Reinforced staplers for distal pancreatectomy

PURPOSE

The safety and efficacy of reinforced staplers during distal pancreatectomy (DP) remain controversial because of the small sample size. This multicenter single-arm prospective study aims to evaluate the safety and efficacy of reinforced staplers with bioabsorbable material during DP.

METHODS

Between October 2014 and August 2015, 121 patients scheduled for DP were enrolled in this study at 11 institutions in Japan. The primary endpoint was the incidence of clinically relevant pancreatic fistula. Protocol treatment was defined as "distal pancreatectomy using reinforced staplers."

RESULTS

Per-protocol analysis of 105 patients was performed; 16 of the patients were excluded based on discontinuation of protocol treatment criteria. Clinically relevant pancreatic fistula occurred in 13 (12.4%) of 105 patients. The overall morbidity rate was 29.5% (31 of 105 patients) and severe complication (Clavien classification IIIa or more) was 10.5% (11/105). Mortality rate was 0%, although reoperations were performed on two patients (1.9%). Multivariate logistic regression analysis of independent risk factors for clinically relevant pancreatic fistula after DP using reinforced stapler closure was operative time more than 240 min (P = 0.047, odds ratio 5.79), registration numbers less than 10 (P = 0.046, odds ratio 13.01), and staple line hemorrhage (P = 0.003, odds ratio 16.34).

CONCLUSION

This study confirms the safety of reinforced staplers for pancreatic stump closure during DP. However, the efficacy of reinforced staplers for decreasing clinically relevant pancreatic fistula could not be drawn from this study.

TRIAL REGISTRATION

This prospective study was registered with ClinicalTrials.gov (NCT02270554) and UMIN Clinical Trial Registry (UMIN000015384).

Retrospective Study of the Correlation Between Pathological Tumor Size and Survival After Curative Resection of T3 Pancreatic Adenocarcinoma: Proposal for Reclassification of the Tumor Extending Beyond the Pancreas Based on Tumor Size

BACKGROUND

Even though most patients who undergo resection of pancreatic adenocarcinoma have T3 disease with extra-pancreatic tumor extension, T3 disease is not currently classified by tumor size. The aim of this study was to modify the current TNM classification of pancreatic adenocarcinoma to reflect the influence of tumor size.

METHODS

A total of 847 consecutive pancreatectomy patients were recruited from multiple centers. Optimum tumor size cutoff values were calculated by receiver operating characteristics analysis for tumors limited to the pancreas (T1/2) and for T3 tumors. In our modified TNM classification, stage II was divided into stages IIA (T3aN0M0), IIB (T3bN0M0), and IIC (T1-3bN1M0) using tumor size cutoff values. The usefulness of the new classification was compared with that of the current classification using Akaike's information criterion (AIC).

RESULTS

The optimum tumor size cutoff value distinguishing T1 and T2 was 2 cm, while T3 was divided into T3a and T3b at a tumor size of 3 cm. The median survival time of the stages IIA, IIB, and IIC were 44.7, 27.6, and 20.3 months, respectively. There were significant differences of survival between stages IIA and IIB (P = 0.02) and between stages IIB and IIC (P = 0.03). The new classification showed better performance compared with the current classification based on the AIC value.

CONCLUSIONS

This proposed new TNM classification reflects the influence of tumor size in patients with extra-pancreatic tumor extension (T3 disease), and the classification is useful for predicting mortality.

Duodenogastric regurgitation in hepaticoduodenostomy after excision of congenital biliary dilatation (choledochal cyst)

PURPOSE

We examined the clinical significance of duodenogastric regurgitation (DGR) as a late complication in the long-term follow-up after hepaticoduodenostomy (HD) as a reconstruction surgery for congenital biliary dilatation (CBD).

METHODS

Seventeen patients with CBD were retrospectively analyzed for late complications (mean follow-up, 16.8 years). All patients had undergone total resection of the extrahepatic bile duct followed by HD. DGR was identified using endoscopic examination, intraluminal bile monitoring, and liver scanning.

RESULTS

DGR was found in all 17 patients by endoscopic examination and intraluminal bile monitoring. Fourteen of the 17 (82.4%) patients with DGR had experienced abdominal symptoms since a mean of 6.9 years postoperatively. Liver scanning also revealed apparent DGR in all 14 symptomatic patients. We converted 7 of the 14 patients to hepaticojejunostomy reconstruction at a mean of 13.0 years after the initial excisional surgery. Their symptoms were completely relieved postoperatively.

CONCLUSIONS

DGR is an important complication after HD. Examination of patients for the development of DGR is an essential part of long-term follow-up in patients with CBD who have undergone HD as a reconstruction surgery. Conversion surgery is recommended in patients with DGR accompanied by long-term abdominal symptoms.

LEVELS OF EVIDENCE

Level IV.

Combination therapies for primary hepatic neuroendocrine carcinoma: a case report

Background

Primary hepatic neuroendocrine carcinomas are extremely rare. Because of the rarity of PHNEC, its clinical features and treatment outcomes are not well understood. A proper diagnosis and the correct therapeutic approach therefore remain clinically challenging.

Case presentation

A 67-year-old man was admitted to our department because of a liver tumor. Computed tomography revealed a single liver tumor 50 mm in diameter and located in the S3 region. Biopsy and imaging findings resulted in a diagnosis of primary hepatic neuroendocrine carcinoma. Left lateral segmentectomy was performed. Immunohistochemically, the tumor cells were positive for synaptophysin, chromogranin A, and CD56. Ki-67 was positive in > 90% of the tumor cells. The final diagnosis was primary hepatic neuroendocrine carcinoma. The patient suffered two episodes of lymph node recurrence. Nonetheless, the tumor was excised to prolong survival. Thus, after lymphadenectomy, he received adjuvant chemotherapy for 6 months. Two years after surgery, the patient remains alive and in good general condition.

Conclusions

In most cases, primary hepatic neuroendocrine carcinoma, while extremely rare, has a poor prognosis. At present, surgical resection is a priority for curative treatment, but in patients with recurrence, combined therapies are recommended.

Developing better practices at the institutional level leads to better outcomes after pancreaticoduodenectomy in 3,378 patients: domestic audit of the Japanese Society of Pancreatic Surgery

BACKGROUND

The aim of the present study was to assess recent trends in pancreaticoduodenectomy (PD) and the role of institutional standardization on the development of postoperative complications in 3,378 patients who underwent PD in Japan.

METHODS

Data were collected from 3,378 patients who underwent PD in 2006, 2010 and 2014 at 53 institutions. A standardized institution (SI) was defined as one that implements ≥7 of 13 quality initiatives according to departmental policy. There were 1,223 patients in the SI group and 2,155 in the non-SI group. Clinical parameters were compared over time, and between groups. Risk factors for morbidity and mortality were assessed by logistic regression analysis with a mixed-effects model.

RESULTS

The number of patients who underwent PD in SIs increased from 16.5% in 2006 to 46.4% in 2014. The SI group experienced an improved process of care and a lower frequency of severe complications vs. the non-SI group (P < 0.001). Multivariate analysis revealed that the SI group was associated with a lower incidence of delayed gastric emptying (odds ratio -0.499, P = 0.008) and incisional surgical site infection (odds ratio -0.999, P < 0.001).

CONCLUSION

Standardization of care in PD may be important in reducing post-PD complications, and is a critical element for improving clinical outcomes.

Effect of inflammatory and nutritional (IN) status on induction chemotherapy (CT) followed by chemoradiotherapy (CRT) for locally advanced pancreatic cancer (LAPC): An exploratory subgroup analysis of JCOG1106

4123

Background: JCOG1106 is a randomized selection phase 2 trial to evaluate the efficacy and safety of CRT (S-1 concurrent RT) with (Arm B) or without (Arm A) induction CT of gemcitabine (GEM) for LAPC. In the final analysis, we selected Arm A as a promising regimen due to a poorer 2-year overall survival (OS) of Arm B, in spite of a favorable 1-year OS with crossing of the survival curves around 1-year (Ioka, ESMO2016). Therefore, this study aimed to explore subgroups benefit more from either treatment. IN statuses defined by such as serum C-reactive protein (CRP) and serum albumin (Alb) are recognized as prognostic and predictive factors in patients (pts) with various cancers receiving CT or CRT. We hypothesized that IN status may modify the effect of induction CT. Methods: Subjects were all eligible pts who were enrolled in JCOG1106 (n = 51/49 in Arm A/B). Glasgow Prognostic Score (GPS) was classified by baseline CRP and Alb. Pts with a CRP ≤ 10 mg/L and Alb ≥ 35 g/L were allocated to GPS 0, with a CRP > 10 mg/L or Alb < 35 g/L to GPS 1, and with a CRP > 10 mg/L and Alb < 35 g/L to GPS 2. This exploratory subgroup analysis was performed by Cox regression analysis to investigate the impact of IN status at baseline on OS. Less than 0.1 of P-value for interaction was regarded as significant. Results: GPS, CRP and Alb showed significant treatment interactions in terms of OS. HRs of Arm B to Arm A were 1.35 (0.82–2.23) and 0.59 (0.24–1.50) in the GPS 0 (n = 44/34 in Arm A/B) and GPS 1/2 group (n = 7/15) ( P-interaction = 0.06). HRs were 2.57 (1.36–4.86) and 0.70 (0.37–1.32) in the low CRP group (≤ 1.35 mg/L, n = 25/25) and high CRP ( > 1.35 mg/L, n = 26/24) ( P= 0.01). HRs were 1.62 (0.77–3.40), 2.70 (1.17–6.23) and 0.52 (0.24–1.13) in the 1st (≤ 0.7 mg/L, n = 16/16), 2nd ( > 0.7, ≤ 3.0 mg/L, n = 20/16), and 3rd tertiary CRP group ( > 3.0 mg/L, n = 15/17) ( P= 0.01). HRs were 2.29 (1.11–4.69) and 0.89 (0.51–1.54) in the high Alb group ( > 40 g/L, n = 23/17) and low Alb (≤ 40 g/L, n = 28/32) ( P= 0.04). Arm B showed better survival in subgroups of GPS 1/2, higher CRP or lower Alb compared to Arm A. Conclusions: Pts with poor IN status may have treatment benefit of induction CT followed by CRT for LAPC. Clinical trial information: UMIN000006811.

A randomized phase III trial comparing adjuvant chemotherapy with S-1 vs. surgery alone in patients with resectable biliary tract cancer (JCOG1202: ASCOT)

TPS4144

Background: No standard adjuvant treatment has been established for patients with curatively resected biliary tract cancer (BTC). S-1, which is one of the oral fluoropyrimidine derivatives, showed promising efficacy with a mild toxicity profiles in patients with advanced BTC, and the survival benefit of adjuvant S-1 therapy has been demonstrated in patients with resected gastric cancer and pancreatic cancer. The aim of this open-label, multicenter, randomized phase III trial is to assess whether adjuvant S-1 would prolong the overall survival in patients with resected BTC. Methods: The main eligibility criteria are as follows: 1) curatively resected carcinoma of the extrahepatic bile duct, gallbladder or ampulla of Vater (T2-4, N0, M0 or T1-4, N1, M0), or carcinoma of the intrahepatic bile duct (T1-4, N0-1, M0) (7th UICC classification), 2) histologically confirmed adeno (squamous) carcinoma, 3) R0 or R1 residual disease, 4) age 20 to 80 years, 5) ECOG performance status 0 or 1, 6) no prior chemotherapy or radiotherapy, 7) adequate organ functions, 8) written informed consent. Patients are randomly assigned to the surgery alone arm (arm A) or the adjuvant S-1 arm (arm B) by the minimization method for balancing institution, primary site of cancer and lymph node metastasis between the arms. Patients in arm A do not receive any anti-cancer treatment, while patients in arm B receive 4 cycles of oral S-1 chemotherapy at the dose of 40 mg/m2 twice daily for 4 weeks followed by 2 weeks of rest. The primary endpoint is overall survival, while the secondary endpoints are relapse-free survival, incidence of (serious) adverse events, and proportion of treatment completion. We assumed a 3-year survival in arm A of 47% and a 10% increase in the 3-year survival in arm B. The sample size was calculated as a total of 350, with a one-side alpha of 5% and power of 70%; planned accrual period is 4 years, and follow-up period, 3 years. Primary analysis will be conducted at 3 years and updated analysis will be conducted at 5 years after closing of accrual. As of Jan 31, 2016, a total of 285 patients have already been enrolled in this trial from Sep 2013. Clinical trial information: UMIN000011688.

Rb Loss and KRAS Mutation Are Predictors of the Response to Platinum-Based Chemotherapy in Pancreatic Neuroendocrine Neoplasm with Grade 3: A Japanese Multicenter Pancreatic NEN-G3 Study

Purpose: Patients with pancreatic neuroendocrine neoplasm grade-3 (PanNEN-G3) show variable responses to platinum-based chemotherapy. Recent studies indicated that PanNEN-G3 includes well-differentiated neuroendocrine tumor with G3 (NET-G3). Here, we examined the clinicopathologic and molecular features of PanNEN-G3 and assessed the responsiveness to chemotherapy and survival.Experimental Design: A total of 100 patients with PanNEN-G3 were collected from 31 institutions, and after central review characteristics of each histologic subtype [NET-G3 vs. pancreatic neuroendocrine carcinoma (NEC-G3)] were analyzed, including clinical, radiological, and molecular features. Factors that correlate with response to chemotherapy and survival were assessed.Results: Seventy patients analyzed included 21 NETs-G3 (30%) and 49 NECs-G3 (70%). NET-G3 showed lower Ki67-labeling index (LI; median 28.5%), no abnormal Rb expression (0%), and no mutated KRAS (0%), whereas NEC-G3 showed higher Ki67-LI (median 80.0%), Rb loss (54.5%), and KRAS mutations (48.7%). Chemotherapy response rate (RR), platinum-based chemotherapy RR, and prognosis differed significantly between NET-G3 and NEC-G3. Chemotherapeutic outcomes were worse in NET-G3 (P < 0.001). When we stratified PanNEN-G3 with Rb and KRAS, PanNENs-G3 with Rb loss and those with mutated KRAS showed significantly higher RRs to platinum-based chemotherapy than those without (Rb loss, 80% vs. normal Rb, 24%, P = 0.006; mutated KRAS, 77% versus wild type, 23%, P = 0.023). Rb was a predictive marker of response to platinum-based chemotherapy even in NEC-G3 (P = 0.035).Conclusions: NET-G3 and NEC-G3 showed distinct clinicopathologic characteristics. Notably, NET-G3 does not respond to platinum-based chemotherapy. Rb and KRAS are promising predictors of response to platinum-based chemotherapy for PanNEN-G3, and Rb for NEC-G3. Clin Cancer Res; 23(16); 4625-32. ©2017 AACR.

Multicenter, randomized, open-label Phase II study comparing S-1 alternate-day oral therapy with the standard daily regimen as a first-line treatment in patients with unresectable advanced pancreatic cancer

PURPOSE

Non-inferiority for overall survival (OS) following alternate-day treatment with the oral anticancer drug S-1 compared with standard daily treatment was assessed in Japanese patients with unresectable advanced pancreatic cancer in a multicenter, randomized, phase II study. This trial was registered at the UMIN Clinical Trials Registry (no. 000008604).

METHODS

Chemotherapy-naïve patients with locally advanced or metastatic pancreatic cancer were randomly assigned 2:1 to treatment with alternate-day (twice daily on alternate days from days 1 through 42 of a 42-day cycle) or daily (twice daily on days 1 through 28 of a 42-day cycle) treatment with S-1. The primary endpoint was OS. Secondary endpoints were progression-free survival (PFS), time to treatment failure, response rate, quality of life assessments, and safety.

RESULTS

A total of 190 patients were enrolled, of which 185 were included in the final analysis (alternate-day: 121; daily: 64). Median OS was 9.4 for the alternate-day group and 10.4 months for the daily group [hazard ratio (HR), 1.19; 95% credible interval, 0.86 to 1.64], indicating that non-inferiority of alternate-day treatment to daily treatment was not demonstrated. Median PFS was 3.0 for the alternate-day group and 4.2 months for the daily group (HR, 1.65; 95% credible interval, 1.20-2.29). The incidence of anorexia, fatigue, neutrophils, pigmentation, and pneumonitis was lower in alternate-day treatment compared with daily treatment.

CONCLUSION

S-1 for advanced pancreatic cancer should be taken daily as recommended, based on the decreased OS and PFS and marginal improvement in safety observed in the alternate-day group.

Survival benefit of intravenous and intraperitoneal paclitaxel with S-1 in pancreatic ductal adenocarcinoma patients with peritoneal metastasis: a retrospective study in a single institution

BACKGROUND

We evaluated the clinical efficacy of intravenous (i.v.) and intraperitoneal (i.p.) paclitaxel (PTX) combined with S-1 in patients with chemotherapy-naïve pancreatic ductal adenocarcinoma (PDAC) with peritoneal metastasis.

METHODS

Forty-nine patients were diagnosed with peritoneal metastasis during 2007-2014; 29 received gemcitabine or S-1-based chemo(radio)therapy from 2007 to 2011 (control group), and the remaining 20 received i.v. (50 mg/m² ) and i.p. (20 mg/m² ) PTX on days 1 and 8, and S-1 at 80 mg/m² per day for 14 consecutive days, followed by 7 days of rest from 2012 to 2014 (study group).

RESULTS

The median survival time in the study group was significantly longer than that in the control group (20 vs. 10 months, respectively; P = 0.004). At 1 year after initial treatment, a significant difference in ascites development on CT was found between the study (5/20 patients) and the control group (18/29 patients, P = 0.009). The frequency of objective response (9/20 patients) and conversion surgery (6/20 patients) in the study group was higher than those in the control group (8/29 and 2/29, respectively). Patients who underwent conversion surgery had improved survival in both groups.

CONCLUSION

Implementation of the S-1+i.v./i.p. PTX regimen was closely associated with improved overall survival in PDAC patients with peritoneal metastasis.

Risk factors for latent distant organ metastasis detected by staging laparoscopy in patients with radiologically defined locally advanced pancreatic ductal adenocarcinoma

OBJECTIVES

We aimed to identify risk factors for latent distant organ metastasis in patients with radiographically defined locally advanced (RDLA) pancreatic ductal adenocarcinoma (PDAC).

METHODS

RDLA disease was defined as unresectable disease without distant organ metastasis based on resectability status by NCCN guidelines. Between January 2005 and November 2015, 110 consecutive patients underwent staging laparoscopy to rule out latent distant metastasis. Univariate and multivariate analyses were performed to identify risk factors for latent distant organ metastasis or peritoneal metastasis (PM), defined as peritoneal dissemination and/or positive peritoneal lavage cytology (PPC).

RESULTS

Latent distant organ metastasis was diagnosed by staging laparoscopy in 62 patients. PPC was found in 23%, peritoneal dissemination in 19%, and liver metastasis in 15%. Univariate analysis showed tumor location, preoperative CA 19-9 level and tumor size, and multivariate analysis revealed tumor size >55 mm and CA 19-9 level >60 IU/ml as risk factors for latent distant metastasis. Multivariate analysis showed pancreas body-tail tumors and tumor size >42 mm as risk factors for PM; 65.4% of pancreas body-tail tumors >42 mm had PM.

CONCLUSIONS

Patients with large pancreas body-tail tumors and high CA 19-9 level are at greater risk for latent distant organ metastasis or PM, and should undergo staging laparoscopy routinely for accurate diagnosis (UMIN000023125).

Acute median arcuate ligament syndrome after pancreaticoduodenectomy

Median arcuate ligament syndrome (MALS) has been reported in 2–7.6 % of patients undergoing pancreaticoduodenectomy (PD). Most of the reported cases of MALS have been diagnosed perioperatively and treated radiologically or surgically before or during PD. MALS can have an acute postoperative onset after PD even if all preoperative and intraoperative evaluations are normal particularly in young patients.

In this report, we present a second case of severe hepatic cytolysis secondary to MALS that developed acutely and the first patient who required acute division of the median arcuate ligament after PD.

Clinical outcomes of pancreatic ductal adenocarcinoma resection following neoadjuvant chemoradiation therapy vs. chemotherapy

PURPOSE

We compared the clinical outcomes of pancreatic ductal adenocarcinoma (PDAC) resection after neoadjuvant chemoradiation therapy (NACRT) vs. chemotherapy (NAC).

METHODS

The study population comprised 81 patients with UICC stage T3/4 PDAC, treated initially by NACRT with S-1 in 40 and by NAC with gemcitabine + S-1 in 41. This was followed by pancreatectomy with routine nerve plexus resection in 35 of the patients who had received NACRT and 32 of those who had received NAC. We compared the survival curves and clinical outcomes of these two groups.

RESULTS

The rates of clinical response, surgical resectability, and margin-negative resection were similar. The NACRT group patients had significantly higher rates of Evans stage ≥IIB tumors (29 vs. 0 %, respectively, p = 0.010) and negative lymph nodes (49 vs. 16 %, respectively, p = 0.021) than the NAC group patients. There was no difference in disease-free survival between the groups, but the disease-specific survival of the NAC group patients was better than that of the NACRT group patients (p = 0.034). Patients undergoing pancreatectomy with nerve plexus resection following NACRT had significantly higher rates of intractable diarrhea and ascites but consequently received significantly less adjuvant chemotherapy and therapeutic chemotherapy for relapse.

CONCLUSION

NACRT followed by pancreatectomy with nerve plexus resection is superior for achieving local control, but postoperative diarrhea and ascites may prohibit continuation of adjuvant chemotherapy or chemotherapy for relapse (UMIN4148).

Alleviating Effect of Active Hexose Correlated Compound (AHCC) on Chemotherapy-Related Adverse Events in Patients with Unresectable Pancreatic Ductal Adenocarcinoma

The present study was conducted to determine whether active hexose correlated compound (AHCC), a functional food extracted from cultured basidiomycetes, possesses the potential to attenuate adverse events in unresectable pancreas ductal adenocarcinoma (PDAC) patients receiving chemotherapy. Unresectable PDAC patients receiving gemcitabine treatment (GEM) as the first-line chemotherapy were prospectively divided into 2 groups according to AHCC intake (AHCC group, n = 35) or not (control group, n = 40). The patients in the AHCC group ingested 6.0 g of AHCC for 2 mo. Hematological and nonhematological toxicity was compared between the AHCC and control groups. The C-reactive protein (CRP) elevation and albumin decline of the AHCC group were significantly suppressed as compared to the control group during the GEM administration (P = 0.0012, P = 0.0007). Patients in the AHCC group had less frequency of taste disorder caused by GEM (17% vs. 56%, P = 0.0007). Frequency of grade 3 in the modified Glasgow Prognostic Score (mGPS) during chemotherapy was found significantly less in the AHCC group (14%) than the control group (53%, P = 0.0005). AHCC intake can be effective in reducing the adverse events associated with chemotherapy and may contribute to maintaining the QOL of patients with PDAC during GEM administration.

Clinicopathological features and response to platinum-based chemotherapy in pancreatic neuroendocrine carcinoma: A retrospective multicenter study of 70 patients

298

Background: The WHO classified pancreatic neuroendocrine Neoplasms (pNEN) in 2010 as G1, G2, and neuroendocrine carcinoma (NEC). However, pNEC is suspected to include heterogeneous disease entities, but is still not fully studied. We aimed to clarify the clinicopathological and molecular characteristics of NECs. Methods: A total of 100 cases clinical data and pathological slides originally diagnosed as NEC by the WHO in 2010(WHO-NEC) were retrospectively collected from 31 institutes. Expert pathologists were reassessed all cases slide using the designed protocol and reclassified as well differentiated NET (NET-G3), small cell NEC(SCNEC), and large cell NEC(LCNEC) by morphological features. Results: Thirty cases were eliminated mostly because acinar cell carcinoma, NET-G2 and malignant tumor not otherwise specified. Remaining 70 cases were subclassified into 21(30%) NET-G3, 31 (44.3%) SCNEC, 18(25.7%) LCNEC. Comparisons of NET-G3 vs. SCNEC vs. LCNEC revealed the following traits: ENETS stageⅣ: 76%, 81% and 78%; median Ki67 LI: 28.5% (15-53), 85 % (50-100) and 70.0 %(22-90); abnormal Rb expression: 0 %, 59% and 47%; KRAS mutations: 0 %, 48% and 50%; response rates to platinum-based chemotherapy: 0%, 60% and 44.4% ;and median survival(days): 1255, 340 and 196, respectively. When KRAS divided wild (n = 20) and KRAS mutation group (n = 42), response rate to platinum-based chemotherapy was 77% vs 23%.In the same manner, when Rb immune stain divided negative (n = 24) and positive (N = 41), response rate to platinum-based chemotherapy was 80% vs 23.8%. Besides response rate to platinum-based chemotherapy of KRAS mutation(+) and Rb immunopositivity(-) group (n = 7) were 100%, on the other hand, KRAS mutation(-) and Rb immunopositivity(+) group (n = 7) were 18.7%. Conclusions: In this retrospective study, WHO-NEC include 30% NET-G3. NET-G3 are genetically different from SCNEC and LCNEC. As for chemotherapy,Mutated KRAS and/or Rb immunonegativity in tumors with pNEC is associated with response to platinum-based chemotherapy.