The purpose of this study is to determine if wide excision (surgical removal) alone is adequate treatment for small, grade 1 or 2 ductal carcinoma in situ (DCIS) of the breast.

• Patients with DCIS are usually treated with the combination of breast-conserving surgery and radiation therapy or breast-conserving surgery alone. The purpose of this study is to evaluate whether localized low- or intermediate-grade DCIS, diagnosed with modern mammography and careful pathologic evaluation, could be treated with wide excision alone (omission of radiation therapy) and result in acceptably low local recurrence rates.
• Follow-up consists of physical examinations at least every 6 months by the surgeon or radiation oncologist. Mammograms of the affected breast will be obtained every 6 months for 5 years and then annually. Mammograms of the unaffected breast will be performed annually.

Inclusion Criteria:

• Patients must have high quality mammogram including magnification views of the area containing suspicious calcifications.
• A specimen radiograph is required. If the specimen radiograph does not assure removal of all suspicious microcalcifications, a post-operative mammogram showing removal of all suspicious calcifications is required.
• The clinical extent of DCIS must be less than or equal to 2.5 cm.
• Grade 1 or 2 DCIS; patients with lobular carcinoma-in-situ (LCIS) in addition to DCIS in the breast are eligible. Negative margins are not required on the LCIS.
• Patients must undergo a wide excision. A re-excision after the initial biopsy might be needed. Complete resection of the area of DCIS with a histologic margin of at least 1 cm must be achieved.
• Patients must be enrolled on this protocol within 3 months of the last surgical procedure.

Exclusion Criteria:

• Patients with invasive carcinoma including microinvasive disease
• Carcinoma found in the sampled lymph nodes if axillary dissection is done
• Patients with nipple discharge
• Patients with adjuvant chemotherapy or Tamoxifen
• Patients with a history of prior malignancies other than squamous or basal cell carcinoma of the skin, or carcinoma in situ of the cervix.
• Patients with a history of ipsilateral or contralateral breast carcinoma or DCIS or simultaneous bilateral DCIS.