Introduction: Post-mastectomy pain syndrome (PMPS) is typically a chronic neuropathic pain, which can develop shortly after, or up to several months after surgery (BCS and MRM) and can persist for years. There is some evidence that chronic pain and sensory abnormalities do decrease over time. The study was aimed to assess frequency and intensity of chronic pain in the breast area and ipsilateral arm in already treated breast cancer patients. To study the demographic and clinical characteristics affecting the development of chronic pain and to assess the effect of chronic pain on the quality of life in post-treatment breast cancer patients. Materials and Methods: This was a cross-sectional study conducted at a tertiary institute in South India. The study included breast cancer patients older than 18 years attending the oncology clinic within the study period, who have undergone breast surgery and completed their treatments at least 6 months before and were free of disease at the time of interview. Pain characteristics were assessed in detail using the Short Form McGill Pain Questionnaire (SF-MPQ). Quality of life was assessed using the Functional Assessment of Cancer Therapy-Breast (FACT–B) questionnaire (Tamil/English version). The comparisons of domain scores were carried out by using independent student’s t test. The comparison of domain scores and overall score of FACT-B in relation to histological grade was carried out by using one-way Analysis of Variance. The association of pain with menopausal status, post-treatment duration, comorbidities, age at diagnosis, clinical stage of disease, histological grade, type of surgery, quadrant involved and postoperative complications were assessed by using χ2 test. All statistical analyses were carried out for two-tailed significance at 5% level of significance. Results: A total of seventy post-treatment breast cancer patients participated in the study. Postoperative pain was experienced by the majority of women with a VAS score of 4 to 6. The character of chronic pain was assessed using Short Form McGill Pain Questionnaire. The intensity of chronic pain was VAS 4 to 6 in 30 out of 31 patients. On comparing patients with chronic pain, there was no association noted to age, menopause, comorbidities, type of tumor, type of procedure, postoperative complication, adjuvant received and post-treatment duration. Quality of life scores in the subscales varied from 47 to 63% of their maximum scores. The mean Trial outcome index (TOI), FACT-G score and FACT-B overall score were 50%, 61% and 82% of their maximum scores respectively. On comparing women with and without chronic pain, the mean Breast Cancer Subscale (BCS) score was found to be higher and statistically significant in the latter. Though mean scores of FACT-B domains were higher in patients who underwent modified radical mastectomy, no statistically significant difference was found. On comparing quality of life scores and adjuvant therapy, it was found that all domain scores except SWB and BCS scores were significantly higher in patients who received both chemotherapy and radiotherapy than those who received radiotherapy alone. Conclusion: This preliminary work suggests that the severity of acute postoperative pain may predict future chronic pain. Aggressive treatment of acute post-operative pain may therefore decrease the incidence of chronic pain. Surgeons should be aware that younger women may be at a higher risk of developing chronic pain syndromes after breast cancer surgery. Further studies are needed to determine whether more careful surgery and radiotherapy can diminish the incidence of these symptoms.

Keywords: Chronic pain, Breast cancer, Quality of life.