Feasibility of full-thickness gastric resection using master and slave transluminal endoscopic robot and closure by overstitch: a preclinical study

Background

Gastric submucosal tumors are often treated by laparoscopic wedge resection. This study aimed to examine the feasibility of gastric full-thickness resection through a totally endoscopic approach using the master and slave transluminal endoscopic robot (MASTER), and closure of the luminal defect with an endoscopic suturing device.

Methods

The operation was performed in two live porcine models under general anesthesia. First, the anterior wall of the stomach was slung to the abdominal wall using a percutaneous suturing device. An imaginary 5-cm lesion was marked using a needle knife. After the initial mucosal incision was made using an IT knife, the MASTER was introduced through a long overtube. A circumferential mucosal incision was completed with the MASTER to expose the muscularis propria which was grasped and incised to the serosal layer by electrocautery applied through the hook of the MASTER. The full-thickness resection of the gastric wall was completed with retraction using the grasper and dissection using the hook. While the defect was being created, the luminal space was maintained with traction of the percutaneous sutures. The defect was closed with suture plication using an Apollo Overstitch device.

Results

Two full-thickness gastric resections were performed in two nonsurvival porcine models (body weight = 30 and 35 kg, respectively) using the MASTER. The total procedure time was 56 min for the first model and 70 min for the second model. The luminal view was maintained during the whole procedure, and there was no damage to surrounding organs throughout the whole procedure. The gastric defects were closed successfully using Overstitch, with satisfactory gastric distension and no gas leakage afterward.

Conclusion

The current experiment demonstrated the feasibility and safety of a totally endoscopic approach for the treatment of gastric submucosal tumors: full-thickness resection with the MASTER and successful closure of the defect using Overstitch.     

In vivo tissue engineering of an adipose tissue flap using fat grafts and Adipogel

For decades, plastic surgeons have spent considerable effort exploring anatomical regions for free flap design. More recently, tissue‐engineering approaches have been utilised in an attempt to grow transplantable tissue flaps in vivo. The aim of this study was to engineer a fat flap with a vascular pedicle by combining autologous fat grafts and a novel acellular hydrogel (Adipogel) in an established tissue‐engineering model comprising a chamber and blood vessel loop. An arteriovenous loop was created in the rat groin from the femoral vessels and positioned inside a perforated polycarbonate chamber. In Group 1, the chamber contained minced, centrifuged autologous fat; in Group 2, Adipogel was added to the graft; and in Group 3, Adipogel alone was used. Constructs were histologically examined at 6 and 12 weeks. In all groups, new tissue was generated. Adipocytes, although appearing viable in the graft at the time of insertion, were predominantly nonviable at 6 weeks. However, by 12 weeks, new fat had formed in all groups and was significantly greater in the combined fat/Adipogel group. No significant difference was seen in final construct total volume or construct neovascularisation between the groups. This study demonstrated that a pedicled adipose flap can be generated in rats by combining a blood vessel loop, an adipogenic hydrogel, and a lipoaspirate equivalent. Success appears to be based on adipogenesis rather than on adipocyte survival, and consistent with our previous work, this adipogenesis occurred subsequent to graft death and remodelling. The regenerative process was significantly enhanced in the presence of Adipogel.     

A survey of FRAXE allele sizes in three populations

FRAXE is a fragile site located at Xq27-8, which contains polymorphic triplet GCC repeats associated with a CpG island. Similar to FRAXA, expansion of the GCC repeats results in an abnormal methylation of the CpG island and is associated with a mild mental retardation syndrome (FRAXE-MR). We surveyed the GCC repeat alleles of FRAXE from 3 populations. A total of 665 X chromosomes including 416 from a New York Euro-American sample (259 normal and 157 with FRAXA mutations), 157 from a Chinese sample (144 normal and 13 FRAXA), and 92 from a Finnish sample (56 normal and 36 FRAXA) were analyzed by polymerase chain reaction. Twenty-seven alleles, ranging from 4 to 39 GCC repeats, were observed. The modal repeat number was 16 in the New York and Finnish samples and accounted for 24% of all the chromosomes tested (162/665). The modal repeat number in the Chinese sample was 18. A founder effect for FRAXA was suggested among the Finnish FRAXA samples in that 75% had the FRAXE 16 repeat allele versus only 30% of controls. Sequencing of the FRAXE region showed no imperfections within the GCC repeat region, such as those commonly seen in FRAXA. The smaller size and limited range of repeats and the lack of imperfections suggests the molecular mechanisms underlying FRAXE triplet mutations may be different from those underlying FRAXA. © 1996 Wiley-Liss, Inc.     

Neoadjuvant and Adjuvant Systemic Therapy for Newly Diagnosed Stage II–IV Epithelial Ovary,Fallopian Tube,or Primary Peritoneal Carcinoma: A Practice Guideline

Background: This study aims to provide guidance for the use of neoadjuvant and adjuvant systemic therapy in women with newly diagnosed stage II–IV epithelial ovary, fallopian tube, or primary peritoneal carcinoma. Methods: EMBASE, MEDLINE, and Cochrane Library were investigated for relevant systematic reviews and phase III trials. Articles focusing on consolidation and maintenance therapies were excluded. Results: For women with potentially resectable disease, primary cytoreductive surgery, followed by six to eight cycles of intravenous three-weekly paclitaxel and carboplatin is recommended. For those with a high-risk profile for primary cytoreductive surgery, neoadjuvant chemotherapy can be an option. Adjuvant chemotherapy with six cycles of dose-dense weekly paclitaxel plus three-weekly carboplatin can be considered for women of Japanese descent. In women with stage III or IV disease, the incorporation of bevacizumab concurrent with paclitaxel and carboplatin is not recommended for use as adjuvant therapy unless bevacizumab is continued as maintenance therapy. Intravenous paclitaxel plus intraperitoneal cisplatin and paclitaxel can be considered for stage III optimally debulked women who did not receive neoadjuvant chemotherapy. However, intraperitoneal administration of chemotherapy with bevacizumab should not be considered as an option for stage II–IV optimally debulked women. Discussion: The recommendations represent a current standard of care that is feasible to implement and valued by both clinicians and patients.     

Combining Analysis of Tumor-infiltrating Lymphocytes (TIL) and PD-L1 Refined the Prognostication of Breast Cancer Subtypes

BackgroundPD-L1 has been used as a biomarker to select patients for treatment of PD-1/PD-L1 inhibitors.Materials and MethodsIn this study, we assessed the clinicopathological features of breast cancers that are associated with PD-L1 expression, as well as its relationship with other immune components and its prognostic significance.ResultsTotally 1752 cases were included in this cohort. PD-L1 expression in tumor-infiltrating immune cells (PD-L1-IC) expression and in tumor cells (PD-L1-TC) expression were identified in 34.2% and 10.1% of cases, respectively, and they showed a positive correlation with higher tumor grade, morphological apocrine features, presence of necrosis, and higher stromal tumor-infiltrating lymphocytes (sTIL). PD-L1-IC and PD-L1-TC expression correlated positively with each other, and both of them were negatively associated with estrogen receptor and progesterone receptor and positively associated with Ki67, HER2, EGFR, p63, and p-cadherin. In survival analysis, PD-L1-IC expression was associated with better disease-free survival (DFS) and breast cancer-specific survival (BCSS) in HER2-overexpressed (HER2-OE) cancers and high–grade luminal B cancers. In triple–negative breast cancers (TNBC) and HER2–OE cancers, compared with sTIL low PD-L1-IC negative cases, sTIL high cases showed significantly better DFS independent of PD-L1-IC status. sTIL low PD-L1-IC positive cases also demonstrated a better DFS in HER2–OE cancers. In high–grade luminal B cancers, sTIL high PD-L1-IC positive cases showed the best BCSS.ConclusionThe data suggested that the combining analysis of sTIL and PD-L1-IC expression refined the prognostication of breast cancer subtypes. Cases with high TIL and PD-LI-IC expression appear to be more immune active.     

Acitretin in erosive penile lichen planus

Lichen planus (LP) is an incompletely understood T‐cell mediated auto‐immune dermatosis. When LP involves the genitalia it may present as painful, pruritic erosions that can be exquisitely tender, causing distress and genitourinary and sexual dysfunction. Management of erosive genital LP is often suboptimal. Despite higher order evidence demonstrating the efficacy of oral acitretin in the management of cutaneous and oral LP, it still features below other immunosuppressive and immunomodulatory therapies in many clinicians’ therapeutic ladder. We present a case of severe erosive penile LP, successfully treated with oral acitretin after topical and oral corticosteroids failed to induce remission.