Kristin Campbell

The current five-year survival rate for colorectal cancer in Canada is 65%, which is influenced by well-established factors (e.g., age, cancer stage). There is also consistent observational research that higher body mass or social factors (e.g., living alone) can negatively impact survival. This thesis project examined the association between body composition at diagnosis and relapse-free survival (RFS) at three years post-diagnosis, and how these relationships may be influenced by social or psychological factors at diagnosis in individuals with colon cancer. Methods: A cohort of individuals treated for stage III colon cancer at BC Cancer from 2012 to 2015 with clinical and demographic data available was created. CT scans of the third lumbar vertebra at diagnosis were analyzed to determine skeletal muscle index (SMI) (muscle cross-sectional area normalized for height), sarcopenia (using published SMI cut-off points), skeletal muscle density (SMD) (average attenuation of muscle), and skeletal muscle gauge (SMG) (SMI multiplied by SMD). Social and psychological factors were obtained at diagnosis and included social isolation, patient-reported concerns, and symptoms of anxiety and depression from BC Cancer’s Psychosocial Screen for Cancer-Revised, and community size and neighbourhood income based on individuals’ postal codes. Multivariable logistic regression models were used to examine: 1) The associations of SMI, SMD, SMG, and sarcopenia with RFS; 2) How social and psychological factors (selected using variable visualization and univariable regression) influenced the relationships. Results: Individuals were a median age of 62.0 years and 51.1% were male. Individuals with a lower SMD (OR= 0.97, 95% CI= 0.95,0.997), lower SMG (for a 100-unit change, OR= 0.93, 95% CI= 0.88,0.98), or sarcopenia (OR= 1.80, 95% CI= 1.06,3.10) had greater odds of having a relapse. This association was influenced by social isolation; for any given SMD, SMG, or sarcopenia status, individuals with one or more markers of social isolation had approximately two times greater odds of having a relapse than individuals without markers of social isolation. Conclusion: Consistent with the literature, sarcopenia was associated with RFS, as was SMD and SMG, measures for which there is less evidence surrounding their relationship with long-term outcomes. Social isolation appeared to influence these relationships.

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As many breast cancer survivors (BCS) in British Columbia report difficulties accessing physiotherapy (PT), which increases their risk of developing chronic shoulder and arm issues, strategies are needed to inform effective PT program design. This thesis project used sequential mixed methods to develop a pilot discrete choice experiment (DCE) to understand the feasibility of using DCE methodology to elicit BCSs’ preferences for PT services. Methods: First, focus groups were held with BCS (n=35) to identify key attributes and levels of PT care: timing of education, method of PT referral, timing of first PT appointment, physiotherapist expertise level, treatment frequency, treatment format, and out-of-pocket cost. Second, think aloud interviews were conducted with BCS (n=5) to explore attribute and level relevance and task comprehension. Third, an experimental design of 32 choice tasks (separated into two blocks) was created from the identified attributes and levels, quantitatively pilot tested with BCS, and fit using an error-component mixed logit model to estimate preference data. Feasibility was assessed based on: (i) response rate; (ii) completion rate; and (iii) respondent diversity. Results: The pilot DCE had a 21% response rate and 17% of respondents completed the entire questionnaire and provided usable data. All respondents identified as female and were mean of 9.1 years post-diagnosis. Most received PT treatment for breast cancer-related issues (69%), completed post-secondary education (77%), and had annual family incomes of at least $80,000 (69%). Preliminary preference data indicate, on average, respondents preferred breast surgeon referral to PT, less time between surgery completion and receipt of first PT appointment, a physiotherapist with greater breast cancer-specific expertise, and to pay less out-of-pocket for PT treatment. Conclusion: Given the low response and completion rates and respondent homogeneity, alternative recruitment strategies and choice task instruction and presentation should be explored before beginning a full-scale DCE. As this DCE was a pilot study, preference data should be interpreted with caution and not inferred to reflect the preferences of the wider population of BCS. Preference data from the full-scale DCE may be incorporated into exploratory policy analyses and programming for breast cancer-specific PT services in British Columbia.

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Exercise has been shown to be an effective strategy to enhance survivorship and improve quality of life in individuals with prostate cancer. However, the majority of men with prostate cancer do not meet the exercise guidelines for cancer survivors that recommend achieving a minimum of 150-minutes of moderate-to-vigorous aerobic exercise and two resistance exercise sessions weekly. To assist in the adoption and maintenance of exercise behaviours, the Prostate Cancer Supportive Care (PCSC) program implemented an exercise clinic that included group education and individualized exercise counselling delivered by an exercise physiologist. The primary aim of this dissertation was to evaluate the feasibility of the delivery of the exercise clinic and to understand the preliminary effect of this clinic at changing exercise behaviours over a 3-month period. A retrospective chart review was performed on data collected from attendees of the PCSC Program Exercise Clinic version 2.0 protocol from June 11 2018 to April 10 2019 from four appointment sessions: Education session, exercise clinic session 1 (first in-person exercise clinic session), exercise clinic session 2 (telephone follow-up session) and exercise clinic session 3 (3-month in-person follow-up session). Feasibility was defined a priori and measured by attendance, attrition, session timing, intervention delivery fidelity and intervention component fidelity. Self-reported aerobic and resistance exercise levels were evaluated at each session. The results show that this study exceeded feasibility targets for attendance, attrition, intervention fidelity and in-person session timing. There was intervention component fidelity in 38 of 39 components. Aerobic exercise levels at 3-months had increased by 83198 minutes per week of moderate-to-vigorous aerobic exercise with a moderate effect (ES 0.54, 95% CI 0.3-0.5) and resistance exercise increased by 2.03.1 sessions per week with a large effect (ES 0.77, 95% CI 0.3-1.3). Overall, this intervention was feasible to deliver to individuals with prostate cancer in a real-world clinical setting by exercise physiologists. The exercise counselling intervention elicited a moderate effect, showing improvements in aerobic and resistance exercise levels across 3-months. Future work should explore if this behaviour change can be sustained longer-term.

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Computed tomography (CT) imaging presents an accurate and readily available method to quantify changes in body composition within colon cancer patients. Unwanted changes in body composition is one pathway in which cancer outcomes, particularly survival, may be altered in this population. Sarcopenic cancer patients consistently exhibit poorer overall survival compared to non-sacropenic cancer patients. Physical activity is associated with favourable changes in body composition, namely through promoting reductions in visceral adipose tissue and increases in muscle mass. The purpose of this feasibility study is to evaluate the practicality of using CT scans to quantify changes in body composition over time between colon cancer patients who had completed primary cancer treatment randomized to a physical activity intervention (intervention group) or usual care (control group). Eighteen participants who had completed a minimum of 12 months of the CO.21 Trial from the Vancouver CO.21 Trial center were included. Body composition outcomes were measured at baseline, 6 months and 12 months using CT scans taken as part of routine practice. Manual image analysis time took on average longer (17min:20sec) then automated analysis (57sec). Image retention rate was high (97.9%), and only a small proportion of images were deemed as having major quality issues (5.9%). All but one quantified body composition outcome had excellent measured inter- and intra-rater reliability (ICC >0.9). There were no significant time and group effect (p
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Background: Cancer survivors report unique health complications associated with their treatment. Common symptoms include pain, compromised physical functioning, and lymphedema. Although these complications are highly responsive to physical therapy, many cancer survivors do not receive adequate physical therapy care. Furthermore, the delivery of physical therapy services for cancer survivors in British Columbia (BC) has not yet been investigated, warranting an inquiry specific to BC.Purpose: To develop an accurate description of the physical therapy services and programs currently accessible to oncology patients within BC’s public health care system.Methods: A standardized survey was used to investigate the provision of physical therapy to cancer survivors across BC. Public health care sites offering physical therapy services were identified through a comprehensive list of BC hospitals and out-patient health centres. Public practice health care professionals responsible for overseeing physical therapy at each site were requested to complete a survey regarding the physical therapy care provided to cancer survivors at their respective location. Results: Of the 98 sites contacted, surveys were collected for 92 for an overall response rate of 94%. Seventy-one (77%) of sites offered physical therapy to oncology patients, and two (2%) reported having an oncology-specific rehabilitation program, both of which were exclusive to breast cancer survivors and located in the lower mainland (Vancouver and Surrey). Thirty-one (44% of) participants agreed that the services currently being offered at their site were meeting the needs of their patients, 15 (21%) did not consider current services to be adequately meeting the needs of their oncology population, and 25 (35%) were unsure. The most common reasons for not meeting patient needs was lack of funding (83%), lack of professionals experienced in oncology rehabilitation (73%), and lack of resources (e.g., equipment) (70%).Conclusion: In BC, only two public health care sites deliver oncology-specific rehabilitation programs. The remaining sites offer services to oncology patients based on need. A minority of sites report meeting patient rehabilitation needs, with primary barriers being lack of funding, resources, and specialized health care professionals.

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Taxane-based chemotherapy is frequently administered to treat breast cancer. However, side effects of taxanes include chemotherapy-induced peripheral neuropathy (CIPN) and cardiovascular complications, which negatively impact patient quality of life and long-term health. Exercise can significantly reduce cancer treatment side effects. However, information on exercise’s influence on taxane-specific side effects is limited. The primary aim of this dissertation was to evaluate the effect of exercise on taxane side effects, including CIPN and cardiovascular outcomes, in women with breast cancer. METHODS: Women with early-stage breast cancer were randomized to thrice-weekly exercise (EX) or usual care (UC) during taxane chemotherapy (4 cycles, 2-3 weeks apart). Patient-reported CIPN symptoms and quality of life (EORTC QLQ-C30 + CIPN20 subscale), clinical CIPN tests (vibration sensation and pinprick), patient-reported pain (Brief Pain Inventory) and cardiovascular outcomes, including heart rate and blood pressure at rest, and during and after submaximal exercise testing, were evaluated at baseline (pre-taxane chemotherapy) and end of chemotherapy. CIPN symptoms and quality of life were also evaluated at 0-3 days pre-chemotherapy cycle 4. RESULTS: Twenty-four women enrolled (EX: n=11, UC: n=13). Patient-reported CIPN symptoms were significantly worse by the end of chemotherapy in both groups for sensory (p
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Background: Following chemotherapy, it is estimated that up to 95% of all cancer patients report cognitive changes such as complaints with memory and difficulty concentrating. This condition is referred to as chemotherapy-associated cognitive dysfunction or “chemo brain”. In addition, deficits in physical function are observed among those undergoing cancer treatment, as well as, long-term cancer survivors. While a decrease in physical activity participation has been shown among colorectal cancer patients over the course of chemotherapy, to date, changes in functional mobility over the course of chemotherapy has not been assessed in colon cancer patients using objective validated mobility tests. Furthermore, the association of cognitive and functional mobility dysfunction has not been explored. Purpose: To examine the effect of chemotherapy treatment on cognitive function, functional mobility and physical activity from baseline, to 6 months (end of chemotherapy) in individual being treated for colon cancer. Methods: At baseline and end of chemotherapy, participant completed a neuropsychological test battery, which included the Stroop, Hopkins Verbal Learning Test-Revised (HVLT-R), and Trail Making A & B (TMT A&B), a 6-minute walk test (6MWT), a measure of physical function, and a functional mobility testing battery, which included timed up and go (TUG) and gait speed. Demographic information and self-reported physical activity, using the International Physical Activity Questionnaire (IPAQ), were also collected at these time points. For the analysis of neuropsychological and mobility test scores, the paired t-test was used to test for the differences and assess the change in the mean scores from the baseline to 6-months. Results: No significant changes were noted in the HVLT-R, Stroop, and TMT-A and -B mean scores after completion of chemotherapy compared to baseline. Compared to baseline, no significant changes were observed for 6MWT, TUG, GS, or leisure-time physical activity after completion of chemotherapy. Conclusions: There were no significant changes in chemotherapy-associated cognitive, physical function, or functional mobility noted from baseline to the end of chemotherapy. In addition, physical activity levels and average time spent sitting did no change significantly. No definitive statements can be provided since the results are based on a small sample size.

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INTRODUCTION: Physical activity (PA) levels in children who have completed treatment for acute lymphoblastic leukemia (ALL) have been shown to be lower than their healthy peers. Obesity and related health concerns have been recognized as long-term side-effect of cancer treatment. Motor performance and physical function have been shown to be lower in these children compared with children who have not had a cancer diagnosis. Whether or not these two physical factors are related to PA levels in these children is unknown. PURPOSE: To determine if motor performance and physical function are associated with PA in children who have completed treatment for ALL. METHODS: PA was measured using the Physical Activity Questionnaire for Older Children (PAQ-C); motor performance was measured using the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition, Short Form (BOT-2 SF); and physical function was measured using the Six-Minute Walk Test (6MWT). RESULTS: Thirteen participants were recruited. PAQ-C scores were not related to standardized scores from the BOT-2 SF (Spearman’s rho, rs = 0.282, p = 0.35) and 6-minute walk distance (6MWD) (rs = -0.429, p = 0.14) and 6MWD Standard Deviation Score (SDS) (rs = -0.094, p = 0.76). Only 1/13 participants performed below average in the BOT-2 SF, and 11/13 participants walked shorter distances compared with published data from healthy children in the 6MWT (mean 6MWD SDS: -1.62). Body mass index SDS were significantly associated with measured 6MWD (rs = 0.602, p = 0.03) and 6MWD SDS (rs = -0.691 p = 0.01). CONCLUSION: PA was not associated with motor performance or physical function. Physical function was poorer compared with healthy children in 11/13 participants. Healthcare professionals can focus on improving physical function and improving weight management to help reduce risk of obesity and associated health consequences in children who have completed treatment for ALL. Future research should include a larger sample size and include psychosocial factors, such as self-efficacy and parental influence, in exploring factors related to PA childhood ALL survivors.

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Fatigue is one of the most commonly reported side effects during treatment for breast cancer, andfor some individuals can continue for an extended period following treatment completion.Cancer-related fatigue is multi-factorial in nature, and one hypothesized mechanism of bothdevelopment and persistence of cancer-related fatigue following treatment is cardiorespiratoryand muscular deconditioning. The purpose of this study is to compare lactate threshold, VO₂peak and central vs. peripheral causes of muscular fatigue in breast cancer survivors withpersistent cancer-related fatigue (FG) and the control group (CG), breast cancer survivorswithout persistent cancer-related fatigue following treatment for breast cancer. METHODS:During first testing visit, power output at lactate threshold, lactate threshold as a percentageof peak power output, and absolute and relative VO₂ peak were determined using a gradedincremental maximal exercise test on a cycle ergometer. During the second testing visit centraland peripheral muscle fatigue following a sustained contraction of the right quadriceps wereassessed using the twitch interpolation technique and measurement of voluntary activation,control twitch, maximum voluntary contraction and endurance time. RESULTS: There were nosignificant differences in age, body weight, or time since completion of treatment betweengroups. There were no significant differences between groups in power output at lactatethreshold (FG 60.7±17.0 vs. CG 73.3±22.2 W, p=0.14), lactate threshold as a percentage of peakpower output (FG 46.8±8.6 vs. CG 55.0±14.7%, p=0.11), peak power output (FG132.12±38.2vs. CG 140.6±5.9 W, p=0.66), absolute VO2 peak (FG 1.51±0.39 vs. CG 1.74±0.38 L/min,p=0.19), or relative VO2 peak (FG 22.4±4.9 vs. CG 23.6±7.1 ml/kg/min, p=0.62). Results didapproach significance for power output at lactate threshold (p=0.10) and absolute VO₂ peak(p=0.08) when adjusted for age. Central fatigue was responsible for muscular fatigue in theivcontrol group, while muscular fatigue in the cancer-related fatigue group was more due toperipheral mechanisms. CONCLUSION: While no statistically significant differences werefound between groups, results suggest that deconditioning may play a role in cancer-relatedfatigue. Future research into the use of exercise training as a tool to improve deconditioning andthereby reduce this proposed aspect of cancer-related fatigue is warranted.

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