Outcomes in real-world practice are different than cooperative trial for elderly patients with early breast cancer treated with adjuvant radiation therapy

Efficacy and safety of adjuvant therapies in older patients with breast cancer: a systematic review and meta-analysis of real-world data

BACKGROUND

Insufficient data available for older patients with breast cancer complicates decision-making regarding optimal treatment. A systematic review that uses real-world data is required for assessing the effectiveness and potential adverse effects of various therapies for this age group of patients.

METHODS

Databases of PubMed, Embase, and Cochrane Library were searched. We included clinical studies that evaluated various treatments for geriatric breast cancer, including adjuvant radiation therapy, hypofractionated radiation therapy (hypo-RT) and accelerated and partial breast irradiation (APBI), endocrine therapy, chemotherapy, and targeted therapy.

RESULTS

A total of 71 studies were retrieved. Adjuvant radiation therapy significantly improved overall survival (OS) compared with no radiation [hazard ratio (HR) = 0.60, 95% confidence interval (CI) 0.54-0.67]. The pooled estimates of OS for hypo-RT and APBI demonstrated no inferiority compared with conventional radiation. Both endocrine treatment (HR = 0.63, 95% CI 0.43-0.92) and chemotherapy (HR = 0.76, 95% CI 0.65-0.88) significantly increased OS compared with no treatment. Trastuzumab monotherapy significantly enhanced OS compared with no trastuzumab use (HR = 0.23, 95% CI 0.07-0.73).

CONCLUSION

Despite concerns about potential complications during treatment in older patients, proactive therapies significantly increase their survival rates. For patients who are frailer, hypo-RT and APBI offer survival rates comparable to traditional modalities. Additionally, targeted therapy as a monotherapy holds promise as a viable option for patients with HER2-positive breast cancer who cannot undergo chemotherapy. Therefore, by conducting thorough general assessments and clinical evaluations, the side effects of postoperative treatments can be effectively managed.

Effect of adjuvant radiotherapy after breast-conserving surgery in elder women with early-stage breast cancer: a propensity-score matching analysis

Purpose

The study aimed to explore the role of adjuvant radiotherapy (RT) after breast-conserving surgery (BCS) in elder women with early-stage breast cancer (BC).

Methods

BC patients with 70-79 years of age, stage T1-2N0-1M0, undergoing BCS were screened in the Surveillance, Epidemiology and End Results (SEER) database between 2010 and 2015. The clinicopathological characteristics were balanced with propensity-score matching (PSM) method. Kaplan-Meier curves and Cox regression analyses were performed to determine the impact of adjuvant RT on BC patients.

Results

Ultimately, 12,310 patients treated with adjuvant RT and 4837 patients treated with no RT, were involved in the analysis. Overall, patients treated with adjuvant RT was associated with a better breast cancer-specific survival (BCSS) (HR: 1.980 [1.596- 2.456], P < 0.001) and overall survival (OS) (HR: 2.214 [1.966- 2.494], P < 0.001) than those who did not undergo RT. After 1:1 PSM, adjuvant RT still performed advantage in both BCSS (HR: 1.918 [1.439- 2.557], P < 0.001) and OS (HR: 2.235 [1.904- 2.624], P < 0.001). In the multivariate COX analysis of BCSS, widowed, divorced and separated patients, tumor grade III, T2 stage, N1 stage, no RT, molecular subtypes with luminal B and triple negative were associated with a shorter BCSS (P < 0.05). In the multivariate COX analysis of OS, age ≥74 years, widowed, divorced and separated patients, tumor grade II/III, T2 stage, no RT, no chemotherapy, molecular subtypes with triple negative were associated with a shorter OS (P < 0.05). Furthermore, the advantages of adjuvant RT were observed in all subgroup analysis.

Conclusion

Adjuvant RT after BCS can improve both BCSS and OS in elderly patients with early-stage BC. Additionally, all subgroups analysis-derived BCSS and OS were in support of RT.

Radiation and/or endocrine therapy? Recurrence and survival outcomes in women over 70 with early breast cancer after breast-conserving surgery

PURPOSE

Women over 70 with early breast cancer treated with breast-conserving surgery are typically offered adjuvant endocrine and radiation therapy. Prior studies have supported the omission of adjuvant radiation in this low-risk population. We sought to compare the effect of adjuvant treatment with endocrine therapy alone, radiation therapy alone or both versus no adjuvant treatment on local control and survival in this population.

METHODS

Data were extracted on 1363 breast cancer patients over the age of 70 treated with a breast-conserving surgery from 2003 until 2018. 460 patients met inclusion criteria of pT1N0, invasive disease with negative margins and not treated with chemotherapy. The primary outcome of this population-based study was local recurrence-free survival at 5 and 10 years.

RESULTS

Patients receiving no adjuvant therapy had worse local recurrence-free, loco-regional recurrence-free and disease-free survival than patients receiving at least one form of adjuvant therapy (p < 0.05). 5-year local recurrence rates were 0.8% in patients receiving both endocrine and radiation therapy, 1.5% in those receiving radiation alone, 4.2% in those receiving endocrine therapy alone and 12% in those receiving no adjuvant therapy.

CONCLUSIONS

This study supports the benefit of some form of adjuvant therapy (radiation alone, endocrine therapy alone or both) in low-risk breast cancer patients over 70. Receiving no adjuvant therapy is associated with poorer outcomes. Many of these patients are candidates for Accelerated Partial Breast Irradiation which can be completed in less than a week. These patients should be offered radiation therapy, endocrine therapy or both.

Accelerated partial breast irradiation in the elderly: 5-Year results of the single fraction elderly breast irradiation (SiFEBI) phase I/II trial

PURPOSE

To evaluate the clinical outcomes of a very-accelerated partial breast irradiation (vAPBI) in the elderly based on a single fraction of multicatheter interstitial high-dose rate brachytherapy (MIB). Mature results with a median follow-up of 5 years.

METHODS AND MATERIALS

From November 2012 to September 2014, 26 patients (pts) (≥70) with early breast cancer were enrolled in a prospective phase II trial (NCT01727011). After lumpectomy, intraoperative catheter implant was performed for postoperative APBI (single fraction 16 Gy). Surveillance was performed twice a year after APBI. Oncologic outcome (local [LRFS], metastasis-free survival, cancer-specific survival, and overall survival [OS]) as well as late toxicity and cosmetic outcome were investigated.

RESULTS

Median age was 77 years [69-89]. After a median follow-up of 63 months [60-68], 5-year LRFS, metastasis-free survival, cancer-specific survival, and overall survival rates were 100%, 95.5%, 100%, and 88.5%, respectively. Late toxicity was observed in 5 pts (19.2%) with a total of five events: 3 pts G1 (60%); and 2 pts G2 (40%). The observed late side effects were breast pain in 1 pt (G2 cytosteatonecrosis with occasional acetaminophen consumption), hypopigmentation (puncture site) in 2 pts (G1) and breast fibrosis in 2 pts (G1: 1 pt; G2: 1 pt). Cosmetic evaluation was excellent for 21 pts (81%) and good for 2 pts (19%).

CONCLUSION

For elderly with early breast cancer, a vAPBI using a single fraction of postoperative MIB (16 Gy) provides excellent oncologic results, mainly in terms of local control and cancer death. Late toxicity and cosmetic profile are acceptable.

Radiation Therapy After Breast-Conserving Surgery in Women 70 Years of Age and Older: How Wisely Do We Choose?

BACKGROUND

Despite data from randomized trials supporting omission of radiation therapy (RT) for women ≥ 70 years of age with T1, estrogen receptor-positive (ER+) tumors undergoing breast-conserving therapy (BCT), RT usage remains high. We reviewed our institutional experience to determine if risk factors for local recurrence or comorbidities influenced use.

METHODS

Women ≥ 70 years of age with T1, ER+, human epidermal growth factor receptor 2-negative (HER2-) tumors undergoing BCT in 2010-2012 were identified from a prospectively maintained database. Ten-year estimated mortality was calculated using the Suemoto index. The associations of clinicopathological features and mortality risk on receipt of RT were examined.

RESULTS

Overall, 323 patients with 327 cancers were identified. Median age was 75 years, median tumor size was 1 cm, and all were clinically node negative; 53.7% of patients received RT. RT usage decreased with age (73.6%, age 70-74 years; 49.5%, age 75-79 years; 33.3%, age 80-84 years; 10.7%, ≥ 85 years; p < 0.001). Within age groups, estimated mortality did not impact RT usage. On multivariable analysis, only younger age and larger tumor size were associated with RT use. Recurrence-free survival was 98% versus 93% with and without RT, respectively (p = 0.011). Those who received adjuvant radiation also had improved overall survival (92% vs. 89%), although this effect did not reach statistical significance (p = 0.051).

CONCLUSION

Neither the factors associated with risk of local recurrence nor the estimated risk of death in 10 years were associated with use of adjuvant radiation in a large cohort of women ≥ 70 years of age with small ER+ breast cancers treated with breast-conserving surgery.