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1.
目的评估并比较基于不同机器学习算法建立的乳腺癌超声影像组学预测模型的诊断性能。 方法回顾性收集2017年1月至2019年4月就诊皖南医学院第一附属医院、有明确病理结果的乳腺肿块病例828例,以2018年8月31日为节点将其分为训练集(526例)和验证集(302例),提取肿块的超声影像组学特征并进行特征筛选,运用k最近邻(kNN)、逻辑回归(LR)、朴素贝叶斯(NB)、随机森林(RF)和支持向量机(SVM)5种机器学习算法分别建立预测模型,使用重复交叉验证方法做内部验证,计算比较各模型的敏感度、特异度、阳性预测值(PPV)和阴性预测值(NPV),并实施外部验证,绘制ROC曲线并比较ROC曲线下面积(AUC)以评价模型的鉴别诊断性能,绘制校准曲线评价模型校准度。 结果从提取的109个影像组学特征中筛选出19个特征建立了5种机器学习算法模型。在内部验证中,5种模型的敏感度、特异度、PPV、NPV比较,总体差异均有统计学意义(P均<0.001)。LR模型的特异度、PPV、NPV中位数分别为0.769、0.816、0.778,3项指标均高于其他4种模型;敏感度中位数为0.824,高于kNN、RF和SVM模型。此外,SVM模型的特异度、PPV、NPV中位数分别为0.706、0.774、0.759,虽均低于LR模型,但均高于其他3种模型。在外部验证中,LR、SVM、RF、kNN和NB的AUC依次为0.890、0.832、0.821、0.746和0.703,其中LR与SVM的AUC差异有统计学意义(P=0.012);此外,各模型在校准性能上表现并不一致,LR和SVM模型的校准曲线显示乳腺癌实际概率与预测概率之间的一致性较好。 结论以超声影像组学特征为基础,运用不同机器学习算法建立的乳腺癌超声预测模型,均表现出较高的诊断性能,其中LR模型表现最为突出;选择合适的机器学习算法有助于进一步提高预测模型的诊断性能,提供更加准确的量化预测结果。  相似文献   
2.
ObjectiveRole of Magnetic Resonance Imaging (MRI) in diagnosis of tuberculous tubo-ovarian (TO) mass.MethodsMRI was performed on 33 patients of tuberculous TO mass of female genital tuberculosis (FGTB).ResultsMean age, BMI, and parity was 27.5 ± 4.2 years, 22.7 ± 3.6 kg/m2, and 0.27 ± 0.13. All patients (100%) had infertility; primary infertility (72.72%) and secondary infertility (27.23%) with mean 5.8 years. Abdominal/pelvic pain 33 (100%) cases, abdominal lump 4 (12.12%), adnexal mass 33 (100%). MRI findings showed pelvic masses 33 (100%), bilateral TO masses 11 (33.33%), cystic lesion 4 (12.12%), solid cystic lesion 3 (9.09%) with bilateral pyosalpinx 1 (3.3%), homogeneous content with ascites 1 (3.03%), rim enhancing lesion abutting pelvic wall in 1 (3.03%). Right adnexal mass 11 (33.33%), right adnexal cyst 2 (6.06%), right adnexal cystic mass in 1 (3.03%), right sided complex TO mass 1 (3.03%), right sided hydrosalpinx in 1 (3.03%) case, right sided TO mass in 4 (12.12%) cases and right sided para-ovarian cyst in 2 (6.06%). Left sided adnexal mass was seen in 11 (33.33%), cystic lesion in 1 (3.03%), ovarian cyst in 3 (9.09%) cases, left sided hydrosalpinx in 2 (6.06%), left ovarian cyst 2 (6.06%) cases, left sided ovarian cyst with encysted ascites 1 (3.03%) case and with left sided paraovarian cyst 2 (6.06%) case. Miscellaneous finding were generalised ascites (6.06%), encysted ascites (3.03%), pelvic (1; 3.03%) and mesenteric lymphadenopathy 1 (3.03%). Incidental finding were fibroid 3 (9.09%) and adenomyosis 1 (3.03%) case.ConclusionMRI appears to be useful diagnostic modality for tuberculous TO masses where differential diagnosis is malignancy but molecular diagnosis remains the gold standard.  相似文献   
3.
目的:系统评价具有软坚散结功效的中药复方治疗甲状腺结节的疗效和安全性。方法:检索具有软坚散结功效的中药复方治疗甲状腺结节的RCTs,进行方法学质量评价并提取数据,用Revman5.3软件进行Meta分析。结果:纳入34篇临床随机对照试验。分析结果显示中药+西药组vs西药组、中药组vs西药组,在总有效率、甲状腺结节直径缩小方面差异有统计学意义。结论:中药治疗甲状腺结节疗效优于西药治疗,且不良反应少,相对安全。  相似文献   
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Purpose/aim: To focus on current aspects of primary thyroid lymphoma (PTL), which is a rare clinical entity usually manifested by a rapidly growing mass in the neck that can cause pressure symptoms.

Materials and Methods: Relevant papers in PubMed published through June 2017 were selected to track updated information about PTL with an emphasis on diagnosis and novel therapeutic management.

Results: The most frequent cases include non-Hodgkin lymphoma derived from B-cells, mainly diffuse large B-cell lymphoma (DLBCL) followed by mucosa-associated lymphoid tissue (MALT) lymphoma or a mixed type. Other subtypes are less common. Lymphomas derived from T-cells and Hodgkin lymphomas are extremely rare. Hashimoto's autoimmune thyroiditis has been implicated as a risk factor for lymphoma. At the molecular level, the Wnt5a protein and its receptor Ror2 are involved in the course of the disease. Ultrasonography, fine needle aspiration (FNA) biopsy, and core or open biopsy combined with new diagnostic facilities contribute to an accurate diagnosis. An increased potential exists for a cure without the need for a radical surgical procedure. Modern chemoradiation therapy plus the monoclonal antibody rituximab, which acts against CD20, have limited the need for surgical interventions and provide an excellent outcome in most cases. However, some cases have resulted in treatment failure or recurrence.

Conclusions: A multidisciplinary approach must be used to define the management policy in each case. Future efforts by researchers are likely to be focused on the molecular level.  相似文献   

8.
Ovarian cysts are common in pregnancy, more so with the increase in routine antenatal use of ultrasonography. The majority of ovarian cysts in pregnancy are benign and resolve spontaneously. It is rare to diagnose malignant ovarian tumours during pregnancy. Imaging with ultrasonography is the first line investigation of choice and the use of International Ovarian Tumor Analysis (IOTA) group rules of ultrasonographic appearances of ovarian lesions can help identify benign and malignant lesions more accurately. MRI is also safe to use in pregnancy to better delineate ovarian lesions. Simple cysts <6 cm can be safely managed conservatively, with surgery reserved for larger, symptomatic cysts or those suspicious of malignancy. Ovarian cysts can be managed laparoscopically between 14 and 16 weeks gestation but require advanced laparoscopic skills. Image guided aspiration of benign ovarian cysts remains an option but is associated with high recurrence rates and risk of spillage, a disadvantageous outcome in cases subsequently shown to be malignant.  相似文献   
9.

Objective

To study the clinical and histopathological presentation of ovarian masses.

Method

Retrospective analysis of 205 cases from May 2009 to June 2013.

Results

Incidence of ovarian masses was 6.9 %. Among 205 cases, 68 % were neoplastic. Among the neoplasms, 87.8 % were benign, 10 % malignant, and 2.2 % borderline. Mean ages of malignant and benign neoplasm were 41 and 39 years, respectively. 42.9 % malignant tumors presented with non-specific abdominal and constitutional symptoms. Serous cystadenoma was the commonest benign tumor (67 %) followed by Mucinous (19 %) and Dermoid (11.6 %). Most common malignant ovarian tumor was Serous cystadenocarcinoma (42.9 %). Out of the malignant cases, all were primary except one secondary deposit from Non-Hodgkin’s Lymphoma. Only 28.6 % presented at stage I, remaining presented at stage III/IV.

Conclusion

Ovarian neoplasms have twice the incidence of non-neoplasms. Mean age of malignant tumors is decreased. Rising trend in Mucinous cystadenoma is noted.
  相似文献   
10.
附件包块病因复杂多样,相应的临床决策千差万别。因此,对附件包块性质的预判是临床诊断的首要任务,也是临床工作的难点和要点。CA125是鉴别附件包块良恶性的最常见指标,但影响因素多,不建议单独用于绝经前女性。人附睾蛋白4(HE4)特异度高,联合CA125可显著提高附件包块良恶性鉴别诊断的准确率。针对附件包块拟行手术的患者,推荐应用卵巢恶性肿瘤风险模型(ROMA)和恶性肿瘤风险指数(RMI)进行评估,高危者应转诊到妇科肿瘤专科。  相似文献   
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