Near-infrared optical imaging of protease activity for tumor detection

PURPOSE: To build and test an optical imaging system that is sensitive to near-infrared fluorescent molecular probes activated by specific enzymes in tumor tissues in mice. MATERIALS AND METHODS: The imaging system consisted of a source that delivered 610-650-nm excitation light within a lighttight chamber, a 700-nm longpass filter for selecting near-infrared fluorescence emission photons from tissues, and a charge-coupled device (CCD) for recording images. The molecular probe was a biocompatible autoquenched near-infrared fluorescent compound that was activated by tumor-associated proteases for cathepsins B and H. Imaging experiments were performed 0-72 hours after intravenous injection of the probe in nude mice that bore human breast carcinoma (BT-20). RESULTS: The imaging system had a maximal spatial resolution of 60 microns, with a field of view of 14 cm2. The detection threshold of the nonquenched near-infrared fluorescent dye was subpicomolar in the imaging phantom experiments. In tissue, 250 pmol of fluorochrome was easily detected during the 10-second image acquisition. After intravenous injection of the probe into the tumor-bearing animals, tumors as small as 1 mm became detectable because of tumor-associated enzymatic activation of the quenched compound. CONCLUSION: Tumor proteases can be used as molecular targets, allowing visualization of millimeter-sized tumors. The development of this technology, probe design, and optical imaging systems hold promise for molecular imaging, cancer detection, and evaluation of treatment.     

Computed assisted detection of interval breast cancers

OBJECTIVES: To examine interval cancer detection rate for a system of computer assisted detection (CAD) and its influence on radiologists' sensitivity/specificity in a screen-like retrospective review situation. MATERIALS AND METHODS: Three screening radiologists reviewed previous screen images of 59 interval cancers mixed with other screening mammograms (ratio 1:5) and non-mixed. Mixed interval cases were interpreted both without and with aid of CAD. RESULTS: CAD detected a number of 14 interval cancers while the three radiologists detected 17, 12 and 11 without and 16, 10 and 13 with CAD. Although CAD specificity was low (38%) no reduction in radiologists' specificity occurred using CAD (73%, 82% and 89% without and 78%, 90% and 92% with CAD). Non-mixed reading increased radiologists' detection rate to 21, 17 and 19 interval cancers respectively. CONCLUSION: Despite sufficiently high sensitivity for CAD alone no increase in radiologist sensitivity (or decrease in specificity) occurred with CAD. Improving CAD specificity, with unaffectedly high sensitivity, should make radiologists more inclined to revise interpretations according to CAD. The potential sensitivity increase, noted when using CAD as a double reader, could be realised in this way.     

计算机辅助检测在乳腺癌X线诊断中的应用

目的评价计算机辅助检测(CAD)系统在乳腺癌X线诊断中的临床应用价值。方法使用CAD系统对136例乳腺癌钼靶X线片进行检测，以手术病理结果为标准对CAD标记结果进行统计分析，并与放射科医生的检测结果进行比较。结果CAD系统对微小钙化的敏感性为93．2％(41／44)，特异性为22．8％(21／92)，准确性为45．6％(62／136)；CAD系统对肿块及结构紊乱病灶敏感性为82．9％(107／129)，特异性为71．4％(5／7)，准确性为82．4％(112／136)。经Kappa检验，CAD系统与放射科医生的检测结果一致性具有显著性意义(Kappa肿块=0．424，P肿块=0．000；Kappa钙化=0．365，P钙化=0．013)。结论CAD系统具有敏感性高、特异性较低的特点。在临床乳腺钼靶X线片的影像诊断中CAD系统可作为辅助检测工具。     

Computer-aided detection applied to breast MRI: assessment of CAD-generated enhancement and tumor sizes in breast cancers before and after neoadjuvant chemotherapy

RATIONALE AND OBJECTIVES: MRI has shown promise in assessing breast cancer patients undergoing neoadjuvant chemotherapy. Computer-aided detection (CAD) for MRI can automatically display tumor enhancement parameters. This study was performed to determine the utility of CAD applied to breast MRI in this patient population. MATERIALS AND METHODS: Fifteen patients with 16 newly diagnosed locally advanced breast cancers were evaluated with MRI before and after neoadjuvant chemotherapy. CAD assessments, including presence or absence of significant enhancement, enhancement profiles, and maximum sizes, were recorded. Pre-chemotherapy and post-chemotherapy enhancement profiles were compared. Sizes were compared to those measured by the radiologist and at final pathology. RESULTS: Prior to chemotherapy, all tumors demonstrated CAD-assessed significant enhancement. Following chemotherapy, 7/16 tumors showed no residual significant enhancement, but all had residual disease at pathology. In those patients with residual enhancement, comparison of the post-chemotherapy to pre-chemotherapy CAD enhancement profiles showed a significant decrease in percentage of washout enhancement (P = 0.0147) in patients with less than 5 mm of residual microscopic disease. Radiologist-measured tumor sizes demonstrated better correlation with sizes at pathology (r = 0.60) than did CAD-generated tumor sizes (r = 0.32). CONCLUSION: CAD may be helpful in assessing changes in MRI enhancement profiles of tumors following chemotherapy. However, CAD-assessed significant enhancement following chemotherapy can be falsely negative for residual malignancy, and CAD tumor sizes are less accurate than those measured by the radiologist in predicting size of residual malignancy. CAD may complement but should not replace the radiologist's assessment of tumors in this patient population.     

乳腺分叶状肿瘤影像表现分析

目的：探讨乳腺分叶状肿瘤(PTB)影像表现特征。方法收集经手术病理证实的 PTB 35例,分析其临床特点及影像特征。结果35例 PTB(36个病灶)中19个良性,8个交界性,9个恶性。X 线表现为卵圆形(16/36)或分叶状肿块(20/36),大部分呈高密度(30/36),边界清晰(28/36),所有病灶均未见钙化、毛刺、皮肤增厚、乳头内陷及腋窝淋巴结肿大。1例 MRI 表现为分叶状肿块,T1 WI 呈等/稍低信号,T2 WI 呈不均匀高信号,DWI 呈稍高信号,动态增强时间-信号曲线为Ⅱ型。结论PTB 的临床及影像学表现具有一定的特点,术前可提示诊断,最终诊断依靠手术病理。     

Performance of computer-aided detection applied to full-field digital mammography in detection of breast cancers

Objective

The aim of this retrospective study was to evaluate performance of computer-aided detection (CAD) with full-field digital mammography (FFDM) in detection of breast cancers.

Materials and Methods

CAD was retrospectively applied to standard mammographic views of 127 cases with biopsy proven breast cancers detected with FFDM (Senographe 2000, GE Medical Systems). CAD sensitivity was assessed in total group of 127 cases and for subgroups based on breast density, mammographic lesion type, mammographic lesion size, histopathology and mode of presentation.

Results

Overall CAD sensitivity was 91% (115 of 127 cases). There were no statistical differences (p > 0.1) in CAD detection of cancers in dense breasts 90% (53/59) versus non-dense breasts 91% (62/68). There was statistical difference (p < 0.05) in CAD detection of cancers that appeared mammographically as microcalcifications only versus other mammographic manifestations. CAD detected 100% (44/44) of cancers manifesting as microcalcifications, 89% (47/53) as no-calcified masses or asymmetries, 88% (14/16) as masses with associated calcifications, and 71% (10/14) as architectural distortions. CAD sensitivity for cancers 1-10 mm was 84% (38/45); 11-20 mm 93% (55/59); and >20 mm 97% (22/23).

Conclusion

CAD applied to FFDM showed 100% sensitivity in identifying cancers manifesting as microcalcifications only and high sensitivity 86% (71/83) for other mammographic appearances of cancer. Sensitivity is influenced by lesion size. CAD in FFDM is an adjunct helping radiologist in early detection of breast cancers.     

Unusual breast cancers: useful clues to expanding the differential diagnosis

Invasive ductal carcinoma and ductal carcinoma in situ account for about 85% of breast cancers. Unusual breast neoplasms may be broadly divided into invasive lobular carcinoma, well-differentiated subtypes of invasive ductal carcinoma, cancers of stromal origin, and metastatic neoplasms. Clues are often present in imaging characteristics, patient demographics, and/or clinical features that may suggest that the finding is not the usual type of breast cancer. Some rare malignancies also provide specific clues to their diagnosis. This review provides an overview of unusual and a few rare malignant breast neoplasms, highlighting particular or specific clinical or imaging findings that will enable residents to expand their differential diagnosis of breast lesions beyond invasive ductal carcinoma.     

盆部孤立性纤维瘤的影像学表现与鉴别诊断

目的 探讨盆部孤立性纤维瘤(PSFT)的CT及MRI特点,以提高对该病的认识.方法 回顾性分析6例经手术病理证实的PSFT的CT、MRI表现,并与病理对照.结果 6例中3例位于直肠膀胱间隙,直肠右旁间隙、骶骨前间隙、右侧腹股沟区各1例.3例病灶单发,3例多发.5例边界清楚,1例不清.肿块呈分叶状3例,圆形/椭圆形2例,不规则形1例.平均最大径约14.7 cm(4.9～35 cm).CT平扫密度不均匀伴有斑片状低密度区,未见钙化、出血.MRI T1WI呈等信号,2例T2WI呈稍高信号,1例呈高信号,2例散在长T1、长T2信号区,病灶内及周围见点线状血管流空信号.3例增强扫描动脉期明显不均匀强化,瘤内及周围见增粗血管强化;静脉期和延迟期呈进行性或持续强化,且强化范围扩大,内有斑片状无强化区.结论 当盆部病变表现为单发或多发肿块,边界清楚,密度或信号不均匀,特别是增强后动脉期明显不均匀强化、静脉期和延迟期持续强化时,应考虑到PSFT的可能.     

乳腺癌新辅助化疗疗效的基因表达谱分析

目的 分析乳腺癌新辅助化疗前活检组织的基因表达谱数据,筛选与T/FAC(多西他赛、氟尿嘧啶、多柔比星和环磷酰胺)或T/FEC(多西他赛、氟尿嘧啶、表柔比星和环磷酰胺)新辅助化疗方案治疗有效性显著相关的基因.方法 从国际上已发表的相关文献中检索并获取乳腺癌基因表达谱数据,按照统一的新辅助化疗方式进行数据筛选,最终保留4个符合要求的数据集,共844个样本.其中样本按照化疗效果分为病理完全缓解(pCR)和残留浸润性癌(RD)两类.分析两组样本差异表达的基因,探讨其表达水平的变化与化疗疗效的相关性. 结果 通过分析,我们分别在4个数据集中找出显著差异的基因(校正P<0.05),按照表达水平的高低,分为pCR组相比RD组高表达的基因和低表达的基因两组.最后,将4个数据的结果整合,得到在4个数据集中同时高表达或低表达的基因,分别为34和42个.基于交集的差异表达基因,对样本进行无监督聚类,发现pCR和RD两组倾向性地分别富集在两类(一致性检验,P<0.05).结论 分析得到的76个差异表达基因与乳腺癌新辅助化疗疗效有关,可能成为新的化疗疗效预测标志物.     

Mode of detection matters: Differences in screen-detected versus symptomatic breast cancers

ObjectiveAlthough extensive analyses evaluating screening mammography for breast cancer have been published, some utilized databases do not distinguish between modes of detection, which confounds the conclusions made about the impact of screening mammography.MethodsA retrospective cohort study of women at our institution with pathologically-proven breast cancer from January 2015 to April 2018 was conducted. Subjects were categorized by their mode of diagnosis: screening or non-screening. Patient demographics, tumor characteristics, and treatments were compared between detection methods using Wilcoxon rank-sum test for continuous variables and chi-squared or Fisher's exact test.Results1026 breast cancers were analyzed. 80.8% of screen-detected breast cancers were invasive. Compared to symptomatically detected cancers, screen-detected were smaller (median size 8 mm vs. 15 mm, p < 0.001), less invasive (80.8% vs. 94.3), had a lower pathologic grade (29% grade 3 vs. 45.7%, p < 0.001), a lower clinical stage, and less aggressive histology (51.9% low Ki67 vs. 30.5%, and 88.2% HER2 negative vs. 76.6%, p < 0.001). Screen-detected cancers were less likely to have extramammary disease (13.2% positive lymph nodes vs. 34.0% and 0.4% distant metastases vs. 6.9%, p < 0.001). Women with screen-detected cancers were more likely to undergo conservative treatment (74.8% underwent lumpectomy vs. 59.9%, and 80.0% received no chemotherapy vs. 51.3%, p < 0.001).ConclusionIn this study, while the vast majority of screen-detected cancers were invasive, they were more likely to be smaller, less aggressive, and a lower pathologic grade and clinical stage. Furthermore, women with screen-detected cancers were less likely to have extramammary disease and more likely to undergo conservative treatment.     

Imaging features of aggressive angiomyxoma

AIM: To describe the imaging features of aggressive angiomyxoma in a rare benign mesenchymal tumour most frequently arising from the perineum in young female patients. MATERIALS AND METHODS: We reviewed the computed tomography (CT) and magnetic resonance (MR) imaging features of patients with aggressive angiomyxoma who were referred to our hospital. The imaging features were correlated with clinical information and pathology in all patients. RESULTS: Four CT and five MR studies were available for five patients (all women, mean age 39, range 24-55). Three patients had recurrent tumour at follow-up. CT and MR imaging demonstrated a well-defined mass-displacing adjacent structures. The tumour was of low attenuation relative to muscle on CT. On MR, the tumour was isointense relative to muscle on T1-weighted image, hyperintense on T2-weighted image and enhanced avidly after gadolinium contrast with a characteristic "swirled" internal pattern. MR imaging demonstrates the extent of the tumour and its relation to the pelvic floor. Recurrent tumour has a similar appearance to the primary lesion. CONCLUSION: The MR appearances of aggressive angiomyxomas are characteristic, and the diagnosis should be considered in any young woman presenting with a well-defined mass arising from the perineum.     

脊柱恶性血管源性肿瘤的影像表现及鉴别诊断

目的：探讨脊柱恶性血管源性肿瘤的影像表现。方法：对9例经病理确诊的脊柱恶性血管源性肿瘤的CT和MRI表现进行回顾性分析并总结其影像特点。结果：9例中2例为血管肉瘤,7例为上皮样血管内皮瘤;5例病变位于颈椎,3例位于胸椎,1例位于腰椎;4例为单中心、2例为多中心病变,3例累及相邻椎体。CT 表现：9例均显示溶骨性骨破坏、周围骨皮质不完整,其中5例肿瘤内部可见残存骨嵴。MRI 表现：肿瘤于 T1 WI 呈低信号,于 T2 WI 呈混杂信号（3例）、中等信号（2例）或高信号（4例）;增强扫描示肿瘤呈明显强化4例 ,呈中等强化 1例。结论：恶性血管源性肿瘤主要影像表现为单中心性或多中心溶骨性骨破坏、多位于颈胸椎,部分具有血管瘤的特点,容易导致脊柱压缩变形。     

高频超声鉴别诊断乳腺肿瘤的临床价值

随着彩色多普勒(CDFI)技术迅速发展以及高频探头的广泛应用,超声检查乳腺疾病已成为临床早期诊断乳腺癌的重要方法之一.能量图(CDE)及三维血管成像技术(3DCPA)具有更高的血流敏感性,进一步提高了诊断的准确率.现将我院2001年以来高频超声诊断的48例乳腺肿瘤病例总结如下.     

超声对乳腺叶状肿瘤与纤维腺瘤的鉴别诊断价值

乳腺叶状肿瘤（phyllodes tumor of the breast,PTB）以往曾称为叶状褒肉瘤,2003年WHO将其命名为叶状肿瘤,该肿瘤大部分为良性。其临床及超声表现与纤维腺瘤（breast fibroadenoma,BY）较为相似,影像学鉴别诊断较为困难。     

Imaging phenotypes of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality worldwide. COPD is defined by irreversible airflow obstruction. It is a heterogeneous disease affecting the airways and/or the parenchyma with different severity during the course of the disease. These different aspects of COPD can be addressed by imaging using a combination of morphological and functional techniques. Computed tomography (CT) is the technique of choice for morphological imaging of the lung parenchyma and airways. This morphological information is to be accomplished by functional information about ventilation and perfusion, mainly provided by magnetic resonance imaging (MRI). The comprehensive diagnostic possibilities of CT complemented by MRI will allow for a more sensitive detection, phenotype-driven characterization, and dedicated therapy monitoring of the disease.     

Assessment of CAD-generated tumor volumes measured using MRI in breast cancers before and after neoadjuvant chemotherapy

Objective

To evaluate inter-observer agreement and the predictive value of tumor size measurements using MRI for breast cancer under neoadjuvant chemotherapy (NAC) by comparing the measurements of the longest diameters (LD), total enhanced volumes (TEV) and washout volumes (WOV).

Methods

Thirty-seven female breast cancer patients were prospectively enrolled from August 2008 to October 2010. Two of these patients had locally advanced disease. MRI examinations were acquired within 2 weeks before and after NAC. Interim scans were also conducted in 30 patients. Tumor resection was undertaken within 2 weeks after the cessation of NAC. MRI images were independently measured for LD, TEV and WOV by two experienced radiologists. Inter-observer agreement was evaluated using concordance correlation coefficients (CCCs). Tumor sizes after NAC were evaluated relative to their initial sizes for early prediction of a pathological complete response (pCR).

Results

The CCCs were 0.93 (CI: 0.90–0.95) for LD, 0.98 (CI: 0.97–0.98) for TEV and 0.99 (CI: 0.991–0.996) for WOV. All measurements had high inter-observer agreement, but the CCCs were significantly increased in the aforementioned order (P < 0.0001). WOV measured after the completion of chemotherapy had significant discriminating ability (P = 0.0056) when evaluated using receiver operating characteristic analysis, and was found to be superior to LD (P = 0.045). The average WOV size was significantly smaller in pCR cases than in non-pCR cases (P = 0.016).

Conclusion

Computer-aided detection-generated tumor volumes had significantly higher inter-observer concordance than conventional LD measurements. WOV measurements had the highest concordance, and WOV could better predict pCR after NAC at smaller tumor sizes.