Functional outcomes following pelvic exenteration: results from a prospective cohort study.

AIM: Postoperative functional outcomes following pelvic exenteration surgery for treatment of advanced or recurrent pelvic malignancies are poorly understood. The aim of this study was to determine the short-term functional outcomes following pelvic exenteration surgery using objective measures of physical function. METHOD: Patients undergoing pelvic exenteration surgery between January 2017 and May 2020 were recruited at a single quaternary referral hospital in Sydney, Australia. The primary measures were the 6-min walk test (6MWT) and the five times sit to stand (5STS) test. Data were collected at baseline (preoperatively), 10 days postoperatively and at discharge from hospital, and were analysed according to tumour type, extent of exenteration, sacrectomy, length of hospital stay, major nerve resection and postoperative complications. RESULTS: The cohort of patients that participated in functional assessments consisted of 135 patients, with a median age of 61 years. Pelvic exenteration patients had a reduced 6MWT distance preoperatively compared to the general population (P < 0.001). Following surgery, we observed a further decrease in 6MWT distance (P < 0.001) and an increase in time to complete 5STS (P < 0.001) at postoperative day 10 compared to baseline, with a slight improvement at discharge. There were no differences in 6MWT and 5STS outcomes between patients based on comparisons of surgical and oncological factors. CONCLUSION: Pelvic exenteration patients are functionally impaired in the preoperative period compared to the general population. Surgery causes a further reduction in physical function in the short term; however, functional outcomes are not impacted by tumour type, extent of exenteration, sacrectomy or nerve resection.

Random and combinatorial mutagenesis for improved total production of secretory target protein in Escherichia coli.

Signal peptides and secretory carrier proteins are commonly used to secrete heterologous recombinant protein in Gram-negative bacteria. The Escherichia coli osmotically-inducible protein Y (OsmY) is a carrier protein that secretes a target protein extracellularly, and we have previously applied it in the Bacterial Extracellular Protein Secretion System (BENNY) to accelerate directed evolution. In this study, we reported the first application of random and combinatorial mutagenesis on a carrier protein to enhance total secretory target protein production. After one round of random mutagenesis followed by combining the mutations found, OsmY(M3) (L6P, V43A, S154R, V191E) was identified as the best carrier protein. OsmY(M3) produced 3.1 ± 0.3 fold and 2.9 ± 0.8 fold more secretory Tfu0937 ß-glucosidase than its wildtype counterpart in E. coli strains BL21(DE3) and C41(DE3), respectively. OsmY(M3) also produced more secretory Tfu0937 at different cultivation temperatures (37 °C, 30 °C and 25 °C) compared to the wildtype. Subcellular fractionation of the expressed protein confirmed the essential role of OsmY in protein secretion. Up to 80.8 ± 12.2% of total soluble protein was secreted after 15 h of cultivation. When fused to a red fluorescent protein or a lipase from Bacillus subtillis, OsmY(M3) also produced more secretory protein compared to the wildtype. In this study, OsmY(M3) variant improved the extracellular production of three proteins originating from diverse organisms and with diverse properties, clearly demonstrating its wide-ranging applications. The use of random and combinatorial mutagenesis on the carrier protein demonstrated in this work can also be further extended to evolve other signal peptides or carrier proteins for secretory protein production in E. coli.

Feasibility and acceptability of a preoperative exercise program for patients undergoing major cancer surgery: results from a pilot randomized controlled trial.

OBJECTIVE: To establish the feasibility and acceptability of a preoperative exercise program, and to obtain pilot data on the likely difference in key surgical outcomes to inform the sample size calculation for a full-scale trial. DESIGN: Pilot randomized controlled trial. SETTING: Royal Prince Alfred Hospital, Sydney, Australia. SUBJECTS: We included patients undergoing elective pelvic exenteration or cytoreductive surgery aged 18 to 80 years, who presented to the participating gastrointestinal surgeon at least 2 weeks prior to surgery. Patients presenting cognitive impairment, co-morbidity preventing participation in exercise, inadequate English language, currently participating in an exercise program or unable to attend the exercise program sessions were excluded. METHODS: Participants were randomized to a 2-6 weeks preoperative, face-to-face, individualised exercise program or to usual care. Feasibility was assessed with consent rates to the study, and for the intervention group, retention and adherence rates to the preoperative exercise program. Acceptability of the exercise program was assessed with a semi-structured questionnaire exploring the advice received and the amount, duration and intensity of the exercise program. In addition, postoperative complication rates (Clavien-Dindo), length of hospital stay and self-reported measures of health-related quality of life (SF-36v2) were collected at baseline, day before surgery and in-hospital up to discharge from hospital. RESULTS: Of 122 patients screened, 26 (21%) were eligible and 22 (85%) accepted to participate in the trial and were randomized to the intervention (11; 50%) or control group (11; 50%). The median age of the include participants was 63 years. Adherence to the preoperative exercise sessions was 92.7%, with all participants either satisfied (33%) or extremely satisfied (67%) with the overall design of the preoperative exercise program. No significant differences in outcomes were found between groups. CONCLUSIONS: The results of our pilot trial demonstrate that a preoperative exercise program is feasible and acceptable to patients undergoing major abdominal cancer surgery. There is an urgent need for a definite trial investigating the effectiveness of a preoperative exercise program on postoperative outcomes in patients undergoing major abdominal cancer surgery. This could potentially reduce postoperative complication rates, length of hospital stay and subsequently overall health care costs. TRIAL REGISTRATION: ACTRN12617001129370. Registered on August 1, 2017, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373396&showOriginal=true&isReview=true.

Feasibility and acceptability of PrE-operative Physical Activity to improve patient outcomes After major cancer surgery: study protocol for a pilot randomised controlled trial (PEPA Trial).

BACKGROUND: There is a need for evidence of the effectiveness of pre-operative exercise for patients undergoing major cancer surgery; however, recruitment to such trials can be challenging. The PrE-operative Physical Activity (PEPA) Trial will establish the feasibility and acceptability of a pre-operative exercise programme aimed to improve patient outcomes after cytoreductive surgery and pelvic exenteration. The secondary aim is to obtain pilot data on the likely difference in key outcomes (post-operative complications, length of hospital stay, post-operative functional capacity and quality of life) to inform the sample size calculation for the substantive randomised clinical trial. METHODS/DESIGN: Twenty patients undergoing cytoreductive surgery and pelvic exenteration at the Royal Prince Alfred Hospital, Sydney will be recruited and randomly allocated (1:1 ratio) to either 2 to 6 weeks' pre-operative exercise programme (intervention group) or usual care (control group). Those randomised to the intervention group will receive up to six individualised, 1-h physiotherapy sessions (including aerobic and endurance exercises, respiratory muscle exercises, stretching and flexibility exercises), home exercises (instruction and recommendations on how to progress the exercises at home) and encouragement to be more active by using an activity tracker to measure the number of steps walked daily. Patients allocated to the control group will not receive any specific advice about exercise training. Feasibility will be assessed with consent rates to the study, and for the intervention group, retention and adherence rates to the exercise programme. Acceptability of the exercise programme will be assessed with a semi-structured questionnaire. The following measures of the effectiveness of the intervention will be collected at baseline (2 to 6 weeks pre-operative), a week before surgery, during hospital stay and pre hospital discharge: post-operative complication rates (Clavien-Dindo), post-operative functional capacity (Six-minute Walk Test) and quality of life (SF-36v2®) and length of hospital stay. Functional status will be additionally measured using Cardiopulmonary Exercise Testing (CPET), at baseline and within a week before surgery. DISCUSSION: The PEPA Trial will provide important information about the feasibility and acceptability of a pre-operative exercise programme for patients undergoing major cancer surgery. Data from the PEPA Trial will be used to inform the design, methodology and to calculate sample size required for a larger, definitive trial. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ID: ACTRN12617001129370 . Registered on 1 August 2017.