Clinical and Patient-Reported Outcomes in Women Offered Oncoplastic Breast-Conserving Surgery as an Alternative to Mastectomy: ANTHEM Multicentre Prospective Cohort Study

Medicine Oncology
oncoplastic breast-conserving surgery mastectomy patient-reported outcomes multicentre study breast cancer

Breast cancer is one of the most common cancers among women worldwide, with over 56,000 women diagnosed annually in the UK. Despite advancements in treatment, approximately 40% of patients still undergo mastectomy. While mastectomy effectively controls cancer, it profoundly impacts patients’ quality of life. Many women describe mastectomy as a “disfiguring” and “mutilating” procedure, with most preferring safe and effective alternatives.

Breast-conserving surgery (BCS) combined with radiotherapy has been proven to be an oncologically safe alternative to mastectomy. However, traditional BCS has limitations regarding tumor size and resection extent, as removing more than 10%-20% of breast tissue may lead to unacceptable cosmetic outcomes and reduced quality of life. To overcome these limitations, oncoplastic breast-conserving surgery (OPBCS) has emerged. OPBCS combines tumor resection with plastic surgical techniques, allowing for larger resections while maintaining acceptable breast morphology through volume replacement or volume displacement techniques.

Although OPBCS has theoretical advantages, there is a lack of high-quality comparative studies validating its clinical and patient-reported outcomes relative to mastectomy. Therefore, the ANTHEM multicenter prospective cohort study was conducted to explore the clinical and patient-reported outcomes of OPBCS as an alternative to mastectomy.

Source of the Paper

The study was conducted by Charlotte Davies, Leigh Johnson, Carmel Conefrey, and other researchers from several renowned institutions in the UK, including the University of Bristol and Nottingham University Hospitals NHS Trust. The findings were published in the British Journal of Surgery (BJS) in 2025, with the DOI 10.1093/bjs/znae306.

Study Process

Study Design and Participants

The ANTHEM study is a multicenter prospective cohort study aimed at comparing the clinical and patient-reported outcomes of OPBCS with mastectomy. The study recruited 362 female patients from 32 breast surgery centers in the UK, all of whom were diagnosed with primary invasive breast cancer or ductal carcinoma in situ (DCIS) and were offered OPBCS as an alternative to mastectomy.

The main inclusion criteria were: age over 18, newly diagnosed breast cancer, and being offered OPBCS as an alternative to mastectomy. Exclusion criteria included: patients not offered a choice between OPBCS and mastectomy, those requiring only simple BCS or level one oncoplastic techniques.

Data Collection and Analysis Methods

The study collected demographic, surgical, oncological, and complication data at 3 and 12 months post-surgery. Patients were asked to complete the validated Breast-Q questionnaire before surgery and at 3 and 12 months post-surgery to assess their satisfaction with breasts, psychosocial well-being, physical function, and sexual well-being.

The primary outcome measures included: the proportion of patients choosing OPBCS, the success rate of BCS, the incidence of postoperative complications, and changes in patient-reported outcomes. Data analysis used the Kruskal-Wallis test and chi-squared test to compare differences between surgical groups.

Key Findings

Patient Choices and BCS Success Rate

Of the 362 patients offered OPBCS, 294 (81.2%) chose OPBCS, with 213 opting for volume displacement techniques (therapeutic mammaplasty, TM) and 81 choosing volume replacement techniques (chest wall perforator flap, CWPF). Among the 255 OPBCS patients, 210 (82.4%) achieved clear resection margins after the initial surgery, with only 10 (3.9%) requiring mastectomy.

Postoperative Complications

The study found that patients undergoing immediate breast reconstruction (IBR) had significantly higher rates of major complications at 3 and 12 months compared to OPBCS patients. Specifically, 25% of IBR patients experienced major complications requiring readmission or reoperation at 3 months, compared to 4.9% in the OPBCS group and 0% in the mastectomy-only group.

Patient-Reported Outcomes

OPBCS patients showed significant improvements in “satisfaction with breasts” and “psychosocial well-being” scores at 3 and 12 months post-surgery, particularly in the TM group. However, OPBCS patients experienced significant declines in “physical well-being: chest” scores, especially in the CWPF group, with further declines at 12 months.

Conclusion

The ANTHEM study demonstrates that OPBCS is an effective alternative to mastectomy, allowing over 95% of patients to avoid mastectomy with lower major complication rates than immediate breast reconstruction. Notably, TM techniques showed significant advantages in improving patient satisfaction with breasts and psychosocial well-being. Therefore, OPBCS should be offered as an alternative to mastectomy for all technically feasible breast cancer patients.

Highlights of the Study

  1. High BCS Success Rate: OPBCS successfully achieved BCS in over 90% of patients, significantly reducing the need for mastectomy.
  2. Low Complication Rates: OPBCS had significantly lower major complication rates compared to immediate breast reconstruction.
  3. Improved Patient Satisfaction: OPBCS, particularly TM techniques, significantly improved patient satisfaction with breasts and psychosocial well-being.
  4. Multicenter Prospective Design: The study provided high-quality comparative data through a multicenter prospective cohort design, filling a gap in research comparing OPBCS with mastectomy.

Significance of the Study

The ANTHEM study provides crucial evidence for clinical decision-making in breast cancer surgery, supporting OPBCS as an alternative to mastectomy. The findings not only offer patients more surgical options but also provide scientific guidance for surgeons in developing personalized treatment plans. Future research should focus on the long-term effects of different surgical techniques, particularly the impact of radiotherapy on patient satisfaction and functional outcomes.

Through this study, breast cancer patients can better understand the advantages and disadvantages of different surgical options, enabling them to make choices that align with their needs and preferences.