Postmastectomy radiotherapy: indications and implications

Effect of ASC Injection in the Inflammatory Reaction in Silicone Implant Capsule: Animal Model

Background

Capsular contracture is a common complication affecting about 80% of patients who receive radiotherapy after breast reconstruction with silicone prostheses. This study examines the use of adipocyte stem cells (ASCs) to treat capsular contracture.

Methods

Thirty rats were operated on to implant a minisilicone prosthesis in the dorsal region. The rats were divided into three groups: control (saline solution injection), radiotherapy (RDT), and RDT + ASC. After 3 months, the capsules were collected and submitted to histological analysis for inflammatory cell presence, vascular density, and collagen fibers, and gene expression of Tnf, Il1rap, Il10, Cd68, Mmp3, and Mmp9 by qPCR.

Results

In macroscopic analysis, the RTGO score showed a two-point reduction in RDT + ASC compared with the RDT (P = 0.003). In histological analysis, ASC exhibited less than 50% of inflammatory cells compared with RDT (P = 0.004), which was similar to control. This study demonstrated that Il1rap gene expression was identical in both RDT and RTD + ASC. Compared with control, treatment with ASC reduced Il1rap expression by 30%. Cd68 and Mmp3 expression levels were similar in both the control and RTD + ASC.

Conclusion

This study suggests that ASC treatment decreases silicone prosthesis capsule inflammation.

Effect of internal port on dose distribution in post-mastectomy radiotherapy for breast cancer patients after expander breast reconstruction

BACKGROUND

In patients with expander-based reconstruction a few dosimetric analyses detected radiation therapy dose perturbation due to the internal port of an expander, potentially leading to toxicity or loss of local control. This study aimed at adding data on this field.

MATERIALS AND METHODS

A dosimetric analysis was conducted in 30 chest wall treatment planning without and with correction for port artifact. In plans with artifact correction density was overwritten as 1 g/cm3. Medium, minimum and maximum chest wall doses were compared in the two plans. Both plans, with and without correction, were compared on an anthropomorphic phantom with a tissue expander on the chest covered by a bolus simulating the skin. Ex vivo dosimetry was carried out on the phantom and in vivo dosimetry in three patients by using film strips during one treatment fraction. Estimated doses and measured film doses were compared.

RESULTS

No significant differences emerged in the minimum, medium and maximum doses in the two plans, without and with correction for port artifacts. Ex vivo and in vivo analyses showed a good correspondence between detected and calculated doses without and with correction.

CONCLUSIONS

The port did not significantly affect dose distribution in patients who will receive post-mastectomy radiation therapy.

Safety and efficacy of immediate autologous breast reconstruction after mastectomy in patients undergoing neoadjuvant chemoradiotherapy for locally advanced breast cancer

PURPOSE

Immediate autologous breast reconstruction (IABR) offers fewer surgeries with better psychosocial, quality of life and aesthetic outcomes. In high-risk patients or those with locally advanced breast cancer (LABC), adjuvant postmastectomy radiotherapy decreases local recurrence and improves survival. However, it has negative effects on the reconstructed flap. Reversing the treatment protocol using neoadjuvant radiotherapy may minimise the negative effects on the reconstructed breast in women requesting IABR. We assessed the safety and efficacy of women who underwent mastectomy and IABR post-neoadjuvant chemoradiotherapy (NACRT) for LABC.

METHODOLOGY

A cohort study using a retrospective and prospective analysis was performed on women with LABC who underwent mastectomy and IABR post-NACRT between 1998 and 2018. All reconstructions were performed by oncoplastic breast surgeons from a single unit. Outcome measures analysed included surgical complications, flap failure, loco-regional recurrence, overall and disease-free survival. This study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). This study was approved by the institutional review board.

RESULTS

A total of 28 women with a median age of 50 (33-64) were included. 25% underwent TRAM flap and 75% underwent LD flap reconstruction. The median period of follow-up was 61 months. Post-NACRT, 35.7% achieved complete pathological response (PCR). 3/28 (10.7%) had early complications (2 implant and 1 donor site infection). 7% underwent revision surgery. There was no flap loss. 1/28 (3.5%) had loco-regional recurrence, 3.2% had distant metastasis, and 2.5% had breast cancer related mortality.

CONCLUSION

In women with LABC, NACRT followed by mastectomy and IABR is safe and may not compromise oncological and cosmetic outcomes. If offers the benefits of immediate breast reconstruction and avoids delaying adjuvant therapy.

The 2018 assisi think tank meeting on breast cancer: International expert panel white paper

We report on the second Assisi Think Tank Meeting (ATTM) on breast cancer which was held under the auspices of the European Society for RadioTherapy & Oncology (ESTRO). In discussing in-depth current evidence and practice it was designed to identify grey areas in diverse forms of the disease. It aimed at addressing uncertainties and proposing future trials to improve patient care. Before the meeting, three key topics were selected: 1) primary systemic therapy, mastectomy, breast reconstruction and post-mastectomy radiation therapy, 2) therapeutic options in ductal carcinoma in situ, and 3) therapy de-escalation in early stage breast cancer. Clinical practice in these areas was investigated by means of an online questionnaire. The time lapse period between the survey and the meeting was used to review the literature and on-going clinical trials. At the ATTM both were discussed in depth and research protocols were proposed.

Treatment Intensity Differences After Early-Stage Breast Cancer (ESBC) Diagnosis Depending on Participation in a Screening Program

BACKGROUND

While population mammographic screening identifies early-stage breast cancers (ESBCs; ductal carcinoma in situ [DCIS] and invasive disease stages 1-3A), commentaries suggest that harms from overdiagnosis and overtreatment may outweigh the benefits. Apparent benefits to patients with screen-detected cancers may be due to selection bias from exclusion of interval cancers (ICs). Treatment intensity is rarely discussed, with an assumption that all ESBCs are treated similarly. We hypothesized that women diagnosed while in a screening program would receive less-intense treatment than those never or not recently screened (NRS).

METHODS

This was a retrospective analysis of all women aged 50-69 years managed for ESBC (invasive or DCIS) during the period 2007-2013 within a single service, comparing treatment according to screening status. Data on demographics, detection, pathology, and treatment were derived from hospital, cancer registry, and screening service records.

RESULTS

Overall, 622 patients were active screeners (AS) at diagnosis (569 screen-detected and 53 ICs) and 169 patients were NRS. AS cancers were smaller (17 mm vs. 26 mm, p < 0.0001), less likely to involve nodes (26% vs. 48%, p < 0.0001), and lower grade. For invasive cancer, NRS patients were more likely to be recommended for mastectomies [35% vs. 16%; risk ratio(RR) 2.2, p < 0.0001], axillary dissection (43% vs. 19%; RR 2.3, p < 0.0001), adjuvant chemotherapy (65% vs. 37%; RR 1.7, p < 0.0001), and postmastectomy radiotherapy (58% vs. 39%; RR 1.5, p = 0.04).

CONCLUSION

Participants in population screening diagnosed with ESBC receive substantially less-intense treatment than non-participants. Differences persist when potential overdiagnosis is taken into account; these differences should be factored into debates around mammographic screening.

Postmastectomy Radiation Therapy and Two-Stage Implant-Based Breast Reconstruction: Is There a Better Time to Irradiate?

BACKGROUND

The ideal timing of postmastectomy radiation therapy (PMRT) in the setting of two-stage implant-based breast reconstruction remains unclear. In this cohort study, the authors sought to determine whether complication rates differed between patients who received PMRT following tissue expander placement (TE-XRT) and those who received PMRT after exchange for permanent implants (Implant-XRT) utilizing using prospective, multicenter data.

METHODS

Eligible patients in the Mastectomy Reconstruction Outcomes Consortium study from 11 institutions across North America were included in the analysis. All patients had at least 6-month follow-up after their last intervention (i.e., implant exchange for TE-XRT patients, and radiation for Implant-XRT patients). Complications including seroma, hematoma, infection, wound dehiscence, capsular contracture, and implant loss were recorded.

RESULTS

The authors identified a total of 150 patients who underwent immediate, two-stage implant-based breast reconstruction and received PMRT. Of these, there were TE-XRT 104 patients (69.3 percent) and 46 (30.7 percent) Implant-XRT patients. There were no differences in the incidence of any complications or complications leading to reconstructive failure between the two cohorts. After adjusting for patient characteristics and site effect, the timing of PMRT (i.e., TE-XRT versus Implant-XRT) was not a significant predictor in the development of any complication, a major complication, or reconstructive failure.

CONCLUSION

In the setting of PMRT and two-stage implant-based reconstruction, patients who received PMRT after expander placement (TE-XRT) did not have a higher incidence or increased odds of developing complications than those who received PMRT after exchange for a permanent implant (Implant-XRT).

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Survival in stage I-III breast cancer patients by surgical treatment in a publicly funded health care system

BACKGROUND

Recent investigations of breast cancer survival in the United States suggest that patients who receive mastectomy have poorer survival than those who receive breast-conserving surgery (BCS) plus radiotherapy, despite clinically established equivalence. This study investigates breast cancer survival in the publicly funded health care system present in Alberta, Canada.

PATIENTS AND METHODS

Surgically treated stage I-III breast cancer cases diagnosed in Alberta from 2002 to 2010 were included. Demographic, treatment and mortality information were collected from the Alberta Cancer Registry. Unadjusted overall and breast cancer-specific mortality was assessed using Kaplan-Meier and cumulative incidence curves, respectively. Cox proportional hazards models were used to calculate stage-specific mortality hazard estimates associated with surgical treatment received.

RESULTS

A total of 14 939 cases of breast cancer (14 633 patients) were included in this study. The unadjusted 5-year all-cause survival probabilities for patients treated with BCS plus radiotherapy, mastectomy, and BCS alone were 94% (95% CI 93% to 95%), 83% (95% CI 82% to 84%) and 74% (95% CI 70% to 78%), respectively. Stage II and III patients who received mastectomy had a higher all-cause (stage II HR = 1.36, 95% CI 1.13-1.48; stage III HR = 1.74, 95% CI 1.24-2.45) and breast cancer-specific (stage II HR = 1.39, 95% CI 1.09-1.76; stage III HR = 1.79, 95% CI 1.21-2.65) mortality hazard compared with those who received BCS plus radiotherapy, adjusting for patient and clinical characteristics. BCS alone was consistently associated with poor survival.

CONCLUSIONS

Stage II and III breast cancer patients diagnosed in Alberta, Canada, who received mastectomy had a significantly higher all-cause and breast cancer-specific mortality hazard compared with those who received BCS plus radiotherapy. We suggest greater efforts toward educating and encouraging patients to receive BCS plus radiotherapy rather than mastectomy when it is medically feasible and appropriate.