Sentinel lymph node biopsy using single-agent mapping tracer (blue dye) after neoadjuvant chemotherapy in a Brazilian cohort of breast cancer patients. Real world evidence

ABSTRACT Purpose To reduce false-negative rates (FNR) in sentinel lymph node biopsy (SLNB) of clinically positive (cN+) axilla in patients undergoing neoadjuvant chemotherapy (NAC). The removal of three or more lymph nodes with dual-tracer mapping including a radioisotope was used. However, in the Brazilian Unified Health System, the radioisotope tracer is not feasible in some hospitals. We conducted a cross-sectional study to evaluate the detection rate of sentinel lymph node (SLN) in patients who converted from cN+ to ycN0 after NAC using blue dye as a single-agent mapping tracer. Methods During the period of March 2018 to September 2019, 34 patients who underwent NAC with cN+ who converted to ycN0 were enrolled in the study. The SLNB was performed using blue dye as a single-agent mapping followed by axillary lymph node dissection (ALND). Results The detection rate of sentinel lymph node was of 85.3%, being SLNB not possible for five patients (14.7%), due to fibrosis. The mean number of removed SLN was 2.5. Conclusions The use of blue dye as a single-agent mapping tracer demonstrated an acceptable detection rate of 85.3%. Although the FNR was possible to be determined, the small sample size might overestimate this rate. The removal of three or more lymph nodes with single-agent mapping tracer might be indicated for breast cancer patients who converted to ycN0 after NAC in the Brazilian health public services, in which radioisotope tracer is not suitable.

Transanal endoscopic operation for rectal cancer after neoadjuvant therapy

PURPOSE: In this paper we report the oncological outcomes from clinical series of patients with rectal cancer submitted to local excision after neoadjuvant therapy and discuss the indications for local excision in partial clinical responders. METHODS: We analysed a prospective database of 39 patients submitted to a transanal endoscopic operation for rectal cancer after neoadjuvant chemoradiation between 2006 and 2015, comparing clinical and pathological variables, perioperative complications, recurrence rate and overall survival. RESULTS: We obtained 15.4% ypT0, 17.9% ypT1, 35.9% ypT2 and 28.2% ypT3. After a median follow-up of 24 months, tumoral recurrence was observed in 4 patients, one of them with isolated pulmonary metastasis. R0 resection was achieved in 79.5%, and postoperative complications were observed in 30.2% patients and no perioperative mortality occur. Compromise surgical margins do not affect recurrence rate, and 94.9% of patients are alive nowadays. CONCLUSION: Local excision could be associated with low recurrence rate and good overall survival. Short hospitalization time and low level of serious complications observed could be an interesting option for patients who would not tolerate a radical procedure or for those who declined a total mesorectal excision. A strict long-term follow-up must be warranted to detect early tumoral recurrence.(AU)