Spiritual Well-Being as a Patient-Reported Assessment Dimension in Advanced Cancer: Clinical Validation and Quality-of-Life Implications

Background: In advanced cancer care, routine clinical assessment often focuses on symptoms, treatment tolerance, and disease status, while spiritual well-being remains insufficiently explored despite its relevance to quality of life (QoL). Standardized patient-reported tools may help identify spiritual and existential vulnerability in patients receiving palliative treatment. This study evaluated the EORTC QLQ-SWB32 as a structured spiritual well-being assessment tool in advanced cancer care through its cultural adaptation and clinical validation among Romanian patients. Furthermore, it evaluated the tool’s feasibility and explored the association between spiritual well-being and QoL in individuals receiving palliative systemic therapy. Methods: Following EORTC Quality of Life Group guidelines, the QLQ-SWB32 was translated and pilot-tested with ten cancer patients. A prospective, cross-sectional observational study was then conducted at the Regional Institute of Oncology in Iași, Romania. Over six months, 42 adult patients with metastatic or locally advanced inoperable malignancies undergoing palliative systemic therapy were enrolled. Participants completed the EORTC QLQ-SWB32 and EORTC QLQ-C15-PAL questionnaires, while sociodemographic and clinical variables were collected using structured case report forms. Results: The translated instrument showed good linguistic clarity and clinical acceptability during pilot testing. The study cohort was predominantly aged 40–64 years (52.38%) and was socio-culturally homogeneous, with all patients identifying as Romanian and most as Eastern Orthodox (92.85%). The Relationship with God/the Divine (RSG) domain showed a stronger association with QoL in male patients than in female patients, particularly in subsequent treatment lines. In the subsequent-line subgroup, residential environment reached statistical significance (p = 0.021), with a stronger RSG–QoL correlation among rural residents. Age-related inversion patterns in the RSG–QoL association were also observed across treatment lines. Conclusions: Spiritual well-being assessment may provide clinically relevant patient-reported information in advanced cancer care. The Romanian EORTC QLQ-SWB32 demonstrated feasibility, linguistic clarity, and clinical validity as a structured assessment tool. The association between the Relationship with God/the Divine domain and QoL varied according to sex, age, residential environment, and treatment trajectory, supporting the integration of standardized spiritual assessment into individualized palliative oncology care.