The review followed the Joanna Briggs Institute method for scoping reviews [24] and was reported by the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) checklist [25]. We preregistered the scoping review protocol on the Open Science Framework (registration number: 29YA3) [26].

The primary objective of this scoping review is to map and summarize the evidence on the effects of psychological interventions designed to reduce FCR in people with cancer.

The scoping review addressed the following questions:

We used the population/participant-concept-context framework [24] to define eligibility.

We included any quantitative study design that reported data relevant to the research questions, including randomized controlled trials (RCTs), quasi-experimental studies, nonrandomized intervention studies, observational studies, and mixed methods studies with extractable intervention data. Review articles were excluded to avoid data duplication, but the reference lists were screened for relevant studies. We also excluded ongoing trials and protocol papers.

The search strategy was initially focused on colorectal cancer, but due to an insufficient number of studies, it was broadened to include all people with cancer. The search strategy was developed based on three key concepts: (1) neoplasms, including synonyms such as neoplas*, cancer, carcinom*, malignant*, tumor*, and oncolog*; (2) fear, with related terms including anxiety, worr*, concern, and distress; and (3) recurrence, with associated terms such as relapse, progress*, reappearance, and return. These terms were combined using the Boolean operator “OR” within each concept group and “AND” between the concept groups. However, the “fear” and “recurrence” concepts were combined using a proximity operator (adj4) in most databases to ensure co-occurrence within a 4-word context. The research team designed the search strategy in collaboration with an experienced librarian, and it was adapted for each database. We searched the reference lists of all studies included in the review to identify additional studies.

We searched 5 electronic databases: CINAHL, PsycInfo, the Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and MEDLINE. To capture relevant gray literature, we also searched 2 gray literature sources: ProQuest Dissertations & Theses Global and the World Health Organization International Clinical Trials Registry Platform. These sources were searched from January 1980 to April 2024, given that the concept of FCR was initially raised in the early 1980s [1]. The detailed search strategy and results are provided in Table S1 in Multimedia Appendix 1. We imported the search results from all databases into Covidence [27] and removed duplicates.

Two authors (NL and TOL) screened titles and abstracts independently for assessment against the inclusion criteria. A third author (CW) resolved any disagreements. A flowchart was created to standardize article selection decisions between screeners (Figure S1 in Multimedia Appendix 1). Two independent reviewers (NL and CW) assessed the full texts in detail against the inclusion criteria. Any disagreements between the reviewers were resolved through discussion with a third author (LR). Reasons for exclusion at the full-text stage were recorded and are presented in the PRISMA-ScR flow diagram (see the Results section).

We piloted the data extraction form on the first 5 eligible studies and modified it accordingly. A data dictionary was developed with collective input from the author team to specify all elements of the data extraction form (Table S2 in Multimedia Appendix 1). One reviewer (NL) then extracted the data in Microsoft Excel under the supervision of the research team to ensure adherence to the predefined extraction protocol. The extracted data included:

Given the heterogeneity across included studies, we conducted a descriptive analysis approach to synthesize the findings. Descriptive numerical summaries were presented through tables and figures to map the characteristics of the included studies, and the findings were synthesized narratively [28]. The synthesis was structured around the review questions.

We summarized the characteristics of the identified studies by reporting frequencies and percentages. We also extracted how FCR was defined and which measurement tools were used in each study and grouped these definitions and measures into tables separately. Key intervention content (ie, components, sample sizes, measurement tools, study design, and reported statistical significance) was summarized. To clearly present the diverse intervention approaches for reducing FCR, we classified the interventions according to their theoretical basis (including blended interventions, cognitive behavioral therapy [CBT], mindfulness-based intervention [MBI], acceptance and commitment therapy [ACT], tailored psychoeducational interventions, and others) with categories developed inductively from the included studies. We created a harvest plot to visually present the distribution of interventions across cancer types and study designs.

We identified 8128 citations through database searches and 242 additional records from gray literature and reference tracking. After removing duplicates, 5131 titles and abstracts were screened, with 4935 excluded. We assessed the full texts of the remaining 196 articles and excluded 74 of them. A total of 122 studies were included in the review (Figure 1).

Sixty-five (53.3%) studies were published within the last 5 years (Table 1). The United States accounted for the highest number of studies (n=35, 28.7%). Forty-eight (39.3%) studies focus on breast cancer, followed by 47 (38.5%) studies that included participants with more than one cancer type. The majority of studies (n=64, 52.5%) were RCTs.

The interventions were categorized according to their theoretical basis (Table 1). Blended interventions (different combinations of CBT, mindfulness, ACT, and other strategies) formed the largest category (n=38, 31.1%), followed by CBT (n=26, 21.3%) and MBIs (n=24, 19.7%). All studies implemented interventions post diagnosis (Table S3 in Multimedia Appendix 1). In 38 (31.1%) studies, researchers did not report the exact clinical timepoint of intervention delivery. Thirty-six (29.5%) trials included “people who had completed or were still undergoing cancer treatment.” The remaining 48 (39.3%) targeted “people who were disease-free,” with the timing of intervention delivery ranging from 3 months to 15 years following primary cancer treatment. Most interventions were delivered by disciplinary specialists (n=117, 95.9%), with psychologists being the most common providers (n=68, 55.8%).

Only 28 (23%) studies identified which FCR definition they used. Among them, 9 (32.1%) studies used Vickberg’s definition [28-36], 18 (64.3%) studies used Lebel et al definition [37-54], and 1 (3.6%) study [55] cited the FCR definition by Herschbach and Dinkel [56]. These three definitions are summarized in Table 2. Vickberg’s [57] definition, developed for breast cancer patients, describes FCR as the fear that cancer may return either in the same location or in another part of the body. Lebel et al [2] proposed a definition based on a Delphi consensus process, defining FCR as “fear, worry, or concern relating to the possibility that cancer will come back or progress.” Herschbach and Dinkel [56] introduced the concept of fear of progression (FoP), which specifically highlights concerns about disease progression and its associated psychosocial consequences.

Eighteen validated measurement tools were identified (Table S4 in Multimedia Appendix 1). Thirteen (72.2%) were specifically designed to assess FCR/FoP, while the remaining 5 (27.8%) included FCR-related items as part of broader assessments. The Fear of Cancer Recurrence Inventory [58] was the most frequently used tool, appearing in 40 (31.7%) studies. Other commonly used tools included the Concerns About Recurrence Scale [57], used in 20 (15.9%) studies, and the Fear of Cancer Recurrence Inventory-Short Form [59], used in 18 (14.3%) studies.

This scoping review is the first to map all psychological intervention strategies for alleviating FCR across cancer types and to identify key gaps in existing evidence. From our review, only about one-fifth of the studies reported the definition of FCR used. Eighteen validated FCR measurement tools were identified. Blended interventions, CBT, and MBIs were the most common approaches, typically delivered face-to-face by disciplinary specialists. Breast cancer populations dominated the evidence base, while other cancer types received limited attention. Most interventions reported statistically significant effects in reducing FCR, although the wide variation in study designs, intervention components, outcome measures, and follow-up durations makes meaningful interpretation difficult.

A clear definition of FCR is critically important, as it underpins the identification of its clinical manifestations, supports accurate diagnosis in clinical settings, and informs the design of targeted interventions that address the specific fears and cognitive patterns associated with cancer recurrence [21,32]. Much of the existing literature treats the definitions of FCR and FoP interchangeably [159,160]. However, Coutts-Bain et al [161] conducted a factor analysis and found that, although FCR and FoP are related, they are structurally distinct psychological constructs. It challenges the previous assumption that the two are the same construct and emphasizes the importance of clearly distinguishing between FCR and FoP in clinical practice and research. Conceptually, FCR is more relevant to cancer survivors who have completed curative treatment and are in remission, encompassing concerns about the cancer returning after a period of being disease-free. In contrast, individuals with metastatic cancer are less likely to fear recurrence and more likely to experience fear of progression, worrying about the cancer worsening or spreading further due to the ongoing nature of their illness [162]. Consequently, clearly distinguishing between FCR and FoP in clinical practice and research not only facilitates the development of more effective, targeted interventions but also enhances the accuracy of research findings and enables the provision of more tailored psychological support to cancer survivors.

Blended interventions were the most commonly investigated for reducing FCR among cancer survivors, with numerous studies reporting positive outcomes. This finding aligns with another review of 13 studies [163], which also identified that interventions combining CBT and MBI strategies were effective in reducing FCR. In recent years, researchers have proposed that traditional CBT may have limitations in managing FCR, particularly among survivors living with ongoing uncertainty [21,164]. An overemphasis on challenging “irrational” thoughts may leave some people feeling misunderstood or emotionally invalidated, especially when their fears are grounded in real risk rather than cognitive distortion [165]. However, evidence supporting these concerns remains limited. Some scholars regard ACT as a contextual extension of CBT, incorporating core mindfulness-based practices to enhance individuals’ awareness and acceptance of their emotions [166]. Similarly, mindfulness techniques are increasingly integrated into traditional CBT. A prime example of this integration is mindfulness-based cognitive therapy, which combines the cognitive restructuring techniques of CBT with mindfulness practices to help individuals break the cycle of negative thinking and reduce the FCR [121].

The diversity in FCR interventions reflects the lack of a universally agreed theoretical foundation and the variety of disciplinary approaches to understanding cancer-related psychological experiences, which creates challenges for their application in clinical practice. Despite growing research on FCR interventions, cancer survivors still rarely receive support for managing FCR outside the research environment [167]. It is therefore important to identify the core effective components across FCR interventions and to examine whether tailored approaches for specific cancer populations offer advantages over more general interventions [168]. Furthermore, for widespread adoption, considerations such as cost-effectiveness and resource requirements will be essential to ensure the feasibility of dissemination [169,170].

The majority of existing FCR interventions were resource-intensive, requiring in-person delivery over multiple sessions by trained specialists. These findings are also supported by a previous review by Pradhan et al [122]. As FCR is a persistent and commonly unmet concern across cancer survivor populations, there is a pressing need for scalable solutions [47,164]. In addition, a recently published consensus statement [165] indicates that approximately 80% of cancer survivors do not require high-intensity therapy, and that lower-intensity approaches, such as self-guided online programs, psychoeducational resources, or brief interventions delivered via SMS text messages or telephone, can reduce FCR [165]. In this context, mobile health interventions offer greater scalability and accessibility with reduced demands on health care resources, making them a promising alternative [171]; text messaging–based programs have shown positive outcomes in the management of mental health disorders [172] and in improving self-management of chronic conditions [173]. However, there remains a lack of mobile health programs in managing FCR.

In this review, the majority of studies (85%) reported statistically significant effects of interventions on FCR. This trend is consistent with evidence from previous systematic reviews and meta-analyses, which also demonstrated small-to-moderate reductions in FCR across specific psychological interventions [164,174]. However, this predominance of positive findings may be partially explained by publication bias, whereby studies with null or negative results are less likely to be published [175]. Researchers and journals often favor significant or “positive” outcomes, which can distort the evidence base and lead to an overestimation of intervention effectiveness [176]. Selective outcome reporting may further contribute to this bias, as authors might emphasize significant results while downplaying or omitting nonsignificant findings [177]. Small sample sizes in some studies may increase the risk of false positives and inflated effect sizes [178]. Collectively, these factors could mislead clinical decision-making and contribute to the adoption of interventions with uncertain or limited effects. In addition, while most interventions reduced FCR, these findings should be interpreted with caution due to the heterogeneity across the included studies. The interventions varied widely in terms of dose, delivery format, sample size, measurement time points, and study design, all of which pose significant challenges for synthesizing the findings. Such variability limits the comparability of studies and makes it difficult to have a specific conclusion regarding the overall effect of interventions for managing FCR. These challenges are inherent to scoping reviews, which aim to map diverse and broad evidence [28,179]. It is necessary to conduct a systematic review with high-quality RCTs to evaluate the effectiveness of different interventions in the future.

Although FCR was recognized as a clinical concern in the 1980s [1], our review found that interventions only began to appear from around 2009. FCR was underrecognized as a distinct psychological construct and was often assessed as part of broader measures of distress, anxiety, or quality of life previously [7]. The lack of validated tools specifically designed to assess FCR also limited early research and hindered the earlier evaluation of intervention outcomes [58]. Over the past two decades, the growing number of cancer survivors has shifted the focus of cancer care from survival alone to long-term psychological well-being, highlighting the need for FCR-specific interventions [2].

First, this review used a vote-counting approach to summarize intervention effects because of the heterogeneity across studies. However, this means all studies were weighted equally, regardless of their quality, sample size, or effect size, which limits our ability to compare effect estimates or assess the clinical meaningfulness of intervention outcomes. In addition, we did not conduct a quality appraisal of the included studies, consistent with the methodological nature of a scoping review. Future research would benefit from high-quality systematic reviews and meta-analyses that incorporate rigorous risk-of-bias assessments and enable quantitative comparisons of the effectiveness of different intervention modalities.

Second, this review was limited to English-language articles or English-language abstracts, and the exclusion of non-English publications may have reduced the completeness and representativeness of the evidence. This restriction may introduce language bias and underrepresent studies conducted in non-English-speaking regions. Nonetheless, our review included studies from 5 continents, indicating some geographic diversity despite the language limitation. Future reviews should consider removing language restrictions to ensure broader inclusion.

Third, this review relied solely on published information and did not seek additional details from study authors, which may have resulted in incomplete reporting of methodological or contextual elements, such as the specific definitions of FCR used. Future studies would benefit from more detailed reporting and from contacting authors when necessary to obtain missing information.

Our scoping review mapped the full range of psychological intervention strategies aimed at alleviating FCR across cancer types. We identified 122 studies encompassing diverse FCR interventions. FCR has been the focus of an increasing number of studies since 2009, with the majority being RCTs. Most interventions are delivered face-to-face and rely on trained specialists, limiting their scalability and accessibility. Most have had statistically significant results. However, the included studies demonstrated heterogeneity in terms of delivery, duration, and dose, requiring cautious interpretation of intervention effects. Future research should develop consistent guidelines to standardize the definition of FCR, the measurement tools used, and the timing of follow-up assessments, thereby improving comparability across studies and strengthening the evidence base. Long-term follow-up data are needed to evaluate the sustained effects. As most studies have focused on breast cancer survivors, further research is needed to provide evidence for other cancer populations.