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Estudiar la viabilidad y utilidad de la técnica combinada biopsia selectiva de ganglio centinela (BSGC)-biopsia radioguiada del ganglio patológico en pacientes con cáncer de mama y afectación axilar sometidas a quimioterapia neoadyuvante (QTNA). Estudio prospectivo en el que se incluyeron 30 pacientes con cáncer de mama y estadificación axilar cN1, con indicación de QTNA. El ganglio biopsiado se marcó (GBM) mediante un clip, antes del tratamiento QTNA. Tras completar este se valoró la respuesta axilar con ecografía. En caso de buena respuesta ecográfica se procedió a realizar BSGC (99mTc-nanocoloides) y disección axilar dirigida mediante biopsia radioguiada del GBM (99mTc-macroagregados albúmina). Se procedía a realizar una linfadenectomía axilar si el ganglio centinela (GC) y/o el GBM contenían células tumorales. Se evaluaron las tasas de localización-exéresis del GC y del GBM. También se evaluaron la tasa de falsos negativos y el valor predictivo positivo de la BSGC sola. Se extirpó el GC en todas las pacientes, mientras que el GBM se extirpó exitosamente en 27 (90%). El GC coincidió con el GBM en 15 pacientes (50%). En 12 pacientes el GC fue negativo pero el GBM fue positivo para metástasis, lo que comportó una tasa de falsos negativos del 44,4% y un valor predictivo positivo del 37% para la BSGC sola. Tanto el GC como el GBM resultaron negativos en 5 pacientes (18,5%), lo que permitió evitar realizarles la linfadenectomía axilar. La técnica combinada descrita BSGC-biopsia radioguiada del ganglio patológico es un procedimiento útil y accesible para la reestadificación precisa de la axila tras QTNA, evitando la alta tasa de falsos negativos de la BSGC sola en este grupo de pacientes y evitando un número mayor de linfadenectomías axilares. To study the feasibility and usefulness of the combined technique selective sentinel lymph node biopsy (SLNB)-radioguided biopsy of the pathological lymph node in patients with breast cancer and axillary involvement undergoing neoadjuvant chemotherapy (NAC). Prospective diagnostic study of 30 patients with breast cancer and cN1 axillary staging with NACT indication. Before NACT, the biopsied node was marked with a clip (MBN). After NACT an ultrasound was performed and in case of good response a SLNB (99mTc-nanocolloids) plus targeted axillary dissection MBN pathologic node radioguided biopsy (99mTc-albumin macroaggregates) was performed. Axillary lymph node dissection was performed if SLNB and/or MBN were positive for tumor cells. The localization-removal rate of the sentinel lymph node (SLN) and MBN were evaluated. False-negative rate and positive predictive value of SLNB alone were also evaluated. Thirty patients were included in the study. SLN could be detected in all patients while MBN was successfully removed in 27 (90%). The SLN coincided with MBN in 15 patients (50%). In 12 patients SLNB was negative while MBN positive, leading to a FNR of 44,4% for SLNB alone. We found a positive predictive value of 37% for the SLNB. In 5 patients (18,5%) both SLNB and MBN were negative, avoiding axillary lymph node dissection. SLNB-MBN radioguided biopsy combined technique is a useful and accessible procedure for accurate axillary restaging after NACT, avoiding the high rate of false-negative rate of SLNB alone in this group of patients and avoiding a great number of axillary lymph node dissection. [ABSTRACT FROM AUTHOR]

This article presents two prototypes of laboratory magnetic separators that generate high gradient magnetic fields. Such a field is created in a separation cell via steel wool. The efficiency of separators was tested on a water suspension containing weakly magnetic Fe2O3nano/micro-particles, prepared in three size fractions in a size range of 60 nm – 10 μm. The separation process was evaluated via optical transmittance of the suspension before and after sequential separation processes. Repeated separations on the same sample exhibit an asymptotic trend that results in the conclusion that it is not possible to trap all solid content. According to the decrease of solid particles concentrations during cyclic separation we set the efficiency of the process. It is maximally 46% for fine fraction, 65% for medium fraction, and 40% for coarse fraction after infinity separation cycles. [ABSTRACT FROM AUTHOR]