Optimization of decellularization methods using human small intestinal submucosa for scaffold generation in regenerative medicine.

Porcine small intestinal submucosa, despite its successful use as a scaffold in regenerative medicine, has innate biomechanical heterogeneity. In this study, we hypothesized that human small intestinal submucosa could be a viable alternative bio-scaffold. For the first time, we characterize submucosal extraction from human small intestine and examine appropriate decellularization methods. In total, 16 human small intestinal submucosal samples were obtained and decellularized using three reported methods of porcine decellularization: Abraham, Badylak, and Luo. For each method, four specimens were decellularized. The remaining four specimens were designated as non-decellularized. We measured the amount of residual DNA and growth factors in decellularized human intestinal samples. Additionally, decellularized human small intestinal submucosa was co-cultured with mouse bone marrow-derived mesenchymal stem cells to examine mesenchymal stem cell survival and proliferation. The reference value for the amount of residual DNA deemed appropriate in decellularized tissue was established as 50 ng/mg of extracellular matrix dry weight or less. Abraham's method most successfully met this criterion. Measurement of residual growth factors revealed low levels observed in samples decellularized using the Abraham and Badylak methods. Co-culture of each small intestinal submucosal sample with mouse bone marrow-derived mesenchymal stem cells confirmed viable cell survival and proliferation in samples derived using protocols by Abraham and Badylak. Abraham's method most successfully met the criteria for efficient tissue decellularization and cell viability and proliferation. Thus, we consider this method most suitable for decellularization of human small intestinal submucosa.

[A Curatively Resected Case of Recto-Sigmoidal Cancer with Massive Bladder Invasion after Multimodal Therapy Including Chemotherapy].

A 68-year-old male patient was referred to our hospital because of unfit to treat his recto-sigmoidal cancer massively invaded to bladder at the former hospital. During drug administration to treat heart failure, we could perform a transverse colostomy and initiated mFOLFOX plus Pmab. During chemotherapy, he improved malnutrition. After 7 courses, CT scan showed a marked reduction in tumor diameter, which was PR. Since his nutritional and heart status were improved, he underwent a high anterior resection with partial bladder resection. Pathological findings showed that a few cancer cells were remained at bladder and bowel wall. He was diagnosed as Stage Ⅱc. His postoperative course was almost uneventful. No symptom of recurrence has been observed at 9 months after surgery without adjuvant chemotherapy.

[A Case of Liver Metastasis of Gastric Cancer Successfully Treated with SOX plus Nivolumab].

An 82-year-old, male. He visited his local doctor with a chief complaint of dyspnea on exertion. Anemia was noted, and upper gastrointestinal endoscopy was performed, which revealed an ulcerative lesion in the gastric antrum. A biopsy revealed Group 5, tub2, and HER2 negative, with PD-L1≥5%. cT3N1H1(M1 HEP), cStage ⅣB was diagnosed based on CT scan showing enlarged #8 lymph node and a single liver metastasis in the 2 cm range in S6 of the liver. The patient was deemed unresectable and was started on SOX plus nivolumab therapy. On day 11 after initiation, the patient had Grade 3 diarrhea by CTCAE v5.0, and S-1 was withdrawn for 3 days, but was administered for 2 courses. CT and MRI after chemotherapy showed shrinkage of both the primary tumor and liver metastases; R0 resection was deemed possible, and pyloric gastrectomy, D2 lymph node dissection, and partial hepatic S6 resection were performed. The histological evaluation of response to treatment was Grade 1b, and the patient was in ypStage ⅠA. The patient has been alive without recurrence for 6 months postoperatively while receiving S-1 monotherapy on an outpatient basis.

[Long-Term Survival following Multidisciplinary Therapy for Unresectable Pancreatic Body Cancer].

A 57-year-old man was diagnosed with a tumor in the pancreatic body at a nearby hospital and consulted our hospital. Examinations revealed that carbohydrate antigen 19-9(CA19-9)levels were 1,765.0 U/mL. We confirmed metastatic liver tumors in S4 and S8 of the liver by EOB-MRI. We diagnosed unresectable pancreatic cancer(T3N0M1, cStage Ⅳ)and administered 10 courses of gemcitabine(GEM)plus nab-paclitaxel(nab-PTX)therapy. The main lesion and the lesion in S4 subsequently disappeared, and the lesion in S8 degenerated into a cyst. CA19-9 levels were 113 U/mL. Surgery was determined as the best course of action after normalizing CA19-9 levels. Therefore, we further administered 6 courses of FOLFIRINOX therapy and 4 courses of GEM plus nab-PTX therapy, but CA19-9 was not normalized. We decided that it would be difficult to normalize CA19-9, and thus proceeded with surgery. During the operation, cystic degenerative lesions were found in S8 and peritoneal dissemination was found in the transverse mesentery. Because the ascites cytopathology was negative, it was judged that the peritoneal dissemination was localized. We performed distal pancreatectomy(D2)plus partial hepatectomy(S8)plus peritoneal dissemination resection. On day 52 after surgery, we resumed GEM plus nab-PTX. The patient has survived without any recurrence for 3 years after the initial surgery.

[A Case of Pancreas Neuroendocrine Carcinoma Achieved Long-Term Survival by Carboplatin plus Etoposide Therapy].

A 70-year-old man with the history of diabetes mellitus complained of lower abdominal discomfort. Abdominal ultrasonography revealed a pancreatic mass. Contrast enhanced CT showed a 2.6 cm-enhanced tumor ventral to the pancreatic head. It was diagnosed with a pancreatic neuroendocrine carcinoma(PanNEC-G3)by EUS-FNA. The patient underwent pancreatoduodenectomy with the wedge resection of the portal vein and partial resection of the transverse colon. We administered 6 cycles of adjuvant therapy with CDDP plus CPT-11. With the presentation of lymph node metastases and the local recurrence in the anastomotic site of the transverse colon 15 months after surgery, the patient received carboplatin plus etoposide(CE)therapy. Although local recurrence completely responded to the CE therapy, bone metastases were detected 27 months after surgery. Metastatic lesion did not respond to systemic chemotherapy including gemcitabine plus nab-paclitaxel and nal-IRI plus 5-FU/LV, and the patient eventually died 37 months after the surgery. PanNECs represent for less than 1% of all pancreatic tumor. They are characterized by high malignant potential and short time survival with the reported OS of 8.5 to 21 months. This case served as an important reminder to consider multimodal treatment for PanNEC patients to obtain longer survival.

[Three Cases of Lower Advanced Rectal Cancer Involving Pathological Complete Response after Neoadjuvant Chemoradiotherapy].

Neoadjuvant chemoradiotherapy(NACRT)was administered at our hospital to 3 patients with lower advanced rectal cancer; NACRT resulted in pathological complete response(pCR). Case 1: A 65-year-old man was diagnosed with T4aN1M0, cStage Ⅲb disease; after chemoradiotherapy(CRT), the clinical stage improved to T4aN0M0, ycStage Ⅱb. Laparoscopic Hartmann's procedure and D3 lymph node dissection were performed 51 days after CRT. No recurrence was observed 31 months after surgery. Case 2: A 67-year-old man was diagnosed with T4aN2M0, cStage Ⅲb disease; after CRT, the clinical stage improved to T4aN1M0, ycStage Ⅲa. Laparoscopic abdominoperitoneal resection and D3 lymph node dissection were performed 57 days after CRT. No recurrence was observed 21 months after surgery. Case 3: An 83-year-old woman was diagnosed with T4aN2M0, cStage Ⅲb disease; after CRT, the clinical stage improved to T4aN0M0, ycStageⅡb. Laparoscopic abdominoperitoneal resection and D3 lymph node dissection were performed 64 days after CRT. No recurrence was observed 16 months after surgery. Here, we report 3 cases of lower advanced rectal cancer involving curative resection following CRT, and we provide a short literature review.

[A Case of Esophageal Neuroendocrine Carcinoma(NEC)Treated with Collective Treatment].

A 68-year-old man presented to our hospital. An upper gastrointestinal tract endoscopy performed elsewhere revealed an elevated lesion with a circumferential esophageal cancer(identified as small cell carcinoma). Perthe treatment forsmall cell cancer and the standard treatment for esophageal neuroendocrine carcinoma, 7 courses of CBDCA(5mg/m2)plus ETP (100mg/m2)were administered. The lesion shrank and the lymph node swelling disappeared and the patient was deemed to be in partial remission. Nine months later, however, the primary tumor increased in size. A transthoracic subtotal esophagectomy( laparoscope-assisted), 2 area dissection, and gastric tube reconstruction(post-sternal)were performed at 2 years and 10 months afterdiagnosis.

[A Case of Long-Term Survival with Far Advanced Gastric Cancer after Multidisciplinary Treatments, including Conversion Surgery].

An 82-year-old man with Stage Ⅳ advanced gastric cancer and multiple liver metastases was referred to our hospital. Chemotherapy using S-1 was administered, resulting in withdrawal from the usual course because of an adverse event of grade 4 anorexia. GIS and EOB-MRI showed a prominent tumor reduction in both lesions; however, despite this, distal gastrectomy, D2 lymph node dissection, liver biopsy for S3 lesion, partial liver resection for S6 lesion, and cholecystectomy were performed to obtain a therapeutic diagnosis. Pathology revealed that the tumor cells remained in the main liver metastatic lesions. Therapeutic effect was assessed as Grade 2. Although weekly paclitaxel followed by reduced S-1 dosage was introduced after surgery, the recurrent mass was observed in the para-aortic region after 2 years. Subsequently, para-aortic lymph node dissection was performed because no new lesion was detected. More than 10 years have passed without any recurrence since the first surgery. As part of a multidisciplinary treatment for far advanced gastric cancer with multiple liver metastases (Stage Ⅳ), conversion surgery might be considered effective.

[A Resected Case of Rectal Metastasis from Gastric Cancer].

An 82-year-oldwoman previously underwent total gastrectomy for gastric cancer at the age of 75 years. After 7 years of follow-up, a colonoscopy was performedto investigate the cause of constipation, which revealedan irregularity in the rectal submucosa. A colonoscopy-guidedbiopsy showedpoorly differentiatedad enocarcinoma, andthe immunohistochemical staining pattern showedMUC2(-), MUC5AC(+), CDX2(+), andCA1 25(-). FDG-PET showedintense uptake only at the rectum. Thus, laparoscopic high anterior resection was performed. Pathological findings showed that poorly differentiated adenocarcinoma and signet-ring cell carcinoma hadd evelopedmainly in the submucosa. In comparison with the immunohistological features of the previous gastric cancer, the rectal tumor hadsimilar morphological characteristics. The definitive diagnosis was rectal metastasis from gastric cancer. She has remained recurrence-free in the 20 months since this operation.

[HER2-Positive Advanced Gastric Cancer with Para-Aortic Lymph Node Metastases Treated with Conversion Surgery after Chemotherapy-A Case Report].

A 56-year-old woman diagnosed with type 2 gastric cancer and multiple lymph node metastases(T3N3M1[lym], cStage Ⅳ)was treated with chemotherapy using trastuzumab with S-1 plus cisplatin for 6 cycles. The primary lesion showed PR, and lymph node metastases disappeared after the chemotherapy. Because of adverse events, she was administered with 2 additional cycles of trastuzumab with S-1 plus cisplatin and 6 cycles of trastuzumab with capecitabine plus oxaliplatin. However, the primary lesion increased in size. Therefore, she underwent distal gastrectomy and D1+ lymphadenectomy with para-aortic lymph node sampling as a conversion surgery. The pathological diagnosis was T2N0M0, pStage ⅠB, and the primary cancer was Grade 1a owing to the chemotherapeutic effect. She survives without recurrence or postoperative adjuvant therapies 3 years after the surgery.

[A Case of Far-Advanced Esophageal Cancer with Multiple Metastases Showing Long-Term Survival after Chemotherapy].

A 71-year-oldman with voice hoarseness was referredto our hospital for further examination. He was diagnosedwith unresectable Stage Ⅳb esophageal cancer, with direct invasion to the aorta andtrachea andmultiple metastases to the lymph nodes, lungs, and adrenal gland. Because his performance status(PS)was deemedto be favorable, he receivedchemotherapy with docetaxel(DOC), cisplatin, and5 -FU(DCF therapy). After 2 cycles of DCF therapy, the primary lesion was scarred. No malignant lesions were detected in the biopsy performed. No distant metastases were identified on PET-CT. As a subsequent treatment, S-1 plus DOC therapy was administered. Finally, single S-1 administration was continued. The treatment periodwas 14 months. Treatment was concludedbecause a complete response(CR)was maintained. Three years after the conclusion of treatment, CR remains maintained. The overall survival in cases of unresectable advanced esophageal cancer is saidto be 3-10 months, but there are remarkable cases such as this one. If a goodPS is maintained, treatment shouldbe actively considered because CR is possible.

[Three Cases of Decompression Failure in Colon Stent Placement for Obstructive Colorectal Cancer].

Forty-four patients underwent decompression using a self-expandable metallic stent for obstructive colorectal cancer as a bridge to surgery in our department. Three failure cases were examined. Case 1: A Rs, Ra type 2 cancer was treated with WallflexTM 60 mm. Enough decompression could not be obtained, and an additional stent was placed. Consequently, the patient underwent a transverse colostomy. Case 2: A Ra type 2 cancer was treated with Niti-S 60 mm. The patient's chief complaint was not improved due to the tumor ingrowth. Consequently, he underwent a transverse colostomy. Case 3: A sigmoid type 2 cancer was treated with Niti-S 80 mm. Decompression was successful. However, CT scan revealed another tumor in the descending colon. He underwent a transverse colostomy for further examination. The causes of the failure differed in each case. We gained many learning points from these cases that are useful for future treatment.

Perioperative Predictive Markers for Recurrence of Esophageal Cancer after Esophagectomy.

INTRODUCTION: We studied whether perioperative nutritional, immunological factors or postoperative inflammatory responses predicted esophageal cancer (EC) progression and prognosis in patients who received esophagectomies. METHODS: We evaluated preoperative prognostic nutritional index (PNI), BMI, neutrophil-to-lymphocyte ratio (NLR), intraoperative blood loss, postoperative C-reactive protein (CRP) max, recurrence-free survival (RFS), and overall survival (OS) in 111 patients with pStage I-IV squamous cell EC who received esophagectomies. Optimal cutoff values for each continuous parameter were determined by receiver operating characteristic curves and Youden indices. Univariate and multivariate Cox analyses were used to derive independent prognostic factors. Propensity score matching using inverse probability of treatment weighting was used in groups divided by Youden indices, as appropriate. RESULTS: Cutoff values of continuous variables were NLR: 2.27, PNI: 44.2, blood loss: 159 mL, and CRPmax: 21.7 mg/dL. In multivariate analyses, PNI, CRPmax, and intraoperative blood loss were independent prognostic factors for OS and RFS. Among patients with stage II-IV disease, low PNI was associated with shorter RFS. Postoperative respiratory complications were associated with both higher CRP and shorter RFS. DISCUSSION/CONCLUSIONS: Low preoperative PNI and high postoperative inflammatory response were associated with postoperative EC progression after esophagectomy. Preoperative nutritional interventions or suppression of postoperative inflammatory response, including respiratory complications, may improve patient prognosis.

Successful treatment of gastric cancer after complete response of lung cancer by nivolumab: a case report.

BACKGROUND: Nivolumab is effective for gastric cancer and lung cancer, but complete response is rare. We experienced a case of synchronous gastric cancer and lung cancer who was treated by nivolumab and laparoscopic gastrectomy. CASE PRESENTATION: A 63-year-old male consulted our institution and was found to have gastric cancer cT1(SM)N0M0 Stage IA and lung cancer cT2N2M1(PUL) Stage IV. He received eight chemotherapy treatments plus radiation, but the lung disease remained progressive. Finally, he received nivolumab therapy and complete response of both cancers was obtained. The gastric cancer recurred, but was successfully treated by laparoscopic gastrectomy. The resected specimen revealed three lesions, each being pT1aN0M0 Stage IA. The primary gastric cancer seemed to have completely vanished without scarring. CONCLUSIONS: This was thought to be a rare case of gastric cancer recurrence after complete response of gastric cancer and lung cancer to nivolumab.

Laparoscopic treatment of median arcuate ligament syndrome in a 16-year-old male.

INTRODUCTION: MALS(Median Arcuate Ligament Syndrome) is rare disease. We experienced the case of MALS and successfully treated by laparoscopic approach. PRESENTATION OF CASE: A 16-year-old male was admitted to our hospital with postprandial epigastric pain that had been present for 3 years. Abdominal three-dimensional computed tomographic angiography showed stenosis of the celiac trunk, and abdominal Doppler ultrasonography showed that the blood flow in the celiac trunk varied between inspiration and expiration. Hence, the patient was diagnosed with median arcuate ligament syndrome. Laparoscopic decompression of the celiac trunk was performed by division of the ligament and partial excision of the celiac plexus. Intraoperative Doppler ultrasonography showed markedly improved flow in the celiac artery. The patient was discharged from hospital on postoperative day 7, and has no recurrent symptoms at 12 months postoperatively. DISCUSSION: This case was most youngest male MALS treated by laparoscopic approach. CONCLUSION: Laparoscopic division of the median arcuate ligament is a minimally invasive, safe, and effective method for decompression of the celiac artery.