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1.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
2.
Intraductal papillary mucinous tumor (IPMT) of the pancreas is characterized by slow growth and a relatively favorable prognosis, however, invasive cancer originating in an IPMT is associated with a poor prognosis. Although various parameters in imaging modalities have been advocated to differentiate between benign IPMN and malignant ones, it is not easy to obtain definite diagnosis based on these parameters. Peroral pancreatoscopy (POPS) allows a clear and direct visualization of the pancreatic duct, providing useful information regarding tumor nature in IPMT. The authors have studied the usefulness of POPS in the diagnosis of IPMT. Nevertheless, its usefulness is not necessarily widely accepted and the significance of POPS is still controversial. In this review, the authors intended to address the diagnostic value of POPS and to clarify its role in the diagnosis of IPMT. The authors think treatment of IPMT can be improved by introducing POPS because the determination of surgical procedure as well as the area of resection based on the preoperative diagnosis of the involvement of the main pancreatic duct and branch duct is inevitable. 相似文献
3.
Perianal mucinous adenocarcinoma is a rare tumour which may be associated with long‐standing chronic perianal sepsis. Early diagnosis is challenging and is based on a high index of clinical suspicion and specific histological features. Definitive treatment is surgical, in the form of an abdomino‐perineal resection. We hereby describe a case of a perianal mucinous adenocarcinoma arising from long‐standing recurrent perianal fistula and complement this with a brief review of the literature pertaining in particular to the management of this condition. 相似文献
4.
Clinicopathologlc and mucin histochemical characteristics of 90 cases of ovarian mucinous borderline tumors (MBT) of Intestinal (IMET) and müllerian types (MMBT) were studied to determine whether IMBT and MMBT constitute distinct tumor subtypes. The IMBT (77 cases, 78 lesions) contained goblet cells, absorptive cells and endocrine cells, which represented Intestinal differentiation. The average diameter of IMBT was 13.4 cm. Five patients (6.5%) had stage III disease wtth pseudomyxoma perltonel and one of them died from tumor. Approximately 50% of IMBT demonstrated gastrointestinal characteistics on mucin histochemistry. The MMBT (13 cases, 14 lesions) consisted of mumus columnar cells and eosinophilic cells, with no Intestinal differentiation. MMBT accounted for 15.2% of MBT. MMBT averaged 8.4 cm in diameter, and 29% were associated with endometriosls of the ipsilateral ovary. All patients with MMBT had stage I disease, and none suffered from pseudomyxoma peritonel. All patients whose follow-up data were available were alive and well, without evidence of tumor recurrence. The mucin histochemical findings in MMBT resembled those of noml endocervix. Results of the present study suggest that IMBT and MMBT have different characteristics and constitute distinct subtypes of MBT. 相似文献
5.
S. Hashitani K. Sakurai K. Noguchi J. Natori M. Urade 《Journal of oral pathology & medicine》2004,33(1):59-63
A rare case of mucinous adenocarcinoma with neuroendocrine differentiation of the mandibular ramus is presented. The patient, an 80-year-old man, was referred to our hospital with chief complaint of swelling and pain in the left buccal mucosa. CT and MRI examination showed an osteolytic tumor mass occupying the upper region of the left mandibular ramus. Macroscopically, the excised tumor was a relatively well-defined, solid mass with diffuse bone resorption, measuring 3 cm x 3.2 cm x 3 cm. Microscopical examination showed that the tumor forming glandular structures with abundant mucous production and high cellular atypia. Immunohistochemical studies demonstrated the positive reactivities for pan-keratin, cytokeratin 7, vimentin,alpha-amylase, alpha-smooth muscle actin, neuron-specific enolase, glial fibrillary acid protein, calcitonin, and somatostatin in tumor cells. These findings suggested that the tumor was originated from heterotopic or misplaced salivary gland in the mandible. 相似文献
6.
Kohji Nagata Michiko Horinouchi Miyuki Saitou Michiyo Higashi Mitsuharu Nomoto Masamichi Goto Suguru Yonezawa 《Journal of hepato-biliary-pancreatic sciences》2007,14(3):243-254
In this review article, we demonstrate the mucin expression profile in normal tissue, invasive ductal carcinoma (IDC), two subtypes of intraductal papillary–mucinous neoplasm (IPMN dark cell type and IPMN clear cell type), pancreatic intraepithelial neoplasia (PanIN), and mucinous cystic neoplasm (MCN) of the pancreas. In MUC1, there are various glycoforms, such as poorly glycosylated MUC1, sialylated MUC1, and fully glycosylated MUC1. IDCs showed high expression of all the glycoforms of MUC1. IPMNs dark cell type showed no expression or low expression of all the glycoforms of MUC1. IPMNs clear cell type showed low expression of poorly glycosylated MUC1, but expression of sialylated MUC1 and fully glycosylated MUC1. Expression of MUC2 was negative in IDCs, high in IPMNs dark cell type and low in IPMNs clear cell type. MUC5AC was highly expressed in IDCs, IPMNs dark cell type, and IPMNs clear cell type. MUC6 expression was higher in IPMNs clear cell type than in IDCs and IPMNs dark cell type. Our recent study demonstrated that high expression of MUC4 in IDCs is correlated with a poor outcome for patients. In PanINs, expression of both MUC5AC and MUC6 are an early event, whereas up-regulation of MUC1 is a late event. MCNs do not look as if they will show a specific mucin expression profile according to the literature review. 相似文献
7.
8.
A 35-year-old man complained of a painless enlargement of the right testis. Imaging diagnostic procedures demonstrated a multiloculated cystic tumor, 9 cm in maximal diameter, in the right testis with hydrocele. Orchidectomy specimen showed that the tumor was confined within the testis and separated from the epididymis. The locules of the tumor were lined by single-layered columnar epithelium, intermingled with MUC2 immunopositive goblet and chromogranin-A immunopositive neuroendocrine cells, exhibiting intestinal differentiation. No ciliated cell, teratomatous element or intratubular germ cell neoplasia were seen. Channels of rete testis were compressed peripherally by the tumor but there was no connection with the tumor locules. The tumor was diagnosed as mucinous cystadenoma of the testis. This seems to be the first published case of benign mucinous cystadenoma occurring within the testis. This intratesticular tumor with intestinal differentiation may represent a benign monodermal teratoma. 相似文献
9.
通过78例粘液性和浆液性交界瘤的随访,进一步阐明交界瘤是介于良恶性之间的一类肿瘤。其病理特点为:有一定程度组织结构和细胞形态的异型性,但无明显的间质浸润。其临床分期绝大多数为Ⅰ期。5年存活率分别为84%与78%。加强对交界性瘤这一概念的认识,将有助于临床制定正确的治疗方案。 相似文献