Unlocking the Power of the Homing Phenomenon: Why Breast Conserving Surgery Outshines Mastectomy in Overall Survival

Breast cancer stands as the most frequently diagnosed malignancy in women, holding a prominent position among the leading causes of cancer-related fatalities on a global scale. Despite significant advances in treatment modalities, approximately 20% of patients experience relapses after the first 5 years of postdiagnosis surveillance. While initial investigations from the 1970s indicated comparable survival rates between breast-conserving surgery (BCS) coupled with radiation therapy and mastectomy, recent research suggests that, within the context of modern systemic and radiation therapy, BCS followed by radiation may offer an improved overall survival benefit. Nevertheless, extended follow-up studies have unveiled a notable increase in the risk of locoregional recurrence associated with breast conserving therapy in contrast to mastectomy. This article introduces a novel hypothesis rooted in the biological phenomenon of homing to elucidate this intriguing clinical observation. We postulate that a breast homing mechanism of reactivated circulating and disseminated tumor cells mediated by chemotaxis involving at least the CXCR4-SDF-1 axis may provide a biological rationale for this clinical phenomenon.

Breast Conserving Surgery in Combination With Targeted Intraoperative Radiotherapy Compared to Mastectomy for In-breast-tumor-recurrence

BACKGROUND/AIM

Mastectomy is the standard treatment of in-breast-recurrence of breast cancer after breast conserving surgery (BCS) and external beam radiation therapy (EBRT). In selected cases, it is possible to preserve the breast if targeted intraoperative radiotherapy (TARGIT-IORT) can be given during the second lumpectomy. This is a comparative analysis of overall survival and quality of life (QoL).

PATIENTS AND METHODS

Patients in our database with in-breast-recurrence and either mastectomy or BCS and TARGIT-IORT were included. Identified patients were offered participation in a prospective QoL-analysis using the BREAST-Q questionnaire. The cohorts were compared for confounding parameters, overall survival, and QoL.

RESULTS

Thirty-six patients treated for in-breast-recurrence were included, 21 had received a mastectomy and 16 patients had received BCS with TARGIT-IORT. Mean follow-up was 12.8 years since primary diagnosis and 4.2 years since recurrence. Both groups were balanced regarding prognostic parameters. Overall survival was numerically longer for BCS and TARGIT-IORT, but the numbers were too small for formal statistical analysis. No patient had further in-breast-recurrence. Psychosocial and sexual wellbeing did not differ between both groups. Physical wellbeing was significantly superior for those whose breast could be preserved (p-value=0.021). Patient-reported incidence and severity of lymphedema of the arm was significantly worse in the mastectomy group (p=0.007).

CONCLUSION

Preserving the breast by use of TARGIT-IORT was safe with no re-recurrence and no detriment to overall survival in our analysis and led to a statistically significant improvement in physical wellbeing and incidence of lymphedema. These data should increase the confidence in offering breast preservation after in-breast-recurrence of breast cancer.

Trends of Contralateral prophylactic mastectomy at the time of ipsilateral breast tumor recurrence

BACKGROUND

Contralateral prophylactic mastectomy rates have substantially increased. The study aimed to examine contralateral prophylactic mastectomy (CPM) at the time of ipsilateral breast tumor recurrence (IBTR) and evaluate factors contributing to CPM decision making process.

METHOD

Patients who developed IBTR after BCS from 2011 to 2019 were reviewed. Patient and tumor characteristics, genetic testing and reconstruction details were analyzed.

RESULTS

Ninety-six patients had IBTR after BCS and were treated with mastectomy, with 30% electing for a CPM. Patients who underwent CPM were younger, had higher BMI and less comorbidities. A genetic mutation was identified in 19% of patients who underwent testing at the time of IBTR. Tumor characteristics and performing surgeon were not predictors for CPM, however, patients were more likely to undergo CPM if they received reconstruction of the ipsilateral breast with IBTR.

CONCLUSION

This study shows that age, BMI, genetic testing and breast reconstruction are factors contributing to CPM decision at the time of IBTR.

Repeat breast-conserving treatment of ipsilateral breast cancer recurrence: a nationwide survey amongst breast surgeons and radiation oncologists in the Netherlands

Background

In line with the paradigm to minimize surgical morbidity in patients with primary breast cancer, there is increasing evidence for the safety of a repeat breast-conserving treatment (BCT) of an ipsilateral breast tumour recurrence (IBTR) in selected patients. The conditions for the feasibility of a repeat BCT vary widely in literature. In clinical practice, many physicians have ongoing concerns about the oncological safety and possible toxicity of repeat BCT.

Aim

To investigate the attitude of Dutch breast surgeons and radiation oncologists towards repeat BCT and to report on their experiences with, objections against and perceived requirements to consider a repeat BCT in case of IBTR.

Patients and methods

An online survey consisting of a maximum of 26 open and multiple-choice questions about repeat BCT for IBTR was distributed amongst Dutch breast surgeons and radiation oncologists.

Results

Forty-nine surgeons representing 49% of Dutch hospitals and 20 radiation oncologists representing 70% of Dutch radiation oncology centres responded. A repeat BCT was considered feasible in selected cases by 28.7% of breast surgeons and 55% of radiation oncologists. The most important factors to consider a repeat BCT for both groups were the patient’s preference to preserve the breast and surgical feasibility of a second lumpectomy. Arguments against a repeat BCT were based on the perceived unacceptable toxicity and cosmesis of a second course of radiotherapy. The technique of preference for re-irradiation would be partial breast irradiation (PBI) according to all radiation oncologists. Differentiating between new primary tumours (NPT) and true recurrences (TR) was reported to be done by 57.1% of breast surgeons and 60% of radiation oncologists. The most important reason to differentiate between NPT and TR was to establish prognosis and to consider whether a repeat BCT would be feasible.

Conclusion

An increasing number of Dutch breast cancer specialists is considering a repeat BCT feasible in selected cases, at the patient’s preference and with partial breast re-irradiation.

Multifocality in ipsilateral breast tumor recurrence - A study in ablative specimens

BACKGROUND

The incidence and clinical significance of multifocality in ipsilateral breast tumor recurrence (IBTR) after breast-conserving therapy (BCT) are unclear. With growing interest in repeat BCT, this information has become of importance. This study aimed to gain insight in the incidence of multifocality in IBTR, to identify patient- and tumor-related predicting factors and to investigate the prognostic significance of multifocality.

METHODS

Two hundred and fifteen patients were included in this analysis. All had an IBTR after BCT and were treated by salvage mastectomy and appropriate adjuvant therapy. Predictive tumor- and patient-related factors for multifocality in IBTR were identified using X2 test and univariate logistic regression analyses. Prognostic outcomes were calculated using Kaplan Meier analysis and compared using the log rank test.

RESULTS

Multifocality was present in 50 (22.9%) of IBTR mastectomy specimens. Axillary positivity in IBTR was significantly associated with multifocality in IBTR. Chest wall re-recurrences occurred more often after multifocal IBTR (14% versus 7% after unifocal IBTR, p = 0.120). Regional re-recurrences did not differ significantly between unifocal and multifocal IBTR (8% vs. 6%, p = 0.773). Distant metastasis after salvage surgery occurred more frequently after multifocal IBTR (15% vs. 24%, p = 0.122). Overall survival was 132 months after unifocal IBTR and 112 months after multifocal IBTR (p = 0.197).

CONCLUSION

The prevalence of multifocality in IBTR is higher than in primary breast cancer. Axillary positivity in IBTR was associated with a multifocal IBTR. Chest wall re-recurrences and distant metastasis were, although not statistically significant, more prevalent after multifocal IBTR.

Repeat breast-conserving therapy for ipsilateral breast cancer recurrence: A systematic review

The standard of care for patients with an ipsilateral breast tumour recurrence (IBTR) after breast-conserving therapy (BCT) is a salvage mastectomy. However, there is growing interest in the feasibility of repeat BCT for these patients. This systematic review contains the latest insights on BCT options for patients with an IBTR after initial BCT. A PubMed literature search was performed for articles on BCT options for IBTR after primary lumpectomy followed by radiotherapy. Weighted estimates were calculated for 5- and 10-year local control, distant metastasis-free and overall survival rates. Secondary outcomes were toxicity, cosmesis and quality of life. In total, 34 studies were eligible for analysis, of which 5 reported on repeat breast-conserving surgery (BCS) alone, 10 with mixed populations (BCS ± RT and/or mastectomy), 18 on repeat BCS followed by re-irradiation (whole-breast or partial) and one on quality of life. The weighted estimates for 5-year overall survival for repeat BCS and repeat BCS followed by reirradiation were 77% and 87%, respectively. Five-year local control was 76% for repeat BCS alone and 89% for repeat BCS followed by re-irradiation. Grade III-IV toxicity rates after re-irradiation varied from 0 to 21%, whereas the cosmesis was excellent-good in 29-100% of patients and unacceptable in 0-18%. Repeat BCS followed by re-irradiation, with either whole breast or partial breast re-irradiation, seems a feasible alternative to mastectomy in case of IBTR, in selected patients. Toxicity rates are low and the cosmetic outcome is good, but the size and follow-up of the published patient series is limited.

Dynamics of the hazard for distant metastases after ipsilateral breast tumor recurrence according to estrogen receptor status: An analysis of 2851 patients

BACKGROUND

Breast cancer (BC) patients with ipsilateral breast tumor recurrence (IBTR) are at high risk of developing distant metastases (DM). We aimed to evaluate the risk pattern of developing DM, with respect to the occurrence of IBTR, in a large series of patients homogeneously treated by conservative surgery (QUART) with a considerably long follow-up.

METHODS

Piecewise exponential model was used to investigate DM dynamics conditioning on known prognostic factors and IBTR occurrence as time dependent covariate. The model was extended to account for the timescale induced by IBTR, namely the time elapsed since IBTR to the endpoint.

RESULTS

Among 2851 BCE patients receiving QUART, 209 were assessable for IBTR. After a median follow-up of 129 months, 588 patients presented DM (CCI = 27.3%) as first event and 92 (CCI = 48.8%) following IBTR. Primary tumor size and nodal status confirmed their prognostic value. The hazard for DM was early and high in Estrogen Receptor (ER) negative BC patients; while it was initially low but increases during follow-up in ER positive cases. Patients experiencing IBTR showed DM dynamic similar to that following primary tumor, with a sudden increased risk within 24 months from surgery, regardless the time elapsed since QUART.

CONCLUSION

BC patients experiencing IBTR showed a sudden and sustained risk of DM following surgery. Our findings are consistent with the hypothesis that IBTR occurrence might act as a "time resector" for risk of DM, and provide a rationale for proper surveillance guidelines and systemic therapy for optimizing BC recurrence and appropriate choice of treatment.

Treatment outcome of ductal carcinoma in situ patients treated with postoperative radiation therapy

Purpose

To evaluate the outcome of ductal carcinoma in situ (DCIS) patients who underwent surgery followed by radiation therapy (RT).

Materials and Methods

We retrospectively reviewed 106 DCIS patients who underwent surgery followed by postoperative RT between 1994 and 2006. Ninety-four patients underwent breast-conserving surgery, and mastectomy was performed in 12 patients due to extensive DCIS. Postoperative RT was delivered to whole breast with 50.4 Gy/28 fx. Tumor bed boost was offered to 7 patients (6.6%). Patients with hormonal receptor-positive tumors were treated with hormonal therapy.

Results

The median follow-up duration was 83.4 months (range, 33.4 to 191.5 months) and the median age was 47.8 years. Ten patients (9.4%) had resection margin <1 mm and high-grade and estrogen receptor-negative tumors were observed in 39 (36.8%) and 20 (18.9%) patients, respectively. The 7-year ipsilateral breast tumor recurrence (IBTR)-free survival rate was 95.3%. Resection margin (<1 or ≥1 mm) was the significant prognostic factor for IBTR in univariate and multivariate analyses (p < 0.001 and p = 0.016, respectively).

Conclusion

Postoperative RT for DCIS can achieve favorable treatment outcome. Resection margin was the important prognostic factor for IBTR in the DCIS patients who underwent postoperative RT.

Significance of ipsilateral breast tumor recurrence after breast conserving treatment: role of surgical removal

OBJECTIVE

To analyze the pattern over time (dynamics) of further recurrence and death after ipsilateral breast tumor recurrence (IBTR) in breast cancer patients undergoing breast conserving treatment (BCT).

METHODS

A total of 338 evaluable patients experiencing IBTR were extracted from a database of 3,293 patients undergoing BCT. The hazard rates for recurrence and mortality throughout 10 years of follow-up after IBTR were assessed and were compared to the analogous estimates associated to the primary treatment.

RESULTS

In a time frame with the time origin at the surgical treatment for IBTR, the hazard rate for further recurrence displays a bimodal pattern (peaks at the second and at the sixth year). Patients receiving mastectomy for IBTR reveal recurrence and mortality dynamics similar to that of node positive (N+) patients receiving mastectomy as primary surgery, apart from the first two-three years, when IBTR patients do worse. If the patients with time to IBTR longer than 2.5 years are considered, differences disappear.

CONCLUSIONS

The recurrence and mortality dynamics following IBTR surgical removal is similar to the corresponding dynamics following primary tumor removal. In particular, patients with time to IBTR in excess of 2.5 years behave like N+ patients following primary tumor removal. Findings may be suitably explained by assuming that the surgical manoeuvre required by IBTR treatment is able to activate a sudden growing phase for tumor foci most of which, as suggested by the systemic model of breast cancer, would have reached the clinical level according to their own dynamics.