Methods of Esthetic Assessment after Adjuvant Whole-Breast Radiotherapy in Breast Cancer Patients: Evaluation of the BCCT.core Software and Patients' and Physicians' Assessment from the Randomized IMRT-MC2 Trial

Evaluation of cosmetic outcomes in breast reconstruction patients undergoing radiotherapy using an anomaly generative adversarial network model

Considering the rising prevalence of breast reconstruction followed by radiotherapy (RT), evaluating the cosmetic impact of RT is crucial. Currently, there are limited tools for objectively assessing cosmetic outcomes in patients who have undergone reconstruction. Therefore, we validated the cosmetic outcome using a previously developed anomaly Generative Adversarial Network (GAN)-based model and evaluated its utility. Between January 2016 and December 2020, we collected computed tomography (CT) images from 82 breast cancer patients who underwent immediate reconstruction surgery followed by radiotherapy. Among these patients, 38 received immediate implant insertion, while 44 underwent autologous breast reconstruction. Anomaly scores (AS) were estimated using an anomaly GAN model at pre-RT, 1st follow-up, 1-year (Post-1Y) and 2-year (Post-2Y) after RT. Subsequently, the scores were analyzed in a time-series manner, considering reconstruction types (implant versus autologous), RT techniques, and the incidence of major complications. The median age of the patients was 46 years (range 29-62). The AS between Post-1Y and Post-2Y demonstrated a positive relationship (coefficient 0.515, P < 0.001). The AS was significantly associated with objective cosmetic indices, namely Breast Contour Difference (P = 0.009) and Breast Area Difference (P = 0.004), at both Post-1Y and Post-2Y. Subgroup analysis stratified by type of breast reconstruction revealed significantly higher AS values in patients who underwent prosthetic implant insertion compared to those with autologous reconstruction at all follow-up time points (1st follow-up, P = 0.001; Post-1Y, P < 0.001; and Post-2Y, P < 0.001). A threshold AS of ≥ 1.9 was associated with a 10% predicted risk of developing major complications. The feasibility of an AS generated by a GAN model for predicting both cosmetic outcomes and the likelihood of complications following RT has been successfully validated. Further investigation involving a larger patient cohort is warranted.

Expanded indications for breast-conserving surgery with oncoplastic approaches compared to conventional approaches: a single-center retrospective comparative cohort study

Background

Oncoplastic breast-conserving surgery (OPBS) is the evolution of conventional breast-conserving surgery (CBCS); however, data from studies comparing patients who received two surgical procedures are limited. A comparison of differences in terms of the patient characteristics, tumor-nipple distance, volume of resected breast tissue, tumor volume and postoperative breast appearance between patients undergoing OPBS and CBCS was carried out in this study, enhancing the evidence base for OPBS by widening indications and improving patient satisfaction.

Methods

From January 2020 to April 2022, the Breast Center of West China Hospital conducted a retrospective comparative study involving 106 patients. Preoperative characteristics of patients were recorded, and the tumor-nipple distance, the volume of resected breast tissue, tumor volume and patient-reported esthetic outcomes measured by the Harris cosmetic scale were compared between patients who underwent OPBS and CBCS.

Results

Each group had a median follow-up time of 2 months, ranging from 1 week to 6 months. The tumor-nipple distance was significantly shorter in patients receiving OPBS than in those receiving CBCS (2.98±1.42 vs. 3.85±1.78 cm, P=0.006). The rate of positive margin evaluated by intraoperative frozen section biopsy was significantly lower in OPBS group than in CBCS group (2/43, 4.65% vs. 11/63, 17.46%; P=0.048). The maximum diameter of resected tissue (7.80±2.29 vs. 6.75±1.87 cm, P=0.011) and volume of resected tissue (74.20±42.77 vs. 45.52±30.99 cm3, P<0.001) were significantly larger with OPBS. The tumor size, tumor volume (either clinically measured by ultrasound or pathologically measured), tumor location, and reoperation rate due to positive margins did not differ significantly between groups. Moreover, insignificant differences existed regarding patient satisfaction between two groups (87.30% vs. 81.40%).

Conclusions

The OPBS strategy allowed extensive resections and expanded indications with equivalent cosmetic satisfaction and favorable oncological safety.

Whole Breast Irradiation in Comparison to Endocrine Therapy in Early Stage Breast Cancer-A Direct and Network Meta-Analysis of Published Randomized Trials

BACKGROUND

Multiple randomized trials have established adjuvant endocrine therapy (ET) and whole breast irradiation (WBI) as the standard approach after breast-conserving surgery (BCS) in early-stage breast cancer. The omission of WBI has been studied in multiple trials and resulted in reduced local control with maintained survival rates and has therefore been adapted as a treatment option in selected patients in several guidelines. Omitting ET instead of WBI might also be a valuable option as both treatments have distinctly different side effect profiles. However, the clinical outcomes of BCS + ET vs. BCS + WBI have not been formally analyzed.

METHODS

We performed a systematic literature review searching for randomized trials comparing BCS + ET vs. BCS + WBI in low-risk breast cancer patients with publication dates after 2000. We excluded trials using any form of chemotherapy, regional nodal radiation and mastectomy. The meta-analysis was performed using a two-step process. First, we extracted all available published event rates and the effect sizes for overall and breast-cancer-specific survival (OS, BCSS), local (LR) and regional recurrence, disease-free survival, distant metastases-free interval, contralateral breast cancer, second cancer other than breast cancer and mastectomy-free interval as investigated endpoints and compared them in a network meta-analysis. Second, the published individual patient data from the Early Breast Cancer Trialists' Collaborative Group (EBCTCG) publications were used to allow a comparison of OS and BCSS.

RESULTS

We identified three studies, including a direct comparison of BCS + ET vs. BCS + WBI (n = 1059) and nine studies randomizing overall 7207 patients additionally to BCS only and BCS + WBI + ET resulting in a four-arm comparison. In the network analysis, LR was significantly lower in the BCS + WBI group in comparison with the BCS + ET group (HR = 0.62; CI-95%: 0.42-0.92; p = 0.019). We did not find any differences in OS (HR = 0.93; CI-95%: 0.53-1.62; p = 0.785) and BCSS (OR = 1.04; CI-95%: 0.45-2.41; p = 0.928). Further, we found a lower distant metastasis-free interval, a higher rate of contralateral breast cancer and a reduced mastectomy-free interval in the BCS + WBI-arm. Using the EBCTCG data, OS and BCSS were not significantly different between BCS + ET and BCS + WBI after 10 years (OS: OR = 0.85; CI-95%: 0.59-1.22; p = 0.369) (BCSS: OR = 0.72; CI-95%: 0.38-1.36; p = 0.305).

CONCLUSION

Evidence from direct and indirect comparison suggests that BCS + WBI might be an equivalent de-escalation strategy to BCS + ET in low-risk breast cancer. Adverse events and quality of life measures have to be further compared between these approaches.