PURE DUCTAL carcinoma in situ (DCIS) of the breast was infrequently diagnosed in the past, when it accounted for only 1% to 5% of all breast cancers. It usually presented as a palpable lesion, Paget disease, or bloody nipple discharge. Pure DCIS showed a 15-fold increase during the past 10 years, because of the widespread use of mammography for the detection of clinically nonpalpable tumors; now, it accounts for 20% or more of mammographically detected carcinomas^1-3 and 12% of all newly diagnosed breast cancers. Standard treatment of DCIS is wide resection, with or without postoperative radiotherapy. A total mastectomy can be required in cases of extensive intramammary spread. Axillary dissection is not routinely indicated because of the low prevalence of nodal metastases, which is expected to be less than 2%,⁴ and the significant morbidity associated with lymph node dissection.

The aim of this study is to assess the role of sentinel lymph node (SLN) biopsy in patients with pure ductal carcinoma in situ of the breast (DCIS) as a rationale for recommending the best managing option for the treatment of such patients in daily practice. DCIS cannot give rise to axillary metastases by definition. Axillary dissection is therefore not indicated. The role of SLN biopsy in the management of DCIS has not yet been established. From March 1996 to September 2006, 854 patients with pure DCIS underwent SLN biopsy at the European Institute of Oncology. Clinical and pathologic data were prospectively collected. When previous surgery or stereotactic biopsy had been performed elsewhere, all the histopathological preparations were reviewed. Patients with microinvasion were excluded from this investigation. Lymphatic mapping was performed using a radiocolloid technique. SLN metastases were detected in 12 (1.4%) DCIS patients. In 7 cases, only micrometastases (<2 mm) were diagnosed and in 5 cases macrometastases. In addition, isolated tumoral cells (ITC) (<0.2 mm) were identified in 4 additional patients. Eleven patients underwent complete axillary dissection. None of these patients had additional positive axillary lymph nodes. Because of the low prevalence of metastatic involvement, SLN biopsy should not be considered a standard procedure in the treatment of all patients with DCIS. The sole criteria for proposing SLN biopsy in DCIS should be when there exists any uncertainty regarding the presence of invasive foci at definitive histology.

At the European Institute of Oncology, Milan, Italy, we have focused our interest on the use of intraoperative radiation therapy (IORT) in limited-stage breast cancer that is conservatively treated. A new technique to perform IORT was applied in 185 patients from July 1, 1999, to October 31, 2001. As the surgeon plays a crucial role in this procedure in selecting the patients, performing the breast resection, preparing the gland as a target to receive IORT, delivering the radiation directly to the mammary gland via a dedicated applicator, and, finally, reconstructing the breast, each phase of the surgical technique has been completely standardized and is described herein. The use of IORT in the conservative treatment of breast cancer could allow the course of external fractionated-dose radiation therapy to be completely avoided; IORT dramatically reduces radiation exposure of the skin, lung, and subcutaneous tissues and avoids the irradiation of the contralateral breast, which contributes to a very low incidence of radiation-induced sequelae. In our experience, IORT for limited-stage breast carcinoma is easy to perform and only briefly prolongs the duration of the surgical procedure.