The aim of the study was to examine the relationship of the Diagnostic Criteria for Psychosomatic Research (DCPR) with psychosocial variables and quality of life among cancer patients. Of 105 women with breast cancer who participated in the study, 40 (38.1%) had symptoms meeting the criteria for at least one DCPR syndrome, and 30 (28.6%) had more than one DCPR syndrome. Health anxiety, demoralization, and alexithymia were the most frequent DCPR syndromes. Patients who were diagnosed with DCPR syndromes reported higher levels of cancer-related worries and poorer quality of life than those without a DCPR diagnosis. Analysis of the single DCPR clusters and coping with cancer indicated that health anxiety was related to higher scores on the Mini-Mental Adjustment to Cancer (Mini-MAC) anxious preoccupation subscale, DCPR demoralization was related to higher scores on the Mini-MAC hopelessness subscale, and DCPR alexithymia was related to higher scores on the Mini-MAC avoidance subscale. The study indicates the usefulness of the application of the DCPR in breast cancer, although further research is needed to improve the feasibility and internal validity of DCPR constructs.