Background: Psychological distress for patients with serious illness has been associated with increased physical and spiritual distress, decreased quality of life, and increased medical expenses at end of life (EOL). For both cancer patients and their intimate partners (IPs), appraising the illness and communicating about it can be challenging. Yet, there is little evidence on how best to support them. Objectives: Bodenmann’s Systemic-Transactional Model (STM) of dyadic coping provided foundation to study how living with cancer impacts communication at primary appraisal level in patient/ IP dyad. The purpose of this exploratory multi-methods study was to understand patient/IP illness appraisals. This was investigated through following aims: 1. Describe patient/IP perceptions of dyadic communication before and after diagnosis of advanced cancer (including barriers and facilitators to sharing emotionally vulnerable content); 2. Describe patterns (incongruent/congruent) of patient and IP communication during advanced cancer; and 3. Explore relationships between experiential suffering (Suffering Pictogram) and communication congruency (CCAT-PF measure). Methods: Descriptive phenomenology was used for the qualitative phase. In-depth, semi-structured interviews with dyads were done, followed by individual interviews. The quantitative phase assessed cancer communication and suffering using established measures. Results: The main findings from qualitative analyses included: 1) Vulnerable communication is complicated by balancing two opposing worlds: Hope/Positivity and Uncertainty/Fear of Death; and 2) Vulnerable communication about EOL and hospice is emotional and unfamiliar. Hearing the word ‘hospice’ ends dyad’s uncertainty, confirming death from cancer is definite. Patients and IPs articulated feeling unprepared and needing guidance about skills to cross this vulnerable environment toward open communication. Quantitative data from communication measures showed low to medium discrepancy between dyads yet, patients displayed more discrepant communication behavior than their IP counterparts. IPs consistently exhibited higher suffering scores than patients across Overall Suffering and in 6/8 suffering domains. Worry and Fear were identified as highest domains of suffering for both patients/IPs. Conclusion: For IP dyads to articulate preferences for care with providers they must first be provided external support to facilitate vulnerable conversations within the dyad itself. These dyadic conversations must be initiated early after diagnosis to strengthen available supports during illness and EOL.