PURPOSE: A diagnosis of cancer is the start of a journey of distress and adjustment for both the patient and his/her spouse. However, the dyadic phenomena are less conceptualised and related research is in the early stages. This review explores concepts of mutuality among spousal caregiver-cancer patient dyads and identifies directions for future research. METHOD: A systematic search, including trawling through six electronic databases, a manual search, and an author search, was conducted to identity articles that had been published in English and Chinese from January 2000 to March 2013, using key terms related to caregiver-patients dyads in cancer care. An inductive content analysis approach was adopted to analyse and synthesise the concepts of spousal caregiver-cancer patient dyads. RESULTS: Thirty-one articles were identified. The findings are described according to Fletcher et al.'s proposals for conceptualising spousal caregiver-patient dyads. The proposed concepts of 'communication', 'reciprocal influence', and 'caregiver-patient congruence' have been found to be interrelated, and to contribute to the spousal caregiver-patient dyads' mutual appraisal of caregiving and role adjustment through the cancer trajectory. CONCLUSIONS: The findings highlight the importance of a perspective that focuses on the nature of the relationship between couples coping with cancer and the quality of their communication with each other. It is recognised that communication may act as a fundamental element of the abovementioned three concepts. Better communication between couples would probably facilitate reciprocal influence and caregiver-patient congruence, which in turn would have a positive effect on intimacy between the couple and improve the caregiving outcomes.