Prospective Study on Exemption of Tumor Bed Boost Radiotherapy for pCR Patients After Breast Conserving Surgery With Neoadjuvant Therapy

NCT07113613 | Recruiting Phase 2

• 1 other identifier: 2024-SR-983
• Study Type: interventional
• Target: 150
• Locations: 1 country
• Sites: 1

Brief Summary

This study is a multicenter, single-arm, phase II clinical trial, aiming to evaluate the safety and efficacy of tumor bed dose escalation radiotherapy for patients with primary breast lesions achieving pCR (ypT0) after neoadjuvant chemotherapy and breast-conserving surgery.

Conditions

Breast Cancer

Keywords

Radiotherapy; Exemption of tumor bed dosage increase; Breast-conserving treatment; Neoadjuvant chemotherapy

Outcome Measures

Primary Outcomes (2)

• 5-year ipsilateral breast recurrence rate (IBTR)

  The recurrence of the same-sided breast occurred for the first time within 5 years.

  5 years

• 5-year local-regional recurrence (LRR)

  Recurrence of the same-side breast, the same-side axillary fossa, the same-side supraclavicular lymph nodes, or the same-side internal mammary lymph nodes for the first time within 5 years.

  5 years

Secondary Outcomes (6)

• Local regional control rate (LRC)

  5 years

• Disease-free survival time (DFS)

  5 years

• Overall survival time (OS)

  5 years

• Safety-related study endpoints

  5 years

• cosmetic effect

  5 years

Study Arms (1)

Exempted tumor bed radiotherapy group

EXPERIMENTAL

The total breast irradiation dose was 43.5 Gy/15 fractions, with each fraction being 2.9 Gy, administered once a day, 5 times a week; the dose for the regional lymph nodes was also 43.5 Gy/15 fractions, with each fraction being 2.9 Gy, administered once a day, 5 times a week.

Radiation: Exemption from additional radiotherapy on the tumor bed after surgery

Interventions

Exemption from additional radiotherapy on the tumor bed after surgery RADIATION

For patients who met the inclusion criteria and were enrolled, postoperative tumor bed boost radiotherapy was waived, and only whole breast and/or regional lymph node irradiation was administered.

Exempted tumor bed radiotherapy group

Eligibility Criteria

• Age: 30 Years - 75 Years
• Gender Eligibility Details: This study only included female breast cancer patients.
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• (1) Voluntary participation, good compliance, able to cooperate with the trial observation, and having signed a written informed consent form; (2) Confirmed as invasive cancer through pathological tissue examination, and received baseline breast MR or PET/MR examination before neoadjuvant therapy; (3) Received the standard neoadjuvant treatment plan recommended by the guidelines based on molecular typing; (4) Single lesion, initially diagnosed as cT1-3N0-3a; (5) Underwent breast-conserving surgery, with negative surgical margins and a margin distance of ≥1mm, and achieved pCR of the primary breast lesion after NAC (ypT0); (6) Age 30-75 years, ECOG score 0-1; (7) Met the basic requirements for adjuvant radiotherapy, including basically normal peripheral blood count, no significant abnormalities in heart, liver, and kidney functions, and basically normal electrocardiogram; (8) Had no previous chest radiotherapy.

You may not qualify if:

• (1) Pregnant women, lactating women, or women with reproductive capacity but without contraceptive measures in place; (2) Known to carry mutated susceptibility genes for breast cancer (including BRCA-1 and BRCA-2); (3) Diagnosed with cT4, N3b-c, bilateral breast cancer, with multiple primary lesions, multicentricity or non-bulky enhancement at the primary site; (4) Not receiving the standard neoadjuvant treatment regimen recommended by guidelines, or the primary breast lesion did not achieve pCR (including ypTis) after NAC; (5) Suffering from other malignant tumors or participating in other clinical trials simultaneously; (6) Unable to start radiotherapy within 8 weeks after breast cancer surgery; (7) Diagnosed with distant metastasis through initial imaging or pathology; (8) Previous history of breast cancer, history of radiotherapy in the neck, chest or ipsilateral axilla; (9) Severe non-tumor-related medical comorbidities affecting the implementation of radiotherapy; (10) Suffering from uncontrollable neurological, mental disorders or mental impairments, with poor compliance and inability to cooperate and describe treatment responses.

Sponsors & Collaborators

• The First Affiliated Hospital with Nanjing Medical University: lead

Study Sites (1)

The First Affiliated with Nanjing Medical University (Jiangsu Province People's Hospital)

Nanjing, Jiangsu, 210029, China

RECRUITING

MeSH Terms

Conditions

Breast Neoplasms

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases

Study Officials

• Xinchen Sun, Doctor

  The First Affiliated with Nanjing Medical University (Jiangsu Province People's Hospital)

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Xinchen Sun, Doctor

CONTACT

13770662828; 13770662828@163.com

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Director of the Radiotherapy Center

Study Record Dates

• First Submitted: August 6, 2025
• First Posted: August 11, 2025
• Study Start: January 1, 2025
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2031
• Last Updated: August 11, 2025

Record last verified: 2025-08

Locations

CN (1)