[A Case of Conversion Surgery for Gallbladder Cancer with Para-Aortic Lymph Node Metastasis].

The study presents the case of a 71-year-old woman who visited a nearby hospital for epigastric pain and weight loss. A CT scan showed a mass in the gallbladder, and the CEA level was high, so she was referred to our hospital for further investigation. Abdominal US, CT, and MRI suggested gallbladder cancer with para-aortic metastasis, and the histological findings on the EUS-FNA confirmed the diagnosis. Since surgical resection was not indicated, chemotherapy was performed(gemcitabine plus cisplatin). After 10 courses of chemotherapy, CT and MRI showed downsizing of para-aortic lymph nodes, and no accumulation of FDG was found on FDG-PET. Confirming the downstaging of cancer, conversion surgery, comprising an extended cholecystectomy and a lymph node resection, was performed. The pathological diagnosis showed no lymph node metastasis. No recurrence was observed after 12 months of surgery. Initially, unresectable gallbladder cancer with para-aortic lymph node metastasis was indicated to be compatible with preoperative chemotherapy and conversion surgery.

[A Case of Cardiac Tamponade during Multimodal Treatment for Mediastinal Lymph Node Metastasis of Gastric Cancer].

A 52-year-old man underwent total gastrectomy for gastric cancer and chemoradiotherapy for thoracic paraaortic lymph node metastasis. He also underwent esophageal stent implantation for stenosis. He was admitted to our hospital with fever and breathing difficulty and was diagnosed with infectious pericarditis. He showed symptoms of shock due to cardiac tamponade. After pericardial drainage, his vital signs improved. When signs of infection are detected in patients with a history of chemoradiotherapy or stent implantation, we should consider infectious pericarditis due to esophageal pericardial fistula and apply immediate drainage of cardiac tamponade.

[A Case of Long-Term Progress Control of Unresectable Progressive Gastric Cancer with Nivolumab Introduced during Effective Duration of Secondary Treatment].

A 65-year-old man with 1 month of general malaise was admitted to our hospital. Thoracoabdominal CT showed that the supra-clavicular, sub-carina, and para-aortic lymph nodes were swelling. Upper gastrointestinal endoscopy revealed 2 type 1 tumors at the esophagogastric junction, and the biopsy showed Group 5, well to moderately differentiated adenocarcinoma. The clinical diagnosis was cardiac gastric cancer and cStage Ⅳ(cT3N3M1[LYM]). We started capecitabine plus oxaliplatin as the first-line chemotherapy, and weekly paclitaxel plus ramucirumab was administered as the second-line treatment. The second-line treatment was successful, and the effect of PR was obtained. However, considering the period of TTF, while the therapeutic effect continued, we switched to third-line treatment with nivolumab after 7 courses of the second treatment. With the third-line treatment, PR was maintained for 1 year and 3 months, and good quality of life and performance status were obtained for a long period without irAE. However, after 32 courses, because the tumor marker was elevated and lymph nodes were enlarged, we judged PD and switched to the fourth-line treatment with nab-paclitaxel plus ramucirumab. The tumor marker levels decreased, the lymph nodes shrank, and PR was achieved again with the fourth-line treatment. The treatment is still ongoing 2 year and 8 months after the diagnosis.

[Two Cases of Large Gastrointestinal Stromal Tumors Safely and Completely Resected by Laparoscopic Surgery Followed by Neoadjuvant Imatinib Therapy].

Case 1, the patient was a 51-year-old man. Upper gastrointestinal endoscopy revealed a submucosal tumor with delle at the posterior wall of the gastric body, and the biopsy demonstrated a diagnosis of GIST. Abdominal CT scan showed a tumor at the size of 130×110×90 mm. Six months after administration of 400 mg/day of imatinib, the maximum diameter was reduced to 55 mm, then partial gastrectomy was performed by laparoscopic surgery. He continued to take imatinib after the surgery for 3 years, and he is alive without recurrence 4 years postoperatively. Case 2, the patient was a 68-year-old man. An abdominal CT scan showed a tumor at the size of 160×120×85 mm on the posterior outside of the stomach, but no submucosal tumor could be identified by upper gastrointestinal endoscopy. Gastric GIST was suspected and he started taking imatinib 400 mg/day. Because the Grade 3 generalized eruption was appeared, imatinib was discontinued, and then the dose was reduced. Nine months after the initiation of the treatment, the maximum diameter was reduced to 90 mm, and laparoscopic partial gastrectomy was performed. The patient is followed up without administration of imatinib after the surgery, and is alive without recurrence for 1 year and 6 months postoperatively. We report 2 cases that the large gastric GIST was able to be resected safely and completely due to tumor shrinkage by neoadjuvant imatinib therapy.

[A Case of Hepatocellular Carcinoma with Extrahepatic Growth-A Difficult Preoperative Diagnosis].

A 75-year-old man was admitted to our hospital for breathing difficulty. CT showed a 20 cm mass with clear boundaries and internal non-uniformity, which we suspected to be a gastrointestinal stromal tumor(GIST). Surgical resection was been considered to be risky because the mass was close to surrounding organs, such as the stomach, liver and diaphragm. Thus, we chose imatinib therapy. After 2 months, he was admitted to our hospital for anemia. CT showed the size of mass to be smaller, but the area of low density with internal non-uniformity had increased. We diagnosed intratumoral bleeding, and chose surgical resection. The mass was under the omentum, and had infiltrated the extrahepatic area and lesser curvature of the stomach. We diagnosed the mass derived from the stomach, and performed partial gastrectomy with partial liver resection. Pathological diagnosis was extrahepatically growing hepatocellular carcinoma(HCC, pT3N0M0, pStage Ⅲ).

[Two Cases of Resectable Gastric Cancer with Extensive Nodal Metastasis That Received Preoperative DOS Therapy].

Case 1: A 67-year-old male had a type 1 tumor in the stomach with a lymph node metastasis 50 mm in size. He was diagnosed with cT4aN(+)M0, cStage Ⅲ and received preoperative docetaxel plus oxaliplatin plus S-1(DOS)therapy. After 3 courses of the regimen, the patient underwent laparoscopic total gastrectomy. The final stage was ypT3N1(1/38) M0, ypStage ⅡB, R0, and the pathological response was Grade 2b. Case 2: A 64-year-old male had a type 3 tumor in the abdominal esophagus and a lymph node metastasis 15 mm in size. He was diagnosed with cT3N(+)M0, cStage Ⅲ and received preoperative DOS therapy. After 3 courses, he underwent laparoscopic esophagectomy. The final stage was ypT0N0M0, ypStage 0, R0, and the pathological response was Grade 3. DOS therapy may be effective as a neoadjuvant chemotherapy.

[A Case of Pancreatic Pseudocyst Recurrence after Surgery for Remnant Pancreatic Cancer].

The patient was a 72-year-old man with a history of pancreatic cancer and IPMA treated with distal pancreatectomy. He had recurrence-free period after adjuvant chemotherapy with S-1. But 6 years after the surgery, a diameter of 1 cm mass was noted in the remnant pancreas on MRI examination after hepatocellular carcinoma treatment. The mass was diagnosed as remnant pancreatic cancer, and he had undergone partial pancreatectomy of remnant pancreas. The pathological diagnosis was pancreatic ductal carcinoma with negative margin. However, 6 months after the reoperation, epigastric pain appeared, and CT scan showed a pseudocyst of 10 cm in size. The diagnosis was local recurrence with positive cytology, and then puncture drainage was performed. After repeated drainages, adhesion of the cystic lesion, and chemotherapy, the cytology became negative and the cystic lesion disappeared, but peritoneal dissemination metastasis also appeared. The patient died of the primary disease 7 years and 8 months after the first surgery and 1 year and 11 months after the second surgery. There has been no report of local recurrence in the form of pancreatic pseudocyst after pancreatic cancer surgery, and we report this case with literature discussion.

C5-symmetric chiral corannulenes: desymmetrization of bowl inversion equilibrium via "intramolecular" hydrogen-bonding network.

Because of a rapid conformational inversion, bowl-shaped C5-symmetric corannulenes, though geometrically chiral, have not been directly resolved into their enantiomers. However, if this inversion equilibrium can be desymmetrized, chiral corannulenes enriched in either enantiomer can be obtained. We demonstrated this possibility using pentasubstituted corannulenes 4 and 5 carrying amide-appended thioalkyl side chains. Compound 4 displays chiroptical activity in a chiral hydrocarbon such as limonene. Because compound 5 carries a chiral center in the side chains, its enantiomers 5R and 5S show chiroptical activity even in achiral solvents such as CHCl3 and methylcyclohexane. In sharp contrast, when the side chains bear no amide functionality (1 and 2R), no chiroptical activity emerges even in limonene or with a chiral center in the side chains. Detailed investigations revealed that the peripheral amide units in 4 and 5 are hydrogen-bonded only "intramolecularly" along the corannulene periphery, affording cyclic amide networks with clockwise and anticlockwise geometries. Although this networking gives rise to four stereoisomers, only two, which are enantiomeric to one another, are suggested computationally to exist in the equilibrated system. In a chiral environment (chiral solvent or side chain), their thermodynamic stabilities are certainly unequal, so the bowl-inversion equilibrium can be desymmetrized. However, this is not the case when the system contains a protic solvent that can deteriorate the hydrogen-bonding network. When the enantiomeric purity of limonene as the solvent is varied, the chiroptical activity of the corannulene core changes nonlinearly with its enantiomeric excess (majority rule).