The location of small tumor deposits in the SLN predicts Non-SLN macrometastases in breast cancer patients.
OBJECTIVE
The extent to which the location of micrometastases (MIC) or isolated tumor cells (ITC) in sentinel lymph nodes (SLNs) is correlated with the risk of downstream metastases is still unknown. This study examined this issue and compared the impact of MIC/ITC location with other established risk factors.


METHODS
Paraffin slides of SLNs with MIC/ITC-involvement obtained from 68 breast cancer patients were evaluated for MIC/ITC location, lesion size, and various SLN morphologic features. These parameters, together with demographic data and primary tumor characteristics, were analyzed using univariate and multivariate analysis to determine their association with the presence of downstream macrometastases in Non-SLN.


RESULTS
Eighteen of 68 patients with MIC (n=37) or ITC (n=31) had Non-SLN metastases. After multivariate analysis, the location of MIC/ITC in the SLN (parenchyma vs. sinus/vessel) had the strongest association with the presence of Non-SLN macrometastases (p<0.0001), followed by the pT-category (p=0.008). Sixteen of 18 patients with parenchymal involvement but only 2 of 31 without parenchymal involvement had Non-SLN macrometastases. The metric size of the primary tumor and the estrogen receptor status were significantly associated only on univariate analysis (p=0.041, 0.034), whereas the correlation to the size classification for tumor cell deposits (MIC vs. ITC) was not significant (p=0.077).


CONCLUSIONS
The results indicate that lesion location is an important predictor of Non-SLN-macrometastases. This finding may simplify the decision for axillary treatment in patients with small tumor deposits in the SLN.
Li
J
J
Department of Surgery and Surgical Oncology, Robert-Roessle Cancer Center at the Max-Delbrueck-Center of Molecular Medicine, Charité University Medicine Berlin, Campus Buch, in "Helios Klinikum Berlin", Lindenberger Weg 80, D13125 Berlin, Germany.
Rudas
M
M
Department of Pathology, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
Kemmner
W
W
Department of Surgery and Surgical Oncology, Robert-Roessle Cancer Center at the Max-Delbrueck-Center of Molecular Medicine, Charité University Medicine Berlin, Campus Buch, in "Helios Klinikum Berlin", Lindenberger Weg 80, D13125 Berlin, Germany.
Warnick
P
P
Department of Surgery and Surgical Oncology, Robert-Roessle Cancer Center at the Max-Delbrueck-Center of Molecular Medicine, Charité University Medicine Berlin, Campus Buch, in "Helios Klinikum Berlin", Lindenberger Weg 80, D13125 Berlin, Germany.
Fischer
J
J
Department of Electronic Data Processing & Statistics, Robert-Roessle Cancer Center at the Max-Delbrueck-Center of Molecular Medicine, Charité University Medicine Berlin, Campus Buch, in "Helios Klinikum Berlin", Lindenberger Weg 80, D13125 Berlin, Germany.
Gnant
M
M
Department of Surgical-Experimental Oncology in the Department of Surgery, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
Schlag
P M
PM
Department of Surgery and Surgical Oncology, Robert-Roessle Cancer Center at the Max-Delbrueck-Center of Molecular Medicine, Charité University Medicine Berlin, Campus Buch, in "Helios Klinikum Berlin", Lindenberger Weg 80, D13125 Berlin, Germany.
Bembenek
A
A
Department of Surgery and Surgical Oncology, Robert-Roessle Cancer Center at the Max-Delbrueck-Center of Molecular Medicine, Charité University Medicine Berlin, Campus Buch, in "Helios Klinikum Berlin", Lindenberger Weg 80, D13125 Berlin, Germany. Electronic address: andreas.bembenek@charite.de.
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis / Q000473:pathology; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000473:pathology; D012307:Risk Factors; D021701:Sentinel Lymph Node Biopsy