AIM: The aim of the present study was to evaluate quality of life (QL) over time in patients undergoing breast-conserving surgery, due to primary operable breast cancer, in Greece.MATERIALS AND METHODS: This was a prospective, questionnaire-based study in women with primary operable breast cancer. A Greek version of the Functional Assessment of Cancer Therapy-Breast (FACT-B) questionnaire was used. Patients filled out all six subscales of FACT-B, initially 24 h prior to and then 3-7 days and 9-12 months after breast-conserving surgery. All participants received standard adjuvant therapy. Patients with metastatic disease, psychiatric comorbidities and those treated with neoadjuvant therapy were excluded. Data were statistically analyzed using parametric and nonparametric tests as indicated.RESULTS: In total, 155 women, with a mean age of 59.2 years (range 30-80 years), filled out the study questionnaire. Patients' social/family well-being improved 3-7 days and 9-12 months after the operation as compared with the preoperative period (p < 0.05). Patient-doctor relationship and functional well-being deteriorated (p < 0.05), while physical well-being improved (p < 0.05) 9-12 months after surgery than prior to or 3-7 days postoperatively. Finally, emotional well-being and "additional concerns" and overall QL were all better 3-7 days postoperatively than prior to or 9-12 months after the operation (p < 0.05). Among demographic factors, patient age and place of residence did not appear to have any effect on QL, in contrast to marital status, with married women having better QL in the social/family subscale (p < 0.05). With respect to histopathological factors, patients with ER- and/or PR-positive tumors had better QL in the physical well-being but worse in the functional subscale, 9-12 months after surgery. No significant correlation was found between QL and other histopathological factors.CONCLUSION: In the long term, patients' QL deteriorates with respect to functional and emotional well-being, "additional concerns" and patient-doctor relationship. Hence, specific interventions should aim to improve these aspects of QL in breast cancer patients undergoing breast-conserving surgery.