Moving a neodymium magnet promotes the migration of a magnetic tracer and increases the monitoring counts on the skin surface of sentinel lymph nodes in breast cancer.

BACKGROUND: We suspected that moving a small neodymium magnet would promote migration of the magnetic tracer to the sentinel lymph node (SLN). Higher monitoring counts on the skin surface before making an incision help us detect SLNs easily and successfully. The present study evaluated the enhancement of the monitoring count on the skin surface in SLN detection based on the magnet movement in a sentinel lymph node biopsy (SNB) using superparamagnetic iron oxide (SPIO) nanoparticles. METHODS: After induction of general anesthesia, superparamagnetic iron oxide nanoparticles were injected sub-dermally into the subareolar area or peritumorally. The neodymium magnet was moved over the skin from the injection site to the axilla to promote migration of the magnetic tracer without massage. A total of 62 patients were enrolled from February 2018 to November 2018: 13 cases were subjected to magnet movement 20 times (Group A), 8 were subjected to 1-min magnet movement (Group B), 26 were given a short (about 5 min) interval from injection to 1-min magnet movement (Group C), and 15 were given a long (about 25 min) interval before 1-min magnet movement using the magnetometer's head (Group D). In all cases, an SNB was conducted using both the radioisotope (RI) and SPIO methods. The monitoring counts on the skin surface were measured by a handheld magnetometer and compared among the four groups. Changes in the monitoring count by the interval and magnet movement were evaluated. RESULTS: The identification rates of the SPIO and RI methods were 100 and 95.2%, respectively. The mean monitoring counts of Group A, B, C, and D were 2.39 µT, 2.73 µT, 3.15 µT, and 3.92 µT, respectively (p < 0.0001; Kruskal-Wallis test). The monitoring counts were higher with longer magnet movement and with the insertion of an interval. Although there were no relationships between the monitoring count on the skin surface and clinicopathologic factors, magnet movement strongly influenced the monitoring count on the skin surface. CONCLUSION: Moving a small neodymium magnet is effective for promoting migration of a magnetic tracer and increasing monitoring counts on the skin surface. TRIAL REGISTRATION: UMIN, UMIN000029475. Registered 9 October 2017.

RNA recovery from specimens of duct-washing cytology performed contemporaneously with mammary ductoscopy.

OBJECTIVE: Conventional cytological diagnosis including duct-washing cytology (DWC) is sometimes performed using ductal epithelial cells collected during mammary ductoscopy; it is useful for detection of early-stage breast cancer such as ductal carcinoma in situ (DCIS). However, conventional cytological diagnosis focuses exclusively on cellular morphology; false negatives and false positives may be caused by inadequate specimen preparation (triggering cell degeneration) or poor examiner diagnostic skills. Molecular diagnosis using RNA biomarkers is expected to compensate for the weaknesses of cytological diagnosis. We previously employed microarray analysis to identify highly expressed genes in DCIS, suggesting that they may be useful for DCIS diagnosis. Here, we explored whether DWC samples yielded RNA of sufficient quantity and quality for RNA biomarker-based diagnosis. RESULTS: We extracted RNAs from 37 DWC samples. RNA from 12 samples exhibited RNA integrities of ≥ 6, indicative of moderate-to-high quality. We then showed that cocaine and amphetamine regulated transcript prepropeptide (CARTPT) and breast cancer-associated transcript 54 (BRCAT54) mRNA-previously shown by microarray analysis to be highly expressed in DCIS-were detectable in these samples. Therefore, DWC samples may be useful for molecular diagnosis involving RNA biomarkers.

Microarray analysis of ductal carcinoma in situ samples obtained by puncture from surgical resection specimens.

OBJECTIVE: The incidence of ductal carcinoma in situ (DCIS) is increasing due to more widespread mammographic screening. DCIS, the earliest form of breast cancer, is non-invasive at the time of detection. If DCIS tissues are left undetected or untreated, it can spread to the surrounding breast tissue. Thus, surgical resection is the standard treatment. Understanding the mechanism underlying the non-invasive property of DCIS could lead to more appropriate medical treatments, including nonsurgical options. DATA DESCRIPTION: We conducted a microarray-based genome-wide transcriptome analysis using DCIS specimens obtained by puncture from surgical specimens immediately after surgery.

Utility of duct-washing cytology for detection of early breast cancer in patients with pathological nipple discharge: A comparative study with fine-needle aspiration cytology.

BACKGROUND: Pathological nipple discharge (PND) is a relatively common symptom of breast cancer affecting the nipple. Mammary ductscopy (MD) allows direct visualization of the ductal lumen and collection of a cytological specimen using duct-washing cytology (DWC). Herein, we clarified the diagnostic efficacy of DWC for the detection of breast cancers with PND, compared with fine-needle aspiration cytology (FNAC). METHODS: We retrospectively examined 48 patients with PND who underwent DWC by MD (ductosccopy group; histologically determined by intraductal biopsy [IDB] or surgical specimen). The results of sensitivity and specificity of DWC were compared with that of FNAC (conventional group; histologically determined by core needle biopsy). Clinicopathological factors were compared between the ductoscopy and the conventional groups. RESULTS: Of eight histologically malignant cases in the ductoscopy group, one case was cytologically judged as malignant and three as indeterminate. Sensitivity and specificity of DWC were 50.0% and 82.5%, respectively. Malignant cases were mostly solid papillary carcinomas (SPCs), and benign cases were intraductal papillomas (IDPs). In the conventional group, sensitivity and specificity of FNAC were 88.0% and 38.2%, respectively, and malignant cases were mainly invasive carcinomas of no special type. Tumors in the ductocsopy group had more favorable prognostic features than those in the conventional group. CONCLUSION: DWC has limited diagnostic value due to the high incidence of SPC, whose cytological features are indistinguishable from IDP. As DWC alone may be unreliable, comprehensive examination with IDB and MD findings is recommended.