Second thoughts on sentinel lymph node biopsy in node-negative breast cancer

Axillary recurrence rate 5 years after negative sentinel node biopsy for breast cancer

BACKGROUND

Sentinel lymph node (SLN) biopsy has replaced axillary lymph node dissection (ALND) as the standard axillary staging procedure in breast cancer. Follow-up studies in SLN-negative women treated without ALND report low rates of axillary recurrence, but most studies have short follow-up, and few are multicentre studies.

METHODS

Between September 2000 and January 2004, patients who were SLN-negative and did not have ALND were included in a prospective cohort. Kaplan-Meier estimates were used to analyse the rates of axillary recurrence and survival. The risk of axillary recurrence was also compared in centres with high and low experience with the SLN biopsy (SLNB) technique.

RESULTS

A total of 2195 patients with 2216 breast tumours were followed for a median of 65 months. Isolated axillary recurrence was diagnosed in 1·0 per cent of patients. The event-free 5-year survival rate was 88·8 per cent and the overall 5-year survival rate 93·1 per cent. There was no difference in recurrence rates between centres contributing fewer than 150 SLNB procedures to the cohort and centres contributing 150 or more procedures.

CONCLUSION

This study confirmed the low risk of axillary recurrence 5 years after SLNB for breast cancer without ALND.

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.

Early breast cancer

Adoption of urbanised lifestyles together with changes in reproductive behaviour might partly underlie the continued rise in worldwide incidence of breast cancer. Widespread mammographic screening and effective systemic therapies have led to a stage shift at presentation and mortality reductions in the past two decades. Loco-regional control of the disease seems to affect long-term survival, and attention to surgical margins together with improved radiotherapy techniques could further contribute to mortality gains. Developments in oncoplastic surgery and partial-breast reconstruction have improved cosmetic outcomes after breast-conservation surgery. Optimum approaches for delivering chest-wall radiotherapy in the context of immediate breast reconstruction present special challenges. Accurate methods for intraoperative assessment of sentinel lymph nodes remain a clinical priority. Clinical trials are investigating combinatorial therapies that use novel agents targeting growth factor receptors, signal transduction pathways, and tumour angiogenesis. Gene-expression profiling offers the potential to provide accurate prognostic and predictive information, with selection of best possible therapy for individuals and avoidance of overtreatment and undertreatment of patients with conventional chemotherapy. Short-term presurgical studies in the neoadjuvant setting allow monitoring of proliferative indices, and changes in gene-expression patterns can be predictive of response to therapies and long-term outcome.

Resolving the controversies surrounding lymphatic mapping in breast cancer

Sentinel lymph node biopsy has rapidly become the standard of care in the primary treatment of breast cancer. Most of the initially identified potential contraindications towards the procedure, such as nonpalpability, large tumor size, pregnancy and being previously operated in the breast or axilla, have been ruled out, whereas multifocality represents an unsolved problem. There is no consensus about the best use of the technique in patients receiving neoadjuvant treatment. There is no place for sentinel lymph node biopsy in pure ductal carcinoma in situ, but it can be used for large high-grade in situ cancer diagnosed through core biopsy, especially if a mastectomy is planned. Morbidity is low, and the recurrence rates reported so far are reassuring. However, long-term results are lacking, and results from ongoing randomized trials are awaited.