Intraoperative detection of lymph node micrometastasis with flow cytometry in non-small cell lung cancer.
OBJECTIVE
We sought to determine whether cytokeratin-positive cells can be detected as markers of lymph node metastasis by using flow cytometry within a time frame suitable for intraoperative decision making in non-small cell lung cancer.


METHODS
Five lymph nodes from each of 20 patients with non-small cell lung cancer were randomly selected for study. Each node was divided longitudinally into 3 pieces: one piece for flow cytometry, one for immunohistochemical staining, and the last for conventional hematoxylin and eosin staining. In both flow cytometry and immunohistochemistry, cytokeratin-positive cells were detected with the fluorescein isothiocyanate-conjugated anti-cytokeratin antibody AE1/AE3.


RESULTS
Cytokeratin-positive nodes were detected by means of flow cytometry within 40 minutes. Eight (8%) of the 100 lymph nodes from 4 (20%) of the 20 patients were deemed positive for metastasis on the basis of conventional histologic examination. By contrast, 33 (33%) lymph nodes from 13 (65%) patients were deemed positive on the basis of immunohistochemical cytokeratin staining, and 38 (38%) lymph nodes from 14 (70%) patients were deemed positive on the basis of flow cytometric cytokeratin-positive cell detection. All nodes deemed positive for metastasis on the basis of conventional and immunohistochemical methods were also positive on flow cytometry.


CONCLUSIONS
Flow cytometry enables rapid intraoperative diagnosis of nodal metastasis in patients with non-small cell lung cancer. Flow cytometric detection of cytokeratin-positive cells within lymph nodes correlates with their immunohistochemical detection, and its level of sensitivity is greater than that of conventional histologic staining and about equal to that of immunohistochemical staining.
Ito
Manabu
M
Akita University School of Medicine, Division of Thoracic Surgery, Department of Surgery, Akita City, Japan.
Minamiya
Yoshihiro
Y
Kawai
Hideki
H
Saito
Satoshi
S
Saito
Hajime
H
Imai
Kazuhiro
K
Ogawa
Jun-ichi
J
D014408:Biomarkers, Tumor / Q000032:analysis; D002289:Carcinoma, Non-Small-Cell Lung / Q000737:chemistry / Q000473:pathology / Q000556:secondary* / Q000601:surgery*; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D007432:Intraoperative Period; D007633:Keratins / Q000032:analysis; D008175:Lung Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000601:surgery*; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000737:chemistry* / Q000473:pathology; D008207:Lymphatic Metastasis
D014408:Biomarkers, Tumor; D007633:Keratins