Primary brain tumors (PBTs) are rare but have a great impact on both patient and family caregiver wellbeing. Supporting caregivers can help them to continue their caregiving activities to maintain the patients’ best possible level of quality of life. Efforts to improve PBT caregiver wellbeing should take into account country- or culture-specific differences in care issues and supportive care needs to serve larger caregiver groups. We aimed to explore PBT caregivers’ satisfaction with the current supportive care provision, as well as their thoughts on monitoring their care issues with both paper-based and digital instruments. Twelve PBT caregivers were interviewed in the United States. The semi-structured interviews were transcribed verbatim and analyzed by two coders independently. Data were combined with those collected in the Netherlands, following similar methodology (N = 15). We found that PBT caregivers utilize both formal and informal support services, but that those who experience more care issues would prefer more support, particularly in the early disease phase. Keeping track of care issues was thought to provide more insight into unmet needs and help them find professional help, but it requires investment of time and takes discipline. Caregivers preferred a brief and easy-to-use ‘blended care’ instrument that combines digital monitoring with personal feedback. The present study shows that the preferences of family caregivers in neuro-oncology toward keeping track of care issues are likely not heavily influenced by country- or culture-specific differences. The development of any instrument thus has the potential to benefit a large group of family caregivers.