Clinical outcome of patients with lymph node-negative breast carcinoma who have sentinel lymph node micrometastases detected by immunohistochemistry.
BACKGROUND
The ideal pathologic assessment of sentinel lymph nodes (SLNs) in patients with breast carcinoma remains controversial. The authors evaluated how detailed assessment of SLNs using immunohistochemistry (IHC) and serial sectioning would affect treatment decisions and outcomes in patients with breast carcinoma who had negative SLNs on standard hematoxylin and eosin staining.


METHODS
The SLNs from patients who were treated between June 1998 and June, 1999 and who had negative lymph node status determined by hematoxylin and eosin staining (n = 84 patients) were evaluated further with serial sectioning and cytokeratin IHC. Patients were offered adjuvant therapy based on primary tumor factors.


RESULTS
The median patient age was 57 years, and the median tumor size was 1.2 cm. At a median follow-up of 40.2 months, 81 patients (96%) were alive with no evidence of disease, 1 patient was alive with disease, 1 patient had died of disease, and 1 patient had died of other causes. Fifteen patients (18%) had micrometastases identified on IHC. Of the total 84 patients, information regarding adjuvant therapy was not available for 5 patients. Of the remaining 79 patients, 10 patients (13%) were not offered adjuvant chemotherapy but had positive SLN status determined by IHC. SLN status based on IHC evaluation did not correlate with age (P = 0.077), tumor size (P = 0.717), grade (P = 0.148), estrogen receptor status (P = 1.000), or lymphovascular invasion (P = 0.274). Furthermore, IHC-detected positive SLN status did not correlate with distant metastasis (P = 0.372) or overall or distant metastasis-free survival (P = 0.543 and P = 0.540, respectively).


CONCLUSIONS
Although the finding of SLN micrometastases by IHC may change management in > 12% of patients, preliminary results suggested that such micrometastases do not affect outcomes significantly.
Chagpar
Anees
A
Department of Surgical Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
Middleton
Lavinia P
LP
Sahin
Aysegul A
AA
Meric-Bernstam
Funda
F
Kuerer
Henry M
HM
Feig
Barry W
BW
Ross
Merrick I
MI
Ames
Frederick C
FC
Singletary
S Eva
SE
Buchholz
Thomas A
TA
Valero
Vincente
V
Hunt
Kelly K
KK
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology; D018275:Carcinoma, Lobular / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008875:Middle Aged; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D021701:Sentinel Lymph Node Biopsy; D015996:Survival Rate; D016896:Treatment Outcome