Sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with node-positive breast cancer: guiding a more selective axillary approach.

PURPOSE: The role of sentinel lymph node biopsy (SLNB) in breast cancer patients who undergo neoadjuvant chemotherapy (NAC) remains controversial. This study aims to investigate if axillary lymph node dissection (ALND) could be safely omitted after a negative SLNB in cN1/2 patients who become cN0 after NAC. METHODS: We retrospectively assessed T1-4, cN1/2 patients who were submitted to NAC between 2010 and 2016. T1-T3 patients who achieved complete axillary clinical response underwent SLNB. Those whose SLNs were negative were not subjected to additional ALND. The oncological outcomes of the patients were analyzed. RESULTS: Fifty-nine T1-T3 patients (45.0%) achieved a complete axillary response (cN0), and were selected to undergo SLNB. SLNs were detected in 55 of them (93.2%). Seventeen of those patients (30.9%) had SLN metastases detected and subsequently underwent ALND. In contrast, 38 patients (69.1%) had no nodal metastases detected and were managed without complementary ALND. After a mean follow-up of 55.8 months, only one patient (2.6%) submitted to SLNB without a complementary ALND had axillary recurrence as compared with three patients (3.2%) in the ALND group (p = 0.71). Distant recurrence occurred more frequently among patients submitted to ALND (92.1%) than among those only submitted to SLNB (7.9%) (p < 0.0006). Overall survival and disease-free survival were significantly better in patients who were not submitted to ALND. CONCLUSION: SLNB could be successfully used in guiding a more selective axillary approach in cN+ patients that became cN0 after NAC. Omitting ALND in CN0 patients with negative SLNs did not seem to compromise disease control and oncological outcomes.

Influence of CYP2D6 and CYP3A4 Phenotypes, Drug Interactions, and Vitamin D Status on Tamoxifen Biotransformation.

OBJECTIVE: In view of the large variability on therapeutic response and the multiple factors associated to tamoxifen (TAM) metabolic activation, this study aimed to evaluate the effect of CYP2D6 and CYP3A4 phenotypes, drug interactions, and vitamin D exposure on TAM metabolism in a group of breast cancer patients. METHODS: Trough blood samples were collected from 116 patients. TAM and metabolites endoxifen (EDF), N-desmethyltamoxifen, and 4-hydroxytamoxifen (HTF) were measured in plasma by liquid chromatography-tandem mass spectrometry. CYP2D6 and CYP3A4 phenotyping were obtained according to [dextromethorphan]/[dextrorphan] and [omeprazole]/[omeprazole sulfone] metabolic ratios, measured by high-performance liquid chromatography in plasma collected 3 hours after oral administration of 33 mg of dextromethorphan and 20 mg of omeprazole. Vitamin D3 was measured in plasma by high-performance liquid chromatography-ultraviolet. Data on concomitant use of drug considered as CYP2D6 and CYP3A4 inhibitor or inducer and vitamin D supplementation were recorded. RESULTS: About 20% of patients had reduced CYP2D6 metabolic activity and 7% CYP3A4 impaired metabolism. EDF levels diminished proportionally to the reduction of CYP2D6 metabolic activity (poor metabolizer 2.79 ng·mL, intermediate metabolizer (IM) 5.36 ng·mL, and extensive metabolizer 10.65 ng·mL, P < 0.01). Median plasma levels of TAM (161.50 ng·mL) and HTF (1.32 ng·mL) in CYP2D6 IM/CYP3A4 poor metabolizer patients were higher (P < 0.05) than those from CYP2D6 IM/CYP3A4 extensive metabolizer patients (122.07 ng·mL and 0.61 ng·mL, respectively). Seasons contributed to the interpatient variability of EDF and HTF levels; summer concentrations were 24% and 42% higher compared with winter. Vitamin D3 was not associated to CYP3A4 metabolic activity, indicating that other mechanisms might be involved in the relation between TAM metabolism and vitamin D exposure. CONCLUSIONS: CYP3A4 contributes to the bioactivation of TAM through formation of HTF and becomes increasingly important in case of reduced or absent CYP2D6 activity. EDF and HTF exposure were associated to seasonal variations, with considerable higher plasma concentrations during summer.

Comparison between preoperative and intraoperative injection of (99m)Tc Dextran-500 for sentinel lymph node localization in breast cancer.

A retrospective study was conducted from a review of the medical records of patients with early-stage, invasive breast cancer who underwent surgical treatment and sentinel node biopsy with a radiotracer from January 2008 to August 2012 at a single institution (221 patients included). The patients were grouped according to the time of (99m)Tc Dextran-500 injection, which was preoperatively (with lymphoscintigraphy) (81 patients) or intraoperatively (140 patients). The purpose of the report is to compare the results of sentinel node biopsy of early-stage breast cancer patients who were subjected to intraoperative (99m)Tc Dextran-500 injections with the patients who received preoperative injections. The following parameters were analyzed: clinical tumor staging, histological and pathological results, size and number of tumor foci, peritumoral vascular invasion, number of lymph nodes removed, size of lymph node metastasis and hormone receptor expression.There were no differences in sentinel lymph node localization whether (99m)Tc Dextran-500 was injected preoperatively or intraoperatively.

Gigantomastia / Gigantomastia

A gigantomastia é um desenvolvimento anormal e rápido da glândula mamária, de grandes proporçöes e de etiologia desconhecida, mais observada na mulher jovem, que pode ocorrer durante a gravidez ou adolescência. Säo relatados quatro casos diagnosticados no Serviço de Mastologia do Hospital de Clínicas de Porto Alegre, no período de 1985 a 1995. Além de caracterizar melhor esta patologia, que causa grandes transtornos de ordem física e psicológica, os autores destacam os aspectos do diagnóstico, complicaçöes, tratamento e associaçäo com outras enfermidades.