Radiotherapy in patients with distant metastatic breast cancer

Survival analysis of palliative radiotherapy in patients with HER-2+ metastatic breast cancer

Background

Whether radiotherapy can improve the long-term survival of HER-2+ metastatic breast cancer remains unclear. We launched this study to explore the effect of HER-2+ metastatic breast cancer patients through anti-HER-2 targeted therapy + radiotherapy.

Methods

488 HER-2 + metastatic breast cancer patients who received anti-HER2 targeted ± local radiotherapy from March 2006 to September 2021 were retrospectively collected. Patients were divided into a radiotherapy group (n=207) and a non-radiotherapy group (n=281) based on whether they received radiotherapy or not. 1: 1 propensity matching analysis was used to determine two groups of patients with similar baselines.

Results

Before matching, the radiotherapy group (n=207) had a median overall survival (mOS) of 51.7 months (48.8-63.8), which was superior to the non-radiotherapy group's (n=281) mOS of 33.9 months (27.9-39.9) (P < 0.0001). Moreover, the radiotherapy group exhibited better 1-year (94.6% vs 83.9%), 3-year (70.8% vs 45.5%), and 5-year (43.3% vs 25.0%) survival rates compared to the control group. Propensity score matching analysis identified 135 pairs of baseline-matched patients. In the matched groups, the mOS was 57.2 (44.5-69.8) months in the radiotherapy group (n=135) and 34.1 (27.5-40.6) months in the non-radiotherapy group (n=135), showing a statistically significant difference (P < 0.0001). Additionally, the radiotherapy group demonstrated 1-, 3-, and 5-year survival rates of 93.2%, 71.5%, and 46.9%, respectively, while those in the non-radiotherapy group were 89.4%, 45.8%, and 22.2%, respectively. Multivariate Cox analysis revealed that the presence of brain metastasis, liver metastasis, and radiotherapy were identified as independent predictive factors significantly associated with OS.

Conclusion

In patients with HER-2 positive metastatic breast cancer, radiotherapy was associated with better survival benefits compared to those who did not receive radiotherapy.

Dosimetric Comparison of Conventional Radiotherapy, Volumetric Modulated Arc Therapy, and Proton Beam Therapy for Palliation of Thoracic Spine Metastases Secondary to Breast or Prostate Cancer

The aim of this planning study was to compare the dosimetric outcomes of Volumetric Modulated Arc Therapy (VMAT), Proton Beam Therapy (PBT), and conventional External Beam Radiation Therapy (cEBRT) in the treatment of thoracic spinal metastases originating from breast or prostate cancer. Our study utilized data from 30 different treatment plans and evaluated target coverage and doses to vital organs at risk (OARs), such as the spinal cord, heart, esophagus, and lungs. The results showed that VMAT and PBT achieved superior target coverage and significantly lower doses to the spinal cord compared to cEBRT (target: median PTVD95%: 75.2 for cEBRT vs. 92.9 and 91.7 for VMAT (p < 0.001) and PBT (p < 0.001), respectively; spinal cord: median Dmax%: 105.1 for cEBRT vs. 100.4 and 103.6 for VMAT (p < 0.001) and PBT (p = 0.002), respectively). Specifically, VMAT was notable for its superior target coverage and PBT for significantly lower doses to heart, lungs, and esophagus. However, VMAT resulted in higher lung doses, indicating potential trade-offs among different techniques. The study demonstrated the relative advantages of VMAT and PBT over traditional RT in the palliative treatment of spinal metastases using conventional fractionation. These findings underscore the potential of VMAT and PBT to improve dosimetric outcomes, suggesting that they may be more suitable for certain patient groups for whom the sparing of specific OARs is especially important.

Capturing the True Cost of Breast Cancer Treatment: Molecular Subtype and Stage-Specific per-Case Activity-Based Costing

BACKGROUND

Breast cancer (BC) treatment is rapidly evolving with new and costly therapeutics. Existing costing models have a limited ability to capture current treatment costs. We used an Activity-Based Costing (ABC) method to determine a per-case cost for BC treatment by stage and molecular subtype.

METHODS

ABC was used to proportionally integrate multidisciplinary evidence-based patient and provider treatment options for BC, yielding a per-case cost for the total duration of treatment by stage and molecular subtype. Diagnostic imaging, pathology, surgery, radiation therapy, systemic therapy, inpatient, emergency, home care and palliative care costs were included.

RESULTS

BC treatment costs were higher than noted in previous studies and varied widely by molecular subtype. Cost increased exponentially with the stage of disease. The per-case cost for treatment (2023C$) for DCIS was C$ 14,505, and the mean costs for all subtypes were C$ 39,263, C$ 76,446, C$ 97,668 and C$ 370,398 for stage I, II, III and IV BC, respectively. Stage IV costs were as high as C$ 516,415 per case. When weighted by the proportion of molecular subtype in the population, case costs were C$ 31,749, C$ 66,758, C$ 111,368 and C$ 289,598 for stage I, II, III and IV BC, respectively. The magnitude of cost differential was up to 10.9 times for stage IV compared to stage I, 4.4 times for stage III compared to stage I and 35.6 times for stage IV compared to DCIS.

CONCLUSION

The cost of BC treatment is rapidly escalating with novel therapies and increasing survival, resulting in an exponential increase in treatment costs for later-stage disease. We provide real-time, case-based costing for BC treatment which will allow for the assessment of health system economic impacts and an accurate understanding of the cost-effectiveness of screening.

Unravelling oligometastatic disease from the perspective of radiation and medical oncology. Part I: non-small cell lung cancer and breast cancer

Oligometastatic disease (OMD) defines a cancer status that is intermediate between localized and widely spread metastatic disease, and can be treated with curative intent. While diagnostic imaging tools have considerably improved in recent years, unidentified micrometastases can still evade current detection techniques, allowing the disease to progress. The various OMD scenarios are mainly defined by the number of metastases, the biological and molecular tumour profiles, and the timing of the development of metastases. Increasing knowledge has contributed to the earlier and improved detection of OMD, underlining the importance of early disease control. In view of increasing OMD detection rates in current real-world clinical practice and the lack of standardized evidence-based guidelines to treat this cancer status, a board of experts from the Spanish Societies of Radiation Oncology (SEOR) and Medical Oncology (SEOM) organized a series of sessions to update the current state-of-the-art on OMD from a multidisciplinary perspective, and to discuss how results from clinical studies might translate into promising treatment options. This expert review series summarizes what is known and what it is pending clarification in the context of OMD in the scenarios of non-small cell lung cancer and breast cancer (Part I), and prostate cancer and colorectal cancer (Part II), aiming to offer specialists a pragmatic framework to help improve patient management.

A nomogram for individual prediction of vascular invasion in primary breast cancer

OBJECTIVES

To explore the feasibility of preoperative prediction of vascular invasion (VI) in breast cancer patients using nomogram based on multiparametric MRI and pathological reports.

METHODS

We retrospectively collected 200 patients with confirmed breast cancer between January 2016 and January 2018. All patients underwent MRI examinations before the surgery. VI was identified by postoperative pathology. The 200 patients were randomly divided into training (n = 100) and validation datasets (n = 100) at a ratio of 1:1. Least absolute shrinkage and selection operator (LASSO) regression was used to select predictors most associated with VI of breast cancer. A nomogram was constructed to calculate the area under the curve (AUC) of receiver operating characteristics, sensitivity, specificity, accuracy, positive prediction value (PPV) and negative prediction value (NPV). We bootstrapped the data for 2000 times without setting the random seed to obtain corrected results.

RESULTS

VI was observed in 79 patients (39.5%). LASSO selected 10 predictors associated with VI. In the training dataset, the AUC for nomogram was 0.94 (95% confidence interval [CI]: 0.89-0.99, the sensitivity was 78.9% (95%CI: 72.4%-89.1%), the specificity was 95.3% (95%CI: 89.1%-100.0%), the accuracy was 86.0% (95%CI: 82.0%-92.0%), the PPV was 95.7% (95%CI: 90.0%-100.0%), and the NPV was 77.4% (95%CI: 67.8%-87.0%). In the validation dataset, the AUC for nomogram was 0.89 (95%CI: 0.83-0.95), the sensitivity was 70.3% (95%CI: 60.7%-79.2%), the specificity was 88.9% (95%CI: 80.0%-97.1%), the accuracy was 77.0% (95%CI: 70.0%-83.0%), the PPV was 91.8% (95%CI: 85.3%-98.0%), and the NPV was 62.7% (95%CI: 51.7%-74.0%). The nomogram calibration curve shows good agreement between the predicted probability and the actual probability.

CONCLUSION

The proposed nomogram could be used to predict VI in breast cancer patients, which was helpful for clinical decision-making.

Metastasis of breast cancer cells to the bone, lung, and lymph nodes promotes resistance to ionizing radiation

BACKGROUND

Metastasis represents the leading cause of breast cancer deaths, necessitating strategies for its treatment. Although radiotherapy is employed for both primary and metastatic breast cancers, the difference in their ionizing radiation response remains incompletely understood. This study is the first to compare the radioresponse of a breast cancer cell line with its metastatic variants and report that such metastatic variants are more radioresistant.

MATERIALS AND METHODS

A luciferase expressing cell line was established from human basal-like breast adenocarcinoma MDA-MB-231 and underwent in vivo selections, whereby a cycle of inoculations into the left cardiac ventricle or the mammary fat pad of athymic nude mice, isolation of metastases to the bone, lung and lymph nodes visualized with bioluminescence imaging, and expansion of obtained cells was repeated twice or three times. The established metastatic cell lines were assessed for cell proliferation, wound healing, invasion, clonogenic survival, and apoptosis.

RESULTS

The established metastatic cell lines possessed an increased proliferative potential in vivo and were more chemotactic, invasive, and resistant to X‑ray-induced clonogenic inactivation and apoptosis in vitro.

CONCLUSION

Breast cancer metastasis to the bone, lung, and lymph nodes promotes radioresistance.

Prognostic Impact of the Tumor Marker CA 15-3 in Patients With Breast Cancer and Bone Metastases Treated With Palliative Radiotherapy

Background

The aim of the study was to explore the prognostic impact of different abnormal blood tests and the tumor marker CA 15-3 as well as established parameters such as disease extent and receptor status in patients with bone metastases from breast cancer who received palliative radiotherapy in addition to contemporary systemic treatment.

Methods

This was a retrospective uni- and multivariate analysis of 118 female patients treated in the time period from 2007 to 2014 (median follow-up 28 months).

Results

The median age was 61 years and the median time interval from the initial diagnosis of breast cancer was 57 months (median time interval from metastatic disease to radiotherapy was 7 months). Only 16% of patients had normal serum CA 15-3. HER2 receptor status correlated with CA 15-3. The median survival was 17.6 months (lowest CA 15-3 quartile), 14.7 months (intermediate), and 6.9 months (highest quartile) (P = 0.002). However, multivariate analysis showed that survival was influenced by extent of extra-skeletal metastases, pleural metastases/effusion, lung metastases, estrogen receptor status, serum C-reactive protein, and anemia with need for blood transfusion (all P < 0.05) rather than CA 15-3.

Conclusions

Survival was highly variable. The tumor marker CA 15-3 did not provide independent prognostic information. Nevertheless, the results of simple blood tests contributed to the multivariate prognostic model.

Overexpression of truncated AIF regulated by Egr1 promoter radiation-induced apoptosis on MCF-7 cells

It has been demonstrated that gene-radiotherapy can improve the radiotherapy by selectively increasing cells' response to ionizing radiation. Apoptosis-inducing factor (AIF) is a mitochondrial flavoprotein, and its C-terminal domain is responsible for the proapoptotic activity. In the present study, we overexpressed truncated AIF on MCF-7 cells by transfection of pcDNA3.1-tAIF (pc-tAIF) and pcDNA3.1-Egr1-tAIF (pc-Egr1-tAIF) plasmids. After MCF-7-tAIF cells were exposed to X-rays, the AIF and tAIF expressions, cell proliferation, apoptosis, cell cycle invasion, cytochrome c (Cyt c) release and activation of caspase-9 were measured by using Western blot, MTT assay, flow cytometry and Matrigel transwell assay, respectively. Our results showed that tAIF expression increased on time- and dose-dependent manners. Both tAIF and radiation can synergistically enhance the apoptosis, cell proliferation inhibition, cell cycle arrest and cell-invasive inhibition. In addition, tAIF overexpression and irradiation increased Cyt c release. However, only irradiation increased caspase-9 activation. Our studies indicated that tAIF overexpression might enhance apoptosis induced by radiation in MCF-7 cells.

Palliative radiotherapy with or without additional care by a multidisciplinary palliative care team in patients with newly diagnosed cancer: a retrospective matched pairs comparison

PURPOSE

To analyze survival after early palliative radiotherapy (RT) in patients managed exclusively by regular oncology staff or a multidisciplinary palliative care team (MPCT) in addition.

METHODS

Retrospective matched pairs analysis. Comparison of two groups of 29 patients each: MPCT versus none. Early RT started within three months after cancer diagnosis.

RESULTS

Bone and brain metastases were common RT targets. No significant differences in baseline characteristics were observed between both groups. Twelve patients in each group had non-small cell lung cancer. Median performance status was 2 in each group. Twenty-seven patients in each group had distant metastases. Median survival was not significantly different. In multivariate analysis, MPCT care was not associated with survival, while performance status and liver metastases were. Rate of radiotherapy during the last month of life was comparable. Only one patient in each group failed to complete radiotherapy.

CONCLUSIONS

MPCT care was not associated with survival in these two matched groups of patients. The impact of MPCT care on other relevant endpoints such as symptom control, side effects and quality of life should be investigated prospectively.