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131.
Rosalind P. Candelaria Palita Hansakul Alastair M. Thompson Huong Le-Petross Vicente Valero Roland Bassett Monica L. Huang Lumarie Santiago Beatriz E. Adrada 《American journal of surgery》2018,215(4):693-698
Background
To determine the cancer yield of stereotactic biopsy of suspicious calcifications identified within 24 months after breast conservation therapy (BCT).Methods
Retrospective review of stereotactic biopsies performed during 2009–2013 for suspicious calcifications in the ipsilateral breast of patients who completed BCT.Results
94/2773 (3.4%) had stereotactic biopsies for suspicious calcifications in the ipsilateral breast; 7/94 (7.4%) had DCIS (6) or invasive (1) cancer; 5/7 occurred in the same breast quadrant as the primary. All 7 originally had negative surgical margins (≥2 mm); 6 received whole breast irradiation, and 2 received adjuvant chemotherapy + endocrine therapy. Median time to detection was 11 months (range, 6–20 months). There was a strong association between calcification morphology (particularly pleomorphic) and likelihood of malignancy (p = 0.008).Conclusions
Stereotactic biopsy of calcifications identified within 24 months post-BCT has a 7% cancer yield. Tissue biopsy should be performed rather than imaging followup alone when breast calcifications have suspicious morphology. 相似文献132.
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Factors impacting the accuracy of intra‐operative evaluation of sentinel lymph nodes in breast cancer 下载免费PDF全文
Catherine L. Akay MD Constance Albarracin MD Tiffany Torstenson DO Roland Bassett MS Elizabeth A. Mittendorf MD PhD Min Yi MD PhD Henry M. Kuerer MD PhD Gildy V. Babiera MD Isabelle Bedrosian MD Kelly K. Hunt MD Rosa F. Hwang MD 《The breast journal》2018,24(1):28-34
Sentinel lymph node dissection (SLND) is a standard axillary staging technique in breast cancer and intraoperative sentinel lymph node (SLN) assessment is important for decision‐making regarding additional treatment and reconstruction. This study was undertaken to investigate clinicopathologic factors impacting the accuracy of intraoperative SLN evaluation. Records of patients with clinically node‐negative, invasive breast cancer who underwent SLND with frozen section intraoperative pathologic evaluation from 2004 to 2007 were reviewed. Intraoperative SLN assessment results were compared to final pathology. Patients with positive SLNs that were initially reported as negative during intraoperative assessment were considered false negative (FN) events. Primary tumor histology, grade, receptor status, size, lymphovascular invasion (LVI), multifocality, neoadjuvant chemotherapy or hormonal therapy, number of SLNs retrieved, and SLN metastasis size were evaluated. The study included 681 patients, of whom 262 (38%) received neoadjuvant therapy. There were 183 (27%) patients who had a positive SLN on final pathology, of whom 60 (33%) had FN events. On univariate analysis, lobular histology, favorable histology, absence of LVI and micrometastasis were associated with a higher FN rate. On multivariate analysis, favorable and lobular histology and micrometastasis were independent predictors of FN events whereas LVI and receipt of neoadjuvant therapy were not statistically significant predictors. The accuracy of intraoperative SLN evaluation for breast cancer is affected by primary tumor histology and size of the SLN metastasis. There was no significant association between neoadjuvant therapy and the FN rate by intraoperative assessment. This information may be helpful in counseling patients about their risk for a FN intraoperative SLN assessment and for planning for immediate breast reconstruction in patients undergoing mastectomy. 相似文献
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Cuzzocreo JL Yassa MA Verduzco G Honeycutt NA Scott DJ Bassett SS 《Human brain mapping》2009,30(4):1271-1278
Several studies have shown marked differences in the neural localization of language functions in the brains of left-handed individuals when compared with right-handers. Previous experiments involving functional lateralization have demonstrated cerebral blood flow patterns that differ concordantly with subject handedness while performing language-related tasks. The effect of handedness on function in specific stages of memory processing, however, is a largely unexplored area. We used a paired-associates verbal memory task to elicit activation of neural areas related to declarative memory, examining the hypothesis that there are differences in activation in the medial temporal lobe (MTL) between handedness groups. 15 left-handed and 25 right-handed healthy adults were matched for all major demographic and neuropsychological variables. Functional and structural imaging data were acquired and analyzed for group differences within MTL subregions. Our results show that activation of the MTL during declarative memory processing varies with handedness. While both groups showed activation in left and right MTL subregions, the left-handed group showed a statistically significant increase in the left hippocampus and amygdala during both encoding and recall. No increases in activation were found in the right-handed group. This effect was found in the absence of any differences in performance on the verbal memory task, structural volumetric disparities, or functional asymmetries. This provides evidence of functional differences between left-handers and right-handers, which extends to declarative memory processes. 相似文献
139.
Beliveau A Bassett E Lo AT Garbe J Rubio MA Bissell MJ Campisi J Yaswen P 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(11):4431-4436
Ectopically expressed hTERT enables p16(INK4A)(-) human mammary epithelial cells to proliferate in the absence of growth factors, a finding that has led to the hypothesis that hTERT has growth regulatory properties independent of its role in telomere maintenance. We now show that telomerase can alter the growth properties of cells indirectly through its role in telomere maintenance, without altering growth stimulatory pathways. We find that telomere dysfunction, indicated by 53BP1/phosphorylated histone H2AX foci at chromosome ends, is present in robustly proliferating human mammary epithelial cells long before senescence. These foci correlate with increased levels of active p53. Ectopic expression of hTERT reduces the number of foci and the level of active p53, thereby decreasing sensitivity to growth factor depletion, which independently activates p53. The continuous presence of hTERT is not necessary for this effect, indicating that telomere maintenance, rather than the presence of the enzyme itself, is responsible for the increased ability to proliferate in the absence of growth factors. Our findings provide a previously unrecognized mechanistic explanation for the observation that ectopically expressed hTERT conveys growth advantages to cells, without having to postulate nontelomeric functions for the enzyme. 相似文献
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