EXPERIENCE OF SENTINEL NODE BIOPSY ALONE IN EARLY BREAST CANCER WITHOUT FURTHER AXILLARY DISSECTION IN PATIENTS WITH NEGATIVE SENTINEL NODE

Sentinel lymph node biopsy in breast cancer

OBJECTIVES

To report our experience in sentinel lymph node biopsy (SLNB) in early breast cancer. 

METHODS

This is a retrospective study conducted at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia between January 2005 and December 2014. There were 120 patients who underwent SLNB with frozen section examination. Data collected included the characteristics of patients, index tumor, and sentinel node (SN), SLNB results, axillary recurrence rate and SLNB morbidity.  

RESULTS

There were 120 patients who had 123 cancers. Sentinel node was identified in 117 patients having 120 tumors (97.6% success rate). No SN was found intraoperatively in 3 patients. Frozen section results showed that 95 patients were SN negative, those patients had no immediate axillary lymph node dissection (ALND), whereas 25 patients were SN positive and subsequently had immediate ALND. Upon further examination of the 95 negative SN's by hematoxylin and  eosin (H and E) and immunohistochemical staining for doubtful H and E cases, 10 turned out to have micrometastases (6 had delayed ALND and 4 had no further axillary surgery). Median follow up of patients was 35.5 months and the mean was 38.8 months. There was one axillary recurrence observed in the SN negative group. The morbidity of SLNB was minimal. 

CONCLUSION

The obtainable results from our local experience in SLNB in breast cancer, concur with that seen in published similar literature in particular the axillary failure rate. Sentinel lymph node biopsy resulted in minimal morbidity.

Accuracy of frozen section analysis of sentinel lymph nodes for the detection of Asian breast cancer micrometastasis - experience from Pakistan

BACKGROUND

Intraoperative sentinel lymph node biopsy has now become the standard of care for patients with clinically node negative breast cancer for diagnosis and also in order to determine the need for immediate axillary clearance. Several large scale studies confirmed the diagnostic reliability of this method. However, micrometastases are frequently missed on frozen sections. Recent studies showed that both disease free interval and overall survival are significantly affected by the presence of micrometastatic disease. The aim of this study was to determine the sensitivity and specificity of intraoperative frozen section analysis of sentinel lymph nodes (SLNs) for the detection of breast cancer micrometastasis and to evaluate the status of non-sentinel lymph nodes (non-SLNs) in those patients subjected to further axillary sampling.

MATERIALS AND METHODS

We performed a retrospective study on 154 patients who underwent SLN biopsy from January 2008 till October 2011. The SLNs were sectioned at 2 mm intervals and submitted entirely for frozen sections. Three levels of each section submitted are examined and the results were compared with further levels on paraffin sections.

RESULTS

Overall 40% of patients (62/154) were found to be SLN positive on final (paraffin section) histology, out of which 44 demonstrated macrometastases (>2mm) and 18 micrometastases (<2mm). The overall sensitivity and specificity of frozen section analysis of SLN for the detection of macrometastasis was found to be 100% while those for micrometastasis were 33.3% and 100%, respectively. Moreover 20% of patients who had micrometastases in SLN had positive non-SLNs on final histology.

CONCLUSIONS

Frozen section analysis of SLNs lacks sufficient accuracy to rule out micrometastasis by current protocols. Therefore these need to be revised in order to pick up micrometastasis which appears to have clinical significance. We suggest that this can be achieved by examining more step sections of blocks.

Tumor characteristics influencing non-sentinel lymph node involvement in clinically node negative patients with breast cancer

Purpose

The negative sentinel lymph node (SLN) biopsy avoids conventional axillary dissection in patients with breast cancer with clinically negative axilla. Despite negative SLN, there is a risk of leaving involved non-SLN behind in the axilla. We investigated the predictive power of tumor characteristics for non-SLN metastasis.

Methods

Lymphatic mapping with blue dye method for SLN biopsy and level 1-2 axillary dissections were performed to establish axillary status in 59 patients with T1 and T2 breast cancer and clinically negative axilla. Tumor's characteristics were histopathologically established to assess their association with non-SLN metastasis.

Results

The axilla was malignant in 23 (39%) patients. The SLN alone was metastatic in 10, both SLN and non-SLN in 9, and non-SLN alone in 4 (7%) patients. The false negative rate for SLN biopsy was 10% in our series. The rate of positive non-SLN was found as 0% in T1a-b, 19% in T1c, and 40% in T2 tumors (p=0.035). Lymphovascular invasion was positive in 14 (61%) patients with axillary metastasis (p<0.001), and in 10 (77%) patients with non-SLN involvement (p<0.001).

Conclusion

We concluded that there was a small risk of involved non-SLN despite negative SLN. Tumor size (near or greater than 2 cm) was significantly associated with non-SLN metastasis. Peritumoral lymphovascular invasion was a positive predictor of the metastatic involvement in non-SLNs.

Systematic review of the effect of external beam radiation therapy to the breast on axillary recurrence after negative sentinel lymph node biopsy

BACKGROUND

Axillary recurrence after negative sentinel lymph node biopsy (SLNB) in patients with invasive breast carcinoma remains a concern. Previous investigations to identify prognostic factors for axillary recurrence identified that a disproportionate number of patients with an axillary recurrence after negative SLNB were not treated with external beam radiation therapy (EBRT) of the breast as part of initial treatment. This finding prompted a systematic review to test the hypothesis that EBRT to the breast reduces the risk of axillary recurrence after negative SLNB.

METHODS

A literature search was performed in PubMed, the Cochrane Library and the Spanish-language database LILACS to identify articles publishing data regarding follow-up of sentinel lymph node (SLN)-negative patients. Reports and articles lacking information on the initial treatment were excluded.

RESULTS

Forty-five articles were accepted for review. A total of 23,357 SLN-negative patients were identified with median follow-up ranging from 15 to 102 months. Some 18,878 patients were treated with EBRT to the breast as part of their initial treatment. One hundred and twenty-seven patients with an axillary recurrence were identified, of whom 73 had EBRT as part of their initial treatment. Meta-analysis showed that EBRT was associated with a lower rate of axillary recurrence (P < 0·001), but this finding was subject to heterogeneity.

CONCLUSION

This review and meta-analysis showed that EBRT is associated with a significantly lower axillary recurrence rate after negative SLNB.

The Effect of Excisional Biopsy on the Accuracy of Sentinel Lymph Node Mapping in Early Stage Breast Cancer: Comparison with Core Needle Biopsy

Despite the successful application of sentinel node mapping in breast cancer patients, its use in patients with a history of previous excisional biopsy of the breast tumors is a matter of controversy. In the present study we evaluated the accuracy of sentinel node biopsy in this group of patients and compared the results with those in whom the diagnosis of breast cancer was established by core needle biopsy. Eighty patients with early stage breast carcinoma were included into our study. Forty patients had a history of previous excisional biopsy and the remainder 40 had undergone core needle biopsy. Intradermal injections of 99mTc-antimony sulfide colloid as well as patent blue were both used for sentinel node mapping. Sentinel nodes were harvested during surgery with the aid of surgical gamma probe. All patients underwent standard axillary lymph node dissection subsequently. Detection rate was 97.5 per cent for both groups of the study. Number of detected sentinel node during surgery was not significantly different between groups. False negative rate was 0 per cent for both groups of the study. In conclusion sentinel node biopsy is reliable in patients with previous history of excisional biopsy of the breast tumors and has a low false negative rate.

Breast cancer prognosis and occult lymph node metastases, isolated tumor cells, and micrometastases

BACKGROUND

The prognostic relevance of isolated tumor cells and micrometastases in lymph nodes from patients with breast cancer has become a major issue since the introduction of the sentinel lymph node procedure. We conducted a systematic review of this issue.

METHODS

Studies published from January 1, 1977, until August 11, 2008, were identified by use of MEDLINE, EMBASE, and the Cochrane Library. A total of 58 studies (total number of patients = 297,533) were included and divided into three categories according to the method for pathological assessment of the lymph nodes: cohort studies with single-section pathological examination of axillary lymph nodes (n = 285,638 patients), occult metastases studies with retrospective examination of negative lymph nodes by step sectioning and/or immunohistochemistry (n = 7740 patients), and sentinel lymph node biopsy studies with intensified work-up of the sentinel but not of the nonsentinel lymph nodes (n = 4155 patients). We used random-effects meta-analyses to calculate pooled estimates of the relative risks (RRs) of 5- and 10-year disease recurrence and death and the multivariably corrected pooled hazard ratio (HR) of overall survival of the cohort studies.

RESULTS

In the cohort studies, the presence (vs the absence) of metastases of 2 mm or less in diameter in axillary lymph nodes was associated with poorer overall survival (pooled HR of death = 1.44, 95% confidence interval [CI] = 1.29 to 1.62). In the occult metastases studies, the presence (vs the absence) of occult metastases was associated with poorer 5-year disease-free survival (pooled RR = 1.55, 95% CI = 1.32 to 1.82) and overall survival (pooled RR = 1.45, 95% CI = 1.11 to 1.88), although these endpoints were not consistently assessed in multivariable analyses. Sentinel lymph node biopsy studies were limited by small patient groups and short follow-up.

CONCLUSION

The presence (vs the absence) of metastases of 2 mm or less in diameter in axillary lymph nodes detected on single-section examination was associated with poorer disease-free and overall survival.

Axillary recurrence after a tumour-negative sentinel node biopsy in breast cancer patients: A systematic review and meta-analysis of the literature

BACKGROUND

Sentinel node biopsy became the standard of care before consensus on the technique was reached and without randomized studies having shown a similar or decreased axillary recurrence rate. The purpose of this study was to evaluate studies reporting on patients with a negative sentinel node biopsy.

METHODS

We performed a systematic review and meta-analysis of the literature for studies concerning clinically node-negative breast cancer patients with a tumour-negative sentinel node biopsy and no subsequent axillary node dissection. The axillary recurrence rate was determined, as well as the sensitivity of the sentinel node procedure and the differences in lymphatic mapping techniques.

RESULTS

Forty-eight studies concerning 14 959 sentinel node-negative breast cancer patients followed for a median of 34 months were selected. Sixty-seven patients developed an axillary recurrence, resulting in a recurrence rate of 0.3%. The sensitivity of the sentinel node biopsy was 100%. Uni- and multivariable variable analyses showed that the lowest recurrence rates were reported in studies performed in cancer centres, in studies that described the use of (99m)Tc-sulphur colloid, and also when investigators used the superficial injection technique or evaluated the harvested sentinel nodes with haematoxylin-eosin and immunohistochemistry staining (p<0.01).

CONCLUSIONS

In this systematic literature review, the axillary recurrence rate in sentinel node-negative patients is 0.3%, which is well within the desired range. The median sensitivity of the procedure appears to be as high as 100%. The recurrence rate is influenced by the differences in the lymphatic mapping technique.

Influencing factors for regional lymph node recurrence of breast cancer

INTRODUCTION

We investigated whether the risk of developing regional lymph node recurrence was dependant on the number of lymph nodes removed.

OBJECT

We followed 2,961 patients of whom 50 (1.69%) developed regional recurrent disease during a median period of 73 months (4-192 months).

RESULT

For those women who had involved lymph nodes at initial surgery we were able to establish an inverse correlation between the development of local recurrence and the number of lymph nodes removed in multivariate analysis. For women who had no affected lymph nodes, the number of lymph nodes removed did not influence the incidence of local recurrence.

CONCLUSION

We conclude from these data that women who have negative nodal status at surgical staging do not benefit from further systematic axillary resection with regard to regional lymph node recurrence. For those women, however, who have confirmed axillary metastasis, systematic axillary resection lowers the risk of regional lymph node recurrence depending on the number of lymph nodes removed.

Prediction of nonsentinel lymph node metastasis in sentinel node–positive breast carcinoma

The incidence of nonsentinel (NSN) lymph node metastases in patients with a tumor-positive sentinel (SN) lymph node varies greatly from 20% to 70% in the published literature. Current practice is that most patients with a positive SN (micro- and macrometastases) undergo a complete axillary dissection. However, it has been shown by other investigators that a large number of patients with a positive SN do not necessarily need a complete axillary dissection. In this analysis, we reviewed the pathology slides from 58 patients who had undergone SN and axillary node dissection. The tumor size, histologic parameters, receptor (estrogen and progesterone), and HER-2neu oncoprotein expression were noted. Student t test and Fisher exact test were used for statistical analysis. Of 58 patients, 19 (32.7%) had NSN metastases. Primary tumor size (P < .002), size of SN metastatic tumor (P < .03), and the presence of extracapsular tumor extension (P < .0001) were associated significantly with NSN metastases. We have shown in this study that it would be possible to predict the NSN status based on primary tumor size, size of SN metastatic tumor, and presence of SN extracapsular tumor extension.