Molecular Detection of Lymph Node Metastases in Breast Cancer Patients: Results of a Multicenter Trial Using the One-Step Nucleic Acid Amplification Assay

• Published in: Clinical cancer research 2009-04, Vol.15 (8), p.2879-2884
• Main Authors: Tamaki, Yasuhiro, Akiyama, Futoshi, Iwase, Takuji, Kaneko, Tomoyo, Tsuda, Hitoshi, Sato, Kazuhiko, Ueda, Shigeto, Mano, Masayuki, Masuda, Norikazu, Takeda, Masashi, Tsujimoto, Masahiko, Yoshidome, Katsuhide, Inaji, Hideo, Nakajima, Hiromu, Komoike, Yoshifumi, Kataoka, Tatsuki R, Nakamura, Seigo, Suzuki, Koyu, Tsugawa, Koichiro, Wakasa, Kenichi, Okino, Tsuyoshi, Kato, Yo, Noguchi, Shinzaburo, Matsuura, Nariaki
• Format: Article
• Language: English
• Subjects: breast; Breast - pathology; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Humans; Keratin-19 - genetics; Lymph Nodes - metabolism; Lymph Nodes - pathology; Lymphatic Metastasis; Middle Aged; OSNA; Reverse Transcriptase Polymerase Chain Reaction - methods; RNA, Messenger - analysis; RNA, Messenger - genetics; Sensitivity and Specificity; sentinel; Sentinel Lymph Node Biopsy
• ISSN: 1078-0432; 1557-3265
• DOI: 10.1158/1078-0432.CCR-08-1881

Purpose: Accurate assessment of metastasis in sentinel lymph nodes (SLN) of breast cancer is important but involves a heavy workload for the pathologist. We conducted a multicenter clinical trial in Japan to evaluate a new automated assay system for cytokeratin 19 mRNA, the one-step nucleic acid amplification (OSNA) assay (Sysmex), to detect lymph node metastasis of breast cancer. Experimental Design: Surgically obtained axillary lymph nodes were sectioned into four pieces, two of which were examined with the OSNA assay. The other two adjacent pieces were examined with H&E and immunohistochemical staining for cytokeratin 19. Serial sections at 0.2-mm intervals were used in trial 1 to determine the specificity of the OSNA assay, and three pairs of sections cut from the sliced surfaces of the pieces were used in trial 2 to compare the accuracy of the OSNA assay with that of a routine pathologic examination for SLNs in Japan. Results: In trial 1, the sensitivity and specificity were 95.0% [95% confidence interval (95% CI), 75.1-99.9%] and 97.1% (95% CI, 91.8-99.4%), respectively, for 124 axillary lymph nodes obtained from 34 patients. In trial 2, the agreement between findings of the assay and of the pathologic examination was 92.9% (95% CI, 90.1-95.1%) for 450 axillary lymph nodes obtained from 164 patients. Conclusion: The OSNA assay can detect lymph node metastasis as accurately as can conventional pathology and thus can be an effective addition to or alternative for rapid intraoperative examination of SLNs.