[A Case of Simultaneous Laparoscopic Surgery for Intrahepatic Cholangiocarcinoma and Sigmoid Colon Cancer].

The patient was an 83-year-old woman. CT scan showed a 20 mm mass in the surgical anatomy of the medial segment (S4)of the liver, but the patient refused to undergo surgery and continued periodic clinical follow-up. After 1 year and 3 months of initial examination, a CT scan showed an enlargement of 36 mm. Therefore, surgical treatment was adopted. Preoperative lower gastrointestinal endoscopy revealed a type 1 tumor of the sigmoid colon quarter circumference 30 mm from the anal verge, and the biopsy led to a diagnosis of adenocarcinoma equivalent to tub 1. The hepatic mass showed heterogeneous contrast effect centered on the arterial phase margins and prolonged contrast effect in the equilibrium phase. Since the liver tumor was a single S4 mass with a 36 mm diameter, laparoscopic sigmoidectomy and laparoscopic partial hepatic resection were performed subsequently. Pathology results showed that the sigmoid colon tumor and hepatic S4 mass were predominantly well-differentiated and moderately-differentiated adenocarcinomas, respectively. Immunohistochemical results were cytokeratin 7 antibody-positive and cytokeratin 20 antibody-negative, leading to a definitive diagnosis of intrahepatic cholangiocarcinoma. The patient's postoperative course was well and was discharged from the hospital on postoperative day 12. After 1 year postoperatively, the patient remains recurrence-free.

[A Case of Gastric Perforation Due to an Unresectable Advanced Gastric Cancer That Achieved pCR after Conversion Surgery following SOX plus T-mab Therapy].

This case pertains to a 72-year-old man who visited the emergency department with a complaint of upper abdominal pain. On examination, we suspected gastric perforation due to gastric cancer and decided to perform emergency surgery. We performed laparoscopic omentoplasty and collected #4d lymph nodes that were enlarged on CT. The pathological diagnosis was lymph node metastasis. Based on CT findings, we determined it was Bulky N. For initial management, we performed 3 preoperative chemotherapy(SOX therapy)courses and staging laparoscopy. On surgery, extensive disseminated nodules on the abdominal wall, stomach wall, and liver surface were found, and ascites cytology revealed positive findings. Therefore, we did not perform primary lesion resection. Although the disseminated nodule did not pathologically show tumor cells, CY1 was found, resulting to a diagnosis of unresectable gastric cancer. Since the tumor was HER2 3+, we initiated SOX/trastuzumab therapy. After 16 courses, staging laparoscopy was performed as the lymph nodes had shrunk significantly. The results showed no tumor cells in ascites and the disseminated nodules, and laparoscopic total gastrectomy was subsequently performed. Pathological findings showed no tumor cells in the primary lesion or lymph nodes; therefore, a diagnosis of pathological complete response was made. Currently, the patient is alive without recurrence for 6 months after surgery.

[Two Cases of Unresectable Gastric Cancer Where Bleeding Was Controlled by Radiation].

Case 1: The patient was a 74-year-old man with a performance status(PS)of 0. He was referred to our department for pyloric gastric cancer with multiple liver, lung, and lymph node metastases. We started chemotherapy after making the diagnosis of an unresectable gastric cancer. During chemotherapy, the hemoglobin level dropped due to bleeding from the tumor. We attempted endoscopic hemostasis, which was not successful; therefore, we attempted a palliative radiotherapy. The total dose was 30 Gy in 10 Fr and hemostasis was achieved on the 10th day from the start of the radiotherapy. There were no adverse events due to the radiation, and the chemotherapy could be restarted 5 days after the end of the radiotherapy. Case 2: The patient was a 78-year-old man with a PS of 2. He was referred to our department because of vomiting and anemia. As a result of a close inspection, we made the diagnosis of an unresectable gastric body cancer with para-aortic lymph node metastasis and peritoneal dissemination, for which chemotherapy was initiated. Anemia was observed at the first visit, and we started radiotherapy to stop the tumor bleeding. The total dose was 30 Gy in 10 Fr, and hemostasis was achieved on the 12th day. There were no adverse events during the radiotherapy, and chemotherapy could be continued. Palliative radiotherapy is an available method of hemostasis that is less invasive than surgery or transcatheter arterial embolization and can be expected to have a certain effect for gastric cancer bleeding, although it takes several days to obtain a therapeutic effect.

Metal-Catalyzed Sequential Formation of Distant Bonds in Organic Molecules: Palladium-Catalyzed Hydrosilylation/Cyclization of 1,n-Dienes by Chain Walking.

Sequential formation of distant bonds in organic molecules was achieved for the palladium-catalyzed hydrosilylation/cyclization of various 1,n-dienes by chain walking of the metal catalyst. The reaction was applicable to various 1,n-dienes, including a 1,13-diene, to form a cyclopentane ring as well as a carbon-silicon bond at a remote site. The use of "nondissociative" chain walking provides a fascinating strategy in organic synthesis to functionalize distant parts of organic molecules, in a particular order, within a catalytic cycle by effectively moving the reactive center from a remote position.

[A Case of Mucinous Cystoadenocarcinoma with Metastatic Liver Tumor in a Young Woman Lacking Specific Findings].

The patient was a 17-year-old woman. An abnormal urinalysis was observed, and abdominal echography showed a pancreatic cystic mass. At the first examination, computed tomography(CT)and endoscopic ultrasound(EUS)showed a unilocular cystic mass of 60mm in size in the pancreatic body and tail, and no malignant findings were observed. After 14 months, CT and positron emission tomography-computed tomography(PET-CT)showed that the cystic mass had a mural nodule with FDG accumulation, and presence of a tumor in hepatic S8 with FDG accumulation. Laparoscopic distal pancreatectomy and hepatic subsegmentectomy of S8 were performed for diagnostic and therapeutic purposes. The pathological diagnosis was mucinous cystadenocarcinoma(MCC)and metastatic liver cancer in the form of MCC. S-1 was administered after surgery. Nine months after resection, multiple metastatic liver tumors were found, and GEM plus nab-PTX was administered. After 2 courses of treatment, the patient is still alive without new lesions.

Chain Walking as a Strategy for Carbon-Carbon Bond Formation at Unreactive Sites in Organic Synthesis: Catalytic Cycloisomerization of Various 1,n-Dienes.

Carbon-carbon bond formation at unreactive sp(3)-carbons in small organic molecules via chain walking was achieved for the palladium-catalyzed cycloisomerization of 1,n-dienes. Various 1,n-dienes (n = 7-14) such as those containing cyclic alkenes, acyclic internal alkenes, and a trisubstituted alkene can be used for the chain-walking cycloisomerization/hydrogenation process, and five-membered ring compounds including simple cyclopentane and pyrrolidine derivatives can easily be prepared. Chain walking over a tertiary carbon was also found to be possible in the cycloisomerization. It is not necessary for the linker portion of the diene to contain a quaternary center, and diene substrates with two alkene moieties linked by a tertiary carbon or a nitrogen atom can also be used as substrates. Column chromatography using silica gel containing silver nitrate was found to be effective for isolating some of the cycloisomerization products without hydrogenation. Deuterium-labeling experiments provided direct evidence to show that the reaction proceeds via a chain-walking mechanism.

Chain-walking strategy for organic synthesis: catalytic cycloisomerization of 1,n-dienes.

The catalytic construction of carbon-carbon bonds in small organic molecules via chain walking is described. Catalytic cycloisomerization of 1,n-dienes via chain walking was achieved using a palladium-1,10-phenanthroline catalyst to form five-membered-ring products. By means of a cycloisomerization/hydrogenation protocol, 1,7- to 1,14-dienes were selectively converted to bicyclo[4.3.0]nonane derivatives. The use of chain walking provides a new method in organic synthesis to functionalize unreactive carbon-hydrogen bonds by letting the catalyst look for preferable bond-forming sites by moving around on the substrate.