Nomogram for the personalisation of radiotherapy treatments in breast cancer patients

Introduction

Numerous prospective studies have shown that the incorporation of genomic assays into clinical practice significantly impacts the choice of adjuvant treatments for patients with early-stage breast cancer. However, the same evidence does not exist for the treatment of locoregional recurrences.

Hypothesis and objectives

The main objective of this work was to identify the clinicopathological, molecular, and genetic parameters that allow patients to be more precisely categorised into risk groups, in order to create a locoregional recurrence riskclassification tool, the PersonalRT27.

Material and methods

To create PersonalRT27, we retrospective assessed the variables of patients with early breast cancer (stages I or II) who had undergone the OncotypeDx ® and MammaPrint ® genetic tests. These variables and factors included in the tests were categorised and weighted to obtain scores between 1 and 5 pointsto represent a lower or higher risk of relapse, respectively, based on these factors and as determined by the researchers.

Results

The mean follow-up time was 60.5 months (range 25–96 months); locoregional progression-free survival at the time of the analysis was 98.4%, and overall survival was 97.5%, of which 0.6% of the deaths had been cancer specific. The area under the curve for the PersonalRT27 was 0.76 (95% CI [0.70, 0.81]), sensitivity was 78%, and the specificity was 58.9%. We used these factors to create an inhospital web-based nomogram.

Conclusions

The PersonalRT27 is a novel tool that integrates clinical-pathological, molecular, and genetic parameters. External and independent validation will be required to implement its clinical use.

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Genomic assays impact the choice of adjuvant systemic treatment for patients with early-stage breast cancer.

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However, the same evidence does not exist for decision making regarding adjuvant locoregional therapy.

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In other words, can the clinically approved genomic assays predict the risk of locoregional recurrende as a primary event.

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The main objective of this work was to identify the clinicopathological, molecular, and genetic parameters that allow patients to be more precisely categorised into risk groups, in order to create a locoregional recurrence risk-classification tool, the PersonalRT27.

OPTimizing Irradiation through Molecular Assessment of Lymph node (OPTIMAL): a randomized open label trial

BACKGROUND

Conservative surgery followed by breast and nodal irradiation is the standard loco-regional early breast cancer (BC) treatment for patients with four or more involved lymph nodes. However, the treatment strategy when fewer nodes are involved remains unclear, especially when lymphadenectomy has not been performed. Sensitive nodal status assessment molecular techniques as the One-Step Nucleic Acid Amplification (OSNA) assay can contribute to the definition and standardization of the treatment strategy. Therefore, the OPTIMAL study aims to demonstrate the feasibility of incidental irradiation of axillary nodes in patients with early-stage BC and limited involvement of the SLN.

METHODS

BC patients who underwent conservative surgery and whose SLN total tumour load assessed with OSNA ranged between 250-15,000 copies/µL will be eligible. Patients will be randomized to receive irradiation on the breast, tumour bed, axillary and supraclavicular lymph node areas (intentional arm) or only on the breast and tumour bed (incidental arm). All areas, including the internal mammary chain, will be contoured. The mean, median, D5% and D95% doses received in all volumes will be calculated. The primary endpoint is the non-inferiority of the incidental irradiation of axillary nodes compared to the intentional irradiation in terms of 5-year disease free survival. Secondary endpoints comprise the comparison of acute and chronic toxicity and loco-regional and distant disease recurrence rates.

DISCUSSION

Standardizing the treatment and diagnosis of BC patients with few nodes affected is crucial due to the lack of consensus. Hence, the quantitative score for the metastatic burden of SLN provided by OSNA can contribute by improving the discrimination of which BC patients with limited nodal involvement can benefit from incidental radiation as an adjuvant treatment strategy.

TRIAL REGISTRATION

ClinicalTrial.gov, NCT02335957; https://clinicaltrials.gov/ct2/show/NCT02335957.

Sobreimpresión en fracción única con braquiterapia intersticial de alta tasa en el tratamiento conservador del carcinoma de mama

INTRODUCTION

We evaluated the effectiveness of interstitial high dose rate brachytherapy as a single fraction boost to the surgical bed in patients with breast cancer undergoing conservative treatment. The comparison was with the alternative of electron boost.

MATERIALS AND METHODS

Between April 1999 and December 2000, we conducted a prospective study of 84 patients with infiltrative breast carcinoma treated with conservative surgery, with free margins. This was followed by external radiotherapy to the breast of up to 46 Gy and one application of brachytherapy with needles inserted into the surgical bed, and administering 7 Gy to 90% with high dose rate (HDR).

RESULTS

With a mean follow-up of 43 months, only one patient had therapeutic failure in the implant area, and local control was 98.5%. Another patient had a 2nd tumour in a different quadrant and 3 developed metastasis. Survival at 5 years was 98.7%. Acute toxicity was minimal, with excellent or good cosmetic appearance in 95%.

CONCLUSIONS

Brachytherapy with high dose rate as single fraction boost in conservative treatment of breast carcinoma is simple, fast, well tolerated, with excellent local control, good cosmetic appearance, and with minimal late-onset toxicity.