Clinical outcomes after pancreaticoduodenectomy in elderly patients at middle-volume center.

BACKGROUND/AIMS: It has been reported that age and hospital volume are risk factors after pancreaticoduodenectomy (PD), however the mortality rate after PD at middle volume center is decreasing by surgical advances and recently PD in the elderly patients is safely performed. The aim of this study is to evaluate the safety and feasibility of PD in the patients over 80 years of age at middle-volume center. METHODOLOGY: 60 patients who underwent PD between 2004 and 2012 were divided into two groups (≥80 and <80years). The clinical outcomes of the two groups were retrospectively analyzed. RESULTS: There were no statistical differences in terms of preoperative parameters, co-morbidity, perioperative data, morbidity, mortality and postoperative hospital stay. We achieved zero mortality in patients over 80 years of age and 40% of them are alive without recurrence. CONCLUSIONS: Clinical outcomes after PD in the elderly patients at middle-volume center are acceptable. Age and hospital volume are not necessarily risk factors after PD.

Usefulness of pyloric reconstruction without compromising curative resection in gastric cancer treatment.

INTRODUCTION: We herein report the short-term results of the newly developed modified technique of Billroth I (modified B-I; pylorus reconstruction) that prevents duodenogastric reflux (DGR) and remnant gastritis after distal gastrectomy. PATIENTS AND METHODS: Distal gastrectomy with this technique was performed in 20 patients (age, 41 to 86 years [mean, 68.5 ± 11.8 years], male/female = 12:8) with gastric cancer from June 2006 through December 2009. These patients were compared with another 20 patients who underwent conventional B-I after distal gastrectomy (age, 41 to 85 years [mean, 69.3 ± 8.69 years], male/female = 11:9). The side effects of gastric surgery evaluated in this study were the degree of remnant gastritis, the presence of dumping syndrome, and the degree of weight loss. RESULTS: By gastrografin contrast imaging on the fifth day after pylorus reconstruction, the remnant stomach was not dilated and gastrografin flowed physiologically to the duodenum without backward reflux into the remnant stomach. By gastroscopy at 6 months after the operation, DGR and the degree of remnant gastritis after pylorus reconstruction was lower than those of conventional B-I (P = 0.00068). The bile acid concentration of remnant gastric juice of pylorus reconstruction was lower than that of conventional B-I (55.5 ± 93.5 vs. 1,369.5 ± 2,502.1 µmol/L, P = 0.0415). Weight loss at 1 year after distal gastrectomy was less in pylorus reconstruction compared with conventional B-I (6.2 ± 5.2% vs. 9.8 ± 8.7%, P = 0.0725). CONCLUSION: Pylorus reconstruction is a simple and safe anastomotic technique that reduces the side effects of B-I reconstruction.

Study of mechanical properties of engineered cartilage in an in vivo culture for design of a biodegradable scaffold.

INTRODUCTION: An engineered trachea with an absorbable scaffold should be used to augment the repair of a stenotic tracheal section in infants and children because this type of engineered airway structure can grow as the child grows. Our strategy for relief of tracheal stenosis is tracheoplasty by engineered cartilage implantation in accordance with the concept of costal cartilage grafting to enlarge the lumen. This study investigated the mechanical properties of regenerative cartilage with a biodegradable scaffold, Neoveil®, to aid in design of a composite scaffold that maintained semi-rigid properties until cartilage could be generated. MATERIALS AND METHODS: New Zealand White rabbit (n=3) chondrocytes were isolated from auricular cartilage with collagenase type 2 digestion. Then 10x10(6)/cm3 chondrocytes in atelocollagen solution were seeded onto polyglycolic acid (PGA) mesh. A total of 36 constructs, 12 from each rabbit, were implanted into athymic mice (3 constructs/mouse). Constructs were retrieved after 8 weeks and evaluated by measurements of mechanical and biochemical properties as well as histological examination. Thirty-six PGA mesh sheets of the same size but without cells were implanted in control mice. RESULTS: After 6 weeks of implantation, staining of sections with Safranin O revealed cartilage accumulation. Glycosaminoglycan was gradually produced from chondrocytes in the engineered constructs, correlating with the duration of implantation. Mechanical parameters had the same values as those for rabbit tracheal cartilage 8 weeks after implantation. CONCLUSIONS: Biodegradable Neoveil® had good biocompatibility and was able to support extracellular matrix formation in engineered cartilage in an animal model.

Disadvantage of operation cost in laparoscopy-assisted distal gastrectomy under the national health insurance system in Japan.

BACKGROUND: The utility and problems including the socioeconomic aspect of laparoscopy-assisted distal gastrectomy for gastric cancer have not been fully evaluated. SUBJECTS AND METHODS: We compared open distal gastrectomy and laparoscopy-assisted distal gastrectomy for the clinical benefit, quality of life, and problems of operation cost by the reference documents in which the difference between open distal gastrectomy and laparoscopy-assisted distal gastrectomy was examined in detail. The reference documents retrieved by the key words 'gastric, cancer, laparoscopic, surgery' were 22 in PubMed with the following limits activated: Humans, Clinical Trial, Meta-Analysis, Randomized Controlled Trial, Review, English, Core clinical journals, published in the last 10 years. RESULTS: The operation time of laparoscopy-assisted distal gastrectomy is longer than that of open distal gastrectomy. However, if skilled, the blood loss of laparoscopy-assisted distal gastrectomy is less, the hospitalization days and the duration of fasting after laparoscopy-assisted distal gastrectomy are shorter than those after open distal gastrectomy. The number of excised lymph nodes and the incidence of postoperative complications were similar between laparoscopy-assisted distal gastrectomy and open distal gastrectomy. On the other hand, in the national health insurance system, the operation fee of open distal gastrectomy was USD 6,637 as compared to USD 7,586 for laparoscopy-assisted distal gastrectomy. In spite of the USD 949 difference in the operation fee, the use of disposable instruments for laparoscopy-assisted distal gastrectomy results in a deficit of USD 1,500 over open distal gastrectomy. CONCLUSION: In spite of the medical superiority of laparoscopy-assisted distal gastrectomy over open distal gastrectomy (if a skilled surgeon operates) as less invasive surgery, laparoscopy-assisted distal gastrectomy is associated with less financial benefit to the hospital as compared to open distal gastrectomy in the current Japanese health insurance system.

An animal model study for tissue-engineered trachea fabricated from a biodegradable scaffold using chondrocytes to augment repair of tracheal stenosis.

INTRODUCTION: We have designed an engineered graft fabricated from a biodegradable scaffold using chondrocytes and applied this construct to augment repair of tracheal stenosis. This study investigated the feasibility of using such tissue-engineered airways with autologous chondrocytes in a rabbit model. MATERIAL AND METHODS: Chondrocytes were isolated and expanded from the auricular cartilage of New Zealand white rabbits, then seeded onto composite 3-layer scaffolds consisting of a collagen sheet, a polyglycolic acid mesh, and a copolymer (l-lactide/epsilon-caprolactone) coarse mesh. The engineered grafts were implanted into a 0.5 x 0.8-cm defect created in the midventral portion of the cervical trachea. Gelatin sponges that slowly released basic fibroblast growth factor (b-FGF) were then placed on the constructs, which were retrieved 1 or 3 months after implantation. RESULTS: The biodegradable scaffold seeded with chondrocytes could maintain airway structure up to 3 months after implantation. Tracheal epithelial regeneration occurred in the internal lumen of this composite scaffold. Three months after implantation, staining of the sections showed cartilage accumulation in the engineered tracheal wall. CONCLUSION: This composite biodegradable scaffold may be useful for developing engineered trachea. A gelatin sponge slowly releasing b-FGF might enhance chondrogenesis.

Human tracheal chondrocytes as a cell source for augmenting stenotic tracheal segments: the first feasibility study in an in vivo culture system.

INTRODUCTION: Construction of engineered respiratory tract using tissue-engineered cartilage has not yet been reported. In order to generate artificial trachea using human chondrocytes obtained from tracheal cartilage, we investigated whether human tracheal chondrocytes can act as a cell source to fabricate engineered airway patches to augment stenotic parts of the trachea. MATERIALS AND METHODS: After informed consent, chondrocytes were obtained from five patients who needed tracheal surgery. A small piece of resected tracheal cartilage was digested by collagenase type 2 for 3-4 h. This yielded chondrocytes, which were expanded in vitro and seeded onto biodegradable scaffolds; these were then implanted subcutaneously in athymic mice. The implanted constructs were retrieved 8 weeks later for histologic and biochemical analysis. RESULTS: In monolayer cultures, chondrocytes proliferated well, showing a 100- to 1,000-fold increase in 1 month. Once expanded, the cells lost their original morphological and biologic characteristics, but the engrafted scaffold showed histologic and biochemical characteristics of cartilage. Viable chondrocytes and extracellular matrix were detected, and glycosaminoglycan (GAG) in vivo was present. CONCLUSIONS: Here we show that a small piece of human tracheal cartilage can generate sufficient chondrocytes in vitro and form tracheal cartilage architecture in an in vivo environment.