Non invasive breast lesions – the clinical standpoint

Non-invasive breast lesions (NIBL) have gained more and more importance due to increasing use of screening mammography in western industrialized countries. Ductal carcinoma in situ (DCIS) remains a surgical challenge following the same indication for breast conservation as invasive breast cancer. In order to minimize local failure rates a free resection margin of at least 1mm to 5mm (ideally 10mm) should be reached. In case of disseminated pathologic microcalcifications, lesions in different quadrants of the breast and involvement of the nipple an ablative procedure is standard of care. Secondary ablation is indicated after failure to gain free margins with a reasonable number of re-excisions. Sentinal node biopsy is indicated in ablative surgical procedures and when micro-invasion is diagnosed in pre-operative biopsy. Post-operative Irradiation is the standard of care in breast conserving therapy in DCIS. In selected patients with small low grade lesions who are older than 40yrs of age and wide resection margins Irradiation therapy could be ommited after informed consent. Adjuvant hormonal treatment with Tamoxifen is an option for premenopausal patients with hormone responsive lesions. It should also be considered for younger post-menopausal patients with high grade lesions especially when hysterectomized. Lobular intraepithelial neoplasia (LIN) is characterized by tendency to multi-focality/centricity and bilaterality. Generally this lesion is considered as a risk marker for the development of sequential invasive breast cancer (indicator lesion) as well as a precursor lesion for invasive lobular cancer. This is especially true for the pleomorphic subtypes (LIN 3). In case of a LIN 1 or 2 as an incidential finding in a histological specimen prophylaxis with Tamoxifen should be considered. On the other hand LIN 3 has to be treated surgically with free resection margins.