INDICATION OF BREAST CONSERVATIVE SURGERY FOR PRIMARY BREAST CANCER USING COMPUTER GRAPHIC THREE-DIMENSIONAL RECONSTRUCTION OF THE MAMMARY DUCT-LOBULAR SYSTEMS.

乳腺癌导管内扩散可沿乳腺导管/乳腺小叶系统（MDLS）发生，不侵犯组织。由于MDLS的导管吻合术被认为是乳腺癌导管内广泛扩散的可能危险因素，因此MDLS的结构对保乳手术患者具有重要的治疗意义。我们用体视显微镜和组织学技术在亚大体切片上检查了一位69岁的导管原位癌（DCIS）患者的整个乳房。连续2-mm切片进行计算机辅助完整的MDLS三维重建。整个乳房包含16个MDLS，以乳头为中心呈放射状排列。16例MDLS中有导管吻合4例（25.0%），其余12例无导管吻合，区域解剖完全独立。4个MDLS中11个部位有导管吻合。11个导管吻合口中2个（18.2%）位于距乳头4cm以上的位置。其余9条在同一MDLS内相连的管道；它们的位置从乳头附近到周围区域不等。在本病例中，DCIS仅在单个MDLS内扩展，并没有通过导管吻合口在不同MDLS之间扩散。据作者所知，首次对整个乳房中所有MDLS的完整结构进行了三维研究。当导管内病变向周围而非中心扩散时，手术中导管内扩散扩大的风险可能更大。基于MDLS解剖结构的个体化手术切除范围有助于减少手术边缘残留癌的风险。

Intraductal spread of breast cancer can occur along the mammary duct/lobular systems (MDLS) with no invasion of tissues. As ductal anastomoses in the MDLS are considered a possible risk factor for extensive intraductal spread of breast cancer, the architecture of MDLS has important therapeutic implications for patients treated by breast-conserving surgery. An entire breast resected by subcutaneous mastectomy from a 69-year-old woman with ductal carcinoma in situ (DCIS) was examined in subgross sections by stereomicroscopic and histologic techniques. Serial 2-mm sections were subjected to computer-assisted complete three-dimensional reconstruction of all MDLS. The entire breast used contained 16 MDLS, radially arranged with the nipple at the center. Of 16 MDLS, 4(25.0%) had ductal anastomoses while the remaining 12 MDLS had no ductal anastomoses and completely independent regional anatomy. Ductal anastomoses were observed at 11 sites in the 4 MDLS. The 2 (18.2%) of 11 ductal anastomoses that connected different MDLS were situated more than 4 cm from the nipple. The remaining 9 connected ducts within the same MDLS ; their location varied from near the nipple to the peripheral region. In the case examined, DCIS extended only within a single MDLS, and did not spread between different MDLS via ductal anastomoses. The complete architecture of all MDLS in an entire breast was studied three-dimensionally for the first time to the authors' knowledge. The risk of extending intraductal spread during surgery may be greater where intraductal lesions extend more peripherally than centrally. Individualizing the extent of surgical resection based on the anatomy of MDLS should help to minimize the risk of leaving residual carcinoma at surgical margins.