The morbidity rate after pancreaticoduodenectomy remains high. The objectives of this retrospective cohort study were to clarify the risk factors associated with serious morbidity (Clavien–Dindo classification grades IV–V), and create complication risk calculators using the Japanese National Clinical Database. Between 2011 and 2012, data from 17,564 patients who underwent pancreaticoduodenectomy at 1,311 institutions in Japan were recorded in this database. The morbidity rate and associated risk factors were analyzed. The overall and serious morbidity rates were 41.6% and 4.5%, respectively. A pancreatic fistula (PF) with an International Study Group of Pancreatic Fistula (ISGPF) grade C was significantly associated with serious morbidity (P < 0.001). Twenty-one variables were considered statistically significant predictors of serious complications, and 15 of them overlapped with those of a PF with ISGPF grade C. The predictors included age, sex, obesity, functional status, smoking status, the presence of a comorbidity, non-pancreatic cancer, combined vascular resection, and several abnormal laboratory results. C-indices of the risk models for serious morbidity and grade C PF were 0.708 and 0.700, respectively. Preventing a PF grade C is important for decreasing the serious morbidity rate and these risk calculations contribute to adequate patient selection.

Objective: This randomized phase II/III study evaluated the superiority of neoadjuvant therapy with gemcitabine plus S-1 over upfront surgery for patients with resectable pancreatic ductal adenocarcinoma (PDAC). Background: PDAC is a leading cause of cancer mortality that urgently requires better treatment. Methods: Patients with resectable PDAC (without arterial abutment) were randomly assigned to upfront surgery or neoadjuvant chemotherapy with gemcitabine (1000 mg/m ² days 1 and 8) and S-1 (40–60 mg orally twice daily, days 1–14 every 3 wk for 2 cycles). Phase II and III primary endpoints were resection rate and overall survival, respectively. UMIN Clinical Trials Registry number: UMIN000009634. Results: Patients (n=364) were enrolled and randomly allocated to upfront surgery (UPS; n=182) or neoadjuvant gemcitabine plus S-1 (NAC-GS; n=182). Patient demographics and tumor characteristics were balanced between groups. Median overall survival in the UPS and NAC-GS groups was 26.6 (95% CI: 21.5, 31.5) and 37.0 (95% CI: 28.6, 43.3) months, respectively. The hazard ratio for mortality in the NAC-GS group compared with the UPS group was 0.73 (95% CI: 0.56, 0.95; P =0.018). Median relapse-free survival in the UPS and NAC-GS groups was 11.3 (95% CI: 9.41, 13.5) and 14.3 (95% CI: 11.7, 17.0) months, respectively. The hazard ratio for relapse in the NAC-GS group compared with the UPS group was 0.77 (95% CI: 0.61, 0.98; P =0.030). Conclusions: The Prep-02/JSAP05 trial results showed that neoadjuvant chemotherapy with gemcitabine plus S-1 significantly extends survival compared with upfront surgery in patients with resectable PDAC.

Pancreatic ductal adenocarcinoma (PDAC) is among the cancers with the poorest prognoses due to its highly malignant features. BTB and CNC homology 1 (BACH1) has been implicated in RAS-driven tumor formation. We focused on the role of BACH1 in PDAC, more than 90% of which have KRAS mutation. Knockdown of BACH1 in PDAC cell lines reduced cell migration and invasion, in part, by increasing E-cadherin expression, whereas its overexpression showed opposite effects. BACH1 directly repressed the expression of FOXA1 that is known to activate the expression of CDH1 encoding E-cadherin and to inhibit epithelial-to-mesenchymal transition. BACH1 also directly repressed the expression of genes important for epithelial cell adhesion including CLDN3 and CLDN4. In a mouse orthotopic implantation model, BACH1 was required for the high metastatic ability of AsPC-1 cells. IHC analysis of clinical specimens with a newly developed anti-BACH1 mAb revealed that high expression of BACH1 is a poor prognostic factor. These results suggest that the gene regulatory network of BACH1 and downstream genes including CDH1 contribute to the malignant features of PDAC by regulating epithelial-to-mesenchymal transition.Significance: Greater understanding of the gene regulatory network involved in epithelial-to-mesenchymal transition of pancreatic cancer cells will provide novel therapeutic targets and diagnostic markers.

In 2023, the Japan Pancreas Society (JPS) published the new eighth edition of the Japanese classification of pancreatic carcinoma. We present here an excerpted version in English, based on the latest edition. The major changes in this revision are as follows: In the eighth edition of the Union for International Cancer Control (UICC), the T category was changed to be based on tumor size; however, the eighth edition of the Japanese classification retains the previous T category based on local invasion factors. Lymph nodes have been renamed, and regional lymph nodes have been defined by location. Peritoneal cytology, which was not previously included in distant metastasis (M), has now been included in the M category. Moreover, significant additions have been made regarding the pathological diagnosis of endoscopic ultrasound‐guided fine‐needle aspiration biopsy (EUS‐FNAB) and criteria for histological assessment of the effects after chemotherapy and radiation therapy. Although this classification is aimed at carcinoma originating in the pancreas, not in the bile duct or duodenum, if the differentiation of the primary organ is difficult, this classification should be applied. It is also desirable to describe tumors other than carcinoma and metastatic tumors to the pancreas in accordance with this classification.