Effects of Radiotherapy in Borderline and Malignant Phyllodes Tumors After R0 Resection

NCT06780059 | Completed

• 1 other identifier: SYSKY-2024-1127-01
• Study Type: observational
• Target: 480
• Locations: 1 country
• Sites: 3

Brief Summary

Breast phyllodes tumors (PT) are rare fibroepithelial neoplasms originating from stromal tissue and account for less than 1% of all breast tumors. The World Health Organization (WHO) classifies PT into benign, borderline, and malignant subtypes based on pathological features such as mitotic activity, cellular atypia, tumor margin invasion, and stromal composition 1. The presence of malignant heterologous elements characterizes the tumor as malignant 2. Surgery is the primary treatment. However, even after R0 resection, borderline phyllodes tumors (BoPT) and malignant phyllodes tumors (MPT) patients remain face a high risk of local recurrence, with rates of 15%-20% and 25%-30%, respectively. Moreover, metastases occur almost merely in MPT, with a distant metastasis rate reaching 22%. Adjuvant radiotherapy has attracted attention for its potential to improve local control and reduce recurrence, but the role after R0 resection in PT patients remains unclear. Radiotherapy significantly reduces local recurrence rates in BoPT and MPT but shows no substantial benefit in benign cases. However, a meta-analysis by Yu et al. found that this effect is limited to MPT. Additionally, the effect of radiotherapy on survival rates in PT remains controversial. Most existing studies are retrospective and face limitations such as small sample sizes. The rarity of PT and conflicting evidence of impact of radiotherapy necessitate further study. While prospective trials are difficult due to limited cases, well-designed retrospective studies can offer valuable insights. In this study, the investigators also analyzed prognostic factors and identified subgroups to provide a clinical reference for the application of postoperative radiotherapy in BoPT and MPT patients.

Conditions

Radiotherapy, Adjuvant; Phyllodes Breast Tumor; Prognosis

Outcome Measures

Primary Outcomes (1)

• 5-year Local Recurrence-free Survival

  The time period from the initial R0 resection to either the detection of local recurrence or the final follow-up.

  Five years

Secondary Outcomes (1)

• 5-year Overall Survival

  Five years

Study Arms (2)

Phyllodes tumors patients who received radiotherapy afte R0 resection

Radiation: Adjuvant Radiotherapy; Procedure: R0 resection

Phyllodes tumors patients who received R0 resection alone

Procedure: R0 resection

Interventions

Adjuvant Radiotherapy RADIATION

Postoperative Radiotherapy with 3D-CRT and IMRT Techniques Following R0 Resection in BoPT and MPT Patients

Phyllodes tumors patients who received radiotherapy afte R0 resection

R0 resection PROCEDURE

Patients who received R0 resection (complete resection without tumor margin)

Phyllodes tumors patients who received R0 resection alone; Phyllodes tumors patients who received radiotherapy afte R0 resection

Eligibility Criteria

• Sex: female
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients pathologically diagnosed with BoPT and MPT who underwent surgery at three medical institutions in China: Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Sun Yat-sen University Cancer Center, and the Third Affiliated Hospital of Nanchang University.

You may qualify if:

• patients who were initially diagnosed with BoPT or MPT and underwent R0 resection surgery

You may not qualify if:

• patients who had their initial surgery at other hospitals without accurate baseline data
• patients who received radiotherapy before surgery
• those presenting with initial distant metastasis before treatment
• patients lost to follow-up after treatment
• patients with a history of or concurrent breast cancer or precancerous lesions in the ipsilateral breast or with breast cancer in the contralateral breast

Sponsors & Collaborators

• Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University: lead

Study Sites (3)

Sun Yat-sen University Cancer Center

Guangzhou, Guangdong, 510050, China

Location

Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University

Guangzhou, Guangdong, 510120, China

Location

Third Hospital of Nanchang

Nanchang, Jiangxi, China

Location

Related Publications (9)

• Macdonald OK, Lee CM, Tward JD, Chappel CD, Gaffney DK. Malignant phyllodes tumor of the female breast: association of primary therapy with cause-specific survival from the Surveillance, Epidemiology, and End Results (SEER) program. Cancer. 2006 Nov 1;107(9):2127-33. doi: 10.1002/cncr.22228.

  PMID: 16998937 BACKGROUND

• Pandey M, Mathew A, Kattoor J, Abraham EK, Mathew BS, Rajan B, Nair KM. Malignant phyllodes tumor. Breast J. 2001 Nov-Dec;7(6):411-6. doi: 10.1046/j.1524-4741.2001.07606.x.

  PMID: 11843853 BACKGROUND

• Boutrus RR, Khair S, Abdelazim Y, Nasr S, Ibraheem MH, Farahat A, El Sebaie M. Phyllodes tumors of the breast: Adjuvant radiation therapy revisited. Breast. 2021 Aug;58:1-5. doi: 10.1016/j.breast.2021.03.013. Epub 2021 Apr 7.

  PMID: 33865208 BACKGROUND

• Yu CY, Huang TW, Tam KW. Management of phyllodes tumor: A systematic review and meta-analysis of real-world evidence. Int J Surg. 2022 Nov;107:106969. doi: 10.1016/j.ijsu.2022.106969. Epub 2022 Oct 31.

  PMID: 36328344 BACKGROUND

• Li J, Tsang JY, Chen C, Chan SK, Cheung SY, Wu C, Kwong A, Hu J, Hu H, Zhou D, Tse GM. Predicting Outcome in Mammary Phyllodes Tumors: Relevance of Clinicopathological Features. Ann Surg Oncol. 2019 Sep;26(9):2747-2758. doi: 10.1245/s10434-019-07445-1. Epub 2019 May 20.

  PMID: 31111353 BACKGROUND

• Belkacemi Y, Bousquet G, Marsiglia H, Ray-Coquard I, Magne N, Malard Y, Lacroix M, Gutierrez C, Senkus E, Christie D, Drumea K, Lagneau E, Kadish SP, Scandolaro L, Azria D, Ozsahin M. Phyllodes tumor of the breast. Int J Radiat Oncol Biol Phys. 2008 Feb 1;70(2):492-500. doi: 10.1016/j.ijrobp.2007.06.059. Epub 2007 Oct 10.

  PMID: 17931796 BACKGROUND

• Pezner RD, Schultheiss TE, Paz IB. Malignant phyllodes tumor of the breast: local control rates with surgery alone. Int J Radiat Oncol Biol Phys. 2008 Jul 1;71(3):710-3. doi: 10.1016/j.ijrobp.2007.10.051. Epub 2008 Jan 30.

  PMID: 18234448 BACKGROUND

• Moffat CJ, Pinder SE, Dixon AR, Elston CW, Blamey RW, Ellis IO. Phyllodes tumours of the breast: a clinicopathological review of thirty-two cases. Histopathology. 1995 Sep;27(3):205-18. doi: 10.1111/j.1365-2559.1995.tb00212.x.

  PMID: 8522284 BACKGROUND

• Md Nasir ND, Koh VCY, Cree IA, Ruiz BII, Del Aguila J, Armon S, Fox SB, Lakhani SR, Tan PH. Phyllodes tumour evidence gaps mapped from the 5th edition of the WHO classification of tumours of the breast. Histopathology. 2023 Apr;82(5):704-712. doi: 10.1111/his.14856. Epub 2023 Jan 30.

  PMID: 36579383 BACKGROUND

MeSH Terms

Conditions

Phyllodes Tumor

Interventions

Radiotherapy, Adjuvant

Condition Hierarchy (Ancestors)

Sarcoma; Neoplasms, Connective and Soft Tissue; Neoplasms by Histologic Type; Neoplasms

Intervention Hierarchy (Ancestors)

Combined Modality Therapy; Therapeutics; Radiotherapy

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: January 10, 2025
• First Posted: January 17, 2025
• Study Start: December 30, 2024
• Primary Completion: January 2, 2025
• Study Completion: January 2, 2025
• Last Updated: January 17, 2025

Record last verified: 2025-01

Data Sharing

• IPD Sharing: Will not share

Locations

CN (3)