Identification and biologic significance of micrometastases in axillary lymph nodes in patients with invasive breast cancer

A Biomimetic Hyaluronic Acid Hydrogel Models Mass Dormancy in Brain Metastatic Breast Cancer Spheroids

Approximately 90% of breast cancer related mortalities are due to metastasis to distant organs. At the metastatic sites, cancer cells are capable of evading death by exhibiting cellular or mass dormancy. However, the mechanisms involved in attaining dormancy at the metastatic site are not well understood. This is partly due to the lack of experimental models to study metastatic site-specific interactions, particularly in the context of brain metastatic breast cancer (BMBC). Herein, an in vitro hyaluronic acid (HA) hydrogel-based model is developed to study mass dormancy in BMBC. HA hydrogels with a stiffness of ≈0.4 kPa are utilized to mimic the brain extracellular matrix. MDA-MB-231Br or BT474Br3 BMBC spheroids are prepared and cultured on top of HA hydrogels or in suspension for 7 days. HA hydrogel induced a near mass dormant state in spheroids by achieving a balance between proliferating and dead cells. In contrast, these spheroids displayed growth in suspension cultures. The ratio of %p-ERK to %p-p38 positive cells is significantly lower in HA hydrogels compared to suspension cultures. Further, it is demonstrated that hydrogel induced mass dormant state is reversible. Overall, such models provide useful tools to study dormancy in BMBC and could be employed for drug screening.

Thorny ground, rocky soil: Tissue-specific mechanisms of tumor dormancy and relapse

Disseminated tumor cells (DTCs) spread systemically yet distinct patterns of metastasis indicate a range of tissue susceptibility to metastatic colonization. Distinctions between permissive and suppressive tissues are still being elucidated at cellular and molecular levels. Although there is a growing appreciation for the role of the microenvironment in regulating metastatic success, we have a limited understanding of how diverse tissues regulate DTC dormancy, the state of reversible quiescence and subsequent awakening thought to contribute to delayed relapse. Several themes of microenvironmental regulation of dormancy are beginning to emerge, including vascular association, co-option of pre-existing niches, metabolic adaptation, and immune evasion, with tissue-specific nuances. Conversely, DTC awakening is often associated with injury or inflammation-induced activation of the stroma, promoting a proliferative environment with DTCs following suit. We review what is known about tissue-specific regulation of tumor dormancy on a tissue-by-tissue basis, profiling major metastatic organs including the bone, lung, brain, liver, and lymph node. An aerial view of the barriers to metastatic growth may reveal common targets and dependencies to inform the therapeutic prevention of relapse.

Sentinel lymph nodes for breast carcinoma: an update on current practice

Sentinel lymph node (SLN) biopsy has been established as the standard of care for axillary staging in patients with invasive breast carcinoma and clinically negative lymph nodes (cN0). Historically, all patients with a positive SLN underwent axillary lymph node dissection (ALND). The ACOSOG Z0011 trial showed that women with T1-T2 disease and cN0 who undergo breast-conserving surgery and whole-breast radiotherapy can safely avoid ALND. The main goal of SLN examination should be to detect all macrometastases (>2 mm). Gross sectioning of SLNs at 2-mm intervals and microscopic examination of one haematoxylin and eosin-stained section from each SLN block is the preferred method for pathological evaluation of SLNs. The role and timing of SLN biopsy for patients who have received neoadjuvant chemotherapy is controversial, and continues to be explored in clinical trials. SLN biopsies from patients with invasive breast carcinoma who have received neoadjuvant chemotherapy pose particular challenges for pathologists.

Prognostic role of micrometastases in sentinel lymph node in patients with invasive breast cancer

BACKGROUND AND PURPOSE OF THE STUDY

Axillary lymph node status at the time of diagnosis remains one of the most important prognostic factors in women with breast cancer. Sentinel lymph node biopsy (SLNB) proved to be a reliable method for the evaluation of axillary nodal status in early-stage invasive breast cancer. The prognostic value and potential therapeutic consequences of SLN micrometastases remains a matter of great debate.

PATIENTS AND METHODS

From January 1998 to March 2011, 1,976 consecutive patients with non-metastatic invasive breast cancer underwent surgical treatment; 1,080 of them (54.6%) underwent SLNB. We collected data regarding demography, preoperative lymphoscintigraphy, type of surgery, histopathologic and immunohistochemical features and adjuvant treatment.

MAIN FINDINGS

A mean number of 2.1 ± 1.4 (range 1-13) SLN per patient were collected, a total of 2,294 nodes. SLNs were macrometastatic in 16.7% of patients and micrometastatic in 3.3%. Among the patients with positive SLN 93.6% underwent complete ALND. The overall survival (OS) and disease-free survival (DFS) of 72 patients with micrometastases in SLN at 60 months was 100%, similar to patients with negative SLN (98.7%), quite different from the DFS of N1-N3 patients (85.8%). Statistically significant differences in OS and DFS were observed between patients with N1mi and the group with N1-N3 sentinel node (p < 0.001 and p = 0.04) and also between patients with negative SLN and those with macrometastatic SLN (p < 0.001 for both).

CONCLUSION

SLN micrometastases could represents an epiphenomenon of peritumoral lymphovascular invasion which impacts independently on the survival of patients with invasive breast cancer.

The prognostic value of the metastatic lymph node ratio and maximal metastatic tumor size in pathological N1a papillary thyroid carcinoma

OBJECTIVE

The presence of central neck lymph node (LN) metastases (defined as pN1a according to Tumor Node Metastasis classification) in papillary thyroid cancer (PTC) is known as an independent risk factor for recurrence. Extent of LN metastasis and the completeness of removal of metastatic LN must have an impact on prognosis but they are not easy to measure. Moreover, the significance of the size of metastatic tumors in LNs has not been clarified. This study was to evaluate the impact of the extent of LN metastasis and size of metastatic tumors on the recurrence in pathological N1a PTC.

DESIGN

This retrospective observational cohort study enrolled 292 PTC patients who underwent total thyroidectomy with central neck dissection from 1999 to 2005. LN ratio was defined as the number of metastatic LNs divided by the number of removed LNs, which was regarded as variable reflecting both extent of LN metastasis and completeness of resection, and LN size as the maximal diameter of tumor in metastatic LN.

RESULTS

The significant risk factors for recurrence in univariate analysis were large primary tumor size (defined as larger than 2 cm), high LN ratio (defined as higher than 0.4), and presence of macrometastasis (defined as larger than 0.2 cm). Age, sex, clinical node status, and microscopic perithyroidal extension had no effect on recurrence. In multivariate analysis, high LN ratio and presence of macrometastasis were independent risk factors for recurrence.

CONCLUSION

LN ratio and size of metastatic nodes had a significant prognostic value in pathological N1a PTC. We suggest that risk stratification of pathological N1a PTC according to the pattern of LN metastasis such as LN ratio and size would give valuable information to clinicians.

Development of a novel metastatic breast cancer score based on hyaluronic acid metabolism

Tumor metastasis involves the dissemination of malignant cells into the basement membrane, and the vascular system contributes to the circulating pool of these markers. In this context, our aim has been focused on the development of a non-invasive score based on degradation of the backbone of glycosaminoglycans of the extracellular matrix; namely hyaluronic acid (HA), for the assessment of metastasis in patients with breast cancer. HA level was determined by enzyme-linked immunosorbent assay; CA 15.3 was determined by microparticle enzyme immunoassay; hyaluronidase, N-acetyl-β-D-glucosaminidase, β-glucuronidase, glucuronic acid, and glucosamine were assayed by standard colorimetric techniques in 217 patients with breast cancer. Statistical analyses were performed by logistic regression and receiver-operating characteristic analysis curves. The multivariate discriminant analysis selects a score based on absolute values of the six biochemical markers: metastatic breast cancer score (MBCS) = [1.04 (Numerical constant) + 0.003 × CA 15.3 (U/l) + 0.001 × HA (ng/ml) + 0.004 × hyaluronidase (mg N-acetyl-β-D-glucosamine/ml/18 h) + 0.001 × N-acetyl-β-D-glucosaminidase (μmol/ml/min) + 0.026 × glucuronic acid (ng/ml) + 0.003 × glucosamine (μg/dl)]. This function correctly classified 87 % of metastatic breast cancer at cut-off value = 0.85 (i.e., great than 0.85 indicates patients with metastatic breast cancer and less than 0.85 indicates patients with non-metastatic breast cancer). MBCS is a novel, non-invasive, and simple score which can be applied to discriminate patients with metastatic breast cancer.

Reliability of frozen section in breast sentinel lymph node examination

OBJECTIVES

Sentinel lymph node (SLN) examination in breast carcinoma is crucial to spare patients unnecessary lymph node (LN) dissection. The specificity and accuracy of SLN examination by frozen section has been variable in many studies. This study aims to describe our experience in frozen section (FS) analysis of SLN.

METHODS

We have retrospectively analyzed data from 449 axillary SLN subjected to FS examination from 440 patients with breast cancer. All patients had free axillary LN clinically.

RESULTS

Out of 449 cases, no false positive cases were found on FS (specificity of 100 %). Twenty-six cases were false negative (6 interpretation-related reasons and 20 technical-related reasons). The overall sensitivity was 84 % with a total accuracy rate of 93 % and interpretation sensitivity of 96 %. Three cases were deferred. Twenty-two of the false negative cases were micrometastases, whereas 4 were macrometastases. The interpretation-related false negative cases were not related to the subtype of carcinoma (ductal vs. lobular). However, they were all of low nuclear grade.

CONCLUSION

These findings are similar to most published data. FS is a reliable method for evaluating SLN. The most common cause of false negative diagnosis is sampling error. More attention should be paid to low-grade tumors. Moreover, in FS analysis, we recommend to totally submit SLNs that are less than 5 mm in diameter, bisecting them if possible, and to serially section SLNs that are at least 5 mm at 2-mm intervals.

Remote frozen section examination of breast sentinel lymph nodes by telepathology

BACKGROUND

Intraoperative sentinel lymph node (SLN) examination during breast cancer surgery guides the need for immediate axillary clearance. This may be difficult to implement when surgery is performed distant to the centres where pathological examination is undertaken. We aimed to implement and validate a telepathology service for the remote examination of breast SLN by frozen section (FS).

METHODS

We tested an Internet-based remote microscopy system to report intraoperative FS in real time from two district hospitals without on-site anatomical pathology services.

RESULTS

FS was performed remotely on 52 patients. Seventeen out of 52 patients had metastases, of which there were six false-negative diagnoses comprising four of micrometastatic disease and two of isolated tumour cells (ITCs). There were no false-negative diagnoses for macrometastatic disease and no false-positive diagnoses. As a control, we audited our experience with 239 consecutive SLN FS examined by on-site pathologists. Sixty out of 239 patients had metastases, of which there were 24 false-negative diagnoses comprising 12 cases of ITC, 5 of micrometastases and 7 of macrometastases. The accuracy of remote FS was equivalent to that of in-house FS (88.2% versus 89.9%).

CONCLUSION

Remote FS for breast SLN is an accurate procedure ,which is not inferior to FS performed on site.

The sensitivity and specificity of sentinel lymph node biopsy for breast cancer at Baylor University Medical Center at Dallas: a retrospective review of 488 cases

Sentinel lymph node (SLN) biopsy has become the standard of care for breast carcinoma management, as it precludes the negative morbid effects-including decreased shoulder range of motion, lymphedema, and paresthesias-of unnecessary axillary lymph node dissection. However, the method of pathologic evaluation of the lymph node has been scrutinized to obtain the greatest sensitivity, specificity, and negative predictive value, ultimately for the benefit of the patient. This retrospective study analyzed 488 biopsies completed by two surgeons and read by multiple pathologists affiliated with Pathologists Biomedical Laboratories. When metastatic disease was not grossly obvious, analysis of the SLN began with touch imprint cytology and, if necessary, a frozen section analysis. On the subsequent day, three levels of the SLN were analyzed with hematoxylin and eosin stain and immunohistochemistry with cytokeratin AE1-3 and the appropriate control. Touch imprint cytology and/or frozen section analysis (where applicable) correctly identified 78 of 89 macrometastases, with a sensitivity of 88%, specificity of 100%, and negative predictive value of 97%. Sensitivity was 72% for micrometastases and 60% for isolated tumor cells, each with 100% specificity. In conclusion, the sensitivity and specificity of SLN biopsy at our institution compares with the higher end of percentages reported in the literature.

Breast cancer screening in the Czech Republic: time trends in performance indicators during the first seven years of the organised programme

Background

The Czech Breast Cancer Screening Programme (CBCSP) was initiated in September 2002 by establishing a network of accredited centres. The aim of this article is to describe progress in the programme quality over time after the inception of the organised programme.

Methods

The CBCSP is monitored using an information system consisting of three principal components: 1) the national cancer registry, 2) a screening registry collecting data on all screening examinations, further assessments and final diagnoses at accredited programme centres, and 3) administrative databases of healthcare payers. Key performance indicators from the European Guidelines have been adopted for continuous monitoring.

Results

Breast cancer incidence in the Czech Republic has steadily been increasing, however with a growing proportion of less advanced stages. The mortality rate has recently stabilised. The screening registry includes 2,083,285 records on screening episodes between 2002 and 2008. In 2007-2008, 51% of eligible women aged 45-69 were screened. In 2008, the detection rates were 6.1 and 3.7 per 1,000 women in initial and subsequent screening respectively. Corresponding recall rates are 3.9% and 2.2%, however, it is necessary to pay attention to further assessment performed during the screening visits. Benign to malignant open biopsy ratio was 0.1. Of invasive cases detected in screening, 35.6% was less than 10 mm in diameter. Values of early performance indicators, as measured by both crude and standardized estimates, are generally improving and fulfil desirable targets set by European Guidelines.

Conclusions

Mammography screening in the Czech Republic underwent successful transformation from opportunistic prevention to an organised programme. Values of early indicators confirm continuous improvement in different aspects of process quality. Further stimulation of participation through invitation system is necessary to exploit the full potential of screening mammography at the population level.

Axillary lymph node dissection in early-stage invasive breast cancer: is it still standard today?

Evaluation of axillary lymph node status by sentinel lymph node biopsy (SLNB) and complete axillary lymph node dissection (ALND) are an inherent part of breast cancer treatment. Increased understanding of tumor biology has changed the prognostic and therapeutic impact of lymph node status. Non-invasive imaging techniques like axillary ultrasound, FDG-PET, or MRI revealed moderate sensitivity and high specificity in evaluation of lymph node status. Therefore, they are not sufficient for lymph node staging. Otherwise, the impact of remaining micrometastases and even macrometastases for prognosis and treatment decisions is overestimated. Considering tumor biology, the distinction of axillary metastases in isolated tumor cells (ITC, pN0(i+)); micrometastases (pN1mi), and macrometastases (pN1a) is not comprehensible. Increasing data support the thesis that remaining axillary metastases neither increase the axillary recurrence rate nor decrease overall survival. It is doubtful that axillary tumor cells are capable to complete the complex multistep metastatic process. If applied, axillary metastases are sensitive to systemic treatment and are targeted by postoperative tangential breast irradiation. Therefore, the controversy about the clinical relevance of tumor cell clusters or micrometastases in SLN is a sophisticated but not contemporary discussion. Currently, there is no indication for axillary surgery in elderly patients with favorable tumors and clinically tumor-free lymph nodes. Nonetheless, a rational and evidence-based approach to the management of clinically and sonographically N0 patients with planned breast-conserving surgery and limited tumor size is needed now.

Tumor suppressor genes are frequently methylated in lymph node metastases of breast cancers

INTRODUCTION

Metastasis represents a major adverse step in the progression of breast carcinoma. Lymph node invasion is the most relevant prognostic factor; however little is known on the molecular events associated with lymph node metastasis process. This study is to investigate the status and role of methylation in lymph node metastatic tumors.

MATERIALS AND METHODS

Bisulfite pyrosequencing is used to screen 6 putative tumor suppressor genes (HIN-1, RASSF1A, RIL, CDH13, RARbeta2 and E-cadherin) in 38 pairs of primary breast tumors and lymph node metastases.

RESULTS

We found that HIN-1, CDH13, RIL, RASSF1A and RARbeta2 were frequently methylated both in primary and metastatic tissues (range: 55.3% approximately 89.5%). E-cadherin was not frequently methylated in either setting (range: 18.4% approximately 23.7%). The methylation status of HIN-1, CDH13, RIL, and RARbeta2 in lymph nodes metastasis were correlated with that in primary tumors. The Pearson correlation values ranged from 0.624 to 0.472 (p values < 0.01 to 0.001). Interestingly, we observed an association between HIN-1 methylation and hormone status in metastatic lymph nodes. Hypermethylation of HIN-1 in metastasis lymph nodes was significantly associated with expression of ER (odds ratio, 1.070; P = 0.024) and with PR (odds ratio, 1.046; P = 0.026).

CONCLUSIONS

This study suggests that hypermethylation of tumor suppressor genes is extended from primary to metastatic tumors during tumor progression.

Accurate classification of sentinel lymph node metastases in patients with lobular breast carcinoma

Among pathologists there is low reproducibility in classifying small volume metastases in sentinel lymph node particularly in cases of invasive lobular carcinoma. We postulate that strict adherence to American Joint Commission on Cancer (AJCC) 2003 criteria may result in inaccurate staging of lobular carcinoma patients. We reviewed cases of metastatic lobular carcinoma in sentinel lymph node biopsies between 1998 and 2008. All sentinel lymph nodes were reassessed using strict adherence to AJCC 2003 criteria. Subsequent axillary lymph node dissection and clinical follow-up were reviewed. Fifty-one patients met our inclusion criteria and were originally classified by the primary pathologist as follows: 10 isolated tumor cells, 8 micrometastases, 27 macrometastases, and 6 'positive' cases without further classification. Cases were re-classified using strict adherence to AJCC 2003 criteria as follows: 21 isolated tumor cells, 2 micrometastases, and 28 macrometastases. Twelve isolated tumor cells cases underwent full axillary dissection, and 3 (25%) had additional macrometastases. All micrometastatic cases underwent axillary dissection; all were negative. Twenty-two macrometastatic cases underwent full axillary dissection and 16 (73%) had additional macrometastases. Diffuse single cells or small clusters should not be interpreted as isolated tumor cells in invasive lobular carcinoma sentinel lymph nodes. The criteria for assessing small volume metastases in the sentinel lymph node of patients with invasive lobular carcinoma need to be more clearly defined.

Axillary node staging by ultrasonography and fine-needle aspiration cytology in patients with breast cancer

Background

This study evaluated the role of axillary ultrasonography (AUS) and fine-needle aspiration cytology (FNAC) in preoperative staging of the axilla in patients with invasive breast cancer.

Methods

Between October 2006 and March 2009, 502 patients scheduled to undergo surgery for invasive breast cancer had preoperative AUS. All patients with suspicious nodes on ultrasonography underwent FNAC, and those with positive cytology proceeded directly to axillary node clearance. Patients with normal findings on AUS or negative cytology underwent sentinel node biopsy (SNB).

Results

A total of 137 (27·3 per cent) of 502 patients had axillary node metastases on final histology. Thirty-nine (28·5 per cent) node-positive patients were identified by AUS–FNAC and spared unnecessary SNB. AUS–FNAC had a sensitivity of 28·5 per cent and a specificity of 100 per cent for detecting axillary nodal metastases. AUS–FNAC findings were normal in all 15 patients with nodal micrometastases and in 11 patients with isolated tumour cells on histopathology. The sensitivity of AUS–FNAC had a positive correlation with invasive tumour size (odds ratio 1·03) and grade (odds ratio 2·80).

Conclusion

Preoperative AUS–FNAC avoided unnecessary SNB in 28·5 per cent of node-positive patients and in 7·8 per cent of patients overall.