Clinicians' experiences with cancer patients living longer with incurable cancer: a focus group study in the Netherlands

AIM

To explore (1) experiences of primary care physicians (PCPs) and oncological medical specialists about providing care to patients living longer with incurable cancer, and (2) their preferences concerning different care approaches (palliative support, psychological/survivorship care support).

BACKGROUND

At present, oncological medical specialists as well as PCPs are exploring how to improve and better tailor care to patients living longer with incurable cancer. Our previous study at the in-patient oncology unit showed that patients living longer with incurable cancer experience problems in how to deal with a prognosis that is insecure and fluctuating. To date, it could be argued that treating these patients can be done with a 'palliative care' or a 'survivorship/psychosocial care' approach. It is unknown what happens in actual medical practice.

METHODS

We performed multidisciplinary group meetings: 6 focus groups (3 homogenous groups with PCPs (n = 15) and 3 multidisciplinary groups (n = 17 PCPs and n = 6 medical specialists) across different parts of the Netherlands. Qualitative data were analysed with thematic analysis.

FINDINGS AND CONCLUSIONS

In the near future, PCPs will have an increasing number of patients living longer with incurable cancer. However, in a single PCP practice, the experience with incurable cancer patients remains low, partly because patients often prefer to stay in contact with their medical specialist. PCPs as well as medical specialists show concerns in how they can address this disease phase with the right care approach, including the appropriate label (e.g. palliative, chronic, etc.). They all preferred to be in contact early in the disease process, to be able to discuss and take care for the patients' physical and psychological well-being. Medical specialists can have an important role by timely referring their patients to their PCPs. Moreover, the disease label 'chronic' can possibly assist patients to live their life in the best possible way.

RNA Biomarkers as a Response Measure for Survival in Patients with Metastatic Castration-Resistant Prostate Cancer

Treatment evaluation in metastatic castration-resistant prostate cancer is challenging. There is an urgent need for biomarkers to discriminate short-term survivors from long-term survivors, shortly after treatment initiation. Thereto, the added value of early RNA biomarkers on predicting progression-free survival (PFS) and overall survival (OS) were explored. The RNA biomarkers: KLK3 mRNA, miR-375, miR-3687, and NAALADL2-AS2 were measured in 93 patients with mCRPC, before and 1 month after start of first-line abiraterone acetate or enzalutamide treatment, in two prospective clinical trials. The added value of the biomarkers to standard clinical parameters in predicting PFS and OS was tested by Harell's C-index. To test whether the biomarkers were independent markers of PFS and OS, multivariate Cox regression was used. The best prediction model for PFS and OS was formed by adding miR-375 and KLK3 (at baseline and 1 month) to standard clinical parameters. Baseline miR-375 and detectable KLK3 after 1 month of therapy were independently related to shorter PFS, which was not observed for OS. In conclusion, the addition of KLK3 and miR-375 (at baseline and 1 month) to standard clinical parameters resulted in the best prediction model for survival assessment.

Liquid biopsy reveals KLK3 mRNA as a prognostic marker for progression free survival in patients with metastatic castration-resistant prostate cancer undergoing first-line abiraterone acetate and prednisone treatment

Circulating RNAs extracted from liquid biopsies represent a promising source of cancer‐ and therapy‐related biomarkers. We screened whole blood from patients with metastatic castration‐resistant prostate cancer (mCRPC) following their first‐line treatment with abiraterone acetate and prednisone (AA‐P) to identify circulating RNAs that may correlate with progression‐free survival (PFS). In a prospective multicenter observational study, 53 patients with mCRPC were included after they started first‐line AA‐P treatment. Blood was drawn at baseline, 1, 3, and 6 months after treatment initiation. The levels of predefined circulating RNAs earlier identified as being upregulated in patients with mCRPC (e.g., microRNAs, long noncoding RNAs, and mRNAs), were analyzed. Uni‐ and multivariable Cox regression and Kaplan–Meier analyses were used to analyze the prognostic value of the various circulating RNAs for PFS along treatment. Detectable levels of kallikrein‐related peptidase 3 (KLK3) mRNA at baseline were demonstrated to be an independent prognostic marker for PFS (201 vs 501 days, P = 0.00054). Three months after AA‐P treatment initiation, KLK3 could not be detected in the blood of responding patients, but was still detectable in 56% of the patients with early progression. Our study confirmed that KLK3 mRNA detection in whole blood is an independent prognostic marker in mCRPC patients receiving AA‐P treatment. Furthermore, the levels of circulating KLK3 mRNA in patients receiving AA‐P treatment might reflect treatment response or early signs of progression.

Prognostic Value of Novel Liquid Biomarkers in Patients with Metastatic Castration-Resistant Prostate Cancer Treated with Enzalutamide: A Prospective Observational Study

BACKGROUND

Several treatment options were recently added for metastatic castration-resistant prostate cancer (mCRPC). However, response to therapy is variable, and biomarkers that can guide treatment selection and response evaluation are lacking. Circulating RNAs are a promising source of biomarkers. We explored messenger RNAs (mRNAs), microRNAs (miRNAs), and long noncoding RNAs (lncRNAs) as potential biomarkers in liquid biopsies of patients with mCRPC treated with enzalutamide.

METHODS

Forty patients were included in this prospective multicenter observational study. Whole blood was drawn at baseline and 1, 3, and 6 months after start of therapy. Four mRNAs, 6 miRNAs, and 5 lncRNAs were analyzed by quantitative PCR. RNA levels in 30 healthy individuals were used as controls. RNA expression data were analyzed by Kaplan-Meier and Cox regression analyses, and the primary end point was progression-free survival. Clinical factors were included in the multivariable Cox regression analysis.

RESULTS

Levels of 2 miRNAs, miR-375 and miR-3687, and 1 lncRNA, N-acetylated alpha-linked acidic dipeptidase like 2 antisense RNA 2 (NAALADL2-AS2), were more than 2-fold higher in patients with mCRPC compared with healthy volunteers. Patients with higher levels of miR-375 or miR-3687 showed a shorter time to progression. Patients with higher levels of NAALADL2-AS2 showed a longer time to progression. In the multivariable Cox regression analysis, higher miR-375, miR-3687 and serum prostate-specific antigen concentrations were shown to be independent predictors for shorter time to progression.

CONCLUSIONS

We identified miR-3687 as a novel prognostic marker for response in patients with CRPC treated with enzalutamide, and we confirmed the prognostic value of miR-375.

Abstract 1413: Exploring the prognostic value of microRNAs and drug exposure in patients with metastatic castration resistant prostate cancer treated with abiraterone: a prospective observational study

Background Abiraterone acetate is registered for treatment of metastatic prostate cancer, including those with castration-resistant disease (mCRPC). Although it improves overall survival and progression free survival (PFS), treatment response differs between patients. Biomarkers to predict treatment response are lacking. Liquid biopsies containing microRNAs (miRNAs) are a promising source of prognostic biomarkers in mCRPC patients. Furthermore, the exposure to abiraterone in plasma is highly variable and subtherapeutic exposure might contribute to the variability in response to therapy. We explored the prognostic value of microRNAs and drug exposure in mCRPC patients treated with abiraterone.

Methods In a prospective multi-center observational study, 53 patients with mCRPC were included who started pre-chemotherapy abiraterone treatment. Blood was drawn at baseline, 1, 3 and 6 months after start of treatment. The following predefined miRNAs were selected; miR-21, miR-141, miR-200a, miR-200c, miR-375, miR-3687 and abiraterone concentrations were measured. MiRNA-levels in 30 healthy individuals served as controls. Relative miRNA-levels were calculated by the ΔΔCt method. If the geometric mean of a miRNA was more than 2-fold higher in patients versus healthy controls, they were included for survival analysis. Ctrough levels after 1, 3 and 6 months of therapy were measured. The average Ctrough level per patient was used for further analysis. The prognostic value of miRNAs and drug exposure for PFS (radiographic, biochemical or clinical progression) was analyzed with Kaplan-Meier (KM) analysis and tested with a log-rank test. Cut-off values for miRNAs in KM analysis were calculated using maximally selected rank statistics and for the relation with abiraterone Ctrough the earlier defined threshold of 8.4ng/ml was used.

Results Of the miRNAs analyzed, miR-375 was more than 2-fold higher in mCRPC patients versus healthy controls. Patients with more than 2.16 fold higher miR-375 compared to healthy controls showed a trend towards shorter PFS, median 352 vs. 456 days (p=0.076). No PFS benefit was shown for patients with a mean abiraterone Ctrough concentration ≥8.4ng/ml compared to patients below this threshold, median 411 vs. 409 days (p=0.81).

Conclusion High levels of miR-375 might be a prognostic biomarker for PFS in patients with mCRPC treated with abiraterone. The prognostic value of this miRNA should be further explored in a larger cohort of patients. Additionally, the functionality of miR-375 should be further elucidated. The beneficial effect of higher abiraterone exposure levels could not be confirmed in this study for this patient population.

Citation Format: Emmy Boerrigter, Guillemette E. Benoist, Inge M. van Oort, Gerald W. Verhaegh, Onno van Hooij, Levi Groen, Frank Smit, Irma M. Oving, Pieter de Mol, Tineke J. Smilde, Diederik M. Somford, Niven Mehra, Jack A. Schalken, Nielka P. van Erp. Exploring the prognostic value of microRNAs and drug exposure in patients with metastatic castration resistant prostate cancer treated with abiraterone: a prospective observational study [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1413.

Experiences of general practitioners and medical specialists with incurable cancer patients with a protracted disease trajectory: A focus group study

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Background: Advances in oncology have resulted in prolonged disease trajectories in patients with incurable cancer. In this disease-phase, patients are aware that cancer is incurable but they do not approach the last phase-of-life yet. We examined experiences and wishes of GPs and specialists concerning appropriate care-provision, delivered by GPs. Methods: We performed 6 focus groups in different regions in the Netherlands; 3 homogenous groups (N=15 GPs) and 3 heterogenous groups (N=23 GPs and medical specialists). Data were analysed with thematic content-analysis. Results: During the first focus-groups, the protracted disease phase was not acknowledged as a separate one; in the last focus-groups, however, this disease-phase received more attention. Physicians clearly distinghuished this trajectory from the palliative / terminal disease phase, partly because many patients did not experience severe physical problems. Most GPs preferred to be involved in the care of these patients as this would enable them to easily guide patients in their last phase-of-life. In these patients, GPs experienced difficulties in estimation of prognosis and advice of further treatment, partly because of insecurity of treatment side-effects of immunotherapy. Further, many physicians experienced difficulties in labeling this disease phase. ‘Stable’; ‘chronic’; and ‘Phase X’ were regularly mentioned. Medical specialists were more frequent involved with these patients but preferred to involve GPs as much as possible. They however also realised that this would become more difficult in future, given the growing group of patients in this disease phase. Conclusions: In the protracted disease phase, patients often do not experience severe physical symptoms. They often do not approach their patient for possible psycho-social problems. Apart from medical specialists, tools to easily communicate across specialties to optimise care need to be further explored.

Physical activity at altitude: challenges for people with diabetes: a review

BACKGROUND

A growing number of subjects with diabetes take part in physical activities at altitude such as skiing, climbing, and trekking. Exercise under conditions of hypobaric hypoxia poses some unique challenges on subjects with diabetes, and the presence of diabetes can complicate safe and successful participation in mountain activities. Among others, altitude can alter glucoregulation. Furthermore, cold temperatures and altitude can complicate accurate reading of glucose monitoring equipment and storage of insulin. These factors potentially lead to dangerous hyperglycemia or hypoglycemia. Over the last years, more information has become available on this subject.

PURPOSE

To provide an up-to-date overview of the pathophysiological changes during physical activity at altitude and the potential problems related to diabetes, including the use of (continuous) blood glucose monitors and insulin pumps. To propose practical recommendations for preparations and travel to altitude for subjects with diabetes.

DATA SOURCES AND SYNTHESIS

We researched PubMed, medical textbooks, and related Internet sites, and extracted human studies and data based on relevance for diabetes, exercise, and altitude.

LIMITATIONS

Given the paucity of controlled trials regarding diabetes and altitude, we composed a narrative review and filled in areas lacking diabetes-specific studies with data obtained from nondiabetic subjects.

CONCLUSIONS

Subjects with diabetes can take part in activities at high, and even extreme, altitude. However, careful assessment of diabetes-related complications, optimal preparation, and adequate knowledge of glycemic regulation at altitude and altitude-related complications is needed.

Exercise and type 2 diabetes mellitus: changes in tissue-specific fat distribution and cardiac function

PURPOSE

To prospectively assess the effects of an exercise intervention on organ-specific fat accumulation and cardiac function in type 2 diabetes mellitus.

MATERIALS AND METHODS

Written informed consent was obtained from all participants, and the study protocol was approved by the medical ethics committee. The study followed 12 patients with type 2 diabetes mellitus (seven men; mean age, 46 years ± 2 [standard error]) before and after 6 months of moderate-intensity exercise, followed by a high-altitude trekking expedition with exercise of long duration. Abdominal, epicardial, and paracardial fat volume were measured by using magnetic resonance (MR) imaging. Cardiac function was quantified with cardiac MR, and images were analyzed by a researcher who was supervised by a senior researcher (4 and 21 years of respective experience in cardiac MR). Hepatic, myocardial, and intramyocellular triglyceride (TG) content relative to water were measured with proton MR spectroscopy at 1.5 and 7 T. Two-tailed paired t tests were used for statistical analysis.

RESULTS

Exercise reduced visceral abdominal fat volume from 348 mL ± 57 to 219 mL ± 33 (P < .01), and subcutaneous abdominal fat volume remained unchanged (P = .9). Exercise decreased hepatic TG content from 6.8% ± 2.3 to 4.6% ± 1.6 (P < .01) and paracardial fat volume from 4.6 mL ± 0.9 to 3.7 mL ± 0.8 (P = .02). Exercise did not change epicardial fat volume (P = .9), myocardial TG content (P = .9), intramyocellular lipid content (P = .3), or cardiac function (P = .5).

CONCLUSION

A 6-month exercise intervention in type 2 diabetes mellitus decreased hepatic TG content and visceral abdominal and paracardial fat volume, which are associated with increased cardiovascular risk, but cardiac function was unaffected. Tissue-specific exercise-induced changes in body fat distribution in type 2 diabetes mellitus were demonstrated in this study.

Metabolic effects of high altitude trekking in patients with type 2 diabetes

OBJECTIVE

Limited information is available regarding the metabolic effects of high altitude trekking in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Thirteen individuals with type 2 diabetes took part in a 12-day expedition to the summit of Mount Toubkal (altitude, 4,167 m), Morocco, after 6 months of exercise training. Energy expenditure, body weight, blood glucose, fasting insulin, lipids, and HbA(1c) were assessed.

RESULTS

Training reduced fasting glucose (-0.7 ± 0.9 mmol/L, P = 0.026) and increased exercise capacity (+0.3 ± 0.3 W/kg, P = 0.005). High altitude trekking decreased fasting insulin concentrations (-3.8 ± 3.2 μU/L, P = 0.04), total cholesterol (-0.7 ± 0.8 mmol/L, P = 0.008), and LDL cholesterol (-0.5 ± 0.6 mmol/L, P = 0.007).

CONCLUSIONS

High altitude trekking preceded by exercise training is feasible for patients with type 2 diabetes. It improves blood glucose, lipids, and fasting insulin concentrations, while glucose control is maintained.

Increased insulin requirements during exercise at very high altitude in type 1 diabetes

OBJECTIVE

Safe, very high altitude trekking in subjects with type 1 diabetes requires understanding of glucose regulation at high altitude. We investigated insulin requirements, energy expenditure, and glucose levels at very high altitude in relation to acute mountain sickness (AMS) symptoms in individuals with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Eight individuals with complication-free type 1 diabetes took part in a 14-day expedition to Mount Meru (4,562 m) and Mount Kilimanjaro (5,895 m) in Tanzania. Daily insulin doses, glucose levels, energy expenditure, and AMS symptoms were determined. Also, energy expenditure and AMS symptoms were compared with a healthy control group.

RESULTS

We found a positive relation between AMS symptoms and insulin requirements (r = 0.78; P = 0.041) and AMS symptoms and glucose levels (r = 0.86; P = 0.014) for Mount Kilimanjaro. Compared with sea level, insulin doses tended to decrease by 14.2% (19.7) (median [interquartile range]) (P = 0.41), whereas glucose levels remained stable up to 5,000 m altitude. However, at altitudes >5,000 m, insulin dose was unchanged (36.8 ± 17 vs. 37.6 ± 19.1 international units [mean ± SD] P = 0.75), but glucose levels (7.5 ± 0.6 vs. 9.5 ± 0.8 mmol/L [mean ± SD] P = 0.067) and AMS scores (1.3 ± 1.6 vs. 4.4 ± 4 points [mean ± SD] P = 0.091) tended to increase. Energy expenditure and AMS symptoms were comparable in both groups (P = 0.84).

CONCLUSIONS

Our data indicate that in complication-free individuals with type 1 diabetes, insulin requirements tend to increase during altitudes above 5,000 m despite high energy expenditure. This change may be explained, at least partly, by AMS.

Accuracy of handheld blood glucose meters at high altitude

Background

Due to increasing numbers of people with diabetes taking part in extreme sports (e.g., high-altitude trekking), reliable handheld blood glucose meters (BGMs) are necessary. Accurate blood glucose measurement under extreme conditions is paramount for safe recreation at altitude. Prior studies reported bias in blood glucose measurements using different BGMs at high altitude. We hypothesized that glucose-oxidase based BGMs are more influenced by the lower atmospheric oxygen pressure at altitude than glucose dehydrogenase based BGMs.

Methodology/Principal Findings

Glucose measurements at simulated altitude of nine BGMs (six glucose dehydrogenase and three glucose oxidase BGMs) were compared to glucose measurement on a similar BGM at sea level and to a laboratory glucose reference method. Venous blood samples of four different glucose levels were used. Moreover, two glucose oxidase and two glucose dehydrogenase based BGMs were evaluated at different altitudes on Mount Kilimanjaro. Accuracy criteria were set at a bias <15% from reference glucose (when >6.5 mmol/L) and <1 mmol/L from reference glucose (when <6.5 mmol/L). No significant difference was observed between measurements at simulated altitude and sea level for either glucose oxidase based BGMs or glucose dehydrogenase based BGMs as a group phenomenon. Two GDH based BGMs did not meet set performance criteria. Most BGMs are generally overestimating true glucose concentration at high altitude.

Conclusion

At simulated high altitude all tested BGMs, including glucose oxidase based BGMs, did not show influence of low atmospheric oxygen pressure. All BGMs, except for two GDH based BGMs, performed within predefined criteria. At true high altitude one GDH based BGM had best precision and accuracy.