Factors Affecting Nonfunctioning Small Pancreatic Neuroendocrine Neoplasms and Proposed New Treatment Strategies.

BACKGROUND & AIMS: Despite previously reported treatment strategies for nonfunctioning small (≤20 mm) pancreatic neuroendocrine neoplasms (pNENs), uncertainties persist. We aimed to evaluate the surgically resected cases of nonfunctioning small pNENs (NF-spNENs) in a large Japanese cohort to elucidate an optimal treatment strategy for NF-spNENs. METHODS: In this Japanese multicenter study, data were retrospectively collected from patients who underwent pancreatectomy between January 1996 and December 2019, were pathologically diagnosed with pNEN, and were treated according to the World Health Organization 2019 classification. Overall, 1490 patients met the eligibility criteria, and 1014 were included in the analysis cohort. RESULTS: In the analysis cohort, 606 patients (59.8%) had NF-spNENs, with 82% classified as grade 1 (NET-G1) and 18% as grade 2 (NET-G2) or higher. The incidence of lymph node metastasis (N1) by grade was significantly higher in NET-G2 (G1: 3.1% vs G2: 15.0%). Independent factors contributing to N1 were NET-G2 or higher and tumor diameter ≥15 mm. The predictive ability of tumor size for N1 was high. Independent factors contributing to recurrence included multiple lesions, NET-G2 or higher, tumor diameter ≥15 mm, and N1. However, the independent factor contributing to survival was tumor grade (NET-G2 or higher). The appropriate timing for surgical resection of NET-G1 and NET-G2 or higher was when tumors were >20 and >10 mm, respectively. For neoplasms with unknown preoperative grades, tumor size >15 mm was considered appropriate. CONCLUSIONS: NF-spNENs are heterogeneous with varying levels of malignancy. Therefore, treatment strategies based on tumor size alone can be unreliable; personalized treatment strategies that consider tumor grading are preferable.

Low skeletal muscle radiodensity is a risk factor for adjuvant chemotherapy discontinuation in colorectal cancer.

BACKGROUND: Previously, we reported SMR (skeletal muscle radiodensity) as a potential prognostic marker for colorectal cancer. However, there have been limited studies on the association between SMR and the continuation of adjuvant chemotherapy in colorectal cancer. METHODS: In this retrospective study, 143 colorectal cancer patients underwent curative surgery and adjuvant chemotherapy using the CAPOX regimen. Patients' SMRs were measured from preoperative CT images and divided into low (bottom quarter) and high (top three quarters) SMR groups. We compared chemotherapy cycles, capecitabine and oxaliplatin doses, and adverse effects in each group. RESULTS: The low SMR group had significantly fewer patients completing adjuvant chemotherapy compared to the high SMR group (44% vs. 68%, P < 0.01). Capecitabine and oxaliplatin doses were also lower in the low SMR group. Incidences of Grade 2 or Grade 3 adverse effects did not differ between groups, but treatment discontinuation due to adverse effects was significantly higher in the low SMR group. Logistic regression analysis revealed Stage III disease (odds ratio 18.09, 95% CI 1.41-231.55) and low SMR (odds ratio 3.26, 95% CI 1.11-9.56) as factors associated with unsuccessful treatment completion. Additionally, a higher proportion of low SMR patients received fewer than 2 cycles of chemotherapy (50% vs. 12%). CONCLUSION: The low SMR group showed higher treatment incompletion rates and received lower drug doses during adjuvant chemotherapy. Low SMR independently contributed to treatment non-completion in colorectal cancer patients.

CAFs-Associated Genes (CAFGs) in Pancreatic Ductal Adenocarcinoma (PDAC) and Novel Therapeutic Strategy.

Pancreatic ductal adenocarcinoma (PDAC) is the most aggressive cancer with striking fibrosis, and its mortality rate is ranked second across human cancers. Cancer-associated fibroblasts (CAFs) play a critical role in PDAC progression, and we reviewed the molecular understanding of PDAC CAFs and novel therapeutic potential at present. CAFs-associated genes (CAFGs) were tentatively classified into three categories by stroma specificity representing stroma/epithelia expression ratios (SE ratios). The recent classification using single cell transcriptome technology clarified that CAFs were composed of myofibroblasts (myCAFs), inflammatory CAFs (iCAFs), and other minor ones (e.g., POSTN-CAFs and antigen presenting CAFs, apCAFs). LRRC15 is a myCAFs marker, and myCAFs depletion by diphtheria toxin induces the rapid accumulation of cytotoxic T lymphocytes (CTLs) and therefore augment PDL1 antibody treatments. This finding proposes that myCAFs may be a critical regulator of tumor immunity in terms of PDAC progression. myCAFs are located in CAFs adjacent to tumor cells, while iCAFs marked by PDPN and/or COL14A1 are distant from tumor cells, where hypoxic and acidic environments being located in iCAFs putatively due to poor blood supply is consistent with HIF1A and GPR68 expressions. iCAFs may be shared with SASP (secretion-associated phenotypes) in senescent CAFs. myCAFs are classically characterized by CAFGs induced by TGFB1, while chemoresistant CAFs with SASP may dependent on IL6 expression and accompanied by STAT3 activation. Recently, it was found that the unique metabolism of CAFs can be targeted to prevent PDAC progression, where PDAC cells utilize glucose, whereas CAFs in turn utilize lactate, which may be epigenetically regulated, mediated by its target genes including CXCR4. In summary, CAFs have unique molecular characteristics, which have been rigorously clarified as novel therapeutic targets of PDAC progression.

Surgical Outcomes of Pancreatectomy with Resection of the Portal Vein and/or Superior Mesenteric Vein and Jejunal Vein for Pancreatic Head Cancer: A Multicenter Study.

OBJECTIVE: The aim of this study was to investigate the safety and survival benefits of portal vein and/or superior mesenteric vein (PV/SMV) resection with jejunal vein resection (JVR) for pancreatic ductal adenocarcinoma (PDAC). SUMMARY BACKGROUND DATA: Few studies have shown the surgical outcome and survival of pancreatic resection with JVR, and treatment strategies for patients with PDAC suspected of jejunal vein (JV) infiltration remain unclear. METHODS: In total, 1260 patients who underwent pancreatectomy with PV/ SMV resection between 2013 and 2016 at 50 facilities were included; treatment outcomes were compared between the PV/SMV group (PV/ SMV resection without JVR; n = 824), PV/SMV-J1 V group (PV/SMV resection with first jejunal vein resection; n = 394), and PV/SMV-J2,3 V group (PV/SMV resection with second jejunal vein or later branch resection; n = 42). RESULTS: Postoperative complications and mortality did not differ between the three groups. The postoperative complication rate associated with PV/ SMV reconstruction was 11.9% in PV/SMV group, 8.6% in PV/SMV-J1 V group, and 7.1% in PV/SMV-J2,3V group; there were no significant differences among the three groups. Overall survival did not differ between PV/SMV and PV/SMV-J1 V groups (median survival; 29.2 vs 30.9 months, P = 0.60). Although PV/SMV-J2,3 V group had significantly shorter survival than PV/SMV group who underwent upfront surgery ( P = 0.05), no significant differences in overall survival of patients who received preoperative therapy. Multivariate survival analysis revealed that adjuvant therapy and R0 resection were independent prognostic factors in all groups. CONCLUSION: PV/SMV resection with JVR can be safely performed and may provide satisfactory overall survival with the pre-and postoperative adjuvant therapy.

Early administration of postoperative BCAA-enriched PPN may improve lean body mass loss in gastric cancer patients undergoing gastrectomy.

BACKGROUND: It has been reported that weight loss or lean body mass (LBM) loss after gastrectomy for gastric cancer is associated with prognosis and nutritional support alone is insufficient to prevent LBM loss. Branched-chain amino acids (BCAA) play an important role in muscle catabolism, however their clinical effects on suppression of LBM loss in gastric cancer patients undergoing gastrectomy remains elusive. In this current study, we investigated the effect of our original PPN regimen including BCAA (designated to BCAA-regimen) on LBM loss. METHODS: We conducted a randomized controlled trial (RCT) at a single institution where patients undergoing gastrectomy were assigned to either receive a five-day early postoperative course of the BCAA-regimen (BCAA group) or conventional nutrition. The primary endpoint was the % reduction in LBM at postoperative day 7. The secondary endpoints included the % reduction in LBM at 1 and 3 months postsurgery. RESULTS: At postoperative day 7, LBM loss in the BCAA group tended to be lower than in the control group (0.16% vs. 1.7%, respectively; P = 0.21), while at 1 month postsurgery, LBM loss in the BCAA group was significantly different to that of the control group (- 0.3% vs. 4.5%, respectively; P = 0.04). At 3 months postgastrectomy, however, LBM loss was similar between the BCAA and the control groups. CONCLUSION: Our RCT clinical trial clarified that early administration of the postoperative BCAA regimen improved LBM loss at 1 month after surgery in gastric cancer patients undergoing gastrectomy.

Population Pharmacokinetic-Pharmacodynamic Target Attainment Analysis of Flomoxef in the Serum and Liver Tissue of Patients Undergoing Hepatic Resection.

The purpose of this study was to investigate the population pharmacokinetics of prophylactic flomoxef based on serum and liver tissue concentrations and to demonstrate a pharmacodynamic target concentration in the serum and liver tissue exceeding the MIC in order to design an effective dosing regimen. Serum samples (n = 210) and liver tissue samples (n = 29) from 43 individuals were analyzed using a nonlinear mixed-effects model. The pharmacodynamics index target value was regarded as the probability of maintaining flomoxef serum trough and liver tissue concentrations exceeding the MIC90 values, 0.5 mg/L and 1.0 mg/L, for Escherichia coli and methicillin-susceptible Staphylococcus aureus, respectively. The final population pharmacokinetic model was a two-compartment model with linear elimination. Creatinine clearance (CLCR) was identified as a significant covariate influencing total clearance when CLCR was less than 60 mL/min. The probability of achieving concentrations in the serum and liver tissue exceeding the MIC90 for E. coli or methicillin-susceptible S. aureus for a 1 g bolus dose was above 90% at 2 h after the initial dose. Our findings suggest that population pharmacokinetic parameters are helpful for evaluating flomoxef pharmacokinetics and determining intraoperative flomoxef redosing intervals.

Pancreas-contactless gastrectomy for gastric cancer prevents postoperative inflammation.

BACKGROUND: Pancreas-related complications after laparoscopic gastrectomy (LG) for gastric cancer can be fatal. We developed a gastrectomy procedure with no pancreas contact to prevent such complications and herein report the surgical outcomes. METHODS: We retrospectively reviewed 182 consecutive patients with gastric cancer who underwent LG at Kitasato University Hospital from January 2017 to January 2020. These patients were divided into a pancreas-contact group (C group) and pancreas-contactless group (CL group) for comparison of postoperative complications, and inflammatory parameters such as body temperature (BT) and C-reactive protein (CRP). RESULTS: Postoperative complications of CDc grade ≧ IIIa were significantly fewer in the CL group than in the C group [0/76 (0%) vs. 6/106 (5.7%), P = 0.035]. The median drain amylase (drain-AMY) on postoperative day 1 (POD1) was significantly lower in the CL group than in the C group (641 vs. 1162 IU/L, P = 0.02), as was BT at POD1 (37.4 °C vs. 37.7 °C, P = 0.04), the patient group with a BT above 37.5 °C at POD3 [5/76 (6.5%) vs. 18/106 (17%), P = 0.037], and those showing a CRP above 20.0 mg/dL at POD3 [5/76 (6.5%) vs. 20/106 (19%), P = 0.018]. CONCLUSIONS: Our technique to prevent pancreas contact during supra-pancreatic lymph node dissection during LG could minimize the inflammatory response and prevent further postoperative complications. Further large-scale, prospective studies are now required.

[A Case of Stage â £ Pancreatic Head Cancer with Aortic Lymph Node Metastasis Treated with 40 Courses of mFOLFIRINOX Therapy after Surgery and Maintaining PR].

The patient was a male in his 60s who presented with obstructive jaundice and was diagnosed with pancreatic head cancer. He was referred to the Department of Surgery 2 months later due to prolonged jaundice and immediately underwent pylorus-preserving pancreatoduodenectomy with the diagnosis of resectable pancreatic cancer. Pathology showed pN1b (14/37), but 16b1 interaorticocaval was 0/1. The patient was then diagnosed with Stage ⅡB, R0. After completion of adjuvant chemotherapy with S-1, 1 year after surgery, CA19-9 was reelevated and PET/CT-positive enlarged lateroaortic lymph nodes and multiple nodules in both lungs were observed. The lymph nodes were also seen on preoperative CT, and the preoperative diagnosis was Stage Ⅳ. After insertion of an implantable central venous port, mFOLFIRINOX therapy was initiated. The patient had an anaphylactic reaction after 7 courses of L-OHP, and the treatment was continued without L-OHP. After 40 courses of mFOLFIRINOX therapy, the aortic lymph nodes reduced in size, PET results were negative, and the pulmonary nodules partially resolved. We report a case of a patient with Stage Ⅳ pancreatic head cancer who maintained PR for more than 1 year and 7 months after the initiation of mFOLFIRINOX therapy and survived for more than 2 years and 10 months since the initial diagnosis.

Prospective study to validate the clinical utility of DNA diagnosis of peritoneal fluid cytology test in gastric cancer.

The clinical efficacy of DNA cytology test (CY) in gastric cancer (GC) has been retrospectively proposed using cancer-specific methylation of cysteine dioxygenase type 1 (CDO1). We confirmed the clinical utility of DNA CY in a prospective cohort. Four hundred GC samples were prospectively collected for washing cytology (UMIN000026191), and detection of the DNA methylation of CDO1 was assessed by quantitative methylation-specific PCR in the sediments. Endpoint was defined as the match rate between conventional CY1 and DNA CY1 (diagnostic sensitivity), and the DNA CY0 rate (diagnostic specificity) in pStage IA. DNA CY1 was detected in 45 cases (12.5%), while CY1 was seen in 31 cases (8.6%) of 361 chemotherapy-naïve samples, where the sensitivity and specificity of the DNA CY in the peritoneal solutions were 74.2% and 96.5%, respectively. The DNA CY was positive for 3.5/0/4.9/11.4/58.8% in pStage IA/IB/II/III/IV, respectively (P < .01). In the multivariate analysis, DNA CY1 was independently correlated with pathological tumor depth (pT) (P = .0012), female gender (P = .0099), CY1 (P = .0135), P1 (P = .019), and carcinoembryonic antigen (CEA) (P = .036). The combination of DNA CY1 and P factor nearly all covered the potential peritoneal dissemination (P1 and/or CY1 and/or DNA CY1) (58/61:95.1%). DNA CY1 had a significantly poorer prognosis than DNA CY0 in GC patients (P < .0001). DNA CY1 detected by CDO1 promoter DNA methylation has a great value to detect minimal residual disease of the peritoneum in GC clinics, representing poor prognosis as a novel single DNA marker.

EP3 signaling in dendritic cells promotes liver repair by inducing IL-13-mediated macrophage differentiation in mice.

Macrophage plasticity is essential for liver wound healing; however, the mechanisms underlying macrophage phenotype switching are largely unknown. Dendritic cells (DCs) are critical initiators of innate immune responses; as such, they orchestrate inflammation following hepatic injury. Here, we subjected EP3-deficient (Ptger3-/- ) and wild-type (WT) mice to hepatic ischemia-reperfusion (I/R) and demonstrate that signaling via the prostaglandin E (PGE) receptor EP3 in DCs regulates macrophage plasticity during liver repair. Compared with WT mice, Ptger3-/- mice showed delayed liver repair accompanied by reduced expression of hepatic growth factors and accumulation of Ly6Clow reparative macrophages and monocyte-derived DCs (moDCs). MoDCs were recruited to the boundary between damaged and undamaged liver tissue in an EP3-dependent manner. Adoptive transfer of moDCs from Ptger3-/- mice resulted in impaired repair, along with increased numbers of Ly6Chigh inflammatory macrophages. Bone marrow macrophages (BMMs) up-regulated expression of genes related to a reparative macrophage phenotype when co-cultured with moDCs; this phenomenon was dependent on EP3 signaling. In the presence of an EP3 agonist, interleukin (IL)-13 derived from moDCs drove BMMs to increase expression of genes characteristic of a reparative macrophage phenotype. The results suggest that EP3 signaling in moDCs facilitates liver repair by inducing IL-13-mediated switching of macrophage phenotype from pro-inflammatory to pro-reparative.

Lymphangiogenesis and accumulation of reparative macrophages contribute to liver repair after hepatic ischemia-reperfusion injury.

Hepatic tissue repair plays a critical role in determining the outcome of hepatic ischemia-reperfusion (I/R) injury. Hepatic lymphatics participate in the clearance of dead tissues and contribute to the reparative process after acute hepatic injury; however, it remains unknown whether lymphangiogenesis in response to hepatic inflammation is involved in liver repair. Herein, we determined if hepatic lymphangiogenesis improves liver repair after hepatic I/R injury. Using a mouse model of hepatic I/R injury, we investigated hepatic lymphatic structure, growth, and function in injured murine livers. Hepatic I/R injury enhanced lymphangiogenesis around the portal tract and this was associated with increased expression of pro-lymphangiogenic growth factors including vascular endothelial growth factor (VEGF)-C and VEGF-D. Recombinant VEGF-D treatment facilitated liver repair in association with the expansion of lymphatic vessels and increased expression of genes related to the reparative macrophage phenotype. Treatment with a VEGF receptor 3 (VEGFR3) inhibitor suppressed liver repair, lymphangiogenesis, drainage function, and accumulation of VEGFR3-expressing reparative macrophages. VEGF-C and VEGF-D upregulated expression of genes related to lymphangiogenic factors and the reparative macrophage phenotype in cultured macrophages. These results suggest that activation of VEGFR3 signaling increases lymphangiogenesis and the number of reparative macrophages, both of which play roles in liver repair. Expanded lymphatics and induction of reparative macrophage accumulation may be therapeutic targets to enhance liver repair after hepatic injury.

Promoter DNA Hypermethylation of the Cysteine Dioxygenase 1 (CDO1) Gene in Intraductal Papillary Mucinous Neoplasm (IPMN).

BACKGROUND: Intraductal papillary mucinous neoplasm (IPMN) involves adenoma (IPMA), a precancerous lesion, cancer (IPMC) including high-grade dysplasia (HGD), and invasive carcinoma (IC). DNA markers of IPMN are required for detection of invasive disease, and cysteine dioxygenase 1 (CDO1) gene promoter hypermethylation is a potential candidate. However, it has never been investigated in the context of IPMN. PATIENTS AND METHODS: A total of 107 IPMN tumor tissues, including 41 IPMC and 66 IPMA, were studied. CDO1 promoter methylation was quantified using TaqMan quantitative methylation-specific polymerase chain reaction (qMSP) in patients with IPMN and other pancreatic cystic disorders after pancreatectomy. RESULTS: The methylation values (TaqMeth Vs) of CDO1 increased when noncancerous pancreas tissues were compared with IPMA and HGD (p < 0.0001). Among IPMC, the TaqMeth Vs in IC were not significantly higher than in HGD. The TaqMeth Vs of the solid tumors were higher than those of the cystic tumors (p = 0.0016), which were in turn higher than the corresponding noncancerous tissues (p < 0.0001). Prognostic analysis revealed that high TaqMeth Vs (≥ 14.1) resulted in a poorer prognosis than low TaqMeth Vs (< 14.1) (p < 0.0001). In other pancreatic cystic diseases, only malignant mucinous cystic neoplasm showed DNA hypermethylation of its promoter. A pilot study in pancreatic juice confirmed methylation in all IPMN samples but not in benign pancreatic diseases (p = 0.0277). CONCLUSIONS: CDO1 promoter hypermethylation is extremely specific to IPMN and may accumulate with IPMN tumor progression during the adenoma-carcinoma sequence. It might be a promising candidate as a diagnostic marker of pancreatic cystic diseases.

Neoadjuvant chemotherapy plus surgery for high-risk advanced gastric cancer: long-term results of KDOG1001 trial.

PURPOSE: The purpose of this study is to evaluate the long-term survival outcomes of KDOG1001 trial after a minimum follow-up of 3 years. METHODS: Patients with bulky N2 lymph nodes, linitis plastica (type 4), or large ulcero-invasive-type tumors (type 3) received up to four 28-day cycles of DCS neoadjuvant chemotherapy (docetaxel at 40 mg/m2, cisplatin at 60 mg/m2 on day 1, and S-1 at 40 mg/m2 twice daily for 2 weeks) followed by gastrectomy with D2 lymphadenectomy plus adjuvant S-1 therapy for 1 year. The final preplanned analysis of long-term outcomes including overall survival and relapse-free survival was conducted after minimum follow-up of 3 years. This trial is registered with the University Hospital Medical Information Network Clinical Trials Registry, number UMIN 000003642, and has been completed. RESULTS: From May 2010 through January 2017, 40 patients were enrolled. All included patients underwent neoadjuvant chemotherapy with DCS followed by gastrectomy with D2 lymphadenectomy, and 32 (80%) completed adjuvant S-1 therapy for 1 year. After a median follow-up for surviving patients of 68 months at the last follow-up in January 2020, 3-year overall survival rate was 77.5% (95% confidence interval 62.1-87.9%), while 3-year relapse-free survival rate was 62.5% (95% confidence interval 46.8-76.0%). CONCLUSION: Neoadjuvant chemotherapy with 4 cycles of DCS followed by D2 gastrectomy plus adjuvant S-1 was associated with relatively good long-term oncologic outcomes for patients with the high-risk gastric cancer.

Diagnostic potential of hypermethylation of the cysteine dioxygenase 1 gene (CDO1) promoter DNA in pancreatic cancer.

DNA markers for pancreatic ductal adenocarcinoma (PDAC) are urgently needed for detection of minimally invasive disease. The epigenetic relevance of the cysteine dioxygenase 1 gene (CDO1) has been never investigated in PDAC. Three studies, including cellular experiments, tissue validation, and pilot testing for pancreatic cytology, were carried out. Promoter DNA methylation value (MV) of CDO1 was quantified by quantitative methylation-specific PCR. CDO1 expression was consistent with its promoter DNA methylation in 7 PDAC cell lines. In 160 retrospectively collected primary PDAC tumor tissues, MV was significantly higher compared to the corresponding noncancerous pancreas (area under the receiver operating characteristic curve [AUC] = 0.97, P < .0001), and CDO1 hypermethylation was highly specific to PDAC tumor tissues. CDO1 hypermethylation group (MV over 19) was significantly associated with diverse prognostic factors in PDAC. Surprisingly, it was significantly higher in prospectively collected PDAC cytology samples (n = 37), including both pancreatic juice (n = 12) and endoscopic ultrasound-fine needle aspiration (EUS-FNA) cytology (n = 25) compared to pancreatic benign diseases (AUC = 0.96, P < .0001). Detection of PDAC was confirmed by DNA testing in 35 of 37 patients (95% sensitivity); thus, it was more sensitive than cytology (33%) or EUS-FNA cytology (88%). Promoter DNA methylation of CDO1 is extremely specific for PDAC tumors, and accumulates with PDAC tumor progression. It could be a definitive diagnostic marker of PDAC in pancreatic juice or EUS-FNA cytology.

[A Patient Who Underwent Resection of Liver Metastases after Receiving Systemic Chemotherapy for Advanced Rectal Cancer and Multiple Liver Metastases].

The patient was a 52-year-old man who had a positive fecal occult-blood test on a medical check-upi n April 2015 and was referred to our hospital in June. Detailed preoperative examinations resulted in a diagnosis of cancer of the lower rectum, multiple liver metastases, and clinical Stage IV . A biopsy showed moderately differentiated tubular adenocarcinoma. All-RAS was wild type, and the patient was asymptomatic. Unresectable advanced rectal cancer was diagnosed, and the patient was scheduled to receive systemic chemotherapy. The patient received a total of 16 courses of combination chemotherapy with 5- fluorouracil, Leucovorin, and oxaliplatin(FOLFOX)plus panitumumab, starting in October 2015. In July 2016, Colonoscopy showed scar findings at the site of the primary rectal cancer lesion. A biopsy revealed no cancer cells. It was difficult to identify the primary lesion on computed tomography, and there was no evidence of clinically significant lymphadenopathy. Positronemission tomography and computed tomography showed shrinkage of the liver metastases, with no accumulation of tracer in the primary lesion or lymph nodes. The primary lesion had a clinical complete response(CR), and the metastatic lesions had a clinical partial response(PR). In October 2016, laparoscopic partial hepatectomy was performed to treat the liver metastases. Histologic examination showed that the liver metastases were from rectal cancer. It is currently under observation.

[Conversion Surgery for Initially Unresectable Locally Advanced Pancreatic Cancer Following Gemcitabine plus Nab-Paclitaxel - A Case Report].

We report a case of unresectable locally advanced pancreatic cancer successfully resected after gemcitabine(GEM)plus nab-paclitaxel(PTX)treatment. A 68-year-old man was referred to our institution with jaundice. We diagnosed pancreatic head cancer using computed tomography(CT)and endoscopic retrograde cholangiopancreatography. We initially diagnosed it as locally advanced unresectable pancreatic cancer because of extensive invasion to the portal vein. GEM plus nab- PTX was administered to the patient as systemic chemotherapy. After 9 courses of chemotherapy, a CT scan revealed that the tumor had significantly reduced in size and range of portal vein invasion. Therefore, we performed pancreaticoduodenectomy with resection of the portal vein and achieved R0 resection. Currently, the patient is alive without recurrence. Therefore, conversion surgery after treatment with GEM plus nab-PTX chemotherapy for unresectable pancreatic cancer should be considered.

CAF-associated genes putatively representing distinct prognosis by in silico landscape of stromal components of colon cancer.

Comprehensive understanding prognostic relevance of distinct tumor microenvironment (TME) remained elusive in colon cancer. In this study, we performed in silico analysis of the stromal components of primary colon cancer, with a focus on the markers of cancer-associated fibroblasts (CAF) and tumor-associated endothelia (TAE), as well as immunological infiltrates like tumor-associated myeloid cells (TAMC) and cytotoxic T lymphocytes (CTL). The relevant CAF-associated genes (CAFG)(representing R index = 0.9 or beyond with SPARC) were selected based on stroma specificity (cancer stroma/epithelia, cS/E = 10 or beyond) and expression amounts, which were largely exhibited negative prognostic impacts. CAFG were partially shared with TAE-associated genes (TAEG)(PLAT, ANXA1, and PTRF) and TAMC-associated genes (TAMCG)(NNMT), but not with CTL-associated genes (CTLG). Intriguingly, CAFG were prognostically subclassified in order of fibrosis (representing COL5A2, COL5A1, and COL12A1) followed by exclusive TAEG and TAMCG. Prognosis was independently stratified by CD8A, a CTL marker, in the context of low expression of the strongest negative prognostic CAFG, COL8A1. CTLG were comprehensively identified as IFNG, B2M, and TLR4, in the group of low S/E, representing good prognosis. Our current in silico analysis of the micro-dissected stromal gene signatures with prognostic relevance clarified comprehensive understanding of clinical features of the TME and provides deep insights of the landscape.

A multi-institutional study designed by members of Tokyo Guidelines (TG) Core Meeting to elucidate the clinical characteristics and pathogenesis of acute cholangitis after bilioenteric anastomosis and biliary stent insertion with a focus on biliary obstruction: Role of transient hepatic attenuation difference (THAD) and pneumobilia in improving TG diagnostic performance.

BACKGROUND/PURPOSE: The aim of this study was to clarify the clinical characteristics of acute cholangitis (AC) after bilioenteric anastomosis and stent-related AC in a multi-institutional retrospective study, and validate the TG18 diagnostic performance for various type of cholangitis. METHODS: We retrospectively reviewed 1079 AC patients during 2020, at 16 Tokyo Guidelines 18 (TG 18) Core Meeting institutions. Of these, the post-biliary reconstruction associated AC (PBR-AC), stent-associated AC (S-AC) and common AC (C-AC) were 228, 307, and 544, respectively. The characteristics of each AC were compared, and the TG18 diagnostic performance of each was evaluated. RESULTS: The PBR-AC group showed significantly milder biliary stasis compared to the C-AC group. Using TG18 criteria, definitive diagnosis rate in the PBR-AC group was significantly lower than that in the C-AC group (59.6% vs. 79.6%, p < .001) because of significantly lower prevalence of TG 18 imaging findings and milder bile stasis. In the S-AC group, the bile stasis was also milder, but definitive-diagnostic rate was significantly higher (95.1%) compared to the C-AC group. The incidence of transient hepatic attenuation difference (THAD) and pneumobilia were more frequent in PBR-AC than that in C-AC. The definitive-diagnostic rate of PBR-AC (59.6%-78.1%) and total cohort (79.6%-85.3%) were significantly improved when newly adding these items to TG18 diagnostic imaging findings. CONCLUSIONS: The diagnostic rate of PBR-AC using TG18 is low, but adding THAD and pneumobilia to TG imaging criteria may improve TG diagnostic performance.

Short-term outcomes of robot-assisted versus conventional laparoscopic surgery for mid and low rectal cancer after neoadjuvant chemoradiotherapy: a propensity score-matched analysis.

The benefits of robot-assisted laparoscopic surgery (RALS) for rectal cancer remain controversial. Only a few studies have evaluated the safety and feasibility of RALS following neoadjuvant chemoradiotherapy (NCRT). This study aimed to compare the short-term outcomes of RALS versus conventional laparoscopic surgery (CLS) after NCRT for rectal cancer. Propensity score matching of 111 consecutive patients who underwent RALS or CLS after NCRT for rectal adenocarcinoma between February 2014 and February 2022 was performed. Among them, 60 matched patients were enrolled and their short-term outcomes were compared. Although operative time, conversion rate to open laparotomy and blood loss were comparable, the incidence of postoperative complications, including anastomotic leakage, was significantly lower, urinary retention tended to be lower, and the days to soft diet intake and postoperative hospital stay were significantly shorter in the RALS than the CLS group. No postoperative mortality was observed in either group, and there were no significant differences in terms of resection margins and number of lymph nodes dissected. RALS after NCRT for rectal cancer is safe and technically feasible, and has acceptable short-term outcomes. Further studies are required for validation of the long-term oncological outcomes.

Less demand on stem cell marker-positive cancer cells may characterize metastasis of colon cancer.

BACKGROUND: CD44 and CD133 are stem cell markers in colorectal cancer (CRC). CD44 has distinctive isoforms with different oncological properties like total CD44 (CD44T) and variant CD44 (CD44V). Clinical significance of such markers remains elusive. METHODS: Sixty colon cancer were examined for CD44T/CD44V and CD133 at mRNA level in a quantitative PCR, and clarified for their association with clinicopathological factors. RESULTS: (1) Both CD44T and CD44V showed higher expression in primary colon tumors than in non-cancerous mucosas (p<0.0001), while CD133 was expressed even in non-cancerous mucosa and rather decreased in the tumors (p = 0.048). (2) CD44V expression was significantly associated with CD44T expression (R = 0.62, p<0.0001), while they were not correlated to CD133 at all in the primary tumors. (3) CD44V/CD44T expressions were significantly higher in right colon cancer than in left colon cancer (p = 0.035/p = 0.012, respectively), while CD133 expression were not (p = 0.20). (4) In primary tumors, unexpectedly, CD44V/CD44T/CD133 mRNA expressions were not correlated with aggressive phenotypes, but CD44V/CD44T rather significantly with less aggressive lymph node metastasis/distant metastasis (p = 0.040/p = 0.039, respectively). Moreover, both CD44V and CD133 expressions were significantly decreased in liver metastasis as compared to primary tumors (p = 0.0005 and p = 0.0006, respectively). CONCLUSION: Our transcript expression analysis of cancer stem cell markers did not conclude that their expression could represent aggressive phenotypes of primary and metastatic tumors, and rather represented less demand on stem cell marker-positive cancer cells.