The impact of nodal isolated tumor cells on survival of breast cancer patients

A novel nomogram and survival analysis for different lymph node status in breast cancer based on the SEER database

INTRODUCTION

The axillary lymph node status (ALNS) and internal mammary lymph nodes (IMLN) expression associated with breast cancer are closely linked to prognosis. This study aimed to establish a nomogram to predict survival at 3, 5, and 10 years in patients with various lymph node statuses.

METHODS

We obtained data from patients with breast cancer between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER database). Chi-square analysis was performed to test for differences in the pathological characteristics of the groups, and Kaplan-Meier analysis and the log-rank test were used to plot and compare the correlation between overall survival (OS) and breast cancer specific survival (BCSS). The log-rank test was used for the univariate analysis, and statistically significant characteristics were included in the multivariate and Cox regression analyses. Finally, Independent factor identification was included in constructing the nomogram using R studio 4.2.0; area under curve (AUC) values were calculated, and receiver operating characteristic (ROC) curve, calibration, and decision curve analysis (DCA) curves were plotted for evaluation.

RESULTS

A total of 279,078 patients were enrolled and analysed, demonstrating that the isolated tumour cells (ITC) group had clinicopathological characteristics similar to those of micrometastases (Mic). Multivariate analysis was performed to identify each subgroup's independent risk factors and construct a nomogram. The AUC values were 74.7 (95% CI 73.6-75.8), 72.8 (95% CI 71.9-73.8), and 71.2 (95% CI 70.2-72.2) for 3-, 5-, and 10-year OS, respectively, and 82.2 (95% CI 80.9-83.6), 80.1 (95% CI 79.0-81.2), and 75.5 (95% CI 74.3-76.8) for BCSS in overall breast cancer cases, respectively. AUC values for 3-, 5-, and 10-year OS in the ITC group were 64.8 (95% CI 56.5-73.2), 67.7 (95% CI 62.0-73.4), and 65.4 (95% CI 60.0-70.7), respectively. For those in the Mic group, AUC values for 3-, 5-, and 10-year OS were 72.9 (95% CI 70.7-75.1), 72.4 (95% CI 70.6-74.1), and 71.3 (95% CI 69.6-73.1), respectively, and AUC values for BCSS were 77.8 (95% CI 74.9-80.7), 75.7 (95% CI 73.5-77.9), and 70.3 (95% CI 68.0-72.6), respectively. In the IMLN group, AUC values for 3-, 5-, and 10-year OS were 75.2 (95% CI 71.7-78.7), 73.4 (95% CI 70.0-76.8), and 74.0 (95% CI 69.6-78.5), respectively, and AUC values for BCSS were 76.6 (95% CI 73.0-80.3), 74.1 (95% CI 70.5-77.7), and 74.7 (95% CI 69.8-79.5), respectively. The ROC, calibration, and DCA curves verified that the nomogram had better predictability and benefits.

CONCLUSION

This study is the first to investigate the predictive value of different axillary lymph node statuses and internal mammary lymph node metastases in breast cancer, providing clinicians with additional aid in treatment decisions.

Does the Presence of Cytokeratin Positive Individual Tumor Cells (N0(I+)) in Sentinel Lymph Nodes Affect Clinical Outcomes in Breast Cancer Patients Treated with Accelerated Partial Breast Irradiation

Purpose

To report a primary objective clinical outcome of ipsilateral breast cancer recurrence following accelerated partial breast irradiation (APBI) with N_0(i+) (single tumor cells or clusters <2mm) in sentinel lymph nodes. The secondary objective was to observe any incidence of ipsilateral breast failure.

Patients and Methods

Between March 2004 and April 2016, a total of 747 patients were enrolled in one of two APBI (Accelerated Partial Breast Irradiation) breast protocols (Phase II NCT01185145 and Phase III NCT01185132). Nineteen patients with N_0(i+) disease were treated between February 2005 and December 2015. Patient eligibility included a primary invasive or DCIS tumor size <3 cm, N0(i+) disease, and margin width of >2 mm. All enrolled patients presented in this report had sentinel lymph node examinations. Clinical outcomes of ipsilateral breast, axillary and combined regional (breast or axillary) recurrences were analyzed.

Results

Median follow-up for all patients was 5 years (1–8 years). No patient experienced either ipsilateral breast or axillary recurrence.

Conclusion

There has been scarce information/reporting of the treatment of patients with cytokeratin positive individual tumor cells N_0(i+) with APBI. The authors have presented data which suggest that the successful outcomes of these patients might warrant further study.

Sweeping lymph node micrometastases off their feet: an engineered model to evaluate natural killer cell mediated therapeutic intervention of circulating tumor cells that disseminate to the lymph nodes

Approximately 90% of cancer related deaths are due to metastasis. Cells from the primary tumor can metastasize through either the vascular or lymphatic circulation. Cancer cells in circulation are called circulating tumor cells (CTCs) and it has been shown that bone marrow is a niche for homing of blood borne CTCs from several epithelial tumors. Cancer cells found in bone marrow are termed disseminated tumor cells (DTCs). Likewise, CTCs in the lymphatic circulation are more often seeded in the sentinel lymph nodes (SLN) that drain the tumor. Micrometastases (<2 mm) occur after the arrest and implantation of DTCs in lymph nodes over time. This paper presents a cell culture platform termed microbubbles formed in polydimethylsiloxane (PDMS) from a microfabricated silicon wafer for mimicking lymph node micrometastases. We cultured lymph node seeking cancer cells in microbubbles to evaluate the efficacy of natural killer (NK) mediated therapy for targeting lymph node micrometastasis. The microbubble platform consists of an array of microcavities that provides a unique microenvironment for mimicking the deep cortical unit of the lymph nodes. We show that cancer cells cultured in microbubbles with therapeutic NK cells undergo apoptosis after 24 h in culture. Since lymph node metastases are prevalent across several types of cancer, this platform may be useful for developing improved cancer therapies for targeting lymph node micrometastases.

Which patients need an axillary clearance after sentinel node biopsy?

Sentinel lymph node biopsy (SLNB) is a safe and accurate minimally invasive method for detecting axillary lymph node (ALN) involvement in the clinically negative axilla thereby reducing morbidity in patients who avoid unnecessary axillary lymph node dissection (ALND). Although current guidelines recommend completion ALND when macro- and micrometastatic diseases are identified by SLNB, the benefit of this surgical intervention is under debate. Additionally, the management of the axilla in the presence of isolated tumour cells (ITCs) in SLNB is questioned. Particularly controversial is the prognostic significance of minimal SLNB metastasis in relation to local recurrence and overall survival. Preliminary results of the recently published Z0011 trial suggest similar outcomes after SNB or ALND when the SN is positive, but this finding has to be interpreted with caution.

Accuracy of sentinel node biopsy for breast cancer using blue dye alone

Blue dye alone (BDA), lymphoscintigraphy alone, or, a combination of the two techniques are used for sentinel node biopsy (SNB) in breast cancer. This study reviews the effectiveness of the SNB technique using BDA by measuring the node identification rate and comparing the cohort node positivity with expected rates from established nomograms. A consecutive case series was examined from the database. This included the learning experience of six surgeons. Patients with unifocal tumors estimated at less than 31 mm were eligible. The tumor and axillary nodal histology was recorded. Published data were then used to calculate and predict node positivity rates in the study according to the size and grade of the tumors. There were 332 SNB procedures from 2001 to 2008. BDA successfully identified nodes in 94.6% (314/332) of the cases. The identification rate improved with experience. In patients with invasive cancer, 28.4% (85/299) of SNB were found to be positive for metastases or micrometastases. The node identification rate and the node positivity rate were found to be within published predicted ranges for the size and grade of the study tumors. The SNB with BDA was found to be effective in identifying sentinel nodes (SLN) in breast cancer. Surgeon experience was a factor in the success of the technique. Rates of detecting metastases were consistent with internationally published data, suggesting that BDA may perform as well as other techniques in experienced hands.

Breast cancer survival in relation to the metastatic tumor burden in axillary lymph nodes

PURPOSE

The aim of this study was to determine the prognostic significance of lymph node micrometastases in patients with breast cancer.

PATIENTS AND METHODS

Between September 2000 and January 2004, 3,369 patients with breast cancer were included in a prospective cohort. According to their lymph node status, they were classified in the following four groups: 2,383 were node negative, 107 had isolated tumor cells, 123 had micrometastases, and 756 had macrometastases. Median follow-up time was 52 months. Kaplan-Meier estimates and the multivariate Cox proportional hazard regression model were used to analyze survival.

RESULTS

Five-year cause-specific and event-free survival rates were lower for patients with micrometastases (pN1mi) than for node-negative (pN0) patients (94.1% v 96.9% and 79.6% v 87.1%, respectively; P = .020 and P = .032, respectively). There was no significant survival difference between node-negative patients and those with isolated tumor cells. The overall survival of pN1mi and pN0 patients did not differ.

CONCLUSION

This study demonstrates a worse prognosis for patients with micrometastases than for node-negative patients.

Cytokeratin 19-positive circulating tumor cells in early breast cancer prognosis

In spite of the heterogeneity of breast cancer at the molecular level, circulating tumor cells (CTCs) may provide a novel prognostic marker. Approximately 20–40% of early breast cancer patients have detectable CTCs using reverse transcription PCR for CK19. The detection of CTCs before adjuvant chemotherapy or during tamoxifen administration has been demonstrated to be an independent adverse prognostic factor in women with early-stage breast cancer. The prognostic value of CTC detection is of great significance in subgroups of patients with estrogen receptor-negative and human EGF receptor 2-positive tumors. Prospective clinical trials are warranted in order to validate the use of CTCs as predictive and/or prognostic markers and assess their utility in individualizing therapy of patients with early breast cancer.

Sentinel node biopsy in breast cancer: five years experience from Denmark

INTRODUCTION

Danish experience from the first five years with sentinel lymph node biopsy (SLNB) as a routine staging procedure in early breast cancer is reported.

METHODS

During the period January 1, 2002 to December 31, 2006, 14 923 patients were diagnosed at Danish breast surgical centers certified for the sentinel node method. SLNB was performed in 8 338 patients (55.9%). The fraction increased steadily from 43% in 2002 to 67% in 2006. The median follow-up was 1.7 year (range 0-5.2 years).

RESULTS

Patients staged with SLNB were younger, had more often BCS, had smaller tumor size, were more often hormone receptor positive, and had lower grade, than patients staged with lymph node dissection (ALND). Blue dye and radio colloid were used in combination in 82%. Lymphoscintigraphy was performed in 61%, and frozen section was performed in 87%. Originally, peritumoral injection of tracer was most often used, but the recommendations have changed, and in 2006 90% of cases had sub-or periareolar injection of radioactive tracer. In the sentinel nodes 25% had macrometastases, 17% micrometastases only, and 3.2% isolated tumor cells only (ITC). ALND was performed in 2 714 patients, whose lymph node classification by SN was known. In the group of 1 563 patients with macrometastases in SN, 45% had non-sentinel node metastases, and in the group of 942 patients with micrometastases only, 23% had more positive nodes. Regional lymph node metastases were found in 15% with ITC in sentinel nodes. Lymph node recurrence among node negative patients was observed more often after staging by SLNB (0.5%) than after ALND (0.2%, p =0.04).

CONCLUSION

Two thirds of breast cancer patients can be safely staged with the sentinel node technique, half of these will need no further axillary surgery. The loco-regional control in node negative patients classified by SLNB is high, but seems not quite comparable to what is seen after ALND.

Estrogen receptor immunohistochemistry for confirmation of sentinel lymph node metastasis in cases with equivocal cytokeratin positivity

Differentiation of true metastases from cytokeratin (CK)-positive nonepithelial cells by immunohistochemistry occasionally may be difficult in the evaluation of sentinel lymph nodes (SLNs) for occult breast carcinoma metastases. In this study, we evaluated estrogen receptor (ER) immunostaining superimposed on CK as a method for the confirmation of metastasis when CK immunostaining alone was equivocal. We performed sequential ER staining on previously CK-stained slides on 15 axillary SLNs from breast cancer patients: 5 SLNs with known metastatic carcinoma (positive controls), 6 known negative SLNs (negative controls), and 4 test cases (3 SLNs in which CK-positive cells were equivocal for malignancy and 1 SLN in which metastasis was obvious, but contained focal weakly CK-positive signet ring cells). The primary tumor in all cases expressed ER in >50% of cells. Only 3 of 5 positive controls showed metastatic cells with dual CK/ER staining. CK-positive reticulum cells in all negative controls were ER negative. Three test cases showed dual CK/ER staining in the equivocal cells. The case with signet ring cells showed strong ER staining in the nonsignet ring cells and weaker staining in the signet ring cells. We conclude that dual CK/ER staining can be useful in SLNs when CK staining alone is equivocal, particularly when the primary tumor is known to have high expression of ER. Although dual ER/CK positivity helps to confirm metastasis, negative ER staining does not exclude metastatic disease.

Predicting the Likelihood of Additional Nodal Metastases in Breast Carcinoma Patients With Positive Sentinel Node Biopsy

Axillary lymph node dissection (ALND) is an important procedure in the staging of breast cancer patients. However, it is associated with a significant morbidity rate. In addition, using early diagnosis a high number of cases with negative lymph nodes can be identified. A lymph node defined as sentinel lymph node (SLN) would be the first to receive tumoral drainage. A less morbid but accurate staining procedure using mapping and SLN biopsy has been introduced. The aim of this study was to estimate the likelihood of additional disease in the axilla after SLN analysis. A total of 259 breast carcinomas and SLN biopsies followed by ALND were examined. The patient median age was 59 years, approximately 75% of them postmenopausal. Tumor size was 1.4 ± 0.8 cm (almost 80% in pT1). SLNs were positive in 59 of 259 (22.8%) carcinomas, 30 (11.6%) with micrometastases (<2.0 mm) and 29 (11.2%) with metastases. Tumor size ( P = .004) and presence of lymphovascular invasion (LVI; P = .034) were found to be significant predictors of pathologically positive SLN. Following ALND, positive non-SLNs were present mostly in patients with metastasis >2 mm in SLN ( P = .003), in carcinoma with higher nuclear grade ( P = .044), decreased estrogen receptor (ER; P = .042), and progesterone receptor (PR; P = .042). Finally, lymph node status (pN) following SLN and ALND was found to be significantly associated with tumor size ( P = .006), LVI ( P = .037), PR ( P = .023), and Her-2 status ( P < .001). These results point to detailed analysis of primary tumor and SLN that may increase the precision of patient selection for further axillary surgery or radiotherapy.

Lobular phenotype related to occult-metastatic spread in axillary sentinel node and/or bone marrow in breast carcinoma

To determine whether any histological trait was associated with regional and/or systemic spread of occult tumour cells (OTCs) in small size invasive breast cancer, we compared tumour characteristics, axillary sentinel lymph node (SN) and bone marrow (BM) status in a series of 287 pT1T2 cases. Surgery was the first step of treatment, associated with SN procedure and with BM aspiration for the detection of OTC. SN was histologically classified as negative, metastatic (>2mm), micro-metastatic (>0.2mm and 2mm) or involved by OTC detected by immunohistochemistry (Ni+, 0.2mm). BM specimens were analysed after immunocytochemistry and classified as negative or positive with atypical cytokeratin-positive OTC. Metastasis and micro-metastasis in the SN were correlated with size, grade and vascular invasion. In contrast, presence of OTC in both SN and BM was independent of these parameters but positively associated with lobular type. This correlation was also observed for BM status, which was similarly independent of the tumour characteristics. No association was found between SN status and BM status. Our data indicate that, in the course of breast cancer, OTC spreading is frequent and could be an early event, related to lobular histological type but independent of classical histoprognostic parameters, and that the loco-regional metastatic spread of OTC is not a prerequisite for systemic involvement.

Non-sentinel lymph node metastases associated with isolated breast cancer cells in the sentinel node

There are many reports on the frequency of non-sentinel lymph node involvement when isolated tumor cells are found in the sentinel node, but results and recommendations for the use of an axillary lymph node dissection differ among studies. This systematic review was conducted to give an overview of this issue and to provide recommendations for the use of an axillary lymph node dissection in these patients. We searched Medline, Embase, and Cochrane databases from January 1, 2002, through November 27, 2007, for articles on patients with invasive breast cancer who had isolated tumor cells in the sentinel lymph node (according to the sixth edition of the Cancer Staging Manual of the American Joint Committee on Cancer) and who also underwent axillary lymph node dissection. Of 411 selected articles, 29 (including 836 patients) were included in this review. These 29 studies were heterogeneous, reporting a wide range of non-sentinel lymph node involvement (defined as the presence of isolated tumor cells or micro- or macrometastases) associated with isolated tumor cells in the sentinel lymph node, with an overall pooled risk for such involvement of 12.3% (95% confidence interval = 9.5% to 15.7%). This pooled risk estimate was marginally higher than the risk of a false-negative sentinel lymph node biopsy examination (ie, 7%-8%) but marginally lower than the risk of non-sentinel lymph node metastases in patients with micrometastases (ie, approximately 20%) who are currently eligible for an axillary lymph node dissection. Because 36 (64%) of the 56 patients with isolated tumor cells in their sentinel lymph node also had non-sentinel lymph node macrometastases, those patients with isolated tumor cells in the sentinel lymph node without other indications for adjuvant systemic therapy might be candidates for axillary lymph node dissection.

Promoter hypermethylation in sentinel lymph nodes as a marker for breast cancer recurrence

PURPOSE

Promoter methylation of tumor suppressor genes in histologically negative sentinel lymph nodes (HNSN) of early stage breast cancer patients has not been extensively studied. This study evaluates the methylation frequency and pattern in HNSN to determine if detection of hypermethylation of one or more genes is associated with an increased recurrence risk in node negative breast cancer.

EXPERIMENTAL DESIGN

In 1998, a prospective study of patients with early stage breast cancer and HNSN was initiated in order to correlate sentinel node analysis with clinical outcome. Nodal tissue was selected from 120 HNSN patients for methylation analysis in at least one and up to six sentinel nodes using a panel of nine genes. Corresponding primary breast tumors from 79 patients were also evaluated for hypermethylation. Methylation analysis was performed using nested Methylation Sensitive PCR (n-MSP). Logistical regression was used to evaluate the relationship between clinical recurrence and methylation status.

RESULTS

Over a median follow-up of 79 months, 13 of the 120 patients had clinical recurrence. Hypermethylation of genes was frequently observed in HNSN, but there was no correlation of methylation pattern and clinical recurrence. However, increased frequency of gene methylation of the primary tumor correlated with clinical recurrence.

CONCLUSIONS

Although hypermethylation of multiple genes occurs frequently in HNSN of breast cancer patients, it is not associated with breast cancer recurrence in the first 7 years of clinical follow-up.

Micrometastatic spread in breast cancer: detection, molecular characterization and clinical relevance

Immunocytochemical or molecular assays allow the detection of single disseminated tumor cells (DTCs) in the bone marrow (BM) or the peripheral blood in 10% to 60% of breast cancer patients without signs of metastasis. Results from recently reported studies suggest that circulating tumor cell (CTC) levels may serve as a prognostic marker and be used for early assessment of therapeutic response in patients with metastatic breast cancer. In early stage breast cancer, however, the impact of CTCs is less well established than that of DTCs in BM, where several clinical studies demonstrated that such cells are an independent prognostic factor at primary diagnosis. The characterization of DTCs/CTCs has already shed new light on the complex process underlying early tumor cell dissemination and metastatic progression in cancer patients. Characterization of DTCs should help to identify novel targets for biological therapies aimed to prevent metastatic relapse. In addition, understanding tumor 'dormancy' and identifying metastatic stem cells might result in the development of new therapeutic concepts.

Sentinel node biopsy: interpretation and management of patients with immunohistochemistry-positive sentinel nodes and those with micrometastases

The sentinel node procedure is an adequate tool to identify lymph node metastasis in breast cancer. Sentinel nodes are generally examined with greater attention mainly to exclude, as reliably as possible, lymph node metastasis. To achieve this, many protocols are used, resulting in different rates of micrometastasis or isolated tumor cells encountered. Since the prognostic significance of isolated tumor cells or micrometastasis in the sentinel nodes, and the risk of further axillary lymph node involvement in patients with isolated tumor cells, is uncertain and at most limited, these findings may pose difficulties for clinicians in clinical decision making. Protocols that identify lymph node metastasis, from which the clinical relevance is known, are warranted. Unnecessary lymph node dissections should be avoided.

Adjuvant chemotherapy for early-stage breast cancer

Systemic chemotherapy is an integral component of the adjuvant treatment strategy for women who have early-stage breast cancer and accounts for significant improvements in breast cancer-specific mortality. Decisions regarding adjuvant therapy are increasingly complex with the advent of new therapeutic strategies, a growing body of literature on the molecular biology and natural history of breast cancer, and advances in therapeutic techniques and early detection. Ultimately, the risk-benefit calculus will continue to evolve in response to these advances and one hopes that clinicians will soon be able to tailor treatment recommendations to the biology of an individual cancer and the needs of the affected individual.