Professionally led support groups for people living with advanced or metastatic cancer: a systematic scoping review of effectiveness and factors critical to implementation success within real-world healthcare and community settings.

Purpose: To examine the effectiveness of professionally led support groups for people with advanced or metastatic cancer, and identify factors critical to implementation success within real-world settings.

Methods: Databases (MEDLINE; PsychINFO; CINAHL) and grey literature were searched for empirical publications and evaluations. Articles were screened for eligibility and data systematically extracted, charted and summarised using a modified scoping review methodology. Implementation factors were mapped using Proctor's implementation framework and the Consolidated Framework for Implementation Research 2.0.

Results: A total of 1691 publications were identified; 19 were eligible for inclusion (8 randomised controlled trials, 7 qualitative studies, 2 cohort studies, 2 mixed methods studies). Most (n=18) studies focused on tumour-specific support groups. Evidence supported professionally led support groups in reducing mood disturbances (n=5), distress (i.e. traumatic stress, depression) (n=4) and pain (n=2). Other benefits included social connectedness (n=6), addressing existential distress (n=5), information and knowledge (n=6), empowerment and sense of control (n=2), relationships with families (n=2) and communication with health professionals (n=2). Thirteen studies identified factors predicting successful adoption, implementation or sustainment, including acceptability (n=12; 63%), feasibility (n=6; 32%) and appropriateness (n=1; 5%). Key determinants of successful implementation included group leaders' skills/experience, mode of operation, travelling distance, group composition and membership and resourcing.

Conclusions: Professionally led tumour-specific support groups demonstrate effectiveness in reducing mood disturbances, distress and pain among patients. Successful implementation hinges on factors such as leadership expertise, operational methods and resource allocation.

Implications for cancer survivors: Professionally led support groups may fill an important gap in supportive care for people with advanced or metastatic cancer.