Owner's perception of carboplatin in conjunction with other palliative treatments for cancer therapy

A rapid state-of the-art review of client-reported outcomes measures used to assess dogs' clinical signs and quality of life during chemotherapy

BACKGROUND

Quality of life is an essential component of decision-making in veterinary oncology. Poor management of adverse events during chemotherapy can impair dogs' quality of life and be life-threatening. Consequently, client-reported outcome measures (CROMs) are being proposed to help assess both clinical signs and quality of life. The purpose of this rapid review was to: (1) identify existing CROMs that have been used to assess dogs' clinical signs and quality of life during chemotherapy; and (2) evaluate their methodological development to inform adaptation or development of a CROM for use in routine clinical practice, including remote monitoring. Databases (Scopus, Web of Science, PUBMED/MEDLINE) were searched for CROMs (questionnaires) completed by a non-expert family member about their companion dog. CROM content (domains measured) and scale quality were appraised.

RESULTS

Ten CROMs were identified and three were variations of the same tool. Content of the CROMs varied considerably (range 3-17 domains) with gastrointestinal being the most frequently measured clinical sign cluster (9/10 studies), followed by mobility/ambulatory activity (7/10) and global quality of life (6/10). No CROMs adhered to quality standards for the development of questionnaires and most failed to include qualitative design methods and basic psychometric assessment to ensure reliability and validity (such as internal consistency, test-retest reliability or factor analysis).

CONCLUSION

The validity and reliability of existing chemotherapy CROMs for dogs remains under-tested. Although CROMs combined with remote digital monitoring have the potential to enhance patient care, as has been demonstrated with physician-based oncology, there is a need to apply quality standards to ensure optimal validation. Interdisciplinary collaborations would likely improve CROM quality and clinical utility thereby allowing veterinary healthcare professionals to better support their patients.

Comparison of Three Chemotherapy Protocols With Electrochemotherapy for the Treatment of Feline Cutaneous Squamous Cell Carcinoma

Electrochemotherapy (ECT) with intravenous (IV) and/or intratumoral (IT) bleomycin has shown considerable efficacy in the treatment of non-resectable feline cutaneous squamous cell carcinoma (cSCC), boasting response rates of up to 95%, but other chemotherapy protocols have not yet been investigated. The objective of this prospective multicentre study was to compare the overall response rate (ORR) and progression-free interval (PFI) between cats with cSCC treated with ECT using IT and IV carboplatin (IV + IT), IV carboplatin (IV) or IV bleomycin (IV). A total of 44 cats with unresectable cSCC across three centres were enrolled and treated with ECT using carboplatin IV + IT (n = 10), carboplatin IV (n = 11) or bleomycin IV (n = 23). Treatment response according to RECIST criteria was recorded at 2 and 4 weeks post-treatment, and patients were followed until disease progression and/or death. All three groups were comparable regarding age, sex, weight, and lesion size. Adverse events were generally mild, localised and similar between groups. ORRs were 90.0% (carboplatin IV + IT), 90.9% (carboplatin IV) and 95.6% (bleomycin IV) and were not significantly different (p = 0.79). Median PFI was not reached for carboplatin IV + IT or carboplatin IV and was 566 days for bleomycin IV, with no significant difference between the three groups (p = 0.81). This study suggests that ECT using IV or IV + IT carboplatin is a reasonable alternative therapeutic option for managing cSCC, and further studies are warranted to compare outcomes between treatment protocols.

Practical Principles of Palliative Care in Veterinary Oncology: Alleviating the Suffering of the Animal, Owner, and Veterinarian

Background

Palliative care for pets is a developing area that encompasses animals with cancer and other chronic and degenerative diseases.

Objectives

To elucidate the guiding principles of palliative care in veterinary oncology.

Methods

This article was structured from an extensive literature review and addresses the growing need for improved palliative care in veterinary medicine. Methods of quality of life assessment in animals with cancer, owner education, and the importance of an interdisciplinary team approach are discussed.

Results

Palliative care aims to improve the animal's quality of life, alleviating its physical, emotional, and social suffering. Through attentive communication, palliative care also seeks to alleviate owners suffering from the moment of diagnosis to mourning the patient's death.

Conclusions

The importance of offering palliative care alongside anticancer techniques and treatments should not be underestimated and should ideally use a multidisciplinary team approach.

Multimodal Blockade of the Renin-Angiotensin System in the Treatment of Cancer in Dogs Has Mild Adverse Effects in Some Dogs

The renin-angiotensin system (RAS) is increasingly being recognized to play a role in the tumor microenvironment, promoting tumor growth. Studies blocking a single part of the RAS have shown mixed results, possibly due to the existence of different bypass pathways and redundancy within the RAS. As such, multimodal blockade of the RAS has been developed to exert more complete inhibition of the RAS. The aim of the present study was to assess the safety of multimodal RAS blockade in dogs. Five dogs (four with appendicular osteosarcoma, one with oral malignant melanoma) were treated with atenolol, benazepril, curcumin, meloxicam, and metformin. The dogs underwent clinical examination, blood pressure measurement, and hematology and serum biochemistry tests performed at 0, 1, 3, 6, 9, and 12 weeks, then every 3 months thereafter. End-of-life decisions were made by the owners. None of the dogs developed hypotension. One dog had intermittent vomiting during the 64 weeks it was on the trial. One dog had a one-off increase in serum SDMA(symmetrical dimethylarginine) concentration. Dogs were euthanized at weeks 3 (osteosarcoma), 10 (osteosarcoma), 17 (osteosarcoma), and 26 (oral malignant melanoma), and one dog was still alive at the end of the trial at 64 weeks (osteosarcoma). This is the first assessment of multimodal blockade of the RAS in dogs, and the results suggest it causes only mild adverse effects in some animals. The efficacy of the treatment was not assessed due to the small number of dogs. This pilot study allows for future larger studies assessing multimodal RAS blockade for the treatment of canine cancer.

Safety and efficacy of a ribose-cysteine supplement to increase erythrocyte glutathione concentration in healthy dogs

OBJECTIVE

To evaluate the safety of oral administration of a d-ribose-l-cysteine (RibCys) supplement to dogs and the effect of this supplementation on erythrocyte glutathione (GSH) concentration.

ANIMALS

24 healthy adult dogs.

PROCEDURES

In a randomized, double-blinded, controlled trial, dogs received 500 mg of a RibCys supplement or placebo (n = 12/group), PO, every 12 hours for 4 weeks. Dogs were evaluated weekly by means of a physical examination, CBC, serum biochemical analysis, urinalysis, and owner-completed quality-of-life questionnaire. Erythrocyte GSH concentration was measured on day 0 (ie, the day before treatment began) and weekly during supplementation.

RESULTS

No dose-limiting adverse effects were noted in any dog. Two dogs in each group had mild, self-limiting diarrhea and anemia. No significant increase in erythrocyte GSH concentration was noted in either group at any time point. Two dogs in the RibCys group had improved skin and coat health and improved clinical signs of osteoarthritis. No clinical or owner-perceived improvements were noted in the placebo group.

CONCLUSIONS AND CLINICAL RELEVANCE

The RibCys supplement was safe and well tolerated in all dogs. Owners reported improvements in dermatologic and orthopedic conditions in some dogs in the RibCys group. No significant differences were observed in erythrocyte GSH concentration before or after RibCys treatment. This lack of significant differences may have been attributable to the use of healthy dogs, which would not be expected to have depleted GSH concentrations. Given the observed safety profile of RibCys, additional research is warranted to explore the potential usefulness of RibCys supplementation in dogs with cancer and those undergoing treatment for cancer.

A systematic review of the quality of life assessment tools for cats in the published literature

Quality of life (QoL) is an important parameter to assess in cats, as it can be pivotal to important decision-making. Research reports that owners of cats with heart disease would trade longevity for QoL, and treatment associated improvement in QoL is very important for cats with chronic kidney disease. This systematic review aimed to explore the published literature to identify the number and range of QoL assessment tools available to researchers and veterinary professionals, by discovering tools which have already been used in published studies. Medline and CAB Abstracts were searched in March 2018, using terms relevant to cats and QoL or well-being. Inclusion and exclusion criteria were applied and information on uniqueness, validation and a short description of each tool extracted. A total of 1138 manuscripts were identified, of which 96 met all criteria. Forty of 96 manuscripts contained an assessment of QoL, using one of 32 unique tools identified. Sixteen of the tools identified were structured, making detailed patient assessments. Only eight of the structured tools were validated, and of these, three could be applied to healthy cats; the remainder being specific to a disease or being hospitalised. Some validated tools appeared in more than one manuscript. Overall, 12 manuscripts used a validated tool. In the 16 unstructured tools, five tools assessed QoL by assigning a single word (e.g. 'poor'). Eight tools assessed QoL on a single Likert scale (e.g. a number between 1 and 5). This work identifies the tools that are currently available for the assessment of QoL by researchers and veterinary professionals. Additionally, it demonstrates that many are not validated or lack detailed animal assessment, highlighting that further work in this important area is needed.

Plasma Cytokeratin 18 and fecal Alpha-1 Antitrypsin concentrations in dogs with osteosarcoma receiving carboplatin chemotherapy

Gastrointestinal (GI) toxicosis is a common side effect of cytotoxic chemotherapy treatment in humans and dogs. Measurement of cytokeratin 18 (CK18), an intracellular structural protein released during epithelial apoptosis, and Alpha1‐Antitrypsin (A1AT) in faeces provides a mechanism for evaluating damage to the intestinal mucosa secondary to cytotoxic chemotherapy. Our goal was to evaluate the clinical utility of plasma CK18 and faecal A1‐AT levels as non‐invasive biomarkers of cytotoxic chemotherapy induced GI toxicity. We conducted a prospective cohort study in dogs (N = 10) with osteosarcoma undergoing amputation followed by carboplatin chemotherapy. We hypothesized that plasma CK18 and faecal A1‐AT levels would increase following carboplatin administration due to drug‐induced GI epithelial damage/apoptosis, and that plasma CK18 and faecal A1‐AT levels would correlate with severity of GI toxicity. Mean baseline plasma CK18 concentration was variable amongst patients; however, CK18 concentration prior to carboplatin chemotherapy treatment was not significantly different from CK18 levels after treatment. There was significant intra and inter‐patient variability in mean faecal A1‐AT levels at baseline. Mean A1‐AT concentration did not change significantly from day 0 to day 21. Gastrointestinal toxicity was minimal; therefore, we were unable to determine the association of plasma CK18 and faecal A1‐AT concentrations with development of GI toxicosis. In this study population, plasma CK18 and faecal A1‐AT concentration were not clinically useful biomarkers for the detection of GI toxicosis secondary to carboplatin administration. Further prospective evaluation of CK18 and A1‐AT as biomarkers of drug‐induced GI toxicity is warranted in a larger cohort of dogs receiving cytotoxic chemotherapy.

AVMA clinical trial registration number: AAHSD004827.

Anorexia and the Cancer Patient

Appetite influences perceived quality of life for a dog or cat with cancer. Inappetence often is multifactorial, complicating treatment. Cancer-related anorexia/cachexia syndrome is a metabolic, paraneoplastic syndrome characterized by decreased food intake, involuntary weight loss, and loss of fat and muscle. If weight loss/cachexia has an impact on canine and feline cancer patients as in humans, management may improve survival times and quality of life. The challenge is having effective, proved therapies available for clinical use. Recent Food and Drug Administration approvals for appetite stimulation have renewed interest and discussion and has the potential to alter the course of case management.

Retrospective survey of owners' experiences with palliative radiation therapy for pets

OBJECTIVE To describe animal owners' experiences with palliative radiation therapy (PRT) of pets and identify factors influencing satisfaction with their pets' treatment. DESIGN Retrospective, cross-sectional study. SAMPLE 118 owners of dogs, cats, or rabbits. PROCEDURES Medical records were searched to identify animals that underwent PRT between 2004 and 2013. Signalment, tumor-related data, and outcome information were recorded. Owners completed an electronic survey assessing satisfaction with treatment (ie, satisfaction with the decision for their pet to undergo PRT and indication that they would choose PRT for their pet again), expectations regarding PRT, and perceptions of their pets' quality of life (QOL) and signs of discomfort from acute adverse radiation effects. Additional data regarding practical aspects of treatment, pet death, communications with veterinarians, and owner demographics were collected. Variables were tested for association with measures of owner satisfaction. RESULTS 92 of 116 (79%) owners were satisfied with the decision to have their pets undergo PRT. Most (92/118 [78%]) owners reported their pet's QOL improved after PRT; these owners were significantly more likely to be satisfied than those who did not report improved QOL. Owners who perceived their pets had discomfort from adverse radiation effects (38/116 [33%]) were significantly less likely to be satisfied than owners who did not report this observation. Measures of satisfaction were not associated with patient survival time. Twenty-one of 118 (18%) owners indicated they expected PRT would cure their pet's tumor. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that short life expectancy should not deter recommendation of PRT for pets. Protocols that minimize risk of acute adverse effects may be advantageous. Veterinarians should attempt to ensure that owners understand the goals of PRT.

Owner perceptions of radiotherapy treatment for veterinary patients with cancer

Veterinary clients may have trepidation about treating their pet with radiotherapy because of concerns about radiation side effects or repeated anaesthetics. The purpose of this study is to assess whether owners' attitudes towards veterinary radiotherapy, including concerns over side effects, change during the course of treatment, and whether radiotherapy was perceived to affect pets' quality of life (QOL). A prospective cohort study of clients from 2012 to 2015 was performed. Pets received palliative or definitive radiotherapy for various tumours. Clients completed questionnaires before, during and after radiotherapy. Questions assessed owner preconceptions before treatment, including side effect expectations, actual side effects experienced and overall satisfaction with the process. In addition, at each time point, the owners assessed their pet's QOL using a simple numerical scale. Forty-nine patients were included. After completing treatment, owners were significantly less concerned about potential side effects of radiotherapy (P < 0.001), side effects associated with repeat anaesthetics (P < 0.001), and about radiotherapy in general (P < 0.001). QOL did not show a significant change at any point during or after treatment. Following treatment, 94% reported that the experience was better than expected and 100% supported the use of radiotherapy in pets. This is the first prospective study evaluating client attitudes and satisfaction before and after radiotherapy treatment in pets. The results indicate that radiotherapy is well tolerated, and the anxiety associated with radiotherapy is significantly alleviated after experiencing the process. These results will help veterinarians allay client concerns, and will hopefully lead to an increase in clients pursuing radiotherapy in pets.

Owners' perception of their dogs' quality of life during and after radiotherapy for cancer

OBJECTIVES

To determine the owners' perception of dogs' quality of life before, immediately after and 6 weeks after radiotherapy treatments for a variety of neoplasms and assess owner satisfaction over their decision to treat.

MATERIALS AND METHODS

Questionnaires were given to owners whose dogs completed a radiotherapy treatment at a referral radiation oncology centre. Questionnaires were given at three time points: before treatment, on the last day of treatment and more than 6 weeks after the treatment was finished. Owners were asked questions regarding their perception of radiotherapy and the quality of life of their pets before, during and after treatment with radiation therapy. Quality of life was scored from 1 (could not be worse) to 10 (could not be better).

RESULTS

Seventy-one owners met the inclusion and exclusion criteria. Results showed that 6 weeks or more after treatment, most owners were happy that they had chosen to treat their dogs (92%) and would treat another pet again, if indicated (88%). Across the three time points, median quality of life perception score was 9.

CLINICAL SIGNIFICANCE

Radiotherapy was well tolerated by owners and dogs in this study. The great majority of clients were happy to have pursued radiotherapy, would choose to do it again (if indicated) and would recommend it to a friend.

Use of accelerometry to investigate physical activity in dogs receiving chemotherapy

OBJECTIVES

To perform a preliminary study to assess whether single-agent palliative or adjuvant chemotherapy has an impact on objectively measured physical activity in dogs.

METHODS

Fifteen dogs with neoplasia (treatment group) wore ActiGraph™ accelerometers for 5-day periods before, during and after receiving single-agent adjuvant or palliative chemotherapy. Mean 5-day total physical activity and time spent in three different intensities of activity (sedentary, light-moderate and vigorous) before, during and after receiving chemotherapy were compared to a group of 15 healthy dogs (control group). Results were also compared within the treatment group across time.

RESULTS

Prior to chemotherapy, treated dogs tended to be less active than control dogs. Treatment group dogs were slightly more active at restaging than they were prior to treatment but had similar activity levels to control dogs. Marked effects of chemotherapy on physical activity were not detected. Physical activity was slightly lower in treated dogs during chemotherapy when compared to control dogs but there was a slight increase in physical activity of treated dogs during chemotherapy when compared with pretreatment recordings. There was little change in the mean 5-day total physical activity between treated dogs during chemotherapy and at restaging but a mild decrease in time spent sedentary and increase in time spent in light-moderate activity at this comparison of time points.

CLINICAL SIGNIFICANCE

Single-agent adjuvant or palliative chemotherapy had minimal impact on physical activity levels in dogs with neoplasia.

Quality of life assessment in dogs and cats receiving chemotherapy - a review of current methods

This study aimed to review currently reported methods of assessing the effects of chemotherapy on the quality of life (QoL) of canine and feline patients and to explore novel ways to assess QoL in such patients in the light of the experience to date in human pediatric oncology. A qualitative comparative analysis of published papers on the effects of chemotherapy on QoL in dogs and cats were conducted. This was supplemented with a comparison of the parameters and domains used in veterinary QoL-assessments with those used in the Pediatric Quality of Life Inventory (PedsQL^™ ) questionnaire designed to assess QoL in toddlers. Each of the identified publications including QoL-assessment in dogs and cats receiving chemotherapy applied a different method of QoL-assessment. In addition, the veterinary QoL-assessments were mainly focused on physical clinical parameters, whereas the emotional (6/11), social (4/11) and role (4/11) domains were less represented. QoL-assessment of cats and dogs receiving chemotherapy is in its infancy. The most commonly reported method to assess QoL was questionnaire based and mostly included physical and clinical parameters. Standardizing and including a complete range of potentially relevant parameters in future QoL assessments may benefit owner decision making.

Species differences in tumour responses to cancer chemotherapy

Despite advances in chemotherapy, radiotherapy and targeted drug development, cancer remains a disease of high morbidity and mortality. The treatment of human cancer patients with chemotherapy has become commonplace and accepted over the past 100 years. In recent years, and with a similar incidence of cancer to people, the use of cancer chemotherapy drugs in veterinary patients such as the dog has also become accepted clinical practice. The poor predictability of tumour responses to cancer chemotherapy drugs in rodent models means that the standard drug development pathway is costly, both in terms of money and time, leading to many drugs failing in Phase I and II clinical trials. This has led to the suggestion that naturally occurring cancers in pet dogs may offer an alternative model system to inform rational drug development in human oncology. In this review, we will explore the species variation in tumour responses to conventional chemotherapy and highlight our understanding of the differences in pharmacodynamics, pharmacokinetics and pharmacogenomics between humans and dogs. Finally, we explore the potential hurdles that need to be overcome to gain the greatest value from comparative oncology studies.

Quality of life measurement in prospective studies of cancer treatments in dogs and cats

BACKGROUND

Quality of life (QOL) is an important consideration in healthcare decision-making for pets with cancer. To determine the effect of disease and treatment on pet QOL, this important variable should be objectively measured as an outcome in veterinary cancer studies.

OBJECTIVES

To determine the prevalence and methodology of QOL measurement in a sample of recently published reports of prospective studies evaluating cancer treatments in client-owned dogs and cats; to characterize reporting of QOL outcomes and to identify article characteristics associated with QOL measurement.

METHODS

English-language reports of prospective studies of cancer treatments in dogs and cats published from 2008 to 2013 were identified using medical research databases combined with a hand-searching strategy. Data pertaining to general article characteristics and QOL measurement were abstracted and summarized.

RESULTS

Reports of 144 eligible studies were identified. QOL was measured in 16 (11.1%) studies, with 8 (5.6%) reporting the results. All studies that measured QOL reported using unvalidated instruments, or did not report how QOL was assessed. Only 1 study provided sufficient information for QOL measurements to be replicated. Recently published articles (2011-2013) were significantly more likely to report measuring QOL, compared with earlier articles.

CONCLUSIONS

Quality of life of pets undergoing cancer treatment is largely unreported and cannot be meaningfully compared across treatments or disease states using the existing literature. Reliable, validated instruments are needed to facilitate the measurement and comparison of pet QOL in veterinary cancer research. Consistent reporting practices could improve transparency and interpretation of QOL results.

A survey of owners' perceptions and experiences of radioiodine treatment of feline hyperthyroidism in the UK

The efficacy of radioiodine treatment of feline hyperthyroidism is well established; however, limited information is known about owners' perceptions or experiences of radioiodine. This study aimed to examine factors that influence owner treatment choices and their opinions following radioiodine. Surveys were sent to owners of cats referred for radioiodine treatment between 2002 and 2011 (radioiodine group; 264 cats) and owners of non-radioiodine-treated hyperthyroid cats seen at first-opinion practices (control group; 199 cats). The response rate was 67.0% (310 returned: 175 radioiodine, 135 control). Of 135 controls, 72 (53.3%) were unaware of radioiodine as a treatment option. Owners of cats ⩾15 years old and uninsured cats were less likely to pursue radioiodine. Cost of treatment, travel distance, potential human or animal health risks and waiting periods for radioiodine had a low impact on owners' treatment choice. Owners reported a moderate level of concern about treatment hospitalisation length, which included (158 respondents) the possibility of the cat being unhappy 130 (82.3%), owner missing the cat 102 (64.6%), inappetence 50 (31.6%), other pets missing the cat 32 (20.3%), development of co-morbid disease 28 (17.7%) and side effects 25 (15.8%). Owners assessed their cat's quality of life on a scale of 1 (very poor) to 10 (excellent), as 4 (4) (median [interquartile range]) pre-radioiodine (134 respondents) and 9 (2) post-radioiodine (131 respondents). Of 132 respondents, 121 (91.7%) were happy with their decision to choose radioiodine. The results of this questionnaire may assist veterinarians in addressing common owner concerns when discussing radioiodine as a treatment option for hyperthyroidism.

Questionnaire-based assessment of owner concerns and doctor responsiveness: 107 canine chemotherapy patients

OBJECTIVE

To quantify owner concerns regarding clinical signs in canine patients receiving chemotherapy and to assess degree of concordance between client and veterinarian concerns regarding patient quality of life.

METHODS

Retrospective analysis of owner-reported concerns during chemotherapy treatment. Owner-reported adverse events were recorded sequentially for each patient through a partially open design questionnaire and correlated with veterinary patient summaries for each visit. Canine patients treated for transitional cell carcinoma, haemangiosarcoma, malignant melanoma or osteosarcoma were eligible for inclusion. Minimum treatment eligibility was two chemotherapy treatments given in 21-day protocol cycles, with a maximum of six treatment cycles recorded.

RESULTS

A total of 553 evaluable visits, seen by 18 oncology clinicians, were assessed. Owners expressed concern before chemotherapy in 48% of visits. Owner concerns at the first visit did not differ significantly from those expressed at the sixth visit. Remission status was a significant factor in owners' rate of reporting concerns. Diarrhoea grade was associated with owners' concerns. Clinician gender was not associated with responsiveness to owners' concerns.

CLINICAL SIGNIFICANCE

Questionnaire-based surveys appear to be an effective tool for communicating dog owners' concerns regarding chemotherapy and potentially for monitoring a clinician's attentiveness. Owners expressed concerns at approximately half of chemotherapy appointments.