Hypoxia at 3D organoid establishment selects essential subclones within heterogenous pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is especially hypoxic and composed of heterogeneous cell populations containing hypoxia-adapted cells. Hypoxia as a microenvironment of PDAC is known to cause epithelial-mesenchymal transition (EMT) and resistance to therapy. Therefore, cells adapted to hypoxia possess malignant traits that should be targeted for therapy. However, current 3D organoid culture systems are usually cultured under normoxia, losing hypoxia-adapted cells due to selectivity bias at the time of organoid establishment. To overcome any potential selection bias, we focused on oxygen concentration during the establishment of 3D organoids. We subjected identical PDAC surgical samples to normoxia (O2 20%) or hypoxia (O2 1%), yielding glandular and solid organoid morphology, respectively. Pancreatic cancer organoids established under hypoxia displayed higher expression of EMT-related proteins, a Moffitt basal-like subtype transcriptome, and higher 5-FU resistance in contrast to organoids established under normoxia. We suggest that hypoxia during organoid establishment efficiently selects for hypoxia-adapted cells possibly responsible for PDAC malignant traits, facilitating a fundamental source for elucidating and developing new treatment strategies against PDAC.

Free-Viewpoint Video in Open Surgery: Development of Surgical Arena 360.

OBJECTIVE: We aimed to apply the free-viewpoint video technology developed and introduced mainly for sports spectators to an open surgical video recording system. DESIGN: Prospective feasibility study. SETTING: University of Tsukuba Hospital, Ibaraki, Japan. PARTICIPANTS: Patients who underwent open pancreaticoduodenectomy for pancreatic cancer between December 2022 and March 2023 were included. The gastrojejunal anastomosis was the subject of the recording. RESULTS: Four surgeries were recorded with Surgical Arena 360, which is the free-viewpoint video system that we developed. The feasibility of performing a series of surgical procedures without interrupting the surgeon's line of sight or manipulation was demonstrated in all cases. CONCLUSIONS: Our study revealed that Surgical Arena 360, an open surgical video recording system developed by applying free-viewpoint video technology, can provide new insights into surgical support and clinical knowledge to surgeons by enabling secure capture of the open surgical field from multiple angles.

A comparative study of stoma-related complications from diverting loop ileostomy or colostomy after colorectal surgery.

PURPOSE: Even though minor, stoma-related complications significantly impact quality of life, they are often excluded from clinical analyses that compare short-term postoperative outcomes of loop ileostomy and loop colostomy. This study compares stoma-related complications between loop ileostomy and loop colostomy after rectal resection, including minor complications, and discusses the characteristics of diverting stoma types. METHODS: A retrospective review was conducted in patients who underwent diverting stoma construction after rectal resection. Data on patient background and postoperative short-term outcomes, including stoma-related complications and morbidity after stoma closure, were collected and compared between loop ileostomy and loop colostomy groups. Morbidities of all severity grades were targeted for analysis. RESULTS: A total of 47 patients (27 loop ileostomy, 20 loop colostomy) underwent diverting stoma construction following rectal resection. Overall stoma-related complications, incidence of skin irritation, high-output stoma, and outlet obstruction were significantly higher in the loop ileostomy group but high-output stoma and outlet obstruction were absent in the loop colostomy group. Regarding morbidity after stoma closure, operation times and surgical site infections were significantly higher in the loop colostomy group while anastomotic leakage after diverting stoma closure occurred (2 cases; 15%) in the loop colostomy group but not the loop ileostomy group. CONCLUSION: Because stoma-related complications were significantly higher in the loop ileostomy group, and even these minor complications may impair QOL, early loop ileostomy closure is recommended. For loop colostomy, stoma-related morbidities are lower but post-closure leakage is a calculated risk.

Splenic artery transposition for reconstruction of a large hepatic artery aneurysm: A case report and literature review.

INTRODUCTION AND IMPORTANCE: Hepatic artery aneurysms (HAAs) are rare. Typical treatment options for HAAs are surgical resection and endovascular treatment but treatment choices remain controversial. CASE PRESENTATION: A 65-year-old woman was rushed to our hospital suspected to have hemorrhage. Contrast-enhanced CT showed a large 12 cm aneurysm of the common hepatic artery (CHA). We diagnosed duodenal hemorrhage due to imminent rupture of the HAA. Angiography was first performed. The inferior pancreaticoduodenal artery was embolized with a coil under interventional radiology technique for arterial bleeding control. Next, we performed resection of the aneurysm and total pancreatectomy with splenic artery reservation. We reconstructed via splenic artery transposition because of the reconstruction distance, vascular system, and stability of the anastomosis. The patient was discharged from the hospital on postoperative day 21 without any complications. CLINICAL DISCUSSION: There are two key points in this report. Firstly, the choice of splenic artery transposition is optimal for caliber difference and reconstruction distance. The choice of splenic artery should be considered a reliable option. Secondly, total pancreatectomy avoids exposure to pancreatic juice at the anastomosis site due to pancreatic fistula. CONCLUSION: Splenic artery transposition for HAA is advantageous in adjustability of the caliber difference and securing of sufficient distance. In addition, total pancreatectomy may be acceptable in patients with a normal pancreas to avoid fatal complications such as disruption of the anastomosis and reconstructed artery due to pancreatic juice exposure.

Intussusception induced by gastrointestinal metastasis of malignant melanoma: A case report.

INTRODUCTION: Malignant melanoma sometimes metastasizes to small intestine, and could cause various clinical symptoms, including intussusception. Among the acute abdomen cohort in Japan, it is quite rare to encounter this entity. PRESENTATION OF CASE: A 68-year-old male patient was admitted to our hospital with chief complaints of abdominal pain and vomiting.　He underwent tumor resection for malignant melanoma of the primary lesion at left foot base, local recurrence and brain metastasis during the last five years. At admission, abdominal X-ray demonstrated small bowel obstruction. An ileus tube was inserted, and contrast media enema study showed crab-like shadow defect was observed in the advanced part. Enhanced computed tomography showed intussusception in the proximal jejunum caused by a tumor of 5 cm in diameter in the advanced part. No other intestinal lesion was found. Diagnosis of intussusception caused by solitary metastasis of malignant melanoma was made. Laparoscopic partial resection of the small intestine was performed. Postoperative course was uneventful, and patient was followed in outpatient clinic without further treatment with any recurrence of disease for one years. DISCUSSION: Malignant melanoma tends to metastases to the small intestine simultaneously and multiply. It bothers surgeons to decide range of small intestinal resection at emergency surgery. In the present study, preoperative examination allowed the adequate range of intestinal resection including location and number of metastases before operation. CONCLUSION: When an acute abdomen caused by intestinal metastasis of malignant melanoma was consulted, surgeon should make effort to identify location and number of metastatic lesion, preoperatively.