentiation and Ki-67 index could be determined by EUS-FNA in only 26.4% and 20.1% of cases, respectively. Further studies should focus on EUS techniques to optimize diagnostic yield and cell extraction in the preoperative setting.

Tumor burden score predicts tumor recurrence of non-functional pancreatic neuroendocrine tumors after curative resection

BACKGROUND

To investigate the feasibility of Tumor Burden Score (TBS) to predict tumor recurrence following curative-intent resection of non-functional pancreatic neuroendocrine tumors (NF-pNETs).

METHOD

The TBS cut-off values were determined by a statistical tool, X-tile. The influence of TBS on recurrence-free survival (RFS) was examined.

RESULTS

Among 842 NF-pNETs patients, there was an incremental worsening of RFS as the TBS increased (5-year RFS, low, medium, and high TBS: 92.0%, 73.3%, and 59.3%, respectively; P < 0.001). TBS (AUC 0.74) out-performed both maximum tumor size (AUC 0.65) and number of tumors (AUC 0.5) to predict RFS (TBS vs. maximum tumor size, p = 0.05; TBS vs. number of tumors, p < 0.01). The impact of margin (low TBS: R0 80.4% vs. R1 71.9%, p = 0.01 vs. medium TBS: R0 55.8% vs. R1 37.5%, p = 0.67 vs. high TBS: R0 31.9% vs. R1 12.0%, p = 0.11) and nodal (5-year RFS, low TBS: N0 94.9% vs. N1 68.4%, p < 0.01 vs. medium TBS: N0 81.8% vs. N1 55.4%, p < 0.01 vs. high TBS: N0 58.0% vs. N1 54.2%, p = 0.15) status on 5-year RFS outcomes disappeared among patients who had higher TBS.

CONCLUSIONS

TBS was strongly associated with risk of recurrence and outperformed both tumor size and number alone.

Correction to: Trends in the Number of Lymph Nodes Evaluated Among Patients with Pancreatic Neuroendocrine Tumors in the United States: A Multi-Institutional and National Database Analysis

In the original article, Ryan C. Fields' middle initial is missing.

Resection of pancreatic neuroendocrine tumors: defining patterns and time course of recurrence

BACKGROUND

To define recurrence patterns and time course, as well as risk factors associated with recurrence following curative resection of pNETs.

METHOD

Patients who underwent curative-intent resection for pNET between 1997 and 2016 were identified from the US Neuroendocrine Tumor Study Group. Data on baseline and tumor-specific characteristics, overall survival (OS), timing and first-site of recurrence, predictors and recurrence management were analyzed.

RESULTS

Among 1020 patients, 154 (15.1%) patients developed recurrence. Among patients who experienced recurrence, 76 (49.4%) had liver-only recurrence, while 35 (22.7%) had pancreas-only recurrence. The proportion of liver-only recurrence increased from 54.3% within one-year after surgery to 61.5% from four-to-six years after surgery; whereas the proportion of pancreas-only recurrence decreased from 26.1% to 7.7% over these time periods. While liver-only recurrence was associated with tumor characteristics, pancreas-only recurrence was only associated with surgical margin status. Patients undergoing curative resection of recurrence had comparable OS with patients who had no recurrence (median OS, pancreas-only recurrence, 133.9 months; liver-only recurrence, not attained; no recurrence, 143.0 months, p = 0.499) CONCLUSIONS: Different recurrence patterns and timing course, as well as risk factors suggest biological heterogeneity of pNET recurrence. A personalized approach to postoperative surveillance and treatment of recurrence disease should be considered.

Trends in the Number of Lymph Nodes Evaluated Among Patients with Pancreatic Neuroendocrine Tumors in the United States: A Multi-Institutional and National Database Analysis

BACKGROUND

The role of routine lymphadenectomy in the surgical treatment of pancreatic neuroendocrine tumors (pNET) remains poorly defined. The objective of the current study was to investigate trends in the number of lymph nodes (LN) evaluated for pNET treatment at a nationwide level.

METHODS

Patients undergoing surgery for pNET between 2000 and 2016 were identified in the U.S. Neuroendocrine Tumor Study Group (US-NETSG) database as well as the Surveillance, Epidemiology, and End Results (SEER) database. The number of LNs examined was evaluated over time.

RESULTS

The median number of evaluated LNs increased roughly fourfold over the study period (US-NETSG, 2000: 3 LNs vs. 2016: 13 LNs; SEER, 2000: 3 LNs vs. 2016: 11 LNs, both p < 0.001). While no difference in 5-year OS and RFS was noted among patients who had 1-3 lymph node metastases (LNM) vs. ≥ 4 LNM between 2000-2007 (OS 73.5% vs. 69.9%, p = 0.12; RFS: 64.9% vs. 40.1%, p = 0.39), patients who underwent resection and LN evaluation during the period 2008-2016 had an incrementally worse survival if the patient had node negative disease, 1-3 LNM and ≥ 4 LNM (OS 86.8% vs. 82.7% vs. 74.9%, p < 0.001; RFS: 86.3% vs. 64.7% vs. 50.4%, p < 0.001). On multivariable analysis, a more recent year of diagnosis, pancreatic head tumor location, and tumor size > 2 cm were associated with 12 or more LNs evaluated in both US-NETSG and SEER databases.

CONCLUSION

The number of LNs examined nearly quadrupled over the last decade. The increased number of LNs examined suggested a growing adoption of the AJCC staging manual recommendations regarding LN evaluation in the treatment of pNET.

Duodenal neuroendocrine tumors: Impact of tumor size and total number of lymph nodes examined

BACKGROUND

The current study sought to investigate the impact of tumor size and total number of LN examined (TNLE) on the incidence of lymph node metastasis (LNM) among patients with duodenal neuroendocrine tumor (dNET).

METHODS

Patients who underwent curative resection for dNETs between 1997-2016 were identified from 8 high-volume US centers. Risk factors associated with overall survival and LNM were identified and the optimal cut-off of TNLE relative to LNM was determined.

RESULTS

Among 162 patients who underwent resection of dNETs, median patient age was 59 (interquartile range [IQR], 51-68) years and median tumor size was 1.2 cm (IQR, 0.7-2.0 cm); a total of 101 (62.3%) patients underwent a concomitant LND at the time of surgery. Utilization of lymphadenectomy (LND) increased relative to tumor size (≤1 cm:52.2% vs 1-2 cm:61.4% vs >2 cm:93.8%; P < .05). Similarly, the incidence of LNM increased with dNET size (≤1 cm: 40.0% vs 1-2 cm:65.7% vs >2 cm:80.0%; P < .05). TNLE ≥ 8 had the highest discriminatory power relative to the incidence of LNM (area under the curve = 0.676). On multivariable analysis, while LNM was not associated with prognosis (hazard ratio [HR] = 0.9; 95% confidence intervals [95%CI], 0.4-2.3), G2/G3 tumor grade was (HR = 1.5; 95%CI, 1.0-2.1).

CONCLUSIONS

While the incidence of LNM directly correlated with tumor size, patients with dNETs ≤ 1 cm had a 40% incidence of LNM. Regional lymphadenectomy of a least 8 LN was needed to stage patients accurately.

Impact of tumor size and nodal status on recurrence of nonfunctional pancreatic neuroendocrine tumors ≤2 cm after curative resection: A multi‐institutional study of 392 cases

BACKGROUND

The current study sought to define the impact of lymph node metastasis (LNM) relative to tumor size on tumor recurrence after curative resection for nonfunctional pancreatic neuroendocrine tumors (NF-pNETs) ≤2 cm.

METHODS

Patients who underwent curative resection for ≤2-cm NF-pNETs were identified from a multi-institutional database. Risk factors associated with tumor recurrence as well as LNM were identified. Recurrence-free survival (RFS) was compared among patients with or without LNM.

RESULTS

A total of 392 ≤2-cm NF-pNETs patients were identified. Among the 328 patients who had lymph node dissection and evaluation, 42 (12.8%) patients had LNM. LNM was associated with tumor recurrence (hazard ratio, 3.06; P = .026) after surgery. RFS was worse among LNM vs no LNM patients (5-year RFS, 81.7% vs 94.1%; P = .019). Patients with tumors measuring 1.5-2 cm had a two-fold increase in the incidence of LNM vs patients with tumors <1.5 cm (17.9% vs 8.7%, odds ratio, 2.59; P = .022), as well as a higher risk of advanced tumor grade and higher Ki-67 levels (both P < .01). After curative resection, a total of 14 (8.0%) patients with a tumor of 1.5-2 cm and 10 (4.5%) patients with tumor <1.5 cm developed tumor recurrence.

CONCLUSION

Surgical resection with lymphadenectomy should be considered for patients with NF-pNETs ≥1.5-2.0 cm.

Minimally invasive versus open distal pancreatectomy for pancreatic neuroendocrine tumors: An analysis from the U.S. neuroendocrine tumor study group

BACKGROUND

To determine short- and long-term oncologic outcomes after minimally invasive distal pancreatectomy (MIDP) with open distal pancreatectomy (ODP) for the treatment of pancreatic neuroendocrine tumor (pNET).

METHODS

The data of the patients who underwent curative MIDP or ODP for pNET between 2000 and 2016 were collected from a multi-institutional database. Propensity score matching (PSM) was used to generate 1:1 matched patients with MIDP and ODP.

RESULTS

A total of 576 patients undergoing curative DP for pNET were included. Two hundred and fourteen (37.2%) patients underwent MIDP, whereas 362 (62.8%) underwent ODP. MIDP was increasingly performed over time (2000-2004: 9.3% vs 2013-2016: 54.8%; P < 0.01). In the matched cohort (n = 141 in each group), patients who underwent MIDP had less blood loss (median, 100 vs 200 mL, P < 0.001), lower incidence of Clavien-Dindo ≥ III complications (12.1% vs 24.8%, P = 0.026), and a shorter hospital stay versus ODP (median, 4 versus 7 days, P = 0.026). Patients who underwent MIDP had a lower incidence of recurrence (5-year cumulative recurrence, 10.1% vs 31.1%, P < 0.001), yet equivalent overall survival (OS) rate (5-year OS, 92.1% vs 90.9%, P = 0.550) compared with patients who underwent OPD.

CONCLUSION

Patients undergoing MIDP over ODP in the treatment of pNET had comparable oncologic surgical metrics, as well as similar long-term OS.

Margin status and long-term prognosis of primary pancreatic neuroendocrine tumor after curative resection: Results from the US Neuroendocrine Tumor Study Group

BACKGROUND

The impact of margin status on resection of primary pancreatic neuroendocrine tumors has been poorly defined. The objectives of the present study were to determine the impact of margin status on long-term survival of patients with pancreatic neuroendocrine tumors after curative resection and evaluate the impact of reresection to obtain a microscopically negative margin.

METHODS

Patients who underwent curative-intent resection for pancreatic neuroendocrine tumors between 2000 and 2016 were identified at 8 hepatobiliary centers. Overall and recurrence-free survival were analyzed relative to surgical margin status using univariable and multivariable analyses.

RESULTS

Among 1,020 patients, 866 (84.9%) had an R0 (>1 mm margin) resection, whereas 154 (15.1%) had an R1 (≤1 mm margin) resection. R1 resection was associated with a worse recurrence-free survival (10-year recurrence-free survival, R1 47.3% vs R0 62.8%, hazard ratio 1.8, 95% confidence interval 1.2-2.7, P = .002); residual tumor at either the transection margin (R1t) or the mobilization margin (R1m) was associated with increased recurrence versus R0 (R1t versus R0: hazard ratio 1.8, 95% confidence interval 1.0-3.0, P = .033; R1m versus R0: hazard ratio 1.3, 95% confidence interval 1.0-1.7, P = .060). In contrast, margin status was not associated with overall survival (10-year overall survival, R1 71.1% vs R0 71.8%, P = .392). Intraoperatively, 539 (53.6%) patients had frozen section evaluation of the surgical margin; 49 (9.1%) patients had a positive margin on frozen section analysis; 38 of the 49 patients (77.6%) had reresection, and a final R0 (secondary R0) margin was achieved in 30 patients (78.9%). Extending resection to achieve an R0 status remained associated with worse overall survival (hazard ratio 3.1, 95% confidence interval 1.6-6.2, P = .001) and recurrence-free survival (hazard ratio 2.6, 95% confidence interval 1.4-5.0, P = .004) compared with primary R0 resection. On multivariable analyses, tumor-specific factors, such as cellular differentiation, perineural invasion, Ki-67 index, and major vascular invasion, rather than surgical margin, were associated with long-term outcomes.

CONCLUSION

Margin status was not associated with long-term survival. The reresection of an initially positive surgical margin to achieve a negative margin did not improve the outcome of patients with pancreatic neuroendocrine tumors. Parenchymal-sparing pancreatic procedures for pancreatic neuroendocrine tumors may be appropriate when feasible.

Nomogram predicting the risk of recurrence after curative-intent resection of primary non-metastatic gastrointestinal neuroendocrine tumors: An analysis of the U.S. Neuroendocrine Tumor Study Group

BACKGROUND

The risk of recurrence after resection of non-metastatic gastro-entero-pancreatic neuroendocrine tumors (GEP-NET) is poorly defined. We developed/validated a nomogram to predict risk of recurrence after curative-intent resection.

METHODS

A training set to develop the nomogram and test set for validation were identified. The predictive ability of the nomogram was assessed using c-indices.

RESULTS

Among 1477 patients, 673 (46%) were included in the training set and 804 (54%) in y the test set. On multivariable analysis, Ki-67, tumor size, nodal status, and invasion of adjacent organs were independent predictors of DFS. The risk of death increased by 8% for each percentage increase in the Ki-67 index (HR 1.08, 95% CI, 1.05-1.10; P < 0.001). GEP-NET invading adjacent organs had a HR of 1.65 (95% CI, 1.03-2.65; P = 0.038), similar to tumors ≥3 cm (HR 1.67, 95% CI, 1.11-2.51; P = 0.014). Patients with 1-3 positive nodes and patients with >3 positive nodes had a HR of 1.81 (95% CI, 1.12-2.87; P = 0.014) and 2.51 (95% CI, 1.50-4.24; P < 0.001), respectively. The nomogram demonstrated good ability to predict risk of recurrence (c-index: training set, 0.739; test set, 0.718).

CONCLUSION

The nomogram was able to predict the risk of recurrence and can be easily applied in the clinical setting.

Systemic therapy in incurable gastroenteropancreatic neuroendocrine tumours: a clinical practice guideline

PURPOSE

The purpose of the present review was to determine which antineoplastic systemic therapy is most effective in improving clinical outcomes for patients with incurable gastroenteropancreatic neuroendocrine tumours (nets).

METHODS

A systematic search (2008-2016) of the literature in the medline and embase databases and the Cochrane Database of Systematic Reviews was conducted; abstracts from the American Society of Clinical Oncology, the American Society of Clinical Oncology Gastrointestinal Cancers Symposium, the European Society for Medical Oncology, the European Cancer Congress, the European Neuroendocrine Tumor Society, and the North American Neuroendocrine Tumor Society were reviewed. Draft recommendations were created, and a comprehensive review process was undertaken. Outcomes-including progression-free survival (pfs), overall survival, objective response rate, adverse events, and quality of life-were extracted from each of the studies.

RESULTS

Eleven randomized controlled trials (rcts), sixteen nonrandomized prospective studies, and thirteen retrospective studies met the inclusion criteria.

CONCLUSIONS

Patients with well-or moderately-differentiated pancreatic nets (pnets) should receive targeted therapy (that is, everolimus or sunitinib), and patients with non-pnets should be offered either targeted therapy (that is, everolimus) or somatostatin analogues (ssas-that is, octreotide long-acting release or lanreotide). Evidence from two phase iii trials demonstrated a significant pfs benefit for patients with pnets. For patients with non-pnets, the evidence comes from subgroup analyses of rcts, as well as from a planned interim analysis. Although the evidence has limitations, the rarity of the disease, coupled with the difficulty of conducting methodologically sound trials in the affected population, means that treatment decisions have to make use of the best available evidence. Because of insufficient evidence for both pnets and non-pnets, no evidence-based recommendation can be made for or against other types of targeted therapy, other ssas, chemotherapy, or combination therapy.

Prevalence and risk factors of chronic rhinosinusitis in South Korea according to diagnostic criteria

BACKGROUND

We aimed to compare the prevalence and risk factors of chronic rhinosinusitis (CRS) using two different diagnostic criteria with the same statistical data from the Korean National Health and Nutrition Examination Survey in 2009.

METHODS

Symptom-based CRS was defined as CRS diagnosed by questionnaires related to nasal symptoms. Endoscopy-based CRS was defined based on endoscopic findings and nasal symptoms of symptom-based CRS.

RESULTS

The overall prevalence of CRS based on the different diagnostic criteria was as follows: symptom-based CRS was 10.78% (797 of 7,394) and endoscopy-based CRS was 1.20% (88 of 7,343). Comparing symptom-based CRS to endoscopy-based CRS showed slight agreement (kappa = 0.183 (0.150-0.216, 95% confidence interval)). Allergic rhinitis was identified as a common risk factor for CRS based on the two diagnostic criteria.

CONCLUSIONS

The prevalence and risk factors of CRS were quite different from each other according to the different criteria, even in the same population. Therefore, it would be important to consider what specific diagnostic criteria have been adopted in the studies comparing the prevalence of CRS.

Sophorae radix reduces autoimmune response in NZB/w F1 systemic lupus erythematosus mouse model

The immunosuppressive effects of Sophorae radix (SR) make this plant an attractive agent for the treatment of autoimmune diseases. The effect of SR on systemic lupus erythematosus (SLE) in the New Zealand Black/White F1 (NZB/w F1) mouse model system was investigated. Three-month-old NZB/w F1 mice were separated into two groups: one treated with SR (1% SR solution by oral administration, daily for 15 weeks) and one with water as a control. Experimental parameters include proteinuria, anti-dsDNA antibody titers, T-cell response and renal histopathological analysis. Results in the SR-treated group showed a significant reduction in proteinuria and anti-dsDNA antibodies either in serum or in glomerular capillaries, along with significant recovery from renal glomerular damage. The lymphocyte population was significantly increased in the SR-treated mice compared with the control group. In the T helper (Th)1/Th2 cytokine secretion profile, interferon-γ in splenocyte culture was significantly reduced in the SR-treated mice, while interleukin-4 secretion was not altered. These results strongly suggest SR therapy corrects the deviated Th1/Th2 balance, thereby alleviating SLE-like symptoms in the NZB/w F1 mice. Therefore, SR may be useful in the clinical treatment of SLE. Lupus (2007) 16, 335—341.