What is an "early palliative care" intervention? A scoping review of controlled studies in oncology.

INTRODUCTION

Many patients with incurable cancer suffer from a wide range of physical symptoms and encounter psychological and social challenges associated with the disease as well as due to tumor‐specific treatment. 1 , 2 , 3 Palliative care (PC) contributes to the improved health of these patients by addressing their physical, psychosocial, and spiritual needs. While PC traditionally has been offered to patients in the last phase of life this approach has changed over the past few decades. In line with the definition of the World Health Organization, 4 it is nowadays recommended to offer PC at earlier stages of the disease trajectory and along with anti‐cancer treatment. 5

The concept of early PC (EPC) reflects this development. 6 , 7 , 8 , 9 The American Society of Clinical Oncology (ASCO), for example, recommends that patients with advanced cancer diagnosis should be offered EPC within 8 weeks after diagnosis. 5 Accordingly, EPC targets a broad range of patients, some of whom may only have a life expectancy of several weeks whereas others may have a life expectancy of several years.

Research suggests that EPC can have a positive impact on a range of outcomes, such as patients' quality of life, the severity of the symptoms experienced and even prolongation of life. 10 , 11 To date, however, the evidence is limited, since the certainty regarding the elicited positive effects is low to very low. 10 , 11 , 12 , 13 Moreover, there is lack of consensus regarding the best timing, elements, and mode of EPC. 5 This is also reflected in a more recent systematic review about EPC in hematological diseases which stresses the need to specify patient groups, the right time to start with early palliative care as well as the elements of care to provide EPC. 12 In a similar vein, distinguishing different care models to introduce EPC 7 and identifying those factors of EPC that contribute most to the improvement of the situations of patients with incurable cancer EPC 14 has been called for.

One reason for the current debate is the fact that EPC is a so‐called complex intervention which means that the intervention encompasses multiple treatment modalities that may contribute to the (different) effect(s). 15 , 16 , 17 Against this background a detailed knowledge about structure, processes, and targets of the intervention is important. However, to the best of our knowledge, no structured analysis of EPC interventions using an established instrument, such as the Template for Intervention Description and Replication (TIDieR), exists.

To be able to develop and evaluate EPC further, it is necessary to collect and critically appraise studies on commonalities and differences regarding the elements of EPC interventions, which possibly contribute to the effects of EPC. Moreover, given the broad range of patients with advanced cancer and their needs, clarification concerning the right type of EPC intervention for a specific patient group is important. Against this background, this scoping review aims to provide a detailed overview of the elements of EPC interventions, target groups, and reported outcome measures that have been used in controlled trials with cancer patients.

MATERIALS AND METHODS

We conducted a scoping review in a multidisciplinary team (medical ethicists, physicians with an expertise in oncology and PC, and a nursing scientist). We followed the steps described by Arkey & O'Malley 18 : (1) formulating the research question, (2) identifying relevant studies, (3) selecting relevant studies, (4) charting the data, and (5) collating, summarizing, and reporting the results.

We searched the following databases for available evidence up to February 2022:

MEDLINE via Pubmed

CINAHL via EBSCO

CENTRAL via Cochrane Library

Cochrane Pain, Palliative and Supportive Care Group (PAPAS) Database via Cochrane Library

We also screened the reference lists of all included articles for other relevant studies.

The search terms and combinations for each database were derived from previous reviews about this topic. 7 , 10 They are reported in adherence with the PRISMA‐S checklist 19 (see Data S1 ). The search terms were subject to internal quality assurance through the application of the Peer Review of Electronic Search Strategies checklist. 20 Deduplication of the results was performed by Citavi Version 6.6 21 and Rayyan software. 22

Studies were included if they were self‐labeled in title or abstract as “early palliative care” or its synonyms, if the respective study population was adult (≥18 years), and if the publication was written in Dutch, English, or German. We chose that language because we are fluent in those languages. A diverse range of study designs was included to gather a broad range of interventions. Randomized controlled trials, nonrandomized trials, cohort studies, and controlled before‐after studies were eligible for inclusion. We included studies conducted in hospitals or outpatient clinics, but we excluded studies focusing only on home care in order to be able to compare the interventions taking place within hospitals and further clinical settings. Control interventions could be either an active intervention designed for the study or usual care. We do not report outcomes in terms of the effectiveness of EPC due to the focus of this review on elements of the intervention and outcome measures.

Two reviewers (EG and SN) independently screened titles and abstracts and subsequently read the full texts of the papers thus identified. 22 A third author (JS) was consulted in case of dissent or uncertainty. The search flow was visualized with the PRISMA Flowchart. 23 The data were extracted by EG and SN independently, using a piloted form that included the following items: year of publication, country, setting, study design, funding, population (inclusion and exclusion criteria with a focus on the type and stage of cancer), outcomes and outcome measures. We used the TIDieR for the extraction of the information on the intervention and the control interventions. 24 We did not perform a risk of bias assessment because the aim of this review was to assess the content of the interventions and not the effectiveness of EPC, which is in line with the process described by Arksey & O'Malley. 18 We synthesized the data by means of a narrative and tabular overview of the data regarding study design, sample size, country, cancer entity, time until onset of EPC, outcomes measured, and the elements of the interventions. Although this review does not focus on the pooling of outcomes we decided to synthesize these data, because of information on the consistency of the described elements of EPC with the respective goals.

RESULTS

The database search yielded 3766 records. After deduplication, 2651 articles remained. Exclusion of 2397 articles was based on the screening of title and abstract. The assessment of the remaining 254 full‐text articles resulted in the inclusion of a total of 40 studies 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 for synthesis. See Figure 1 for details on the PRISMA Flowchart.

The publication dates ranged from 2009 to 2022. Six studies were cohort studies, 39 , 41 , 42 , 43 , 47 , 48 while the remainder were all randomized controlled trials. Sample sizes ranged from 23 30 to 969 41 patients (median = 156, mean = 208). The most prominent study countries were the USA ( n = 16), 25 , 26 , 27 , 32 , 33 , 34 , 37 , 39 , 41 , 47 , 50 , 51 , 55 , 56 , 57 , 60 Canada 30 , 46 , 63 , 64 ( n = 4) and Italy ( n = 3). 36 , 40 , 49 Table 1 provides an overview of the included studies.

Cancer diagnosis and the onset of early palliative care

Studies included in this review investigated outcomes of EPC for patients with a range of cancer entities, stages of disease, and other characteristics. Most studies included more than one diagnosis, whereas 10 studies 28 , 29 , 30 , 34 , 37 , 40 , 49 , 50 , 55 , 62 focused on patients with one cancer entity. Patients were most frequently diagnosed with pancreatic cancer ( n = 10) 31 , 35 , 36 , 40 , 41 , 50 , 52 , 56 , 61 , 64 and non‐small cell lung cancer ( n = 9). 25 , 29 , 35 , 36 , 39 , 55 , 56 , 57 , 62 Eight studies 25 , 29 , 38 , 39 , 45 , 47 , 63 , 64 used stage III or IV as inclusion criterion for specifying the status of disease, while others described the stage of disease eligible for ECP studies as “advanced” or “incurable.” 26 , 27 , 31 , 32 , 35 , 37 , 40 , 41 , 42 , 44 , 48 , 49 , 50 , 52 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 Other criteria amenable for EPC in the studies were the line of therapy or treatment 30 , 33 , 34 , 45 , 52 or resistance to a certain regime. 31 , 63 , 64 Two studies used a symptom burden over 33% regarding four symptoms, one symptom with at least 50% burden measured by the EORTC‐QLQ‐C30, 38 or cancer‐related pain higher than 3 measured by the Brief Pain Inventory, 61 to determine eligibility for the EPC intervention. An Eastern Co‐operative Oncology Group score of 0–2 was often used as an additional criterion for inclusion in the analyzed studies. 28 , 29 , 31 , 35 , 36 , 37 , 40 , 45 , 49 , 50 , 51 , 55 , 56 , 57 , 59 , 62 , 63 , 64 Findings regarding diagnoses and other inclusion criteria are summarized in Table 2 .

Studies reported different reference points to define the onset of EPC: (a) time after (advanced) cancer diagnosis, (b) estimated prognosis, and (c) other. The majority of those studies used time after diagnosis as a reference point for the onset of EPC with a time span of 8 weeks ( n = 12), 25 , 29 , 36 , 37 , 40 , 44 , 50 , 55 , 56 , 57 , 61 , 62 12 weeks ( n = 4), 25 , 43 , 58 , 59 6 weeks ( n = 2), 28 , 53 90 days ( n = 1), 27 and 16 weeks ( n = 1). 35 Estimated life expectancy was used as an (additional) reference point for the onset of EPC in nine studies: four studies used a prognosis of 6–24 months, 26 , 31 , 63 , 64 three studies an estimated life expectancy of 12 months 25 , 54 , 59 and two studies an estimated life expectancy of less than 2 months as inclusion criterion. 40 , 49

Outcome measures and elements of the intervention

The reporting of outcome measures in this review is intended to provide information on the correspondence between the described elements of EPC and the respective goals. The most common primary outcomes measured were health‐related quality of life ( n = 26), 25 , 26 , 27 , 28 , 32 , 33 , 34 , 36 , 37 , 38 , 40 , 42 , 44 , 45 , 48 , 50 , 51 , 52 , 53 , 54 , 56 , 57 , 59 , 62 , 63 , 64 symptom intensity 25 , 26 , 30 , 46 , 54 , 58 ( n = 6), resource use (e.g. treatment costs), 25 , 26 , 41 , 47 and mood 26 , 37 , 48 , 52 ( n = 4 each). Further details about the primary outcomes measured can be found in Table 3 .

Thirteen studies 25 , 26 , 31 , 32 , 36 , 40 , 41 , 46 , 50 , 52 , 59 , 61 , 63 provided more detailed information about the intervention and underlying theoretical assumptions (see Table 4 ). In this respect, three studies 26 , 46 , 49 explained the theories regarding the choice of the interventions. Two studies 46 , 63 provided a conceptual framework that captures those structural and/process elements that are conceived to contribute to the effects of EPC (so‐called active elements). 15

The assessment and management of physical ( n = 28), psychological/emotional/spiritual ( n = 27), and social ( n = 21) symptoms or needs are the most common interventions within the context of ECP. Case management or coordination of care ( n = 16), 25 , 28 , 29 , 35 , 36 , 40 , 43 , 44 , 45 , 47 , 49 , 53 , 55 , 57 , 61 , 62 goals of care/ACP/assistance with decision‐making ( n = 15), 29 , 30 , 32 , 34 , 35 , 36 , 39 , 41 , 42 , 44 , 53 , 55 , 57 , 59 , 64 illness understanding or coping ( n = 15), 33 , 34 , 37 , 39 , 40 , 42 , 44 , 46 , 50 , 51 , 52 , 53 , 55 , 57 , 59 and education ( n = 6) 25 , 26 , 31 , 46 , 54 , 61 were also often mentioned to be part of EPC in analyzed studies. Three studies provided information on resources (e.g. information leaflet for patients) to support the intervention. Eight studies 33 , 36 , 38 , 40 , 46 , 49 , 61 , 63 gave more detailed information on elements of the standard care that constituted the control intervention. 65 Table 5 summarizes the details of the elements and mode of intervention.

Professional groups and models of EPC interventions

The majority of studies provide information about the professional(s) performing the intervention ( n = 34). In most cases, a PC physician conducted the intervention alone or in a team ( n = 27) together with nurses ( n = 22) and other healthcare providers, such as social workers or psychologists. However, it was unclear whether all nurses or nurse practitioners had a PC specialization. In five studies, a PC or advanced practice nurse was solely responsible for the intervention. 26 , 32 , 53 , 58 , 59 The number or frequencies of tasks performed as part of the EPC interventions (e.g. consultations by a PC specialist per month) are reported in 38 studies. 32 studies provide data about the mode (e.g. telephone, face‐to‐face) PC specialists consulted their patients as part of the intervention. Regarding the model of implementation of EPC during the intervention period, four studies describe a consultative approach in the hospital, according to which one of the members of the PC team sees the patient and provides advice to the treating oncological team. Six studies describe an approach according to which EPC was embedded in an existing interdisciplinary team. The majority of studies ( n = 30) reported a solo practice approach in outpatient clinics, which often includes a strong coordination of care or case management approach (Table 5 ). Box 1 provides illustrations of the implementation of EPC according to the models of “consultative,” “embedded” or “solo practice.” 66

Examples of models of implementation.

The study by In Slama (2020) 52 is an example of a consultative approach in which a palliative care physician was consulted by the oncology team and visited the patient every 6–8 weeks. He assessed the physical, psychological, and social needs, coping, and need for psychosocial support. The palliative care physicians then gave recommendations for treatment to the oncologists and did not employ care plan changes themselves.

The studies of Vanbutsele (2018) 59 and Rodin (2020) 46 are examples of an embedded approach . In Vanbutsele (2018), 59 a palliative care team was introduced early in the disease trajectory and focused strongly on the assessment of physical, psychological and spiritual needs, illness understanding and medical decision‐making. The palliative care team is able to implement care plan changes and is part of the multidisciplinary case conferences. Here, the team works alongside other disciplines with their own competencies regarding decision‐making and treatment. In the study by Rodin (2020), 46 the intervention consists of psychological and physical components comprising an assessment of physical and psychological needs, education and coping strategies. While the psychological component incorporated 12 educational sessions based on cognitive behavioral therapy performed by the palliative care specialists, the physical component focused on a needs assessment two to three times a week. The usual team takes on the case up to a certain score in the needs burden assessment, while the specialist palliative care team applied symptom management over this value.

The studies of Brims (2018), 28 Temel (2010), 55 Zimmerman (2014) 63 and Zhuang (2018) 62 are examples of the solo practice . In all these studies, patients met with the clinicians in the outpatient setting, which performed physical, psychological and spiritual needs and incorporated care plans or organized further interventions performed by others. The content of the interventions then varies slightly, for example, most studies focus on the assessment and management of the aforementioned needs, while Temel (2010) 55 also incorporated goals of care planning. Some studies also had an educational component, for example, Bakitas (2009, 2015) 25 , 26 and Rodin (2020), 46 which focused on problem‐solving, symptom management, self‐care, identification and coordination of resources, communication, decision‐making and ACP. The studies also varied regarding the follow‐up mode and frequency. Brims (2018) 28 and Temel (2010) 55 have a monthly follow‐up with meetings in the outpatient clinic, while Zimmerman (2014) 63 did this via telephone without a clear schedule.

DISCUSSION

This scoping review provides an up‐to‐date comprehensive and structured analysis of existing EPC interventions in oncology. The broad range of studied cancer entities and the stage of cancer reflect the broad target group for EPC. While some elements of EPC are shared by the majority of EPC interventions (e.g. assessment of patients' symptoms), the structured analysis of the interventions shows that there are also many elements of EPC that are only used in a few studies (e.g. the implementation of ACP). The identified lack of information regarding the nature of EPC interventions as well as the lack of information about interventions in the control group make it difficult to identify those elements of EPC which most likely contribute to improvement of health of the heterogeneous group of patients with incurable cancer.

Triggers to initiate EPC in cancer care and the content of the interventions

The trigger to start EPC for most of the patients was a diagnosis of advanced or incurable cancer and/or a limited life expectancy. However, the objective and perceived health situation of patients being offered EPC seems rather heterogeneous. 67 Given that EPC directed at patients with a life expectancy of less than 6 months likely need a different care approach compared to an intervention directed at patients with a life expectancy of 2 years it seems crucial to specify the triggers as well as the content of specific EPC interventions. 68 , 69 The assessment of patients' symptoms and needs is part of most EPC interventions. Interestingly, there is little information about the role of assessment scores and possible cutoff values, which may be used to determine whether and what kind of EPC should be offered to cancer patients at all. Bearing in mind the findings of research using patient‐reported outcomes in oncology, we argue that the rigorous use of PC assessments may pave the way to more individualized EPC interventions. 14 , 70 , 71 , 72 , 73

Models of EPC and the reporting of intervention elements

Our review reveals considerable differences in how EPC is provided. EPC often had a strong case management approach, especially in the outpatient clinics. According to such model EPC not only included the assessment of symptoms but also the provision of all forms of relevant care options and coordination of different services. Such a case management approach is different from the “embedded” or “consultative” approaches (see Box 1 ). The large differences in how EPC is provided underlines the importance of a detailed description of the EPC intervention to be able to implement it on a larger scale, if successful. However, as indicated by use of the TIDieR, (see Table 4 ) information on the details of EPC interventions is currently available only for a minor part of interventions.

Clarifying core elements of EPC during different stages of incurable cancer seems also important to clarify specific professional requirements including the distinction between when to consult a generalist or specialist in PC. 66 , 68 While specialist knowledge may be worthwhile for specific symptomatic treatment, this may be less the case for basic supportive care, such as treatment of pain which is likely to be delivered as part of standard oncology care. 66

Most studies did not report in detail what has been provided as part of the control intervention. This is of particular relevance for a meaningful interpretation of findings given the fact that PC measures have been introduced at many places as part of standard care for patients with advanced and/or incurable cancer simply 65 In cases, in which patients in the control group also receive some basic PC, the effects of EPC will probably be underestimated. Knowledge about the measures in the control group is necessary to estimate the effectiveness of the EPC intervention in a real‐world clinical setting. 65 , 74

The broad range of target groups and stakeholders in ECP interventions, and the various intervention elements identified in this systematic review clearly show that EPC fulfills the characteristics of “complex interventions”. 15 Against this background, it comes as some surprise that no logic model or other theoretical account 75 , 76 seems to exist for the majority of EPC interventions. We argue that development of conceptual frameworks for particular EPC interventions may contribute to improved outcome research in terms of matching interventions and specific outcomes. In addition, we think the findings of this review and in particular the different elements of EPC, are also relevant from a clinical practice perspective. For example, it allows clinicians to stratify EPC interventions according to the goals that should be achieved for a given patients at a defined point in time in the disease trajectory. This may well differ, as EPC for some patients may be close to supportive care, while for others it may focus on advance care planning. Against this background, a more nuanced approach of EPC interventions may support the choice of which patient should be offered which type of EPC at which point in time.

Limitations

We employed a rigorous search strategy, however, some smaller studies on the topic might have been missed. Although we contacted the study authors in the case of severely missing data, we did not receive responses in all cases. Nonetheless, our results reflect the actual reporting of the studies. We searched only five databases for studies in English, Dutch and German, but there may be additional evidence in other languages as well as databases. In addition, we limited the search to specific quantitative study designs and there is additional evidence in qualitative studies on this topic. From a practice perspective, another limitation is the lack of distinction between primary and specialist palliative care interventions due to the lack of information in the included studies as well as differences in the organization of palliative care in the different countries where the studies were conducted.

CONCLUSIONS

Overall, a variety of interventions in the field of early palliative care already exist for different entities. They differ in the triggers and the mode of intervention as well as the objectives. There are clear commonalities between specific interventions. However, considerable work has to be done regarding the transparency and comprehensibility of those intervention.

AUTHOR CONTRIBUTIONS

Stephan Nadolny: Conceptualization (supporting); data curation (lead); formal analysis (equal); investigation (equal); methodology (equal); writing – original draft (lead); writing – review and editing (equal). Eva Schildmann: Formal analysis (equal); validation (equal); writing – review and editing (equal). Elena Sophie Gaßmann: Formal analysis (equal); investigation (equal); writing – review and editing (equal). Jan Schildmann: Conceptualization (lead); formal analysis (equal); methodology (equal); project administration (lead); supervision (lead); validation (equal); writing – review and editing (equal).

FUNDING INFORMATION

This research did not receive any specific grant from funding agencies in the public, commercial, or not‐for‐profit sectors.

CONFLICT OF INTEREST STATEMENT

The authors declare that they have no known conflict of interest.

Supporting information

Data S1.

Click here for additional data file.

ACKNOWLEDGEMENTS

The authors would like to thank Dr. Hilde Buiting for comments on earlier versions of this manuscript. Open Access funding enabled and organized by Projekt DEAL.

Nadolny S, Schildmann E, Gaßmann ES, Schildmann J. What is an “early palliative care” intervention? A scoping review of controlled studies in oncology. Cancer Med. 2023;12:21335‐21353. doi: 10.1002/cam4.6490

DATA AVAILABILITY STATEMENT

The data from this review can be obtained upon reasonable request to the corresponding author.

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Associated Data

Supplementary Materials

Data S1.

Click here for additional data file.

Data Availability Statement

The data from this review can be obtained upon reasonable request to the corresponding author.