The clinical role of micrometastatic disease in sentinel lymph nodes in breast cancer.

Purpose: Complete axillary lymph node dissection (cALND) is the standard procedure in treating the patients with tumor-positive sentinel nodes (SLNs). However, approximately half of these patients have not additional metastases in their axilla and therefore do not benefit from cALND. Our aim was to examine the outcome of patients with tumor-positive SLNs without cALND.

Methods: All patients (n=591) were women with clinically T1-2N0-1M0 breast cancer. SLN marking was performed with blue dye (Patentblau V) and radiotracer (antimony sulfide marked with Tc99m). Both contrast media were applied peritumorally or periareolarly. After SLN biopsy all patients underwent breast-conserving surgery or mastectomy with or without lymph node dissection of level I and II (depending on SLN status).

Results: In 37 (17.84%) out of 185 patients cases SLNs contained micrometastases. In 19 of 37 cases (57.58%) cALND was performed, and in 14 (42.42%) was not. The mean and median duration of follow-up were 50.59 and 55 months, respectively (range 4-108). Two cases without cALND developed ipsilateral enlarged lymph nodes at 26 and 59 months. Biopsy showed that the enlarged nodes were tumor-free. In all other cases with micrometastases in SLNs neither axillary lymphadenopathy nor distant metastases were seen. After performing surgical treatment, all patients received adjuvant chemotherapy or hormonotherapy and radiotherapy.

Conclusion: Patients with SLN micrometastases who had not undergone cALND showed no regional recurrence and distant metastases. ALND is not necessary for regional control in patients with micrometastatic or isolated tumor cells in SLNs. By avoiding cALND the number of complications was reduced and the quality of life was improved.