Accurate staging of axillary lymph nodes from breast cancer patients using a novel molecular method

• Published in: British journal of cancer Vol. 105; no. 8; pp. 1197 - 1202
• Main Authors: Osako, T, Iwase, T, Kimura, K, Yamashita, K, Horii, R, Akiyama, F
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 11-10-2011; Nature Publishing Group
• Subjects: 631/1647/1407/1555; 692/699/67/1347; 692/699/67/322; 692/700/139/1677; Adult; Aged; Aged, 80 and over; Axilla; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Biopsy; Breast cancer; Breast Neoplasms - pathology; Cancer Research; Cancer therapies; Cohort Studies; Dissection; Drug Resistance; Epidemiology; Female; Gynecology. Andrology. Obstetrics; Histology; Humans; Lymphatic Metastasis - pathology; Lymphatic system; Mammary gland diseases; Medical prognosis; Medical research; Medical sciences; Metastasis; Middle Aged; Molecular Diagnostics; Molecular Medicine; Oncology; Pathology; Sentinel Lymph Node Biopsy - methods; Tumors; Japan; sentinel node biopsy; breast cancer; histopathological examination; micrometastasis; non-sentinel lymph node metastasis; one-step nucleic acid amplification assay; Human; histopathological examination; Breast disease; Lymph node; Staging; Sentinel lymph node metastasis; Stage classification; Malignant lymphadenopathy; Malignant hemopathy; Breast cancer; Malignant tumor; Method; Mammary gland diseases; Anatomic pathology; Cancerology; Histopathology; Biopsy; Axillary ganglion; Micrometastasis; One-step nucleic acid amplification; Cancer
• ISSN: 0007-0920; 1532-1827
• DOI: 10.1038/bjc.2011.350

Background:
The one-step nucleic acid amplification (OSNA) assay is a molecular-based lymph-node metastasis detection procedure that can assess a whole node and yields semi-quantitative results for the detection of clinically relevant nodal metastases. We aimed to determine the performance of the OSNA assay as an accurate nodal staging tool in comparison with routine histological examination.
Methods:
Subjects comprised 183 consecutive patients with pT1-2 breast cancer who underwent axillary dissection after positive sentinel-node (SN) biopsy with the OSNA assay. Of these, for non-SN evaluation, 119 patients underwent OSNA assay evaluation, whereas 64 had single-section histology. We compared the detection rates of non-SN metastasis and upstaging rates from the SN stage according to the American Joint Committee on Cancer staging between the OSNA and histology cohorts.
Results:
OSNA detected more cases of non-SN metastases than histology (OSNA 66/119, 55.5%
vs
histology 13/64, 20.3%;
P
<0.001), particularly micrometastases (36/119, 30.3%
vs
1/64, 1.6%;
P
<0.001). Total upstaging rates were similar in both cohorts (20/119, 16.8%
vs
9/64, 14.1%,
P
=0.79).
Conclusion:
OSNA detects a far greater proportion of non-SN micrometastases than routine histological examination. However, upstaging rates after axillary dissection were not significantly different between both cohorts. Follow-up of the OSNA cohort is required to determine its clinical relevance.