Standard or Hypofractionated Radiotherapy Versus Accelerated Partial Breast Irradiation (APBI) for Breast Cancer (SHARE)

Phase III Multicentric Trial Comparing Accelerated Partial Breast Irradiation (APBI) Versus Standard or Hypofractionated Whole Breast Irradiation in Low Risk of Local Recurrence of Breast Cancer

The standard treatment for localized breast cancer is based on conservative surgery (when possible) followed by radiation therapy (RT) delivered to the whole breast. The recommended total RT dose is 45 to 50 Gy delivered in 4.5 to 5 weeks followed by a 10 to 16 Gy boost to the tumor bed for 1 to 1.5 weeks. The rationale for the development of APBI was based on the difficulty for many patients to reach RT centers to receive standard whole breast irradiation (WBI) after conservative surgery. APBI offers decreased overall treatment time and several theoretical advantages over WBI, including a decrease in dose delivered to uninvolved portions of the breast and adjacent organs. If equivalence between the two treatments can be shown, then APBI will be considered as a historic evolution in breast cancer management.

In this phase III trial, designed in postmenopausal women >50 years of age, the objective is to compare the effectiveness and safety of APBI compared with whole breast irradiation. This study is also designed to ensure high quality criteria for surgery, pathology and RT techniques in the 3 arms and will allow to provide data on economics and costs.

Study Overview

• Status: Active, not recruiting
• Conditions: Breast Cancer; Lumpectomy
• Intervention / Treatment: Radiation: Whole Breast Irradiation + Boost or Hypofractionated irradiation; Radiation: Accelerated partial breast irradiation

Detailed Description

Following breast conservative surgery, patients will be stratified according to the following prognostic factors using a minimisation technique: age (<70 vs ≥70), HER2 status (HER2+ vs HER2-), hormonal receptor status (RH+ vs RH-) and lymph node invasion (pN0 vs pN0i+).

Patients will be allocated to receive either standard treatment, hypofractionated treatment or APBI.

Radiation therapy should be started between 4 and 12 weeks after the last surgery.

Patients treated with standard whole breast irradiation will receive a total dose of 50 Gy in 25 fractions, 2 Gy per day, 5 days a week. The boost of 16 Gy will be delivered in 8 fractions for all patients after completion of the 50 Gy, without interruption. All patients will receive one fraction per day, 5 fractions a week.

Patients treated with hypofractionated irradiation will receive a total dose of either 40 Gy (in 15 fractions, 2.66 Gy per day) or 42.5 Gy (in 16 fractions, 2.65 Gy per day) 5 days a week.

Patients treated with APBI will receive a total dose of 40 Gy in 10 fractions, delivered twice a day over a time period of 5-7 days. Each daily dose must be separated by 6 hours.

Patients will be followed at 3 and 6 month after the last dose of irradiation, at 12 months after the date of last surgery and then on a yearly basis during 10 years.

• Study Type: Interventional
• Enrollment (Actual): 1006
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • Amiens, France
    • Centre Hospitalier Universitaire
  • Amiens, France
    • Centre de traitement des Hautes energie - Clinique de l'Europe
  • Bordeaux, France
    • Institut Bergonie
  • Brive, France
    • Centre hospitalier
  • Caen, France
    • Centre Francois Baclesse
  • Chambery, France
    • CH Chambery
  • Creteil, France, 94010
    • Hôpital Henri Mondor
  • Dechy, France
    • Centre Leonard de Vinci
  • Grenoble, France
    • CHU Michallon
  • Libourne, France
    • Hôpital Robert Boulin
  • Lille, France, 59020
    • Centre Oscar Lambret
  • Limoges, France
    • Chu Dupuytren
  • Lyon, France
    • Centre Leon Berard
  • Marseille, France
    • Institut Paoli Calmettes
  • Montauban, France
    • Clinique du Pont de Chaume
  • Montpellier, France
    • CRLC Val d'Aurelle
  • Montélimar, France
    • Centre hospitalier
  • Mulhouse, France
    • Centre Hospitalier de Mulhouse
  • Nancy, France
    • Centre d'oncologie de Gentilly
  • Neuilly sur Seine, France
    • Clinique Hartmann
  • Nice, France
    • Centre de Haute Energie
  • Paris, France
    • Saint Louis Hospital
  • Paris, France
    • Hôpital Tenon
  • Paris, France
    • Groupe Hospitalier Pitié Salpêtrière
  • Perpignan, France
    • Centre Catalan d'Oncologie
  • Reims, France
    • Institut Jean Godinot
  • Rennes, France
    • Centre Eugene Marquis
  • Roanne, France
    • CH de ROANNE
  • Rouen, France
    • Centre Henri Becquerel
  • Saint Priest en Jarez, France
    • Institut de Cancerologie de La Loire
  • Strasbourg, France
    • Centre Paul Stauss
  • Valence, France
    • Centre Marie Curie
  • Vandoeuvre les Nancy, France
    • Centre Alexis Vautrin
  • Villejuif, France
    • Institut Gustave Roussy

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Women aged ≥50 years
• Menopausal status confirmed
• Pathology confirmation of invasive carcinoma (all types)
• Complete tumor removal and conservative surgery
• Pathologic tumor size of invasive carcinoma ≤2 cm (including the in situ component) pT1
• All histopathologic grades
• Clear lateral margins for the invasive and in situ disease (>2 mm)
• pN0 or pN(i+)
• No metastasis
• Radiotherapy should be started more than 4 weeks and less than 12 weeks after last surgery
• Surgical clips (4 to 5 clips in the tumor bed)
• No prior breast or mediastinal radiotherapy
• Eastern Cooperative Oncology Group (ECOG) 0-1
• Information to the patient and signed informed consent

Exclusion Criteria:

• Multifocal invasive ductal carcinoma defined as the presence of at least two distinct tumors that are separated by normal tissue or when the distance between the two lesions does not permit conservative surgery
• Bilateral breast cancer
• No or less than 4 surgical clips in the tumor bed
• Nodal involvement : pN1 (including micrometastasis, mi+), pN2, pN3
• Metastatic disease
• internal mammary node involvement or supraclavicular lymph node involvement
• Indication of chemotherapy or trastuzumab
• Involved or close lateral margins for the invasive and /or in situ components (<2 mm) AND impossibility to re-operate or impossible to perform another conservative surgery
• Patients with known BRCA1 or BRCA2 mutations
• Previous mammoplasty
• Previous homolateral breast and/or mediastinal irradiation
• Previous invasive cancer (except basocellular epithelioma or in situ carcinoma of the cervix)
• No geographical, social or psychologic reasons that would prevent study follow

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Standard or Hypofractionated radiotherapy; Whole breast RT, 50 Gy + "boost" 16 Gy. Whole breast hypofractionated RT without boost, either 40 Gy or 42.5 Gy	Radiation: Whole Breast Irradiation + Boost or Hypofractionated irradiation; Whole Breast Irradiation 50 Gy + Boost 16 Gy or Whole breast, either 40 Gy in 15 fractions in 3 weeks or 42.5 Gy in 16 fractions in 3 weeks; Other Names: Standard radiation
Experimental: Accelerated Partial Breast Irradiation (APBI); APBI using 3D CRT technique, in 5 days, 38.5 Gy to the tumor bed	Radiation: Accelerated partial breast irradiation; Tumor bed 40 Gy in 10 fractions, 2 fractions of 4 Gy per day in 5 to 7 days.; Other Names: APBI

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
rate of local recurrence	To estimate and compare the rate of local recurrence between the experimental and control arms.	5 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ipsilateral breast recurrence-free survival	To evaluate Ipsilateral breast recurrence-free survival	10 years
Nodal regional recurrence-free survival	To evaluate nodal regional recurrence-free survival	10 years
Distant recurrence-free survival	To evaluate distant recurrence-free survival	10 years
Disease-specific survival	To evaluate disease-specific survival	10 years
Overall survival	To evaluate the overall survival	10 years
Toxicities: Measurement of the rate and type of toxicity (acute and late toxic effects)	To evaluate rates and type of acute and late toxicities	10 years
Cosmetic: comparison of the cosmetic result (according to both the physician and the patient)	To evaluate Cosmetic results (Patient and Physician evaluations)	10 years
Quality of Life and Satisfaction	To evaluate the patient quality of life and patient satisfaction	10 years
Medico-economic study	To evaluate the cost of APBI compared with Standard and Hypofractionated irradiation	3 years

Collaborators and Investigators

• Sponsor: UNICANCER
• Investigators: Principal Investigator: Yazid Belkacemi, MD PhD, Henri Mondor Hospital AP-HP, Créteil, France; Principal Investigator: Eric Lartigau, MD, Oscar Lambret Hospital, Lille, France; Principal Investigator: Céline Bourgier, MD, Institut de Cancérologie de Montpellier, Montpellier, France

Publications and helpful links

General Publications

• Belkacemi Y, Bourgier C, Kramar A, Auzac G, Dumas I, Lacornerie T, Mege JP, Mijonnet S, Lemonnier J, Lartigau E. SHARE: a French multicenter phase III trial comparing accelerated partial irradiation versus standard or hypofractionated whole breast irradiation in breast cancer patients at low risk of local recurrence. Clin Adv Hematol Oncol. 2013 Feb;11(2):76-83.

Study record dates

Study Major Dates

• Study Start (Actual): December 27, 2010
• Primary Completion (Actual): December 7, 2020
• Study Completion (Estimated): October 1, 2025

Study Registration Dates

• First Submitted: October 26, 2010
• First Submitted That Met QC Criteria: November 23, 2010
• First Posted (Estimated): November 24, 2010

Study Record Updates

• Last Update Posted (Actual): May 14, 2025
• Last Update Submitted That Met QC Criteria: May 9, 2025
• Last Verified: May 1, 2025

More Information

Terms related to this study

• Keywords: breast cancer; Lumpectomy; Accelerated Partial Breast Irradiation; invasive cancer; Hypofractionated Irradiation
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Skin Diseases; Breast Diseases; Breast Neoplasms
• Other Study ID Numbers: RTS02-SHARE; 2010-A00243-36 (Other Identifier: ID-RCB); UC-0140/1001 (Other Identifier: UNICANCER); RTS02 / SHARE (Other Identifier: UNICANCER)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Unicancer will share de-identified individual data that underlie the results reported. A decision concerning the sharing of other study documents, including protocol and statistical analysis plan will be examined upon request.
• IPD Sharing Time Frame: Unicancer will consider access to study data upon written detailed request sent to Unicancer, from 6 months until 5 years after publication of summary data.
• IPD Sharing Access Criteria: The data shared will be limit to that required for independent mandated verification of the published results, the applicant will need authorization from Unicancer for personal access, and data will only be transferred after signing of a data access agreement.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP