Radiation Therapy After Surgery in Treating Women With Phyllodes Tumor of the Breast

OBJECTIVES:

- Determine the local recurrence rate in women with phyllodes tumors of the breast
previously treated with local excision with negative margins and are now treated with
adjuvant radiotherapy.

- Determine the survival rate in patients treated with this regimen.

METHODS: Within 12 weeks after prior local excision or breast reexcision, patients underwent
adjuvant radiotherapy 5 days a week for a total of 28 treatments. Patients were then followed
every 6 months for 10 years.

DISEASE CHARACTERISTICS:

1. Histologically proven phyllodes tumors of the breast with borderline or malignant
grade, defined as 1 of the following:

1. Borderline, defined as 5-9 mitoses/10 high power fields (HPF), pushing or
infiltrating margins, 2+ atypia

2. Malignant, defined as 10 or more mitoses/10 HPF, predominantly infiltrating
margins, usually 3+ atypia with occasional 2+ atypia

2. Must have been excised with breast-conserving resection and no positive margins

3. Local recurrence of a previously excised phyllodes tumor allowed if the recurrence is
in the area of the prior excision

4. No prior breast carcinoma or ductal carcinoma in situ in the ipsilateral breast

5. Hormone receptor status: Not specified

PATIENT CHARACTERISTICS:

1. Age: 18 and over

2. Sex: Female

3. Menopausal status: Not specified

4. Performance status: Not specified

5. Life expectancy: Not specified

6. Hematopoietic: Not specified

7. Hepatic: Not specified

8. Renal: Not specified

9. Other:

1. Not pregnant

2. Negative pregnancy test

3. Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

1. Biologic therapy: Not specified

2. Chemotherapy: Not specified

3. Endocrine therapy: Not specified

4. Radiotherapy: No prior radiotherapy to the ipsilateral breast

5. Surgery: See Disease Characteristics