Factors associated with upstaging in patients preoperatively diagnosed with ductal carcinoma in situ by core needle biopsy

Objective: Patients preoperatively diagnosed with ductal carcinoma in situ(DCIS) by core needle biopsy(CNB) exhibit a significant risk for upstaging on final pathology, which leads to major concerns of whether axillary staging is required at the primary operation. The present study aimed to identify clinicopathological factors associated with upstaging in patients preoperatively diagnosed with DCIS by CNB.Methods: The present study enrolled 604 patients(cN0 M0) with a preoperative diagnosis of pure DCIS by CNB, who underwent axillary staging between August 2006 and December 2015, at Fudan University Shanghai Cancer Center(Shanghai, China).Predictive factors of upstaging were analyzed retrospectively.Results: Of the 604 patients, 20.03%(n = 121) and 31.95%(n = 193) were upstaged to DCIS with microinvasion(DCISM) and invasive breast cancer(IBC) on final pathology, respectively. Larger tumor size on ultrasonography(> 2 cm) was independently associated with upstaging [odds ratio(OR) 1.558, P = 0.014]. Additionally, patients in lower breast imaging reporting and data system(BI-RADS) categories were less likely to be upstaged(4 B vs. 5: OR 0.435, P = 0.002;4 C vs. 5: OR 0.502, P = 0.001). Overall,axillary metastasis occurred in 6.79%(n = 41) of patients. Among patients with axillary metastasis, 1.38%(4/290), 3.31%(4/121)and 17.10%(33/193) were in the DCIS, DCISM, and IBC groups, respectively.Conclusions: For patients initially diagnosed with DCIS by CNB, larger tumor size on ultrasonography(> 2 cm) and higher BIRADS category were independent predictive factors of upstaging on final pathology. Thus, axillary staging in patients with smaller tumor sizes and lower BI-RADS category may be omitted, with little downstream risk for upstaging.

Error suppression techniques for energy-efficient high-resolution SAR ADCs

The successive approximation register(SAR)is one of the most energy-efficient analog-to-digital converter(ADC)architecture for medium-resolution applications.However,its high energy efficiency quickly diminishes when the target resolution increases.This is because a SAR ADC suffers from several major error source,including the sampling kT/C noise,the comparator noise,and the DAC mismatch.These errors are increasing hard to address in high-resolution SAR ADCs.This paper reviews recent advances on error suppression techniques for SAR ADCs,including the sampling kT/C noise reduction,the noise-shaping(NS)SAR,and the mismatch error shaping(MES).These techniques aim to boost the resolution of SAR ADCs while maintaining their superior energy efficiency.