Total haemoglobin mass, but not haemoglobin concentration, is associated with preoperative cardiopulmonary exercise testing-derived oxygen-consumption variables

Background

Cardiopulmonary exercise testing (CPET) measures peak exertional oxygen consumption ( V˙O2peak ) and that at the anaerobic threshold ( V˙O2 at AT, i.e. the point at which anaerobic metabolism contributes substantially to overall metabolism). Lower values are associated with excess postoperative morbidity and mortality. A reduced haemoglobin concentration ([Hb]) results from a reduction in total haemoglobin mass (tHb-mass) or an increase in plasma volume. Thus, tHb-mass might be a more useful measure of oxygen-carrying capacity and might correlate better with CPET-derived fitness measures in preoperative patients than does circulating [Hb].

Methods

Before major elective surgery, CPET was performed, and both tHb-mass (optimized carbon monoxide rebreathing method) and circulating [Hb] were determined.

Results

In 42 patients (83% male), [Hb] was unrelated to V˙O2 at AT and V˙O2peak ( r =0.02, P =0.89 and r =0.04, P =0.80, respectively) and explained none of the variance in either measure. In contrast, tHb-mass was related to both ( r =0.661, P <0.0001 and r =0.483, P =0.001 for V˙O2 at AT and V˙O2peak , respectively). The tHb-mass explained 44% of variance in V˙O2 at AT ( P <0.0001) and 23% in V˙O2peak ( P =0.001).

Conclusions

In contrast to [Hb], tHb-mass is an important determinant of physical fitness before major elective surgery. Further studies should determine whether low tHb-mass is predictive of poor outcome and whether targeted increases in tHb-mass might thus improve outcome.

The effect of neoadjuvant chemotherapy and chemoradiotherapy on exercise capacity and outcome following upper gastrointestinal cancer surgery: an observational cohort study

Background

In 2014 approximately 21,200 patients were diagnosed with oesophageal and gastric cancer in England and Wales, of whom 37 % underwent planned curative treatments. Potentially curative surgical resection is associated with significant morbidity and mortality. For operable locally advanced disease, neoadjuvant chemotherapy (NAC) improves survival over surgery alone. However, NAC carries the risk of toxicity and is associated with a decrease in physical fitness, which may in turn influence subsequent clinical outcome. Lower levels of physical fitness are associated with worse outcome following major surgery in general and Upper Gastrointestinal Surgery (UGI) surgery in particular. Cardiopulmonary exercise testing (CPET) provides an objective assessment of physical fitness. The aim of this study is to test the hypothesis that NAC prior to upper gastrointestinal cancer surgery is associated with a decrease in physical fitness and that the magnitude of the change in physical fitness will predict mortality 1 year following surgery.

Methods

This study is a multi-centre, prospective, blinded, observational cohort study of participants with oesophageal and gastric cancer scheduled for neoadjuvant cancer treatment (chemo- and chemoradiotherapy) and surgery. The primary endpoints are physical fitness (oxygen uptake at lactate threshold measured using CPET) and 1-year mortality following surgery; secondary endpoints include post-operative morbidity (Post-Operative Morbidity Survey (POMS)) 5 days after surgery and patient related quality of life (EQ-5D-5 L).

Discussion

The principal benefits of this study, if the underlying hypothesis is correct, will be to facilitate better selection of treatments (e.g. NAC, Surgery) in patients with oesophageal or gastric cancer. It may also be possible to develop new treatments to reduce the effects of neoadjuvant cancer treatment on physical fitness. These results will contribute to the design of a large, multi-centre trial to determine whether an in-hospital exercise-training programme that increases physical fitness leads to improved overall survival.

Trial registration

ClinicalTrials.gov NCT01325883 - 29^th March 2011.

Timing of surgery following neoadjuvant chemoradiotherapy in locally advanced rectal cancer - A comparison of magnetic resonance imaging at two time points and histopathological responses

PURPOSE

There is wide inter-institutional variation in the interval between neoadjuvant chemoradiotherapy (NACRT) and surgery for locally advanced rectal cancer. We aimed to assess the association of magnetic resonance imaging (MRI) at 9 and 14 weeks post-NACRT; T-staging (ymrT) and post-NACRT tumour regression grading (ymrTRG) with histopathological outcomes; histopathological T-stage (ypT) and histopathological tumour regression grading (ypTRG) in order to inform decision-making about timing of surgery.

PATIENTS AND METHODS

We prospectively studied 35 consecutive patients (26 males) with MRI-defined resection margin threatened rectal cancer who had completed standardized NACRT. Patients underwent a MRI at Weeks 9 and 14 post-NACRT, and surgery at Week 15. Two readers independently assessed MRIs for ymrT, ymrTRG and volume change. ymrT and ymrTRG were analysed against histopathological ypT and ypTRG as predictors by logistic regression modelling and receiver operating characteristic (ROC) curve analyses.

RESULTS

Thirty-five patients were recruited. Inter-observer agreement was good for all MR variables (Kappa > 0.61). Considering ypT as an outcome variable, a stronger association of favourable ymrTRG and volume change at Week 14 compared to Week 9 was found (ymrTRG - p = 0.064 vs. p = 0.010; Volume change - p = 0.062 vs. p = 0.007). Similarly, considering ypTRG as an outcome variable, a greater association of favourable ymrTRG and volume change at Week 14 compared to Week 9 was found (ymrTRG - p = 0.005 vs. p = 0.042; Volume change - p = 0.004 vs. 0.055).

CONCLUSION

Following NACRT, greater tumour down-staging and volume reduction was observed at Week 14. Timing of surgery, in relation to NACRT, merits further investigation.

TRIAL REGISTRATION NUMBER

NCT01325909.

Exercise intervention in people with cancer undergoing neoadjuvant cancer treatment and surgery: A systematic review

BACKGROUND

Neoadjuvant cancer treatment decreases physical fitness. Low levels of physical fitness are associated with poor surgical outcome. Exercise training can stimulate skeletal muscle adaptations, such as increased mitochondrial content and improved oxygen uptake capacity that may contribute to improving physical fitness. This systematic review evaluates the evidence in support of exercise training in people with cancer undergoing the "dual hit" of neoadjuvant cancer treatment and surgery.

METHODS

We conducted a systematic database search of Embase Ovid, Ovid Medline without Revisions, SPORTDiscus, Web of Science, Cochrane Central Register of Controlled Trials Library and ClinicalTrials.gov to identify trials addressing the effect of exercise training in people scheduled for neoadjuvant cancer treatment and surgery. Data extraction and analysis were based on a pre-defined plan.

RESULTS

The database search yielded 6489 candidate abstracts. Ninety-four references included the required terms. Four studies were eligible for inclusion (breast cancer, locally advanced rectal cancer). All studies reported that exercise training was safe and feasible and that adherence rates were acceptable (66-96%). In-hospital exercise training improves physical fitness however the impact on HRQoL and other clinical important outcomes was uncertain.

CONCLUSION

This is the first systematic review of the effects of exercise training in people scheduled for "dual-hit" treatment. This evidence synthesis indicates that this approach is safe and feasible but that there are insufficient controlled trials in this area to draw reliable conclusions about the efficacy of such an intervention, the optimal characteristics of the intervention, or the impact on clinical or patient reported outcomes.

Exercise intervention in people with cancer undergoing adjuvant cancer treatment following surgery: A systematic review

BACKGROUND

Remaining physically active during and after cancer treatment is known to improve associated adverse effects, improve overall survival and reduce the probability of relapse. This systematic review addresses the question: is an exercise training programme beneficial in people with cancer undergoing adjuvant cancer treatment following surgery.

METHODS

A systematic database search of Embase, Ovid, Medline without Revisions, SPORTDiscus, Web of Science, Cochrane Library and ClinicalTrials.gov for any randomised controlled trials (RCT) or non-RCT addressing the effect of an exercise training programme in those having adjuvant cancer treatment following surgery was conducted.

RESULTS

The database search yielded 6489 candidate abstracts of which 94 references included the required terms. A total of 17 articles were included in this review. Exercise training is safe and feasible in the adjuvant setting and furthermore may improve measures of physical fitness and health related quality of life (HRQoL).

CONCLUSION

This is the first systematic review on exercise training interventions in people with cancer undergoing adjuvant cancer treatment following surgery. Due to the lack of adequately powered RCTs in this area, it remains unclear whether exercise training in this context improves clinical outcomes other physical fitness and HRQoL. It remains unclear what is the optimal timing of initiation of an exercise programme and what are the best combinations of elements within an exercise training programme to optimise training efficacy. Furthermore, it is unclear if initiating such exercise programmes at cancer diagnosis may have a long-lasting effect on physically activity throughout the subsequent life course.

The Effect of beta-blockade on objectively measured physical fitness in patients with abdominal aortic aneurysms--A blinded interventional study

BACKGROUND

Perioperative beta-blockade is widely used, especially before vascular surgery; however, its impact on exercise performance assessed using cardiopulmonary exercise testing (CPET) in this group is unknown. We hypothesized that beta-blocker therapy would significantly improve CPET-derived physical fitness in this group.

METHODS

We recruited patients with abdominal aortic aneurysms (AAA) of <5.5 cm under surveillance. All patients underwent CPET on and off beta-blockers. Patients routinely prescribed beta-blockers underwent a first CPET on medication. Beta-blockers were stopped for one week before a second CPET. Patients not routinely taking beta-blockers underwent the first CPET off treatment, then performed a second CPET after commencement of bisoprolol for at least 48 h. Oxygen uptake (.VO2) at estimated lactate threshold and .VO2 at peak were primary outcome variables. A linear mixed-effects model was fitted to investigate any difference in adjusted CPET variables on and off beta-blockers.

RESULTS

Forty-eight patients completed the study. No difference was observed in .VO2 at estimated lactate threshold and .VO2 at peak; however, a significant decrease in .VE/.VCO2 at estimated lactate threshold and peak, an increase in workload at estimated lactate threshold., O2 pulse and heart rate both at estimated lactate threshold and peak was found with beta-blockers. Patients taking beta-blockers routinely (chronic group) had worse exercise performance (lower .VO2 ).

CONCLUSIONS

Beta blockade has a significant impact on CPET-derived exercise performance, albeit without changing .VO2 at estimated lactate threshold and.VO2 at peak. This supports performance of preoperative CPET on or off beta-blockers depending on local perioperative practice.

CLINICAL TRIAL REGISTRATION

NCT 02106286.

Effect of prehabilitation on objectively measured physical fitness after neoadjuvant treatment in preoperative rectal cancer patients: a blinded interventional pilot study

BACKGROUND

Patients requiring surgery for locally advanced rectal cancer often additionally undergo neoadjuvant chemoradiotherapy (NACRT), of which the effects on physical fitness are unknown. The aim of this feasibility and pilot study was to investigate the effects of NACRT and a 6 week structured responsive exercise training programme (SRETP) on oxygen uptake [Formula: see text] at lactate threshold ([Formula: see text]) in such patients.

METHODS

We prospectively studied 39 consecutive subjects (27 males) with T3-4/N+ resection margin threatened rectal cancer who completed standardized NACRT. Subjects underwent cardiopulmonary exercise testing at baseline (pre-NACRT), at week 0 (post-NACRT), and week 6 (post-SRETP). Twenty-two subjects undertook a 6 week SRETP on a training bike (three sessions per week) between week 0 and week 6 (exercise group). These were compared with 17 contemporaneous non-randomized subjects (control group). Changes in [Formula: see text] at [Formula: see text] over time and between the groups were compared using a compound symmetry covariance linear mixed model.

RESULTS

Of 39 recruited subjects, 22 out of 22 (exercise) and 13 out of 17 (control) completed the study. There were differences between the exercise and control groups at baseline [age, ASA score physical status, World Health Organisation performance status, and Colorectal Physiologic and Operative Severity Score for the Enumeration of Mortality and Morbidity (CR-POSSUM) predicted mortality]. In all subjects, [Formula: see text] at [Formula: see text] significantly reduced between baseline and week 0 [-1.9 ml kg(-1) min(-1); 95% confidence interval (CI) -1.3, -2.6; P<0.0001]. In the exercise group, [Formula: see text] at [Formula: see text] significantly improved between week 0 and week 6 (+2.1 ml kg(-1) min(-1); 95% CI +1.3, +2.9; P<0.0001), whereas the control group values were unchanged (-0.7 ml kg(-1) min(-1); 95% CI -1.66, +0.37; P=0.204).

CONCLUSIONS

NACRT before rectal cancer surgery reduces physical fitness. A structured exercise intervention is feasible post-NACRT and returns fitness to baseline levels within 6 weeks.

CLINICAL TRIAL REGISTRATION NCT

01325909.

Effect of prehabilitation on objectively measured physical fitness after neoadjuvant treatment in preoperative rectal cancer patients: a blinded interventional pilot study

BACKGROUND

Patients requiring surgery for locally advanced rectal cancer often additionally undergo neoadjuvant chemoradiotherapy (NACRT), of which the effects on physical fitness are unknown. The aim of this feasibility and pilot study was to investigate the effects of NACRT and a 6 week structured responsive exercise training programme (SRETP) on oxygen uptake [Formula: see text] at lactate threshold ([Formula: see text]) in such patients.

METHODS

We prospectively studied 39 consecutive subjects (27 males) with T3-4/N+ resection margin threatened rectal cancer who completed standardized NACRT. Subjects underwent cardiopulmonary exercise testing at baseline (pre-NACRT), at week 0 (post-NACRT), and week 6 (post-SRETP). Twenty-two subjects undertook a 6 week SRETP on a training bike (three sessions per week) between week 0 and week 6 (exercise group). These were compared with 17 contemporaneous non-randomized subjects (control group). Changes in [Formula: see text] at [Formula: see text] over time and between the groups were compared using a compound symmetry covariance linear mixed model.

RESULTS

Of 39 recruited subjects, 22 out of 22 (exercise) and 13 out of 17 (control) completed the study. There were differences between the exercise and control groups at baseline [age, ASA score physical status, World Health Organisation performance status, and Colorectal Physiologic and Operative Severity Score for the Enumeration of Mortality and Morbidity (CR-POSSUM) predicted mortality]. In all subjects, [Formula: see text] at [Formula: see text] significantly reduced between baseline and week 0 [-1.9 ml kg(-1) min(-1); 95% confidence interval (CI) -1.3, -2.6; P<0.0001]. In the exercise group, [Formula: see text] at [Formula: see text] significantly improved between week 0 and week 6 (+2.1 ml kg(-1) min(-1); 95% CI +1.3, +2.9; P<0.0001), whereas the control group values were unchanged (-0.7 ml kg(-1) min(-1); 95% CI -1.66, +0.37; P=0.204).

CONCLUSIONS

NACRT before rectal cancer surgery reduces physical fitness. A structured exercise intervention is feasible post-NACRT and returns fitness to baseline levels within 6 weeks.

CLINICAL TRIAL REGISTRATION NCT

01325909.

The effects of neoadjuvant chemoradiotherapy on physical fitness and morbidity in rectal cancer surgery patients

BACKGROUND

Neoadjuvant chemoradiotherapy (NACRT) followed by surgery for resectable locally advanced rectal cancer improves outcome compared with surgery alone. Our primary hypothesis was that NACRT impairs objectively-measured physical fitness. We also wished to explore the relationship between fitness and postoperative outcome.

METHOD

In an observational study, we prospectively studied 27 consecutive patients, of whom 25 undertook cardiopulmonary exercise testing (CPET) 2 weeks before and 7 weeks after standardized NACRT, then underwent surgery. In-hospital post-operative morbidity and mortality were recorded. Patients were followed up to 1 year for mortality. Data was analysed blind to clinical details. Receiver-operating characteristic (ROC) analysis defined the predictive value of CPET for in-hospital morbidity at day 5.

RESULTS

Oxygen uptake ( [Formula: see text] in ml kg(-1) min(-1)) at estimated lactate threshold (θˆL) and at peak exercise ( [Formula: see text] at peak in ml kg(-1) min(-1)) both significantly decreased post-NACRT: [Formula: see text] at θˆL 12.1 (pre-NACRT) vs. 10.6 (post-NACRT), p < 0.001 (95%CI -1.7, -1.2); [Formula: see text] at peak 18.1 vs. 16.7, p < 0.001 (95%CI -3.1, -1.0). Optimal [Formula: see text] at θˆL and peak pre-NACRT for predicting postoperative morbidity were 12.0 and 18.1 ( [Formula: see text] at θˆL - AUC = 0.71, 77% sensitive and 75% specific; [Formula: see text] at peak - AUC = 0.75, 78% sensitive and 76% specific). Optimal [Formula: see text] at θˆL and peak post-NACRT for predicting postoperative morbidity were 10.7 and 16.7 ( [Formula: see text] at θˆL - AUC = 0.72, 77% sensitive and 83% specific; [Formula: see text] at peak - AUC = 0.80, 85% sensitive and 83% specific).

CONCLUSION

NACRT before major rectal cancer surgery significantly decreased physical fitness as assessed by CPET.

TRIALS REGISTRY NUMBER

NCT01334593.