Whole sentinel lymph node analysis by a molecular assay predicts axillary node status in breast cancer

Background:

The one-step nucleic acid amplification (OSNA) assay is a rapid procedure for the detection of lymph node (LN) metastases using molecular biological techniques. The aim of this study was to assess the reliability of the whole sentinel lymph node (SLN) analysis by the OSNA assay as a predictor of non-SLN metastases.

Methods:

Consecutive 742 patients with breast cancer were enroled in the study. The association of non-SLN or ⩾4 LN metastases with clinicopathological variables was investigated using multivariate logistic analysis.

Results:

In total, 130 patients with a positive SLN who underwent complete axillary LN dissection were investigated. The frequency of non-SLN metastases in patients who were OSNA+ and ++ was 19.3% and 53.4%, respectively, and that in patients with ⩾4 LN metastases who were OSNA+ and ++ was 7.0% and 27.4%, respectively. The cytokeratin 19 (CK19) mRNA copy number (⩾5.0 × 10³; OSNA++) in the SLN was the most significant predictors of non-SLN metastases (P=0.003). The CK19 mRNA copy number (⩾1.0 × 10⁵) in the SLN was the only independent predictor of ⩾4 LN metastases (P=0.014).

Conclusion:

Whole SLN analysis using the OSNA assay could become a valuable method for predicting non-SLN and ⩾4 LN metastases.     

One-step nucleic acid amplification for intraoperative detection of lymph node metastasis in breast cancer patients.

PURPOSE: Detection of sentinel lymph node (SLN) metastasis in breast cancer patients has conventionally been determined by intraoperative histopathologic examination of frozen sections followed by definitive postoperative examination of permanent sections. The purpose of this study is to develop a more efficient method for intraoperative detection of lymph node metastasis. EXPERIMENTAL DESIGN: Cutoff values to distinguish macrometastasis, micrometastasis, and nonmetastasis were determined by measuring cytokeratin 19 (CK19) mRNA in histopathologically positive and negative lymph nodes using one-step nucleic acid amplification (OSNA). In an intraoperative clinical study involving six facilities, 325 lymph nodes (101 patients), including 81 SLNs, were divided into four blocks. Alternate blocks were used for the OSNA assay with CK19 mRNA, and the remaining blocks were used for H&E and CK19 immunohistochemistry-based three-level histopathologic examination. The results from the two methods were then compared. RESULTS: We established CK19 mRNA cutoff values of 2.5 x 10(2) and 5 x 10(3) copies/muL. In the clinical study, an overall concordance rate between the OSNA assay and the three-level histopathology was 98.2%. Similar results were obtained with 81 SLNs. The OSNA assay discriminated macrometastasis from micrometastasis. No false positive was observed in the OSNA assay of 144 histopathologically negative lymph nodes from pN0 patients, indicating an extremely low false positive for the OSNA assay. CONCLUSION: The OSNA assay of half of a lymph node provided results similar to those of three-level histopathology. Clinical results indicate that the OSNA assay provides a useful intraoperative detection method of lymph node metastasis in breast cancer patients.     

Sentinel lymph node biopsy after neoadjuvant chemotherapy predicts pathological axillary lymph node status in breast cancer patients with clinically positive axillary lymph nodes at presentation

Background

It is still controversial whether axillary lymph node (ALN) dissection (ALND) can be omitted after negative sentinel lymph node (SLN) biopsy (SLNB) in breast cancer (BC) patients with clinically positive ALNs at presentation treated with neoadjuvant chemotherapy (NAC). The study aim was to analyze whether SLNB could be useful in these patients.

Methods

In a retrospective study, eligible patients were women with invasive BC with clinically positive ALNs at presentation, treated with NAC then a total or partial mastectomy, with an intraoperative histological examination of SLNs and non-SLNs suspicious for metastasis followed by ALND. Non-SLNs suspicious for metastasis were defined as hard or large nodes located in the same level of the axilla where clinically positive ALNs had been initially identified. The results of SLNB and clinicopathological characteristics were analyzed for correlation with pathological ALN status.

Results

In a consecutive series of 105 women with 107 BC cases, 81 (75.7 %) had at least 1 SLN, and the remaining 26 (24.3 %) had at least 1 non-SLN suspicious for metastasis. The intraoperative (or final) histological examination of these nodes revealed that the false-negative (FN) rate and accuracy were 8.2 (or 6.3) % and 95.1 (or 96.3) %, respectively. Estrogen receptor status at presentation, pathological tumor response, lymphovascular invasion after NAC, and NAC regimen were correlated with pathological ALN status.

Conclusion

The histological examination of SLNs and that of non-SLNs suspicious for metastasis are useful for predicting pathological ALN status in BC patients with clinically positive ALNs at presentation who are treated with NAC.     

One-step nucleic acid amplification (OSNA) assay for detecting lymph node metastasis in cervical and endometrial cancer: a preliminary study

ObjectiveTo evaluate the accuracy of the one-step nucleic acid amplification (OSNA) assay for the diagnosis of lymph node (LN) metastasis in uterine cancer.MethodsA total of 116 LNs from 30 patients with cervical and endometrial cancer, enrolled in this prospective study, were used. Excised LNs were cut into 4 to 6 blocks at 2 mm intervals, and nonadjacent blocks were alternately subjected to either histological examination or the OSNA assay.ResultsThe concordance rate between histological examination and the OSNA assay in cervical cancer and in endometrial cancer was 95.9% and 95.2%, respectively. The sensitivity, specificity, and negative predictive value of the OSNA assay were 80%, 97.7%, and 97.7% in cervical cancer, and 85.7%, 93.3%, and 98.2% in endometrial cancer, respectively. In cervical cancer, discordant results were observed in 2 out of 49 LNs (4.1%); 1 was OSNA assay-positive and histological examination-negative, and 1 was OSNA assay-negative and histological examination-positive. In endometrial cancer, discordant results were observed in 5 out of 67 LNs (7.5%); 4 were OSNA assay-positive and histological examination-negative, and 1 was OSNA assay-negative and histological examination-positive.ConclusionThe OSNA assay showed high concordance rate with histological examination, sensitivity, and specificity in uterine cancer, suggesting that it could enhance the accuracy of conventional pathological examination for the detection of LN metastasis by reducing false negative rate.     

Basal breast cancer molecular subtype predicts for lower incidence of axillary lymph node metastases in primary breast cancer

BACKGROUND: Axillary lymph node involvement remains the most important prognostic factor in early-stage breast cancer. We hypothesized that molecular classification based on breast cancer biology would predict the presence of nodal involvement at diagnosis, which might aid treatment decisions regarding the axilla. PATIENTS AND METHODS: From a clinically annotated tissue microarray of 4444 early-stage breast cancers, expression of estrogen receptor (ER), progesterone receptor (PgR), HER2, epidermal growth factor receptor, and cytokeratin 5/6 was determined by immunohistochemistry. Cases were classified by published criteria into molecular subtypes of luminal, luminal/HER2 positive, HER2 positive/ER negative/PgR negative, and basal. Risk of axillary nodal involvement at diagnosis was determined in 2 multivariable logistic regression models: a "core biopsy model" including molecular subtype, age, grade, and tumor size and a "lumpectomy model," which also included lymphovascular invasion. Luminal was used as the reference group. After internal validation of findings in 2 independent sets, we conducted combined analysis of both. RESULTS: In the core biopsy model, the molecular subtypes had a predictive effect for nodal involvement (P= .000001), with the basal subtype having an odds ratio for axillary lymph node involvement of 0.53 (95% CI, 0.41-0.69). Tumor grade (P=5.43 x 10(-12)) and size (P=8.52 x 10(-35)) were also predictive for nodal involvement. Similar results were found in the lumpectomy model, where lymphovascular invasion was also predictive (P=2.74 x 10(-115)). CONCLUSION: These results indicate that the basal breast cancer molecular subtype predicts a lower incidence of axillary nodal involvement, and including biomarker profiles to predict nodal status at diagnosis could help stratification for decisions regarding axillary surgery and locoregional radiation.     

Percent positive axillary lymph node metastasis predicts survival in patients with non-metastatic breast cancer

PURPOSE: We retrospectively evaluated the impact of percent positive axillary nodal involvement on the therapeutic outcomes in patients with non-metastatic breast cancer receiving postmastectomy radiotherapy and chemotherapy. MATERIALS AND METHODS: Between January 1994 and December 2002, the medical records of 939 eligible non metastatic breast carcinoma patients were analyzed. Chest wall radiotherapy was indicated in case of positive surgical margin, tumor size equal or more than 4 cm, skin-fascia invasion. Lymphatic irradiation was applied for more than three metastatic axillary lymph nodes, incomplete axillary dissection (<10 lymph nodes), extracapsular extension or perinodal fat tissue invasion. A total dose of 50 Gy was given to chest wall and lymph node regions with 2 Gy daily fractions. Statistical analyses were performed by Kaplan-Meier method, Log-rank test and Cox's regression analysis. RESULTS: The median follow-up for all patients alive was 62 months. The 5-year overall survival (OS) and disease-free survival (DFS) for entire cohort were 81%, and 65%, respectively. Univariate analysis for OS revealed significance for tumour size (< or =5 cm vs. >5 cm, p<0.001), metastatic nodal involvement (0 vs. 1-3 vs. >4 LN, p<0.001), percent positive nodal involvement ([metastatic nodes/total nodes removed] x 100; 0 vs. < or =25% vs. 26-50% vs. >50%, p<0.001), surgical margin status (negative vs. positive, p=0.05), and hormonal treatment (present vs. absent, p=0.03). DFS had similarly significance for age (< or =40 years vs. >40 years, p=0.006), tumour size (0.02), metastatic nodal involvement (p<0.001), percent positive nodal involvement (p<0.001), and perinodal invasion (present vs. absent, p=0.01). Multivariate analysis revealed significance for tumour size, percent positive nodal involvement, hormonal treatment, and surgical margin status for OS. Age and percent positive nodal involvement were found to be significant for DFS. CONCLUSION: Percent positive nodal involvement was found to be a significant prognostic factor for survival in all end-points.     

Proteomic profiling of primary breast cancer predicts axillary lymph node metastasis

To determine if protein expression in primary breast cancers can predict axillary lymph node (ALN) metastasis, we assessed differences in protein expression between primary breast cancers with and without ALN metastasis using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Laser capture microdissection was performed on invasive breast cancer frozen sections from 65 patients undergoing resection with sentinel lymph node (SLN) or level I and II ALN dissection. Isolated proteins from these tumors were applied to immobilized metal affinity capture (IMAC-3) ProteinChip arrays and analyzed by SELDI-TOF-MS to generate unique protein profiles. Correlations between unique protein peaks and histologically confirmed ALN status and other known clinicopathologic factors were examined using ANOVA and multivariate logistic regression. Two metal-binding polypeptides at 4,871 and 8,596 Da were identified as significant risk factors for nodal metastasis (P = 0.034 and 0.015, respectively) in a multivariate analysis. Lymphovascular invasion (LVI) was the only clinicopathologic factor predictive of ALN metastasis (P = 0.0038). In a logistic regression model combining the 4,871 and 8,596 Da peaks with LVI, the area under the receiver operating characteristic curve was 0.87. Compared with patients with negative ALN, those with > or =2 positive ALN or non-SLN metastases were significantly more likely to have an increased peak at 4,871 Da (P = 0.016 and 0.0083, respectively). ProteinChip array analysis identified differential protein peaks in primary breast cancers that predict the presence and number of ALN metastases and non-SLN status.     

Intraoperative molecular assay for sentinel lymph node metastases in early stage breast cancer: a comparative analysis between one-step nucleic acid amplification whole node assay and routine frozen section histology

BACKGROUND:

Conventional histopathological examination is limited in measuring accurate total metastatic volume in a lymph node. Recently, a molecular‐based procedure to detect lymph node metastases, one‐step nucleic acid amplification (OSNA) assay, has been developed. OSNA assay can assess a whole lymph node and yields semiquantitative results. The authors compared the performance in intraoperative detection of sentinel lymph node metastases with OSNA assay using a whole lymph node versus routine frozen section (FS) histology with a 2 mm‐sectioned lymph node.

METHODS:

Subjects comprised 531 consecutive patients diagnosed with OSNA assay and 618 consecutive patients diagnosed with FS histological examination. The authors compared the sentinel lymph node‐positive rate between the OSNA and FS cohorts, and investigated characteristics of patients for whom OSNA could detect metastases but FS could not. OSNA (+) was defined as micrometastasis, and OSNA (++) and (+I) were defined as macrometastasis.

RESULTS:

OSNA assay detected more cases of sentinel lymph node metastases than FS histology (OSNA 121 of 531, 22.8% vs FS 109 of 618, 17.6%; P = .036), particularly micrometastases (46 of 531, 8.7% vs 28 of 618, 4.5%; P = .0064). There was no difference in macrometastasis detection between OSNA and FS (75 of 531, 14.1% vs 81 of 618, 13.1%; P = .68). OSNA detected more metastases than FS in postmenopausal patients (77 of 302, 25.5% vs 43 of 351, 12.3%; P < .0001), and in tumors without fat invasion (23 of 156, 14.7% vs 6 of 151, 4.0%; P = .012) or lymphovascular invasion (67 of 395, 17.0% vs 45 of 458, 9.8%; P = .042).

CONCLUSIONS:

Intraoperative OSNA assay detects more sentinel lymph node metastases, particularly micrometastases, than does FS histology. OSNA assay can also detect more metastases in postmenopausal patients or from less aggressive primary tumors compared with FS histology. Cancer 2011. © 2011 American Cancer Society.     

Evaluation of axillary lymph node status in breast cancer with MRI

Background  We performed a retrospective study to establish the optimal radiological criteria for axillary lymph node metastases from breast cancer by measuring all dissected nodes, and to determine whether magnetic resonance imaging (MRI) could reliably reveal axillary involvement. Methods  Pathological findings and MRI scans of 202 patients with invasive breast cancer were re-viewed. The long- and short-axis dimensions of all level I and II lymph nodes were measured micro-scopically, and then the long-to-short axis (L/S) ratio of each node was calculated. These parameters were compared with pathological nodal status to define radiological criteria for axillary involvement. MRI was carried out using T1-weighted spin-eho sequences in the coronal and sagittal planes. On MRI, every detected lymph node was measured and the shape of the nodal cortex was also examined. Then the diagnostic ability of MRI was assessed using these morphologic criteria. Results  On histopathological examinations of 4043 dissected lymph nodes, a long-axis dimension of 10 mm or larger combined with a long-to-short axis ratio of less than 1.6 was the most accurate criteria for predicting lymph node metastases. On MRI, eccentric cortical hypertrophy was seen in only metas-tatic axillae. When these morphologic features were used as criteria for malignancy, MRI had a sensi-tivity of 79%, a specificity of 93%, and an accuracy of 88%. In 16 of 17 false-negative axillae, MRI showed normally sized lymph nodes (<10 mm). Conclusion  Our study indicates that MRI is a useful diagnostic method for the evaluation of axillary nodal status, but is limited in the detection of small metastatic lymph nodes.     

Sentinel lymph node analysis in breast cancer: contribution of one-step nucleic acid amplification (OSNA)

One-step nucleic acid amplification (OSNA, Sysmex, Kobe, Japan) offers an excellent opportunity for accurate exhaustive sentinel lymph node (SLN) examination in breast cancer patients. Calibrated with conventional postoperative histology, this molecular technique yields comparable results intraoperatively, expressed as micrometastasis, macrometastasis or no metastasis depending on the CK19 mRNA copy number amplified in SLN lysates. We applied OSNA to detect metastasis in 810 SLNs from 367 patients with early stage breast cancer. We compared the rate of OSNA-positive SLNs in patients with invasive breast cancer (< 2 cm) versus the rate observed in a historical cohort using conventional histological examination of SLNs. No significant difference was observed, the OSNA assay was positive in 24.4% of patients, compared with positive histology in 24.8% in the historical cohort if including patients with isolated tumour cell (ITC) and in 23.4% excluding them. Opportunities for optimised patient management using OSNA are discussed: intraoperative detection of OSNA-positive SLNs enables axillary lymph node dissection (ALND) during the same procedure; standard OSNA techniques enable the establishment of homogeneous groups based on examination of whole SLNs for valid comparisons between different centres.     

IV-DSA is a new diagnostic tool for axillary lymph node metastasis in breast cancer patients

BACKGROUND AND OBJECTIVE: The aim of this study is to know whether intravenous digital subtraction angiography (IV-DSA) is useful to detect axillary lymph node metastasis of breast cancer and to evaluate the anigiogenesis of lymph nodes in the axilla. PATIENTS AND METHODS: Forty three primary breast cancer patients (N0: 26 cases, N1: 5 cases, N2: 2 cases) who underwent IV-DSA between January and November 2000 were included in the study. Infinix CB apparatus (Toshiba, Japan) was used to collect IV-DSA images and when a mass became stained in the axilla, it was considered to be metastatic. The angiogenesis was studied by examining microvessel density (MVD) after lymph node immunostaining for factor VIII. Primary tumor was detected by IV-DSA in all 43 cases. RESULTS: Axillary lymph node metastases were detected by IV-DSA in 34.9% of cases (15/43), and by pathology in 37.2% (16/43). The sensitivity, specificity, and accuracy of the diagnostic method were 75.0% (12/16), 88.9% (24/27), and 83.7% (36/43), respectively. MVD, calculated after immunostaining for factor VIII, was significantly lower in the in metastatic region of lymph nodes identified by DSA (88.5 +/- 35.0) than in metastasis-free lymph nodes (141.1 +/- 34.0, P < 0.0001). CONCLUSIONS: IV-DSA is useful in the diagnosis of axillary lymph node metastasis of breast cancer. Our results suggest that the primary factors involved in the mechanism of DSA display may be different from high/low MVC values.     

Primary tumour characteristics and axillary lymph node status in breast cancer.

This paper examines the correlation between axillary lymph node status and primary tumour characteristics in breast cancer and whether this can be used to select patients for axillary lymphadenectomy. The results are based on a retrospective analysis of 909 patients who underwent axillary dissection in our unit. Axillary lymph nodes containing metastases were found in 406 patients (44.7%), all with invasive carcinomas, but in none of the 37 carcinomas-in-situ. Nodal status was negative in all T1a tumours, but lymph node metastases were present in 16.3% and 35.7% of T1b and T1c tumours respectively. When histological grade was taken into account, positivity for grade I T1b and T1c tumours fell to 13.6% and 26.7% respectively. Lymph node metastases were found in 85% of patients with lymphovascular invasion in their tumours as compared to only 15.4% of those without and in 45.5% of oestrogen and progesterone receptor-positive tumours. When one or both hormone receptors were absent this figure was much higher. It appears that for T1a breast cancers axillary dissection is not necessary, whereas for T1b, T1c and grade I T2 tumours other histopathological parameters should be taken into consideration in deciding who should undergo axillary lymphadenectomy.     

Diagnosis of axillary lymph node metastases in patients with breast cancer

Summary The diagnosis of axillary (AX) metastases remains a challenge in the management of breast cancer and is a subject of controversy. Clinical node staging clearly is limited in the assessment of AX lymph nodes. AX mammography, ultrasonography, and computed tomography (CT) do not provide histologic information. Although nuclear magnetic resonance imaging may have considerable value in the diagnosis of AX metastases, it does not detect micrometastases. The use of biologic markers in the assessment of AX metastases remains a subject of investigation. On the other hand, biopsy of selected AX nodes or tissue with examination of histology or cytology generally would not identify a significant percentage of patients with AX node involvement. Sentinel lymph node biopsy, however, might be potentially useful for assessing AX metastases, although it remains investigational. In order to simplify diagnosis and reduce morbidity and mortality, alternatives to AX dissection must be sought and imaging and staging modalities refined. We present a review of the literature pertaining to the diagnosis of AX metastases in patients with breast cancer and a discussion of some current areas of controversy.     

Molecular detection of lymph node metastasis in breast cancer patients treated with preoperative systemic chemotherapy: a prospective multicentre trial using the one-step nucleic acid amplification assay

Background:

For patients with breast cancer treated with preoperative chemotherapy, residual tumour burden in lymph nodes is the strongest prognostic factor. However, conventional pathological examination has limitations that hinder the accurate and reproducible measurement. The one-step nucleic acid amplification (OSNA) assay is a novel molecular method for detecting nodal metastasis. In this prospective multicentre trial, we assessed the performance of the OSNA assay in detecting nodal metastasis after chemotherapy.

Methods:

In total, 302 lymph nodes from 80 breast cancer patients who underwent axillary dissection after chemotherapy were analysed. Each node was cut into two or four slices. One piece or alternate pieces were evaluated by pathology, and the other(s) were examined using the OSNA assay. The results of the two methods were compared. Stromal fibrosis, histiocytic aggregates, and degenerated cancer cells were regarded as chemotherapy-induced histological changes.

Results:

The overall accuracy, sensitivity, and specificity of the OSNA assay compared with the reference pathology were 91.1%, 88.3%, and 91.7%, respectively. Of the 302 lymph nodes, 66 (21.9%) exhibited chemotherapy-induced histology. For these nodes, the accuracy, sensitivity, and specificity were 90.9%, 88.9%, and 93.3%, respectively.

Conclusion:

The OSNA assay can detect the residual tumour burden as accurately as conventional pathology, although chemotherapy-induced histological changes are present.