Determination of the accuracy of juxtacapsular dissection of the breast. What is left behind?

BACKGROUND Resectional breast surgery has become less extensive. Dissection on plane of the superficial fascia covering the breast (juxtacapsular) is used during various procedures for retention of the appearance of the breast. The accuracy of this method and its ability to remove all glandular breast tissue has never been tested. METHODS Twenty patients with breast cancer were studied prospectively. Juxtacapsular dissection of the inferior flap was performed during mastectomy. Biopsies were taken on each side of the dissection plane at 3 sites: median, medial and lateral. Several histological slides were prepared from each biopsy and examined for the presence of breast parenchymal or dispersed glandular tissue. RESULTS Three hundred and forty nine histological slides were examined, 185 from the resected breast side and 164 from the subcutaneous side. Ninety four percent of the slides from the breast side contained glandular tissue. Breast glandular tissue was found outside the dissection plane in 16 of 20 cases and in 33% of slides. This was sparse and dispersed in 69% of slides. A mean of 81% of slides from individual cases revealed glandular tissue inside and the absence of glandular tissue outside the dissection plane ("expected result"), demonstrating predominantly accurate juxtacapsular dissection. CONCLUSION This study demonstrated that accurate juxtacapsular inferior flap dissection leaves behind glandular breast tissue in a greater proportion of cases than any previous study. While this tissue is sparsely-distributed, surgeons should be aware of the occurrence of glandular breast tissue outside the juxtacapsular dissection plane in the majority of cases.