Pathologic complete response of ductal carcinoma in situ to neoadjuvant systemic therapy in HER2-positive invasive breast cancer patients: a nationwide analysis.

PURPOSE: Ductal carcinoma in situ (DCIS) is present in more than half of HER2-positive invasive breast cancer (IBC). Recent studies show that DCIS accompanying HER2-positive IBC can be completely eradicated by neoadjuvant systemic therapy (NST). Our aim was to determine the percentage of pathologic complete response of the DCIS component in a nationwide cohort and to assess associated clinicopathologic variables. Furthermore, the impact on surgical treatment after NST was investigated. METHODS: Women diagnosed with HER2-positive IBC, treated with NST and surgery, between 2010 and 2020, were selected from the Netherlands Cancer Registry. Pre-NST biopsy and postoperative pathology reports were obtained from the Dutch Nationwide Pathology Databank and assessed for the presence of DCIS. Clinicopathologic factors associated with DCIS response were assessed using logistic regression analyses. RESULTS: A DCIS component was present in the pre-NST biopsy in 1403 (25.1%) of 5598 included patients. Pathologic complete response of the DCIS component was achieved in 730 patients (52.0%). Complete response of DCIS occurred more frequently in case of complete response of IBC (63.4% versus 33.8%, p < 0.001). ER-negative IBC (OR 1.79; 95%CI 1.33-2.42) and more recent years of diagnosis (2014-2016 OR 1.60; 95%CI 1.17-2.19, 2017-2019 OR 1.76; 95%CI 1.34-2.34) were associated with DCIS response. Mastectomy rates were higher in IBC+DCIS compared to IBC (53.6% versus 41.0%, p < 0.001). CONCLUSION: Pathologic complete response of DCIS occurred in 52.0% of HER2-positive IBC patients and was associated with ER-negative IBC and more recent years of diagnosis. Future studies should investigate imaging evaluation of DCIS response to improve surgical decision making.

Breast-related and body-related quality of life following autologous breast reconstruction is superior to implant-based breast reconstruction - A long-term follow-up study.

INTRODUCTION: The better survival rates after breast cancer allow for setting of long-term goals, such as Quality of Life (QoL) and aesthetic outcomes following breast reconstruction. Studies find a higher breast-related QoL and greater satisfaction with breasts following autologous breast reconstruction (ABR) compared to implant-based breast reconstruction (IBR). However, aesthetic results from donor sites can influence body image. This concern is little addressed in the literature. Therefore, the aim of this study was to compare the long-term breast-related and body-related QoL of women who underwent ABR to women who underwent IBR. MATERIAL AND METHODS: A multicenter, cross-sectional survey was conducted between November and December 2020 among women who underwent postmastectomy breast reconstruction between January 2015 and December 2018. A general questionnaire, the BREAST-Q, and the BODY-Q were used to collect data. Multivariable linear regression was performed to adjust differences in Q-scores for potential confounders. RESULTS: In total, 336 patients were included (112 IBR, 224 ABR). Autologous reconstruction resulted in significantly higher mean scores in all subdomains of the BREAST-Q. On the BODY-Q, IBR scored significantly higher on scars, while ABR scored moderately to significantly higher on all other scales. Despite a lower mean score on Hips & outer thighs in women with Lateral Thigh Perforator (LTP) flap reconstruction, no negative influence on body image was found in these women. CONCLUSIONS: Long-term breast-related and body-related outcomes of ABR are superior to IBR. Donor site aesthetic does not adversely affect body image in women who underwent free flap breast reconstruction.