Use of negative pressure wound therapy on locoregional flaps: a case-control study.

OBJECTIVE: The use of negative pressure wound therapy (NPWT) is ubiquitous in the management of complex wounds. Extending beyond the traditional utility of NPWT, it has been used after reconstructive flap surgery in a few case series. The authors sought to investigate the outcomes of NPWT use on flap reconstruction in a case-control study. METHOD: Patients who underwent flap reconstruction between November 2017 and January 2020 were reviewed for inclusion in the study, and divided into an NPWT group and a control group. For patients in the NPWT group, NPWT was used directly over the locoregional flap immediately post-surgery for 4-7 days, before switching to conventional dressings. The control group used conventional dressing materials immediately post-surgery. Outcome measures such as flap necrosis, surgical site infections (SSIs), wound dehiscence as well as time to full functional recovery and hospitalisation duration were evaluated. RESULTS: Of the 138 patients who underwent flap reconstruction, 37 who had free flap reconstructions were excluded, and 101 patients were included and divided into two groups: 51 patients in the NPWT group and 50 patients in the control group. Both groups had similar patient demographics, and patient and wound risk factors for impaired wound healing. Results showed that there was no statistically significant difference between flap necrosis, SSIs, wound dehiscence, hospitalisation duration as well as functional recovery rates. Cost analysis showed that the use of NPWT over flaps for the first seven postoperative days may potentially be more cost effective in our setting. CONCLUSION: In this study, the appropriate use of NPWT over flaps was safe and efficacious in the immediate postoperative setting, and was not inferior to the conventional dressings used for reconstructive flap surgery. The main benefits of NPWT over flaps include better exudate management, oedema reduction and potential cost savings. Further studies would be required to ascertain any further benefit.

Structured Training for Laparoscopic Appendectomy for Residents (STAR Trial)-A Randomized Pilot Study.

OBJECTIVE: Laparoscopic appendectomy is a common operation that is frequently performed by junior surgical residents. We investigated the effect of a structured training program on the proficiency of junior residents in acquiring skills necessary in this operation. DESIGN AND PARTICIPANTS: This is a randomized pilot trial. Between December 2014 and July 2018, twenty junior residents were recruited for this study. 11 were randomized to receive a structured training program of supervised, task-specific training. Each resident subsequently performed ten cases of laparoscopic appendectomy with their performance assessed for the last 5. The GOALS scale was used as the primary endpoint. Secondary endpoints were perioperative outcomes. The effect of intervention on these outcomes were evaluated assuming a linear mixed effect multi-level model. The study was single-blinded as the assessors did not know which group each resident belonged to. RESULTS: There were no statistically significant differences in the total GOALS score or any of its individual domains. After adjusting for the number of operations done within the trial, the mean difference between the total GOALS score was 0.07 (95% CI -0.76 to 0.90, P=0.866). Blood loss, hospital stay and postoperative complication rates were similar. There was suggestion of a shorter operative time (effect estimate -9.03, 95% CI -19.56 to 1.50) in the intervention arm although statistical significance was not achieved. No avoidable adverse events due to this study were recorded. CONCLUSION: Structured training program did not significantly improve surgical performance and outcomes in laparoscopic appendectomy in this pilot trial. Despite these findings, residents can still potentially mount their learning curves in laparoscopy earlier in a safe environment with such a program which is especially important in the era of minimally invasive surgery.

FAM46C/TENT5C functions as a tumor suppressor through inhibition of Plk4 activity.

Polo like kinase 4 (Plk4) is a tightly regulated serine threonine kinase that governs centriole duplication. Increased Plk4 expression, which is a feature of many common human cancers, causes centriole overduplication, mitotic irregularities, and chromosomal instability. Plk4 can also promote cancer invasion and metastasis through regulation of the actin cytoskeleton. Herein we demonstrate physical interaction of Plk4 with FAM46C/TENT5C, a conserved protein of unknown function until recently. FAM46C localizes to centrioles, inhibits Plk4 kinase activity, and suppresses Plk4-induced centriole duplication. Interference with Plk4 function by FAM46C was independent of the latter's nucleotidyl transferase activity. In addition, FAM46C restrained cancer cell invasion and suppressed MDA MB-435 cancer growth in a xenograft model, opposing the effect of Plk4. We demonstrate loss of FAM46C in patient-derived colorectal cancer tumor tissue that becomes more profound with advanced clinical stage. These results implicate FAM46C as a tumor suppressor that acts by inhibiting Plk4 activity.

Plk4 Promotes Cancer Invasion and Metastasis through Arp2/3 Complex Regulation of the Actin Cytoskeleton.

The polo family serine threonine kinase Plk4 has been proposed as a therapeutic target in advanced cancers based on increased expression in primary human cancers, facilitation of tumor growth in murine xenograft models, and centrosomal amplification induced by its overexpression. However, both the causal link between these phenomena and the feasibility of selective Plk4 inhibition remain unclear. Here we characterize Plk4-dependent cancer cell migration and invasion as well as local invasion and metastasis of cancer xenografts. Plk4 depletion suppressed cancer invasion and induced an epithelial phenotype in poorly differentiated breast cancer cells. In an unbiased BioID screen for Plk4 interactors, we identified members of the Arp2/3 complex and confirmed a physical and functional interaction between Plk4 and Arp2 in mediating Plk4-driven cancer cell movement. This interaction is mediated through the Plk4 Polo-box 1-Polo-box 2 domain and results in phosphorylation of Arp2 at the T237/T238 activation site, which is required for Plk4-driven cell movement. Our results validate Plk4 as a therapeutic target in cancer patients and reveal a new role for Plk4 in regulating Arp2/3-mediated actin cytoskeletal rearrangement. Cancer Res; 77(2); 434-47. ©2016 AACR.

Bacteriological study in perianal abscess is not useful and not cost-effective.

BACKGROUND: The detection of gut organisms in perianal abscesses has been postulated to suggest an underlying communication with the anal canal. However, recent studies appear to contradict this observation. The aim of this study is to determine the value of bacteriological studies in perianal abscesses. METHODS: A retrospective study of all patients who have had a surgical drainage of their perianal abscesses with concomitant microbiological examination from January 2010 to December 2012 was performed. Patients with known underlying anal fistula, Crohn's disease or previous perianal operations were excluded. RESULTS: A total of 164 patients, median age of 42.0 years (range 8-87) comprising of 78.7% males formed the study group. Gut organisms were cultured in 143 (87.2%) samples while 12 (7.3%) demonstrated skin organisms and nine did not yield any bacterial growth (5.5%). Twenty-nine (17.7%) patients developed anal fistula and 34 (20.7%) patients had a recurrence of the perianal abscess. The median follow-up period was 1450 (14-2391) days. There was no significant association between the presence of gut organism and development of fistulas (odds ratio = 0.48; 95% confidence interval = 0.17-1.37) or recurrence of perianal abscess (odds ratio = 1.66; 95% confidence interval = 0.46-6.01). CONCLUSION: Bacteriological culture in perianal abscess is not useful for predicting the development of anal fistula or abscess recurrence. Hence, there is no need to perform this investigation on a routine basis.