Genomically Stable Gastric Cancer Characterized by Hypomethylation in Wnt Signal Cascade

INTRODUCTION

Gastric cancer is divided into four subtypes by their molecular features linked with genetic alterations, e.g., Epstein-Barr virus (EBV), microsatellite instability-high (MSI-high), chromosomal instability (CIN), and genomically stable (GS), called as TCGA classification. In this study, we tried to clarify the epigenetic features of the four GC subtypes according to aberrant methylation status in 23 loci.

METHODS

A total of 98 gastric cancers and their normal gastric mucosa samples were included in this study. We divided gastric cancers into TCGA subtypes which were determined in line with MSI-high, EBV, CIN, to GS by their molecular features. The 13 loci of polymorphic microsatellite sequences were used to determine loss of heterogeneity for the detection of CIN. The MSI status was determined by three mononucleotide repeat markers. Infection of EBV was determined by recovering EBV BNRF1 sequence from genomic DNA collected from gastric cancers. Methylation status of 23 loci was investigated by the combined bisulfite restriction analysis. Status of other findings, e.g., KRAS mutations, HER2 expression status, and infection of helicobacter pylori were confirmed.

RESULTS

Gastric cancers were divided into MSI (13%), EBV (7%), CIN (53%), and GS (27%). By histological classification, poorly differentiated adenocarcinoma was more in tumors categorized in MSI-high, and GS and signet-ring cell carcinoma (sig) were more in GS. Among the 23 loci investigated their methylation status, 18 loci were significantly hypermethylated in caner tissues. An unsupervised clustering divided gastric cancers into two clusters and revealed that most GS tumors clustered together in a cluster that exhibited lower methylation levels, distinct from the other subtypes. The inter-variable clustering revealed that a cluster contained the three loci (SFRP2-region 1/2 and APC) belonging to the Wnt signal cascade (Wnt-associated loci). The mean methylation score of Wnt-associated loci was the lowest in GS tumors (MSI-high: 2.7 [95% confidence interval, 2.3-2.9]; EBV: 2.1 [1.2-3.1]; CIN: 2.4 [2.2-2.7]; GS: 1.3 [0.8-0.7]). In contrast, the mean methylation score of the other 15 loci was significantly higher in MSI-high, while that in GS was as same as that in EBV or CIN (MSI-high: 10.4 [8.3-12.4]; EBV: 5.7 [1.7-9.7]; CIN: 4.4 [3.6-5.1]; GS: 3.4 [2.2-4.6]). Additionally, the lower methylation score of Wnt-associated loci was observed only in sig tumors.

CONCLUSIONS

GS subtype tumors have the potential to possess distinct signatures in DNA hypomethylation profiles in Wnt signaling pathway, especially in sig.

Robotic Spleen-Preserving Distal Pancreatectomy with Preservation of Splenic Vessels Using the Gastrohepatic Ligament Approach: The Superior Window Approach in the Kimura Technique

Minimally invasive spleen-preserving distal pancreatectomy (SPDP) is technically challenging, and only a few reports have described surgical approaches for minimally invasive SPDP. This report demonstrates our novel gastrohepatic ligament approach in robotic SPDP with preservation of the splenic vessels (the superior window approach in the Kimura technique). Our gastrohepatic ligament approach for robotic SPDP included four steps. First, the gastrohepatic ligament was divided extensively, and the pancreas was confirmed (step 1). In this step, we did not lift the stomach, nor did we divide the gastrocolic ligament. Next, the superior and inferior borders of the pancreas were dissected, and the tunneling of the pancreas on the superior mesenteric vein was performed (step 2). Following the division of the pancreas (step 3), the pancreatic body and tail were dissected from the medial to the lateral side with preservation of the splenic vessels (step 4). Using this approach, the pancreas can be directly accessed via the gastrohepatic ligament route and dissected without division of the gastrocolic ligament or retraction of the stomach. The present approach for robotic SPDP preserves splenic vessels, facilitating easy access to the pancreas with minimal dissection, and may be optional in selected patients, including those with low body mass index.

Feasibility of local therapy for recurrent pancreatic cancer

BACKGROUND

Despite advances in perioperative management, recurrence after curative pancreatectomy is a critical issue in the treatment of pancreatic ductal adenocarcinoma (PDAC). The significance of local therapy for recurrent PDAC remains unclear.

METHODS

We reviewed the medical records of patients with PDAC who underwent curative resection at our institution between January 2009 and December 2019. We examined the patterns of relapse and assessed the clinical outcomes of patients with recurrence who underwent local therapy, including surgical resection, radiotherapy, and radiofrequency ablation.

RESULTS

A total of 246 patients with PDAC who underwent R0 or R1 resection were included in this study. The 3-year overall survival (OS) rate was 39.8%, and the 1-year recurrence-free survival rate was 51.2% for the entire population. Recurrence was observed in 172/246 (69.9%) patients, including multiple site recurrences in 50, liver metastasis in 41, locoregional recurrence in 34, and peritoneal dissemination in 27. Of the 172 patients, treatment was administered in 137 (79.7%), and 16 received local therapy, including surgical resection (n = 13), radiotherapy (n = 5), and RFA (n = 1). PS-matched analysis revealed that patients with recurrence who were treated with chemotherapy combined with local therapy showed better post-recurrence survival rates than those treated with chemotherapy alone (P = 0.016). Detailed clinical courses of these patients are presented in the main manuscript.

CONCLUSIONS

Our results suggest that a multimodal approach may improve the clinical outcomes of patients with recurrent PDAC.

RNA editing facilitates the enhanced production of neoantigens during the simultaneous administration of oxaliplatin and radiotherapy in colorectal cancer

Most cases of colorectal cancers (CRCs) are microsatellite stable (MSS), which frequently demonstrate lower response rates to immune checkpoint inhibitors (ICIs). RNA editing produces neoantigens by altering amino acid sequences. In this study, RNA editing was induced artificially by chemoradiation therapy (CRT) to generate neoantigens in MSS CRCs. Altogether, 543 CRC specimens were systematically analyzed, and the expression pattern of ADAR1 was investigated. In vitro and in vivo experiments were also performed. The RNA editing enzyme ADAR1 was upregulated in microsatellite instability-high CRCs, leading to their high affinity for ICIs. Although ADAR1 expression was low in MSS CRC, CRT including oxaliplatin (OX) treatment upregulated RNA editing levels by inducing ADAR1. Immunohistochemistry analyses showed the upregulation of ADAR1 in patients with CRC treated with CAPOX (capecitabine + OX) radiation therapy relative to ADAR1 expression in patients with CRC treated only by surgery (p < 0.001). Compared with other regimens, CRT with OX effectively induced RNA editing in MSS CRC cell lines (HT29 and Caco2, p < 0.001) via the induction of type 1 interferon-triggered ADAR1 expression. CRT with OX promoted the RNA editing of cyclin I, a neoantigen candidate. Neoantigens can be artificially induced by RNA editing via an OX-CRT regimen. CRT can promote proteomic diversity via RNA editing.

Impact of Amino Acids Nutrition Following Gastrectomy in Gastric Cancer Patients

BACKGROUND/AIM

Postoperative body weight loss (BWL) and skeletal muscle loss (SML) after gastrectomy are associated with a decline in quality of life and worse longterm prognosis in gastric cancer (GC) patients. This study aimed to evaluate the efficacy of amino acids nutrition on BWL and SML in the early period following gastrectomy.

PATIENTS AND METHODS

The parameters of body composition were measured by bioelectrical impedance analysis in the patients undergoing radical gastrectomy for GC and analyzed retrospectively. Patients received either peripheral parenteral nutrition (PPN) of 4.3% glucose fluid with regular diet (control group, n=43) or PPN of 7.5% glucose fluid containing amino acids plus oral nutritional supplement (ONS) rich in protein with regular diet (amino acids group, n=40) following gastrectomy. The percentages of BWL and SML from preoperative values to those at 7 days and 1 month after surgery were compared between the two groups.

RESULTS

The %BWL and %SML at 7 days after surgery were significantly lower in the amino acids group than those in the control group (%BWL, -2.4±1.7% vs. -4.2±1.8%; p<0.0001, %SML, -4.1±3.8 vs. -6.5±3.8; p=0.006). Moreover, the %BWL at 1 month after surgery was significantly lower in the amino acids group compared to that in the control group (- 4.6±2.9% vs. -6.1±2.6%; p=0.01); however, the %SML was similar between the two groups. The hematological nutritional parameters were similar between the two groups.

CONCLUSION

Amino acids nutrition by PPN and ONS following gastrectomy prevented postoperative BWL and SML in the early period after surgery in GC patients.

Favorable control of hepatocellular carcinoma with peritoneal dissemination by surgical resection using indocyanine green fluorescence imaging: a case report and review of the literature

BACKGROUND

The optimal management for peritoneal dissemination in patients with hepatocellular carcinoma remains unclear. Although several reports have described the usefulness of surgical resection, the indications should be carefully considered. Herein, we report the case of a patient with hepatocellular carcinoma with peritoneal recurrence who underwent surgical resection using an indocyanine green fluorescence navigation system and achieved favorable disease control.

CASE PRESENTATION

A 45-year-old Asian woman underwent left hemihepatectomy for a ruptured hepatocellular carcinoma. Seventeen months after the initial surgery, a single nodule near the cut surface of the liver was detected on computed tomography, along with elevation of tumor markers. The patient was diagnosed with peritoneal metastasis and underwent a surgical resection. Twelve months later, a single nodule on the dorsal side of the right hepatic lobe was detected on computed tomography, and we performed surgical resection. Indocyanine green (0.5 mg/kg) was intravenously administered 3 days before surgery, and the indocyanine green fluorescence imaging system revealed clear green fluorescence in the tumor, which helped us perform complete resection. Indocyanine green fluorescence enabled the detection of additional lesions that could not be identified by preoperative imaging, especially in the second metastasectomy. There was no further recurrence at 3 months postoperatively.

CONCLUSION

When considering surgical intervention for peritoneal recurrence in patients with hepatocellular carcinoma, complete resection is mandatory. Given that disseminated nodules are sometimes too small to be detected by preoperative imaging studies, intraoperative indocyanine green fluorescence may be an essential tool for determining the indications for surgical resection.

The Gastrohepatic Ligament Approach in Robotic Spleen-Preserving Distal Pancreatectomy with Resection of the Splenic Vessels: The Superior Window Approach in the Warshaw Technique

BACKGROUND

There have been few studies reporting on the surgical approaches of minimally invasive spleen-preserving distal pancreatectomy (SPDP). Herein, we present two cases who underwent robotic SPDP with resection of the splenic vessels using our novel gastrohepatic ligament approach (the superior window approach in the Warshaw technique).

METHODS

Our gastrohepatic ligament approach in robotic SPDP consists of four steps: step 1, the gastrohepatic ligament transection; step 2, dissection around the pancreas; step 3, transection of the pancreas; and step 4, resection of the splenic vessels (the Warshaw technique).

RESULTS

Starting with the gastrohepatic ligament transection, the pancreas was directly dissected with neither dissecting the gastrocolic ligament nor retracting the stomach. The mean operative time was 217 min with minimal estimated blood loss. Both of the patients had no postoperative morbidity.

CONCLUSIONS

The gastrohepatic ligament approach may be helpful and optional in robotic SPDP with the Warshaw technique.

Adenomatoid mesothelioma arising from the diaphragm: a case report and review of the literature

BACKGROUND

Adenomatoid mesothelioma is a rare subtype of malignant mesothelioma that can be confused with adenomatoid tumors, which are classified as benign. The clinical features and optimal management of adenomatoid mesothelioma have not been elucidated in the literature. In this report, we present an extremely rare case of adenomatoid mesothelioma that developed on the peritoneal surface of the diaphragm as well as a literature review of adenomatoid mesothelioma in the abdominal cavity.

CASE PRESENTATION

The patient was a 61-year-old Japanese woman who had undergone resection of a malignant peripheral nerve sheath tumor of the hand 18 years prior. She was diagnosed with clinical stage I lung adenocarcinoma on follow-up chest radiography. Simultaneously, a 20-mm enhancing nodule with slow growth on the right diaphragm was detected on contrast-enhanced computed tomography. She presented no specific clinical symptoms. At this point, the lesion was suspected to be a hypervascular tumor of borderline malignancy, such as a solitary fibrous tumor. After a left upper lobectomy for lung adenocarcinoma, she was referred to our department, and laparoscopic tumor resection was performed. Adenomatoid tumors were also considered based on the histopathological and immunohistochemical analyses, but we made the final diagnosis of adenomatoid mesothelioma using the results of the genetic profile. The patient remains alive, with no recurrence noted 6 months after surgery.

CONCLUSION

We encountered a valuable case of adenomatoid mesothelioma of peritoneal origin. There are some previously reported cases of adenomatoid mesothelioma and adenomatoid tumors that may need to be recategorized according to the current classification. It is important to accumulate and share new findings to clarify the clinicopathological characteristics and genetic status of adenomatoid mesothelioma.

Optimal surveillance of intraductal papillary mucinous neoplasms of the pancreas focusing on remnant pancreas recurrence after surgical resection

BACKGROUND

The international consensus guidelines for intraductal papillary mucinous neoplasm of the pancreas (IPMN) presented clinical features as indications for surgery. Whereas surveillance for recurrence, including de novo lesions, is essential, optimal surveillance protocols have not been established.

AIM AND METHODS

This study aimed to assess the clinical features of recurrence at the remnant pancreas (Rem-Panc) and extra-pancreas (Ex-Panc) after surgery for IPMN. Ninety-one patients of IPMN that underwent detailed preoperative assessment and pancreatectomy were retrospectively analyzed, focusing especially on the type of recurrence.

RESULTS

The IPMNs were finally diagnosed as low-grade dysplasia (LDA, n = 42), high-grade dysplasia (HAD, n = 19), and invasive carcinoma (IPMC, n = 30). Recurrence was observed in 26 patients (29%), of which recurrence was seen at Rem-Panc in 19 patients (21%) and Ex-Panc in 7 patients (8%). The frequency of Rem-Panc recurrence was 10% in LDA, 21% in HDA, and 37% in IPMC. On the other hand, Ex-Panc recurrence was observed only in IPMC (23%). Ex-Panc recurrence showed shorter median recurrence-free survival (RFS) and overall survival (OS) than Rem-Panc recurrence (median RFS 8 months vs. 35 months, p < 0.001; median OS 25 months vs. 72 months, p < 0.001). Regarding treatment for Rem-Panc recurrence, repeat pancreatectomy resulted in better OS than no repeat pancreatectomy (MST 36 months vs. 15.5 months, p = 0.033). On multivariate analysis, main duct stenosis or disruption as a preoperative feature (hazard ratio [HR] 10.6, p = 0.002) and positive surgical margin (HR 4.4, p = 0.018) were identified as risk factors for Rem-Panc recurrence.

CONCLUSIONS

The risk factors for Rem-Panc and Ex-Panc recurrence differ. Therefore, optimal surveillance on these features is desirable to ensure that repeat pancreatectomy for Rem-Panc recurrence can be an appropriate surgical intervention.

Prognostic Value of the Regional Lymph Node Station in Pancreatic Neuroendocrine Tumor

BACKGROUND/AIM

Little is known regarding the impact of lymph node dissection on survival benefit after curative resection for pancreatic neuroendocrine tumor (PNET). This study aimed to evaluate the efficacy of lymph node dissection based on tumor location of PNET.

PATIENTS AND METHODS

A retrospective study, including 50 patients with surgical resection for PNET between 2004 and 2020, was performed. The efficacy index (EI) was calculated by multiplication of the incidence of lymph node metastasis (LNM) at the station and the 5-year survival rate of patients with LNM at the station.

RESULTS

In the pancreatic head tumors, the peri-pancreatic head and superior mesenteric artery lymph node stations had high EI of 13.3 and 25, respectively. In contrast, other stations, including stations 8 and 12, had zero EI. In the pancreatic body and tail tumors, only the splenic artery lymph node station had a survival benefit from lymph node dissection with an EI of 6.7.

CONCLUSION

The extent of lymph node dissection for PNET should be decided based on the efficacy of lymph node dissection in accordance with tumor location. Our findings may be helpful in determining the extent of lymph node dissection required.

Surgical resection of mixed neuroendocrine-non-neuroendocrine neoplasm in the biliary system: a report of two cases

BACKGROUND

Mixed neuroendocrine-non-neuroendocrine neoplasm (MINEN) is a rare disease and there is scarce literature on its diagnosis, treatment, and prognosis. We encountered two unusual cases of MINEN in the biliary tract, one in the ampulla of Vater and the other in the distal bile duct. In this report, we describe the clinical course of these two cases in detail.

CASE PRESENTATION

Case 1: A 69-year-old woman presented with a chief complaint of epigastric pain. When endoscopic sphincterotomy and retrograde biliary drainage were performed for gallstone pancreatitis, an ulcerated lesion was found in the ampulla of the Vater. Based on the biopsy results, the lesion was diagnosed as the ampulla of Vater carcinoma and subtotal stomach-preserving pancreatoduodenectomy (SSPPD) was performed. Postoperative histopathological examination revealed the coexistence of adenocarcinoma and neuroendocrine carcinoma components, consistent with the diagnosis of MINEN. In addition, lymph node metastasis was found on the dorsal side of the pancreas and the metastatic component was adenocarcinoma. Adjuvant chemotherapy with etoposide and cisplatin was administered for 6 months, and presently the patient is alive without recurrence 64 months after surgery. Case 2: A 79-year-old man presented with a chief complaint of anorexia. Cholangiography showed severe stenosis of the distal bile duct. A biopsy was conducted from the stenotic lesion and it revealed the lesion to be adenocarcinoma. A diagnosis of distal bile duct carcinoma was made, and SSPPD was performed. Histopathological examination revealed the coexistence of adenocarcinoma and neuroendocrine carcinoma components, and the tumor was confirmed as MINEN of the distal bile duct. No adjuvant chemotherapy was administered due to the poor performance status. 7 months later, the patient was found to have a liver metastasis.

CONCLUSION

We experienced two valuable cases of biliary MINEN. To identify better treatments, it is important to consider the diversity of individual cases and to continue sharing a variety of cases with different presentations.

Prognostic Value of the Regional Lymph Node Station in Pancreatoduodenectomy for Ampullary Carcinoma

BACKGROUND/AIM

The optimal extent of lymph node dissection for ampullary carcinoma is controversial. The aim of this study was to investigate the efficacy of lymph node dissection for ampullary carcinoma.

PATIENTS AND METHODS

Between 2000 and 2020, a total of 75 patients undergoing radical resection for ampullary carcinoma were included. The efficacy index (EI) was calculated by multiplication of the frequency of lymph node metastasis (LNM) at the station and the 5-year survival rate of patients with metastasis at the station.

RESULTS

Out of 75 patients, 14 had LNM. The EI for the peri-pancreatic head (station 13 and 17) and superior mesenteric artery (station 14) lymph node were 4.4 and 3.5, respectively. Whereas the peri-gastric (station 5 and 6), common hepatic artery (station 8), and liver hilum (station 12) lymph node stations had zero EI. Although the number of patients with the station 16 dissected was small (9%), the para-aortic (station 16) lymph nodes had the highest EI of 14.3 despite being distant lymph nodes.

CONCLUSION

We identified the distribution of LNM and survival benefit of lymph node dissection for ampullary carcinoma. Our results suggest that the optimal extent of lymph node dissection for ampullary carcinoma could be reconsidered.

Surgical technique of suprapancreatic D2 lymphadenectomy focusing on the posterior hepatic plexus for advanced gastric cancer

PURPOSE

Although D2 lymphadenectomy is currently considered a standard procedure for advanced gastric cancer (GC) worldwide, there is room for discussion about the appropriate range of suprapancreatic D2 lymphadenectomy. Focusing on the posterior hepatic plexus (PHP), which is not well recognized, we developed a surgical technique of suprapancreatic D2 lymphadenectomy, which we have called PHP-D2, and its short-term and long-term efficacies were evaluated in comparison with non-PHP-D2.

METHODS

GC patients who underwent distal gastrectomy with D2 lymphadenectomy between July 2006 and May 2013 were enrolled, from which patients who had peritoneal metastasis and/or were peritoneal cytology-positive during surgery were excluded. Their medical records were retrospectively reviewed.

RESULTS

Ninety-two patients (non-PHP-D2: 48, PHP-D2: 44) were enrolled. Shorter operation time (330 min vs 275 min, p < 0.0001) and less blood loss (290 mL vs 125 mL, p < 0.0001) were observed in PHP-D2, and no pancreatic fistulas were observed in PHP-D2. More lymph nodes of #11p (1 vs 1.5, p = 0.0328) and #12a lymph nodes (0 vs 1, p = 0.0034) were retrieved in PHP-D2, with no significant differences in #8a and #9 lymph nodes. Lymphatic recurrence was significantly less in PHP-D2 (p = 0.0166), and univariate and multivariate analyses showed that non-PHP-D2 was a significant risk factor for lymphatic recurrence (p = 0.0158), although there were no significant differences between non-PHP-D2 and PHP-D2 in 5-year overall survival and 5-year relapse-free survival.

CONCLUSION

PHP-D2 was a safe and feasible procedure that had the potential to reduce lymphatic recurrence, and it can be a standard procedure of D2 lymphadenectomy for advanced GC.

Adult Bochdalek hernia following living donor left hepatectomy repaired by thoracoscopy-assisted surgery: A case report

Bochdalek hernia is a congenital diaphragmatic hernia (DH). Herein, we report a case of adult Bochdalek hernia following living donor hepatectomy repaired by thoracoscopy-assisted surgery. A 36-year-old man underwent living donor left hepatectomy. Four months later, the patient presented with acute epigastric pain. Computed tomography found the left-sided DH in which the stomach was incarcerated into the pleural cavity without ischemic changes. As endoscopic intervention was unsuccessful, the herniated stomach was repositioned by thoracoscopy-assisted surgery. The 3-cm hernia orifice was found to have a smooth edge with no hernia sac, suggesting Bochdalek hernia, and the defect was primarily closed. The patient was followed up for 20 months without hernia recurrence. This is the first presentation of a case of Bochdalek hernia following donor hepatectomy. In cases of early detected DH, primary repair via a transthoracic approach with thoracoscopy-assisted surgery is safe and feasible.

Diagnostic Utility of the PD-L1 Immunostaining in Biopsy Specimens of Patients with Biliary Tract Neoplasms

BACKGROUND

Anti-programmed death 1/programmed death ligand 1 (PD1/PD-L1) antibodies have been successfully used as treatment agents for several solid tumors; however, it is difficult to predict their effectiveness. We evaluated whether biopsy specimens could predict the positive status of PD-L1 in surgically resected tissue.

METHODS

Among 91 patients who underwent tissue sampling with endoscopic or liver biopsy before surgery for biliary tract neoplasms in an academic center, 45 (49%) patients were selected for retrospective analysis because the quality and quantity of their biopsy specimens were adequate for histologic evaluation. We performed immunohistochemical staining to investigate the PD-L1 expression in both resected and biopsy specimens. The percentage of the positively stained cells was calculated for subsequent use in the correlation investigation.

RESULTS

The biopsy methods were endoscopic retrograde cholangiopancreatography (ERCP) in 28 cases, percutaneous liver biopsy in 10 cases, and endoscopic ultrasound fine-needle aspiration in 7 cases. Among the 45 patients, when patients with > 10% positive tumor cells in surgically resected tissues were regarded as truly positive PD-L1, the positive and negative concordance rates between surgically resected tissues and biopsy samples were 56% (5/9) and 100% (36/36), respectively. With regard to the use of preoperative biopsy as a diagnostic tool, all (5/5) PD-L1-positive patients had a positive resected specimen. The accuracy of each biopsy method was as follows: ERCP, 89% (25/28); fine-needle aspiration, 86% (6/7); and liver biopsy, 100% (10/10).

CONCLUSIONS

Biopsy samples could be a surrogate material for the assessment of the PD-L1 expression with substantial positive and high negative concordance rates.

Left Hemihepatectomy for Hepatocellular Carcinoma Following Esophagectomy with Retrosternal Gastric Tube Reconstruction for Esophageal Cancer

Approximately 4% of patients with esophageal cancer develop a second primary malignancy in the upper gastrointestinal trunk. However, hepatectomy following esophagectomy for esophageal cancer has rarely been reported. We report the case of a 70-year-old man who underwent an esophagectomy for esophageal cancer with retrosternal gastric tube reconstruction. Nine years later, he developed hepatocellular carcinoma with tumor thrombus involving the left portal vein, and was successfully treated with left hemihepatectomy. Special attention should be paid to avoiding incidental injury of the gastric tube as well as the right gastroepiploic artery during the hepatectomy.

Multiple Hepatolithiasis Following Hepaticojejunostomy Successfully Treated with Left Hemihepatectomy and Double Hepaticojejunostomy Reconstruction

Surgical intervention for hepatolithiasis following hepaticojejunostomy (HJ) has rarely been reported. Herein, we present a case of post-HJ multiple hepatolithiasis treated with left hemihepatectomy with double HJ reconstruction. A 72-year-old woman who had undergone HJ for iatrogenic bile duct injury developed repeated cholangitis due to complicated hepatolithiasis accompanied by an atrophied left hepatic lobe and HJ stricture. Since endoscopic intervention was unsuccessful, the patient underwent left hemihepatectomy with HJ re-anastomoses of the common hepatic duct and left hepatic duct (double HJ technique). The double HJ technique with hepatectomy can be a useful option for treating complicated hepatolithiasis following HJ.

Anti-PD-1 antibody monotherapy versus anti-PD-1 plus anti-CTLA-4 combination therapy as first-line immunotherapy in unresectable or metastatic mucosal melanoma: a retrospective, multicenter study of 329 Japanese cases (JMAC study)

Background

Anti-programmed cell death protein 1 (PD-1) antibody monotherapy (PD1) has led to favorable responses in advanced non-acral cutaneous melanoma among Caucasian populations; however, recent studies suggest that this therapy has limited efficacy in mucosal melanoma (MCM). Thus, advanced MCM patients are candidates for PD1 plus anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) combination therapy (PD1 + CTLA4). Data on the efficacy of immunotherapy in MCM, however, are limited. We aimed to compare the efficacies of PD1 and PD1 + CTLA4 in Japanese advanced MCM patients.

Patients and methods

We retrospectively assessed advanced MCM patients treated with PD1 or PD1 + CTLA4 at 24 Japanese institutions. Patient baseline characteristics, clinical responses (RECIST), progression-free survival (PFS), and overall survival (OS) were estimated using Kaplan–Meier analysis, and toxicity was assessed to estimate the efficacy and safety of PD1 and PD1 + CTLA4.

Results

Altogether, 329 patients with advanced MCM were included in this study. PD1 and PD1 + CTLA4 were used in 263 and 66 patients, respectively. Baseline characteristics were similar between both treatment groups, except for age (median age 71 versus 65 years; P < 0.001). No significant differences were observed between the PD1 and PD1 + CTLA4 groups with respect to objective response rate (26% versus 29%; P = 0.26) or PFS and OS (median PFS 5.9 months versus 6.8 months; P = 0.55, median OS 20.4 months versus 20.1 months; P = 0.55). Cox multivariate survival analysis revealed that PD1 + CTLA4 did not prolong PFS and OS (PFS: hazard ratio 0.83, 95% confidence interval 0.58-1.19, P = 0.30; OS: HR 0.89, 95% confidence interval 0.57-1.38, P = 0.59). The rate of ≥grade 3 immune-related adverse events was higher in the PD1 + CTLA4 group than in the PD1 group (53% versus 17%; P < 0.001).

Conclusions

First-line PD1 + CTLA4 demonstrated comparable clinical efficacy to PD1 in Japanese MCM patients, but with a higher rate of immune-related adverse events.

•

Anti-PD-1 plus anti-CTLA-4 antibody therapy (PD1 + CTLA4) is an option for patients with advanced mucosal melanoma (MCM).

•

Data on the efficacy of PD1 + CTLA4 compared with PD-1 monotherapy (PD1) for MCM, however, are limited.

•

We retrospectively analyzed data from 329 Japanese patients with advanced MCM treated with PD1 or PD1 + CTLA4.

•

No significant differences in objective response rate, progression-free survival, or overall survival were observed.

•

Immune-related adverse events resulting in treatment cessation were higher in the PD1 + CTLA4 group.

Technique of vessel-skeletonized parenchyma-sparing hepatectomy for the oncological treatment of bilobar colorectal liver metastases

BACKGROUND

To aid in the oncological management of multiple bilobar colorectal liver metastases (CRLMs), we describe a new surgical procedure, VEssel-Skeletonized PArenchyma-sparing Hepatectomy (VESPAH).

STUDY DESIGN

Of 152 patients with CRLMs treated with hepatectomy, 33 patients had multiple bilobar liver metastases (≥8 liver metastases); their surgical procedures and clinical outcomes were retrospectively summarized and compared between those who underwent VESPAH and those who underwent major hepatectomy (Major Hx).

RESULTS

Of the 33 patients, 20 patients were resected by VESPAH (the VESPAH group) and 13 patients by major hepatectomy (Major Hx group). The median number of CRLMs was 13 (range, 8-53) in the VESPAH group and 10 (range, 8-41) in the Major Hx group (P=0.511). No operative mortality nor severe morbidity was observed in either group. The VESPAH group showed earlier recovery of remnant liver function after surgery than the Major Hx group; the incidence of grade B/C post hepatectomy liver failure was 5% in the VESPAH group and 38% in the Major Hx group, P=0.048). Intrahepatic tumor recurrence was confirmed in 14 (70%) and 7 (54%) patients in the VESPAH and Major Hx groups, respectively (P=0.416). There was no significant difference in median overall survival (OS) after hepatectomy between the two groups; the median OS was 47 months in the VESPAH group and 33 months in the Major Hx group (P=0.481). The VESPAH group showed the higher induction rate of adjuvant chemotherapy within 2 months after surgery (P=0.002) and total number of repeat hepatectomy for intrahepatic recurrence (P=0.060) than the Major Hx group.

CONCLUSIONS

VESPAH enables us to clear surgical navigation by hepatic vessel skeletonization and may enhance patient tolerability of not only adjuvant chemotherapy but also repeat hepatectomies during the patients' lifetimes.