Conversion surgery for initially unresectable locally advanced biliary tract cancer: A multicenter collaborative study conducted in Japan and Korea.

BACKGROUND: Although surgical resection is the only curative treatment for biliary tract cancer, in some cases, the disease is diagnosed as unresectable at initial presentation. There are few reports of conversion surgery after the initial treatment for unresectable locally advanced biliary tract cancer. This study aimed to evaluate the efficacy and safety of conversion surgery in patients with initially unresectable locally advanced biliary tract cancer. METHODS: We retrospectively collected clinical data from groups of patients in multiple centers belonging to the Japanese Society of Hepato-Biliary-Pancreatic Surgery and Korean Association of Hepato-Biliary-Pancreatic Surgery. We analyzed two groups of prognostic factors (pretreatment and surgical factors) and their relation to the treatment outcomes. RESULTS: A total of 56 patients with initially unresectable locally advanced biliary tract cancer were enrolled in this study of which 55 (98.2%) patients received chemotherapy, and 16 (28.6%) patients received additional radiation therapy. The median time from the start of the initial treatment to resection was 6.4 months. Severe postoperative complications of Clavien-Dindo grade III or higher occurred in 34 patients (60.7%), and postoperative mortality occurred in five patients (8.9%). Postoperative histological results revealed CR in eight patients (14.3%). The median survival time from the start of the initial treatment in all 56 patients who underwent conversion surgery was 37.7 months, the 3-year survival rate was 53.9%, and the 5-year survival rate was 39.1%. CONCLUSIONS: Conversion surgery for initially unresectable locally advanced biliary tract cancer may lead to longer survival in selected patients. However, more precise preoperative safety evaluation and careful postoperative management are required.

Genetic assessment of IPMN for predicting concomitant pancreatic ductal adenocarcinoma.

OBJECTIVE: Krüppel-like transcription factor 4(KLF4) mutations are more frequently observed in low-grade lesions than in high-grade lesions of intraductal papillary mucinous neoplasms (IPMN) of the pancreas. However, the role of KLF4 mutations in IPMNs with concomitant pancreatic ductal adenocarcinoma (PDAC) remains unclear. This study clarified the rate and effect of KLF4 mutations in IPMN with concomitant PDAC. METHODS: DNA was extracted from 65 formalin-fixed and paraffin-embedded samples from 52 patients including 13 IPMN with concomitant PDAC and 39 IPMN alone. A comprehensive screening was performed using next-generation sequencing (NGS) for the 5 IPMNs with concomitant PDAC and 5 IPMNs alone, followed by targeted sequencing for KLF4, GNAS, and KRAS mutations. RESULTS: In NGS screening, KRAS mutations were observed in all samples except for one, GNAS mutation in two IPMNs with concomitant PDAC, and a KLF4 mutation in one IPMN with concomitant PDAC. Targeted sequence detected KLF4 mutations in 11 of the 52 IPMNs. Concomitant PDAC developed only in the non-intestinal, non-invasive, and branch duct IPMN cases, and KLF4 mutations were more frequent in this IPMN type than in the other type (36% vs. 10%, p = 0.04). For this IPMN type with KLF4 mutation, PDAC-prediction sensitivity, specificity, and accuracy were 63%, 82%, and 79%, respectively. CONCLUSION: For selected IPMNs with non-intestinal, non-invasive, and branch duct, genetic assessment might be a helpful tool for predicting the possible development of concomitant PDAC, although a prospective validation study using a larger study population is needed.

Successful subtotal gastrectomy and hepatectomy for HER2-positive gastric cancer with liver metastasis after trastuzumab-based chemotherapy: a case report.

BACKGROUND: Conversion surgery (CS) after chemotherapy is weakly recommended as a promising tool for improving prognoses in patients with unresectable gastric cancer. Moreover, several investigators have demonstrated the clinical efficacy of subtotal gastrectomy (sTG) with a small remnant stomach for the nutritional status and surgical outcome compared with total gastrectomy. Here, we report a patient with liver metastasis from human epidermal growth factor receptor 2 (HER2)-positive gastric cancer who underwent sTG and hepatectomy after trastuzumab-based chemotherapy. CASE PRESENTATION: An 84-year-old male patient was diagnosed with HER2-positive gastric cancer with a single liver metastasis. He was treated with eight courses of trastuzumab in combination with S-1 and oxaliplatin as first-line chemotherapy. The primary tumor and liver metastasis shrank significantly. The metastatic liver lesion's reduction rate was 65%. According to the Response Evaluation Criteria in Solid Tumors, the patient had a partial response. Therefore, he underwent an sTG with D2 lymphadenectomy and partial hepatectomy of segment 2. Histopathological examination revealed a grade 3 histological response without lymph node metastases from the primary tumor. No viable cancer cells were observed in the resected liver specimens. The patient received adjuvant chemotherapy with S-1. The postoperative quality of life (QOL) evaluated using the Postgastrectomy Syndrome Assessment Scale-45 was maintained, and the patient was still alive 8 months after the CS without recurrence. CONCLUSIONS: An sTG with a small remnant stomach might be clinically useful for preventing a decline in QOL and improving prognoses in patients with stage IV gastric cancer after chemotherapy.

Metal-free laparoscopic distal pancreatectomy using transpancreatic mattress suture with polyglycolic acid sheet and fibrin glue: A case report.

Laparoscopic distal pancreatectomy (LDP) is the standard surgery for malignant and premalignant tumors of the pancreatic body and tail. A stapler is commonly used to close the pancreatic stump due to its simplicity; however, the use of a stapler is associated with the risk of metal allergy and postoperative pancreatic fistula, especially in thick pancreases. Here, we present a case of LDP without metal instruments, including staplers and clips, in a 54-year-old woman with a metal allergy and a thick pancreas. The pancreatic stump was closed using the transpancreatic mattress suture method with a polyglycolic acid sheet (PGA) and fibrin glue. The postoperative course was uneventful. Metal-free LDP is useful and can be adopted regardless of the patient's background, such as a metal allergy or pancreatic thickness.

Efficacy of laparoscopic liver resection for small hepatocellular carcinoma located in the posterosuperior segments: A multi-institutional study using propensity score matching by the Kyushu Study Group of Liver Surgery.

AIM: Laparoscopic liver resection (LLR) for hepatocellular carcinoma (HCC) located in the posterosuperior segments (PS) have generally been considered more difficult than those for HCC in anterolateral segments (AL), but may be safe and feasible for selected patients with accumulated experience. In the present study, we investigated the effectiveness of LLR for single nodular HCCs ≤3 cm located in PS. METHODS: In total, 473 patients who underwent partial liver resection for single nodular HCCs ≤3 cm at the 18 institutions belonging to the Kyusyu Study Group of Liver Surgery from January 2010 to December 2018 were enrolled. The short-term outcomes of laparoscopic partial liver resection and open liver resection (OLR) for HCCs ≤3 cm, with subgroup analysis of PS and AL, were compared using propensity score-matching analysis. Furthermore, results were also compared between LLR-PS and LLR-AL. RESULTS: The original cohort of patients with HCC ≤3 cm included 328 patients with LLR and 145 with OLR. After matching, 140 patients with LLR and 140 with OLR were analyzed. Significant differences were found between groups in terms of volume of blood loss (median, 55 vs. 287 ml, p < 0.001), postoperative complications (0.71 vs. 8.57%, p = 0.003), and postoperative hospital stay (median, 9 vs. 14 days, p < 0.001). The results of subgroup analysis of PS were similar. Short-term outcomes did not differ significantly between LLR-PS and LLR-AL after matching. CONCLUSIONS: Laparoscopic partial resection could be the preferred option for single nodular HCCs ≤3 cm located in PS.

Usefulness of cranio-dorsal approach for laparoscopic left lateral sectionectomy.

Most surgeons perform laparoscopic left lateral sectionectomy (Lap LLS) using the caudo-peripheral approach (C-P approach). However, recently, a cranio-dorsal approach (C-D approach) has been applied to various types of hepatectomy owing to its advantage of preventing split injury. No studies yet have compared the perioperative outcomes of Lap LLS using each approach. Therefore, this study aimed to determine whether the C-D approach is useful for Lap LLS by comparing its perioperative outcomes with the C-P approach. Data of patients who underwent Lap LLS in our institution between 2010 and 2022 for liver tumors were retrospectively collected. We compared the perioperative outcomes of Lap LLS using a conventional C-P approach, which transects hepatic parenchyma in the caudo-peripheral direction and a C-D approach, which transects hepatic parenchyma in the cranio-caudal direction. All surgeries were performed only by board-certified expert surgeons to minimize technical bias. Furthermore, the perioperative procedures employed at our institution remained unchanged throughout the study period. A total of 36 patients were included in the study (C-P approach, n = 25; C-D approach, n = 11). The C-D approach showed a significantly shorter operation time than the C-P approach (median, 225 min vs. 262 min, p = 0.04). In addition, the C-D approach showed significantly lower blood loss than the C-P approach (median, 20 mL vs. 100 mL, p < 0.01). Other parameters, such as morbidity and hospital stay, were comparable between groups. The C-D approach could offer better surgical outcomes than the conventional C-P approach.

[A Case of Curative Resection Following TNT for Locally Advanced Rectal Cancer with Liver Metastasis].

The standard treatment of locally advanced rectal cancer is preoperative chemoradiotherapy(CRT)in Europe and the United States, while that is surgical excision and lateral pelvic lymph node dissection followed by adjuvant chemotherapy in Japan. Recently, total neoadjuvant therapy(TNT), which combines neoadjuvant chemotherapy and preoperative CRT, have been popular. We performed curative excision for initially locally advanced rectal cancer with liver metastasis after TNT. A 61- year-old woman was diagnosed as having rectal cancer with liver metastasis and invasion of the uterus, vagina, bladder, and left ureter. The patient underwent 8 courses of FOLFOX plus bevacizumab, followed by radiotherapy, and totally pelvic excision for the primary tumor. Because of liver metastasis progression, hepatectomy was performed after 6 courses of FOLFIRI plus panitumumab. The patient has been cancer free for 20 months to date. TNT is considered to be an effective strategy for the treatment of large locally advanced rectal cancer.

Risk Factors of Complications from Central Bisectionectomy (H458) for Hepatocellular Carcinoma: A Multi-Institutional Single-Arm Analysis.

BACKGROUND: This study aims to clarify the perioperative risk factors and short-term prognosis of central bisectionectomy (CB) for hepatocellular carcinoma (HCC). METHODS: Surgical data from 142 selected patients out of 171 HCC patients who underwent anatomical CB (H458) between 2005 and 2020 were collected from 17 expert institutions in a single-arm retrospective study. RESULTS: Morbidities recorded by the International Study Group of Liver Surgery (ISGLS) from grade BC post-hepatectomy liver failure (PHLF) and bile leakage (PHBL), or complications requiring intervention were observed in 37% of patients. A multivariate analysis showed that increased blood loss (iBL) > 1500 mL from PHLF (risk ratio [RR]: 2.79), albumin level < 4 g/dL for PHBL (RR, 2.99), involvement of segment 1, a large size > 6 cm, or compression of the hepatic venous confluence or cava by HCC for all severe complications (RR: 5.67, 3.75, 6.51, and 8.95, respectively) (p < 0.05) were significant parameters. Four patients (3%) died from PHLF. HCC recurred in 50% of 138 surviving patients. The three-year recurrence-free and overall survival rates were 48% and 81%, respectively. CONCLUSIONS: Large tumor size and surrounding tumor involvement, or compression of major vasculatures and the related iBL > 1500 mL were independent risk factors for severe morbidities in patients with HCC undergoing CB.

Multiomics identifies the link between intratumor steatosis and the exhausted tumor immune microenvironment in hepatocellular carcinoma.

BACKGROUND AND AIMS: Immunotherapy has become the standard-of-care treatment for hepatocellular carcinoma (HCC), but its efficacy remains limited. To identify immunotherapy-susceptible HCC, we profiled the molecular abnormalities and tumor immune microenvironment (TIME) of rapidly increasing nonviral HCC. APPROACHES AND RESULTS: We performed RNA-seq of tumor tissues in 113 patients with nonviral HCC and cancer genome sequencing of 69 genes with recurrent genetic alterations reported in HCC. Unsupervised hierarchical clustering classified nonviral HCCs into three molecular classes (Class I, II, III), which stratified patient prognosis. Class I, with the poorest prognosis, was associated with TP53 mutations, whereas class III, with the best prognosis, was associated with cadherin-associated protein beta 1 (CTNNB1) mutations. Thirty-eight percent of nonviral HCC was defined as an immune class characterized by a high frequency of intratumoral steatosis and a low frequency of CTNNB1 mutations. Steatotic HCC, which accounts for 23% of nonviral HCC cases, presented an immune-enriched but immune-exhausted TIME characterized by T cell exhaustion, M2 macrophage and cancer-associated fibroblast (CAF) infiltration, high PD-L1 expression, and TGF-ß signaling activation. Spatial transcriptome analysis suggested that M2 macrophages and CAFs may be in close proximity to exhausted CD8+ T cells in steatotic HCC. An in vitro study showed that palmitic acid-induced lipid accumulation in HCC cells upregulated PD-L1 expression and promoted immunosuppressive phenotypes of cocultured macrophages and fibroblasts. Patients with steatotic HCC, confirmed by chemical-shift MR imaging, had significantly longer PFS with combined immunotherapy using anti-PD-L1 and anti-VEGF antibodies. CONCLUSIONS: Multiomics stratified nonviral HCCs according to prognosis or TIME. We identified the link between intratumoral steatosis and immune-exhausted immunotherapy-susceptible TIME.

Are intratumoral microbiota involved in the progression of intraductal papillary mucinous neoplasms of the pancreas?

BACKGROUND: Microbiota have been reported to influence the development of various gastrointestinal neoplasms through the mechanism of sustained inflammation; however, few data are available regarding their influence on intraductal papillary mucinous neoplasms. The aim of this study was to assess the association between specific microbiota and the clinicopathologic characteristics of intraductal papillary mucinous neoplasms of the pancreas. METHODS: DNA was extracted from formalin-fixed, paraffin-embedded samples of 30 patients who underwent pancreatectomy for intraductal papillary mucinous neoplasm, and polymerase chain reaction was used to create sequence libraries using the primer set for the V3 and V4 region of 16S recombinant DNA. Filtered sequence reads were then processed into operational taxonomic units with a 97% identity threshold and the relative abundance of bacteria compared between the 2 groups using operational taxonomic units. RESULTS: There was a trend toward fewer Firmicutes and more Proteobacteria and Fusobacteria in the relative abundance of main duct operational taxonomic units than in branch duct operational taxonomic units. The relative abundances of Bacteroidetes (P < .01) and Fusobacteria (P = .04) were significantly higher in invasive intraductal papillary mucinous neoplasms than in noninvasive intraductal papillary mucinous neoplasms. The relative abundance of the intestinal type was significantly lower in Firmicutes than the relative abundance of the nonintestinal type (P = .04). Notably, main duct operational taxonomic units with the intestinal subtype were affected by increased proportions of Proteobacteria and Fusobacteria, and Fusobacteria were abundant in the intestinal type of invasive main duct operational taxonomic units. CONCLUSION: Intratumoral microbiota may be involved in the progression of operational taxonomic units.

Surgical Stress Evaluation of Left Lateral Sectionectomy Based on Skeletal Muscle Catabolism.

BACKGROUND: By examining skeletal muscle catabolism, we aimed to investigate whether laparoscopic left lateral sectionectomy (LLS) is less invasive compared with the open approach. METHODS: The psoas muscle index (PMI) was measured using computed tomography images before and after surgery. We assessed the relationship between the perioperative PMI reduction rate and the estimation of physiologic ability and surgical stress (E-PASS) score and then compared the PMI reduction rates associated with different approaches. RESULTS: Of the 31 patients, 13 and 18 underwent the open and laparoscopic approaches, respectively. A strong correlation was observed between the PMI reduction rates and surgical stress scores (SSS) ( r =0.561, P <0.01). The laparoscopic approach was associated with a significantly lower PMI reduction rate ( P <0.01) and SSS ( P <0.01) than the open approach. CONCLUSION: Laparoscopic LLS should be less invasive than the open approach from the perspective of not only perioperative outcomes but also skeletal muscle catabolism.

Curative resection after chemotherapy and chemoradiotherapy for postoperative recurrence of pancreatic tail cancer in the abdominal wall: a case report.

BACKGROUND: Locoregional recurrence and metastasis to the liver, peritoneum, and lung are the most common recurrent patterns of pancreatic ductal adenocarcinoma (PDAC) after radical resection. Recurrence in the abdominal wall is extremely rare. Herein, we report our experience with a patient who had recurrent PDAC in the abdominal wall with long-term survival by means of multidisciplinary therapy. CASE PRESENTATION: A 76-year-old Japanese woman was diagnosed with resectable pancreatic tail cancer. She underwent distal pancreatectomy with regional lymphadenectomy after two cycles of gemcitabine plus S-1 as neoadjuvant therapy. She also received eight cycles of S-1 as adjuvant chemotherapy. Approximately 14 months after the initial surgery, imaging examinations identified a mass suggesting recurrence in the abdominal wall at the middle wound that involved the transverse colon. After two cycles of gemcitabine plus nab-paclitaxel, chemoradiotherapy (S-1 plus 45 Gy) and seven cycles of modified FOLFIRINOX (5-fluorouracil/leucovorin, irinotecan, and oxaliplatin) were administered. The patient did not develop any new recurrent lesions during chemotherapy and chemoradiotherapy. Therefore, the recurrent lesion in the abdominal wall and the involved transverse colon were resected. We confirmed the lack of peritoneal dissemination during surgery. Pathological examination revealed that the resected lesion was metastasis of primary PDAC, and the surgical margin was 1 mm. However, re-recurrence localized in the abdominal wall was detected 9 months later. The re-recurrent lesion was diagnosed as local recurrence of the first recurrent lesion. We performed a second resection of the abdominal wall using a femoral myocutaneous flap to achieve sufficient surgical margin. The pathological findings of the resected specimen were the same as those of the previous specimens, and the resection margin was negative. The patient's postoperative course was uneventful. Seven years after the initial surgery and 3 years and 7 months after the third surgery, the patient is alive with no signs of recurrence. CONCLUSIONS: Long-term survival could be achieved by radical resection with sufficient surgical margins for recurrence of PDAC in the abdominal wall if new other recurrent lesions, including peritoneal dissemination, are prevented through chemotherapy.

Spread of lymph node metastasis and adjuvant therapy for distal cholangiocarcinoma.

BACKGROUND: Lymphatic metastasis is a major route of metastasis in distal cholangiocarcinoma (DCC). The present study aimed to elucidate the pattern of lymph node (LN) metastasis and the effectiveness of LN dissection and postoperative adjuvant chemotherapy in patients with DCC. METHODS: Patients who underwent surgical resection with curative intent for DCC were enrolled. The nomenclature of the LN stations was defined according to the Japanese Society of Hepato-Biliary-Pancreatic Surgery guidelines. Effectiveness of LN dissection of each station was calculated using frequency of LN metastasis to the station and 5-year survival rate of patients with LN metastasis to that station. RESULTS: Of the 105 patients included in the study, 46 (43.8%) had LN metastasis, and 43 (41.0%) underwent postoperative adjuvant therapy. LN metastasis, serum carbohydrate antigen (CA) 19-9 level > 37 U/mL, and positive bile duct margin were independent risk factors for shorter overall survival (OS). The most common metastatic LN station at surgery was No. 13 (32.7%), followed by No. 12 (19.2%), No. 17 (9.6%), and No. 8 (6.6%). There was no effectiveness of LN dissection of the station No. 8, 14, and 16. Adjuvant chemotherapy was significantly associated with longer OS in patients with LN metastasis but not in those with positive ductal margins or serum CA 19-9 level > 37 U/mL. CONCLUSIONS: Postoperative adjuvant chemotherapy was associated with a better prognosis in patients with DCC and LN metastasis. However, a more effective therapeutic strategy is required to improve the prognosis of patients with other negative prognostic factors.

Successful conversion surgery for stage IV gastric cancer with liver metastases after second-line chemotherapy with ramucirumab and paclitaxel: a case report.

BACKGROUND: In recent years, conversion surgery after chemotherapy has been considered a promising strategy for improving the prognosis of patients with stage IV gastric cancer. However, there are few reports on conversion gastrectomy after second-line chemotherapy. Here, we report a case of long-term survival of a patient with liver metastases from gastric cancer who underwent conversion surgery after second-line chemotherapy with ramucirumab and paclitaxel. CASE PRESENTATION: A 77-year-old man complaining of weight loss was diagnosed with human epidermal growth factor receptor 2-positive gastric cancer with multiple liver metastases. Although the patient initially received trastuzumab-based chemotherapy, it was discontinued, because he experienced trastuzumab-induced infusion reactions. Thereafter, he was treated with six courses of S-1 plus cisplatin and six courses of ramucirumab plus paclitaxel as the first- and second-line regimens, respectively. The primary tumor and liver metastases remarkably shrank, and the reduction rate of the measurable metastatic liver lesions was 81.1%. According to the Response Evaluation Criteria in Solid Tumors, the patient responded partially. Therefore, he underwent total gastrectomy with D2 lymphadenectomy and partial hepatectomy of segments 3 and 4. Pathological examination revealed tumor invasion into the muscularis propria, a grade 1a histological response, and no lymph node metastases. No viable cancer cells were identified in the specimens resected from liver segments 3 and 4. Accordingly, the patient was pathologically diagnosed with stage IB (ypT2N0M0). Postoperatively, the patient received adjuvant chemotherapy with S-1 for 6 months, and he survived without recurrence for 42 months after conversion surgery. CONCLUSIONS: Conversion surgery might be clinically useful for improving survival in certain patients with gastric cancer, including those who previously received second-line chemotherapy.

Multidisciplinary treatment of advanced or recurrent solid pseudopapillary neoplasm of the pancreas: three case reports.

BACKGROUND: Solid pseudopapillary neoplasm (SPN) is a rare pancreatic tumor that predominantly affects young females. Prognosis is excellent; however, 10-15% of patients show metastasis at the time of surgery or develop tumor recurrence after pancreatectomy. CASE PRESENTATION: We reviewed the clinical course of three patients with advanced or recurrent SPN and subsequently underwent multidisciplinary treatment at our institution between 2002 and 2019. The primary tumor was resected in all three patients, and metastases were also resected if indicated. Intensive combined therapy, including re-resection, chemotherapy, ablation, arterial chemoembolization, and radiation therapy, allowed all patients to survive for a long time. The literature review showed that resection seems to be more effective than other treatments for metastatic SPN. CONCLUSIONS: Multidisciplinary treatment, including resection, may improve the prognosis of patients with SPN with recurrence or metastasis.

Postoperative recurrence with right cervical lymph node metastasis in hepatocellular carcinoma: a case report.

BACKGROUND: Hepatocellular carcinoma (HCC) patients with metastases to the cervical lymph nodes are extremely rare, and its clinical course is characterized by rapidly progressive disease. Hence, there have been no reports of metastatic cervical lymph node recurrence indicated after a long postoperative surveillance period. CASE PRESENTATION: The patient was a 63-year-old male who underwent right hepatectomy for HCC of the right upper lobe. Three years after resection, metastatic lymph node recurrence was detected in the subdiaphragm, superior mediastinum, and right cervical lymph nodes. The patient underwent excisional biopsy of the cervical lymph node, followed by molecular-targeted therapy and radiation therapy. Lenvatinib reduced the size of all metastatic lymph nodes and the patient survived for a relatively long period of 43 months after the recurrence was detected. CONCLUSIONS: After resection of HCC in the right upper lobe, there is the possibility of metastatic lymph node recurrence in unusual sites, including the cervical region, and lenvatinib may be effective in those recurrences.

Malignant perivascular epithelioid cell neoplasm in the liver: report of a pediatric case.

BACKGROUND: Perivascular epithelioid cell neoplasm (PEComa) in a child is very rare. We herein report the first malignant case of PEComa developing in the liver of a pediatric patient. CASE PRESENTATION: A 10-year-old boy visited a private clinic with prolonged fever of unknown etiology. Abdominal ultrasonography was performed to evaluate the fever's origin, revealing a large tumor in the liver. He was thus referred to a nearby hospital to investigate the tumor further. Enhanced computed tomography (CT) showed a 6.8 × 5.9 × 10.5-cm solid lesion on S4 and S5. On magnetic resonance imaging (MRI), the tumor had a low signal intensity on T1 imaging and high signal intensity on T2 imaging, with partial diffusion restriction. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) showed a marked uptake in the mass lesion with no evidence of metastasis. The patient was negative for all tumor markers, including AFP, CEA and PIVKA-II. The results of a needle biopsy suggested hepatocellular carcinoma. The tumor's rapid growth suggested malignancy. Hepatic segmentectomy (S4 + S5 + S8) was performed. The tumor was resected en bloc with a margin. Microscopically, the tumor showed atypical spindle, polygonal or oval-shaped cells with a high nuclear grade, and vascular invasion. Immunohistochemistry was positive for alpha-smooth muscle antigen (α-SMA), human melanin black-45 (HMB-45) and melan A. The pathological diagnosis was malignant PEComa. In the 6 months after surgery, the patient complained of shoulder pain. MRI showed a dumbbell-shaped tumor at the 2nd thoracic vertebrae, which was confirmed to be bone metastasis of PEComa. After chemotherapy, including ifosfamide and doxorubicin, vertebrectomy was performed. Two years later, thoracoabdominal CT showed a 10-cm solid mass occupying the pelvis and a 15-mm nodule in the middle lobe of the right lung. Under a diagnosis of peritoneal and lung metastases, they were surgically removed and metastasis of PEComa was pathologically confirmed. Four months after the 2nd relapse, pelvic metastasis appeared again and mTOR (mammalian target of rapamycin) inhibitor was initiated. To our knowledge, this is the first report of malignant hepatic PEComa in a pediatric patient. CONCLUSION: Although extremely rare, malignant hepatic PEComa can develop in a child.

Clinical Utility and Limitation of Diagnostic Ability for Different Degrees of Dysplasia of Intraductal Papillary Mucinous Neoplasms of the Pancreas Using 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography.

The diagnostic value of 18F-fluorodeoxyglucose (FDG) uptake in the management of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas remains unclear. This study aimed to assess the role of FDG uptake in the diagnosis of different degrees of dysplasia of IPMNs. We retrospectively analyzed the following three points in 84 patients with IPMNs: (1) risk factors to predict high-grade dysplasia (HGD) and invasive carcinoma (INV); (2) the relationship between FDG uptake and glucose transporter 1 (GLUT-1) expression; and (3) the relationship between FDG uptake and the presence of mural nodules. The histopathological diagnosis was low-grade dysplasia (LGD) in 43 patients, HGD in 16, and INV in 25. The maximum standardized uptake value (SUV-max) was significantly higher in INV than in LGD/HGD (p < 0.0001, p = 0.0136). The sensitivity and specificity to discriminate INV from LGD/HGD were 80.0% and 86.2%, respectively, using the receiver operator characteristic curve, when the optimal cutoff score of SUV-max was set at 4.03. Those values were not different between HGD and LGD. More than half of HGD patients had low GLUT-1 expression. Taken together, FDG-PET/CT is useful in distinguishing between non-invasive and invasive IPMN. Our results offer critical information that may determine surgical treatment strategies.

Useful Technique for Creating a Good Liver Parenchymal Visual Transection Plane During Laparoscopic Partial Hepatectomy.

BACKGROUND: Creating a good surgical visual field is one of the most important factors for performing a successful surgery. Here, we introduce a useful technique for creating a good liver parenchymal visual transection plane during laparoscopic partial hepatectomy and compare the perioperative outcomes of our current technique with those of conventional techniques. METHODS: We reviewed the data of patients who underwent laparoscopic partial hepatectomy between July 2016 and December 2020. The current technique for creating transection planes was first applied in our department in April 2019. The patients were divided into conventional (forceps) and current (silicone ring) technique groups, depending on the surgical technique. RESULTS: Twenty-eight and 12 patients underwent laparoscopic partial hepatectomy using the conventional and current techniques, respectively, when the difficulty level-as determined by IWATE criteria-was low. Although the tumor size was significantly larger (median: 22.5 vs. 15 mm, P=0.04) in the current technique group, the estimated intraoperative blood loss was significantly lower (median: 50 vs. 100 mL, P=0.01), and the median surgical margin was significantly longer (median: 7 vs. 3 mm, P=0.02). There were no significant between-group differences in surgical time (median: 344 vs. 240 min, P=0.14), postoperative hospital stay duration (median: 11 vs. 9.5 d, P=0.051), and the incidence of complications (P=0.63). CONCLUSION: We believe that the technique involving the use of a silicone ring can result in better surgical outcomes as it provides a good visual hepatic transection plane during laparoscopic partial hepatectomy.

Molecular Pathogenesis and Regulation of the miR-29-3p-Family: Involvement of ITGA6 and ITGB1 in Intra-Hepatic Cholangiocarcinoma.

The aggressive nature of intrahepatic cholangiocarcinoma (ICC) renders it a particularly lethal solid tumor. Searching for therapeutic targets for ICC is an essential challenge in the development of an effective treatment strategy. Our previous studies showed that the miR-29-3p-family members (miR-29a-3p, miR-29b-3p and miR-29c-3p) are key tumor-suppressive microRNAs that control many oncogenic genes/pathways in several cancers. In this study, we searched for therapeutic targets for ICC using the miR-29-3p-family as a starting point. Our functional studies of cell proliferation, migration and invasion confirmed that the miR-29-3p-family act as tumor-suppressors in ICC cells. Moreover, in silico analysis revealed that "focal adhesion", "ECM-receptor", "endocytosis", "PI3K-Akt signaling" and "Hippo signaling" were involved in oncogenic pathways in ICC cells. Our analysis focused on the genes for integrin-α6 (ITGA6) and integrin-ß1 (ITGB1), which are involved in multiple pathways. Overexpression of ITGA6 and ITGB1 enhanced malignant transformation of ICC cells. Both ITGA6 and ITGB1 were directly regulated by the miR-29-3p-family in ICC cells. Interestingly, expression of ITGA6/ITGB1 was positively controlled by the transcription factor SP1, and SP1 was negatively controlled by the miR-29-3p-family. Downregulation of the miR-29-3p-family enhanced SP1-mediated ITGA6/ITGB1 expression in ICC cells. MicroRNA-based exploration is an attractive strategy for identifying therapeutic targets for ICC.