title: False-positive and false-negative sentinel node findings in 473 breast cancers.
abstract: We reviewed lymph node samples from 473 consecutive breast cancer cases with either negative sentinel nodes or isolated tumor cells to evaluate the rate of false-positive sentinel node findings. Nuclear morphometry was applied to compare nuclear atypia between the primary tumor and metastases classified as isolated tumor cells by size. In addition, the role of the diagnostic preoperative biopsy method, either core needle biopsy or fine needle aspiration cytology, on the prevalence of isolated tumor cells was investigated. In addition, we studied the expression of metastasis-associated protein 1 in the primary tumor and corresponding metastases in 95 cases, including 52 isolated tumor cell cases, to distinguish a true metastasis from a benign epithelial displacement. Our review revealed 4 false positives and 7 false negatives from 473 sentinel node cases. In addition, 5 true-positive cases were upstaged from isolated tumor cells to micrometastases. No association was found between the preoperative biopsy method and the sentinel node status (P=.859). There was no difference in nuclear atypia, when the cells in isolated tumor cells and primary tumor were compared. Therefore, small metastases do not represent benign epithelial displacement. Isolated tumor cell findings did not correlate with preoperative biopsy methods. The metastasis-associated protein 1 staining score sum was lower in the metastases than in the primary tumor in 72% of cases, including all sizes of metastases. These data suggest that metastasis-associated protein 1 staining is not ideal for investigating the possible malignant nature of smaller metastases because of the relatively low concordance between the primary tumor and metastases, even macrometastases.
authors.affiliation: Department of Pathology, Helsinki University Central Hospital, and University of Helsinki, Haartman Institute, Helsinki, Finland. leena.strien@hus.fi
authors.forename: Leena
authors.initials: L
authors.lastname: Strien
authors.forename: Marjut
authors.initials: M
authors.lastname: Leidenius
authors.forename: Päivi
authors.initials: P
authors.lastname: Heikkilä
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000556:secondary*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000378:metabolism / Q000473:pathology; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000378:metabolism / Q000556:secondary*; D003951:Diagnostic Errors; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006655:Histone Deacetylases / Q000378:metabolism; D006801:Humans; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis / Q000175:diagnosis; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011237:Predictive Value of Tests; D012097:Repressor Proteins / Q000378:metabolism; D021701:Sentinel Lymph Node Biopsy; D015534:Trans-Activators; D055815:Young Adult
chemical_list: C089320:MTA1 protein, human; D012097:Repressor Proteins; D015534:Trans-Activators; D006655:Histone Deacetylases