Assessment of Papillary Thyroid Carcinoma with Ultrasound Examination.

Ultrasound examination of the thyroid is useful for preoperative assessment of thyroid nodules including papillary thyroid carcinoma. The examination mainly is to determine the malignant potential of thyroid nodule(s). There are different systems to predict malignant potential in the thyroid nodules and cervical lymph nodes by ultrasound. Ultrasound is used in conjunction with fine-needle aspiration to diagnosis papillary thyroid carcinoma. It is used as guidance to locate the sites to obtain the samples for diagnosis and research in papillary thyroid carcinoma.

Minimal residual disease assessment of papillary thyroid carcinoma through circulating tumor cell-based cytology.

The overall estimated risk of recurrence after an apparently complete thyroid cancer resection ranges from <1% to 55%, and the high-quality pathology report is crucial for proper risk stratification. The neck ultrasound (US) and serum thyroglobulin (Tg) and anti-Tg antibody (TgAb) assays are the mainstays for Differentiated Thyroid Cancer (DTC) follow-up. However, the neck US includes a high frequency of nonspecific findings and despite the serum, Tg unmasks the presence of thyrocytes, it is not discriminating between normal and malignant cells. In this study, to improve post-surgery follow-up of minimal residual disease in papillary thyroid cancer (PTC) patients, blood-derived cytology specimens were evaluated for the presence of circulating tumor cells (CTCs). The presence of CTCs of thyroid origin was confirmed by cytomorphological and tissue-specific antigens analysis (Thyroid Transcription Factor-1/TTF-1 and Tg) and proliferative profile (percentage of cells in S-phase). Our data revealed an unfavorable' prognostic risk in patients with >5% CTCs (p = 0.09) and with >30% S-phase cells at baseline (p = 0.0015), predicting ≤1 year relapsing lesion event. These results suggest a new intriguing frontier of precision oncology forefront cytology-based liquid biopsy.

Sonographic assessment of minor extrathyroidal extension of papillary thyroid microcarcinoma involving the posterior thyroid capsule.

OBJECTIVES: This study aimed to determine sonographic features and clinical significance of minor extrathyroidal extension (ETE) to the posterior thyroid capsule in papillary thyroid microcarcinoma (PTMC) patients. METHODS: We retrospectively reviewed the records of 506 PTMC patients consisting of 151 patients with minor ETE and 355 patients without ETE. Significant clinicoradiologic features associated with ETE were identified by logistic regression analyses. The diagnostic performance of sonographic features, including the presence of capsular abutment, capsular abutment degree (< 25%, 25-50%, ≥ 50%), and protrusion, were assessed for the diagnosis of posterior minor ETE. Interobserver agreement was calculated. RESULTS: PTMC patients with posterior minor ETE were more likely to have lymphovascular invasion and lateral neck lymph node metastasis (OR = 2.636, 95%CI: 1.754, 3.963 and OR = 2.897, 95%CI: 1.069, 7.848). Regarding the diagnostic performance, the capsular abutment yielded the highest sensitivity (81.5%), followed by ≥ 25% abutment, protrusion, and ≥ 50% abutment (57.0%, 21.9%, and 4.6%, respectively), with similar levels of diagnostic accuracy (71.3-75.1%). The specificity was highest for the sonographic feature of ≥ 50% abutment (99.7%), followed by protrusion, ≥ 25% abutment, and capsular abutment (97.8%, 82.0%, and 68.7%, respectively). Abutment assessment had a moderate interobserver agreement (K = 0.705), and abutment degree and protrusion assessment had a fair and slight interobserver agreement (K = 0.553 and 0.287). CONCLUSIONS: Sonographic features of posterior capsular abutment are sensitive and reliable for diagnosis of posterior minor ETE and are associated with lymphovascular invasion and lateral neck lymph node metastasis in PTMC patients. The assessment of posterior minor ETE is important for considering candidates for active surveillance among PTMC patients. KEY POINTS: • PTMC patients with posterior minor ETE were more likely to have lymphovascular invasion and lateral neck lymph node metastasis. • Sonographic features of posterior capsular abutment are sensitive and reliable for the diagnosis of posterior minor ETE. • The assessment of posterior minor ETE is important for considering candidates for active surveillance among PTMC patients.

Cost-effectiveness of computed tomography nodal scan in patients with papillary thyroid carcinoma.

OBJECTIVES: This study evaluates the cost-effectiveness of ultrasound (US) only; computed tomography (CT) only; and combined US-CT in a base-case that underwent total thyroidectomy for a newly diagnosed papillary thyroid carcinoma (PTC) (scenario I) or surgery for recurrent disease (scenario II). MATERIALS AND METHODS: Markov chain model was developed comparing the above modalities. Follow-up time was set as 10 years. Costs and probabilities values are obtained from literature and the National Cancer Database. RESULTS: Nodal mapping of the central compartment in both primary and recurrent PTC scenarios demonstrated combined utilization of preoperative US and CT is preferred over the use of US or CT separately; the final incurred management cost was [scenario I: U.S.$10,548.25 - scenario II: U.S.$11.197.88] and effectiveness was [scenario I: 6.875 Quality-adjusted-life-year (QALY) - scenario II: 6.871 QALY]. Nodal mapping of the lateral compartments favored US alone as the cost-effective modality in both scenarios; the final incurred management cost was [scenario I: U.S.$10,716.60 - scenario II: U.S.$11,247.92] and effectiveness was [scenario I: 6.879 QALY - scenario II: 6.883 QALY]. Sensitivity analysis demonstrated that for combined utilization of US and CT scans to remain cost-effective, the cost of a CT scan should be less than U.S.$1,127.54. CONCLUSIONS: Based on the model, combined utilization of US and CT is cost-effective in nodal mapping patients with PTC.

Using 2-dimensional color superb microvascular imaging vascularization index technique in the assessment of thyroid surgical bed.

AIM: The purpose of this study was to investigate the effectiveness of the vascularization index (VI) obtained using color superb microvascular imaging (cSMI) technique in the assessment of thyroid surgical bed for remnant thyroid tissue (RTT). MATERIAL AND METHODS: We evaluated the thyroid surgical bed of 65 patients who had underwent total thyroidectomy (TT) due to papillary carcinoma (PC) using thyroid scintigraphy and cSMI. Color SMI was also performed for the examination of the thyroid parenchyma of 39 healthy asymptomatic participants. VI measurements were performed by manually drawing the contours of the RTT in those with remnant thyroid, the thyroid surgical bed in the patients' group without remnant thyroid, and normal thyroid parenchyma in the control group, using the free region of interest (ROI) with 2-dimensional color SMI VI (2DcSMIVI) mode. The volume of ROI was measured and echogenicity was evaluated. The quantitative 2DcSMIVI values of the surgical bed with RTT (Group A), the surgical bed without RTT (Group B) and normal thyroid of healthy asymptomatic participants (Group C) were compared. RESULTS: The mean 2DcSMIVI values of Group A was significantly higher than Group B and C (p=0.001). The presence of RTT can be diagnosed with 89.1% sensitivity and 87.5% specificity when 1.75 2DcSMIVI is designated as the cut-off value. CONCLUSION: The 2DcSMIVI is an effective imaging technique that can be used for the diagnosis of RTT.

[Ultrasonographic assessment and differentiation of spontaneous degenerating cystic thyroid nodules and papillary thyroid carcinomas].

Objective: To analyze the features of degenerating cystic thyroid nodules (DCTN) on conventional ultrasound and contrast-enhanced ultrasound (CEUS), and to explore the differentiation between DCTN and papillary thyroid carcinomas (PTC). Methods: A total of 46 DCTN (39 cases, including 12 males and 27 females, with an age range of 25 to 76 years) and 36 PTC (32 cases, including 8 males and 24 females, with an age range of 23 to 68 years) diagnosed via fine- needle aspiration (FNA) or surgery from February 2019 to January 2020 in the First Affiliated Hospital of Nanchang University were enrolled. The size, shape, margin, echogenicity, presence of shadowing, calcification and vascularity of DCTN and PTC were retrospectively evaluated, and 28 DCTN and 30 PTC underwent CEUS were separately analyzed and compared.The t test, χ² test or Fisher's exact test were implemented to compare the features of ultrasound among the two groups. The binary Logistic regression test was performed to determine whether the feature whose difference was statistically significant was an independent predictive risk factor. Results: A univariate analysis indicated that DCTN more frequently showed wider-than-tall shapes, marked hypoechogenicity, well-defined margin and no or dot-lined enhancement (wider-than-tall shapes: 36 vs. 17, χ2=8.511; well-defined margin: 30 vs. 15, χ2=4.523; marked hypoechogenicity: 27 vs. 9, χ2=9.310; no or dot-lined enhancement: 24 vs. 3, χ2=33.369; all P＜0.05). A multivariate analysis demonstrated that wider-than-tall shapes, well-defined margin and marked hypoechogenicity were independent predictors for DCTN (OR values were 5.204, 3.134 and 5.042, P values were 0.003, 0.031, and 0.003, respectively). Among 28 DCTN, 15 showed a decrease in mean maximum diameter (24.3±11.4 mm) with a mean time span of (18.6±10.5) months between the presence and absence of suspicious ultrasound features. Conclusions: Compared with PTC, DCTN shows the ultrasound characteristics of wider-than-tall shapes, well-defined margin, marked hypoechogenicity and no or dot-lined enhancement pattern. Ultrasound follow-up can help to identify spontaneous DCTN.

Interobserver Agreement of Planar and SPECT Tc99m-MIBI Scintigraphy for the Assessment of Hypofunctioning Thyroid Nodules.

INTRODUCTION: Thyroid scintigraphy with 99mTc-methoxyisobutylisonitrile (MIBI) is a helpful tool for the risk stratification of thyroid nodules (TN). Whereas a nodule with low or hypointense MIBI uptake has a low risk for malignancy, a hyperintense uptake may indicate a malignant nodule, which requires surgical resection. The appropriate diagnostic or therapeutic regimen of an isointense nodule with an uptake similar to the paranodular tissue is discussed controversially. Aim of this study was to assess the interobserver agreement (IA) for the assignment of TN to the three categories: hypo-, iso-or hyperintense. METHODS: Retrospective analysis of planar and SPECT images of MIBI scintigraphy was performed in 36 randomly selected patients with hypofunctioning TN and histological diagnosis. Four observers with different levels of experience in MIBI-scintigraphy analyzed MIBI uptake and assigned the nodules to the appropriate category. To assess the IA, Fleiss' Kappa was calculated. RESULTS: The study cohort included 11 patients with papillary thyroid carcinoma (diameter 20.3 mm) and 25 patients with benign nodules (diameter 24.8 mm). The IA for all nodules using planar images was 0.76 compared to 0.80 for SPECT images. The IA was better in the subgroup of malignant nodules for planar images as well as SPECT images (Kappa 0.91 and 0.90, respectively) compared to benign nodules (0.65 and 0.76, respectively). Using SPECT images, only one thyroid carcinoma presented with hypointense uptake, the remainder with hyper- or isointense uptake. In contrast, benign nodules were found in all categories. CONCLUSION: MIBI scintigraphy shows a good IA for the interpretation of thyroid carcinoma. The IA is further improved if MIBI scintigraphy is performed in SPECT technique.

Ultrasound Risk Assessment Combined with Molecular Markers of Galectin-3, c-MET, HBME-1 and CK19 for Diagnosis of Malignant and Benign Thyroid Nodules.

To investigate the effect of ultrasound combined with expression of Galectin-3, c-Met, HBME-1 and CK19 in differentiating malignant from benign thyroid nodules. Forty-six patients with thyroid nodules were studied with ultrasound and immunohistochemical staining of excised thyroid nodules. The data were classified and compared. The immunohistochemical staining revealed 8 benign and 41 malignant thyroid lesions. In ultrasound risk assessment, the malignancy risk was low in four nodules, medium in five and high in 37 with lymphatic metastasis in 26. A significant (P < 0.05) association existed in the expression of Galectin-3 with nodule boundary and lymphatic metastasis, in HBME-1 with nodule micro-calcification and in c-Met with nodule micro-calcification and lymphatic metastasis. CK19 expression was not significantly (P > 0.05) associated with any of ultrasound features of nodule. Galectin-3, c-Met, HBME-1 and CK19 were significantly (P < 0.05) different in malignant and benign thyroid lesions, with a significant (P < 0.01) tendency in all the molecular markers in predicting the malignant from benign lesions. The ultrasound characteristics could significantly (P < 0.001) predict malignant nodules with a significant (P < 0.05) prediction tendency. The scores of Galectin-3, c-Met and CK19 significantly (P < 0.05) increased with increase of ultrasound malignancy risk degree. In malignant and benign lesions differentiated by ultrasound, no significant (P > 0.05) difference existed in HBME-1 expression, however, with ultrasound malignancy risk increase, the score of HBME-1 expression increased significantly (P = 0.03). Galectin-3, c-Met, HBME-1 and CK19 have significantly greater expressions in thyroid malignant than benign lesions and their expression increases with increase of ultrasound malignancy risk. The combination of both ultrasound and molecular markers can be used to differentiate malignant and benign thyroid lesions.

The anteroposterior diameter of nodules in the risk assessment of papillary thyroid microcarcinoma.

This study investigates the application of ultrasound, especially the anteroposterior diameter of nodules in the malignancy and metastasis risk assessment of papillary thyroid microcarcinoma through a retrospective analysis of 500 cases of thyroid nodule ultrasonography.We selected 500 patients with thyroid nodules (maximum nodule diameter ≤2.0 cm) that had been diagnosed clinically and graded TI-RADS 4c by ultrasonography and surgically treated. Among these, there were 258 cases of pathologically diagnosed papillary thyroid microcarcinoma, 72 cases of nodular goiter or adenoma, 137 cases of papillary thyroid carcinoma, 28 cases of acinar cell carcinoma, and 5 cases of undifferentiated carcinoma. In all cases, color Doppler ultrasonography had been performed preoperatively to determine the size and number of nodules, surrounding lymph node metastasis, and TI-RADS grading. Cases of papillary thyroid microcarcinoma diagnosed by pathology were selected as the study group, and cases of nodular goiter or adenoma as the control group. Each group was further subdivided based on the anteroposterior, vertical, and transverse nodule diameters. Intergroup statistical analysis was also performed. Receiver operating characteristic (ROC) curve analysis was conducted on the study and control groups based on the anteroposterior nodule diameters, and the optimal critical value for malignancy risk was determined. Thyroid nodules in the study group were divided into groups based on the presence or absence of lymph node metastasis. Based on the anteroposterior nodule diameter, ROC curve analysis was performed, and the optimal critical value for metastasis risk was determined.There were 500 cases of malignant nodules diagnosed by ultrasound. Among these, there were 428 cases of malignant nodules diagnosed by pathology. The coincidence rate of the ultrasound diagnosis with pathological diagnosis was 85.60%. While, interestingly, There was a significant statistical difference between the study and control groups based on the anteroposterior nodule diameter. When the anteroposterior nodule diameter was 0.7 cm, sensitivity of malignant diagnosis was 76.70% and specificity of that was 66.70%, and the Youden index was the highest. The lymph node metastasis rate for papillary thyroid microcarcinoma was 13.95%. Within this group, the lymph node metastasis rate for nodules ≥0.9 cm (anteroposterior diameter) was 38.46%. When the anteroposterior nodule diameter was equal to 0.9 cm, sensitivity of diagnosis was 83.30%, and specificity of that was 77.80%, and the Youden index was the highest.The anteroposterior diameter of thyroid nodules is more suitable for assessing their malignancy with 0.7 cm, which can be used as the critical value. Nodules ≥ 0.7 cm require surgical treatment, and those <0.7 cm can be observed. An anteroposterior diameter of 0.9 cm can be used as the critical value for assessing the metastasis risk of malignant thyroid nodules. During surgery, the dissection of central cervical lymph nodes is required for nodules ≥0.9 cm.

Individualizing Surgery in Papillary Thyroid Carcinoma Based on a Detailed Sonographic Assessment of Extrathyroidal Extension.

BACKGROUND: Lobectomy may be sufficient for patients with intrathyroidal papillary thyroid carcinomas (PTC) <4 cm without nodal metastasis. Based on the 2015 American Thyroid Association guidelines, a strategy using ultrasound to identify appropriate candidates for lobectomy was implemented. METHODS: Patients with Bethesda V or VI cytology who underwent surgery for PTC (January 2016 to May 2017) were retrospectively reviewed. Eligibility for lobectomy was based on both tumor (unilateral, intrathyroidal tumors ≤3 cm in size) and non-tumor (history of hypothyroidism, radiation exposure, etc.) characteristics. A detailed sonographic assessment of extrathyroidal extension (ETE) included surgeon-performed evaluation of thyroid capsular distortion, a long interface between tumor and thyroid capsule, irregular or indistinct tumor margins abutting the thyroid capsule, or a tracheal footprint. RESULTS: Of 141 patients with PTC, 35 (25%) patients were candidates for lobectomy, and 105 (75%) patients were not candidates for lobectomy because of non-tumor (n = 46) or tumor (n = 59) characteristics. Of the 35 patients who were candidates for lobectomy, 27 had sonographic ETE on detailed assessment. Total thyroidectomy was performed in 23 patients, while thyroid lobectomy was performed in 12 patients. Total thyroidectomy was indicated based on final histopathology in 15 patients (ETE, aggressive histology, vascular invasion, or cervical metastasis). Histopathologic ETE was present in 13 of these 15 patients and was the only indication for total thyroidectomy in the remaining eight patients. Positive and negative predictive values for the prediction of ETE based on detailed sonographic assessment were 52% and 100%, respectively. In comparison to a strategy of routine total thyroidectomy, a detailed sonographic assessment of ETE reduced the rate of potentially avoidable total thyroidectomy from 57% to 31%. CONCLUSIONS: Patients with PTC who are potential candidates for lobectomy often require total thyroidectomy based on microscopic ETE detected on surgical pathology. A detailed sonographic assessment of ETE can reliably rule out microscopic ETE, reducing the rate of potentially avoidable total thyroidectomy.

Validation of American Thyroid Association Ultrasound Risk Assessment of Thyroid Nodules Selected for Ultrasound Fine-Needle Aspiration.

OBJECTIVE: The aim of this study was to validate the American Thyroid Association (ATA) sonographic risk assessment of thyroid nodules. METHODS: The ATA sonographic risk assessment was prospectively applied to 206 thyroid nodules selected for ultrasound-guided fine-needle aspiration (US-FNA), and analyzed with The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC), as well as surgical pathology for the subset undergoing surgical excision. RESULTS: The analysis included 206 thyroid nodules averaging 2.4 cm (range 1-7 cm; standard error of the mean 0.07). Using the ATA US pattern risk assessment, nodules were classified as high (4%), intermediate (31%), low (38%), and very low (26%) risk of malignancy. Nodule size was inversely correlated with sonographic risk assessment, as lower risk nodules were larger on average (p < 0.0001). Malignancy rates determined by cytology/surgical pathology were high 100%, intermediate 11%, low 8%, and very low 2%, which were closely aligned with ATA malignancy risk estimates (high 70-90%, intermediate 10-20%, low 5-10%, and very low 3%). ATA US pattern risk assessment also appropriately predicted the proportion of nodules classified as malignant or suspicious for malignancy through TBSRTC classification-high (77%), intermediate (6%), low (1%), and very low 0%-as well as benign TBSRTC classification-high (0%), intermediate (47%), low (61%), and very low (70%) (p < 0.0001). Malignancy rates of surgically excised, cytologically indeterminate nodules followed ATA sonographic risk stratification (high 100%, intermediate 21%, low 17%, and very low 12%; p = 0.003). CONCLUSION: This prospective study supports the new ATA sonographic pattern risk assessment for selection of thyroid nodules for US-FNA based upon TBSRTC and surgical pathology results. In the setting of indeterminate cytopathology, nodules categorized as atypia of undetermined significance/follicular lesion of undetermined significance with ATA high-risk sonographic patterns have a high likelihood of being malignant.

Ultrasonographic Assessment of Differential Diagnosis Between Degenerating Cystic Thyroid Nodules and Papillary Thyroid Microcarcinomas.

PURPOSE: To enhance the diagnostic accuracy of conventional ultrasonography in differentiating papillary thyroid microcarcinomas (PTMCs) from degenerating cystic thyroid nodules mimicking malignancy (under 10 mm in diameter). METHODS: A retrospective analysis of hypoechoic thyroid nodules under 10 mm between 162 cases of degenerating cystic thyroid nodules confirmed by ultrasound-guided fine-needle aspiration (US-FNA) and 150 cases of PTMCs confirmed by both US-FNA and postoperative pathology were performed in the aspects of shape, margin, calcification, and vascularity. RESULTS: Significant differences were observed in the aspects of shape, rim calcification, and vascularity (P < 0.05) between two groups in condition of solid hypoechogenicity. An ovoid-to-round regular shape, rim calcification, and no intrinsic blood flow were the statistically significant features for the depiction of a benign degenerating cystic nodule, while a taller-than-wide shape and peripheral or intranodular blood flow were that of a malignancy. Multiple stepwise logistic regression analysis demonstrated each of them as an independent predictor of malignancy (P < 0.05). CONCLUSIONS: Shape, rim calcification, and vascularity are efficient criteria to distinguish degenerating cystic thyroid nodules mimicking malignancy from PTMCs in cases of solid hypoechogenic nodules under 10 mm. Such criteria should be acknowledged in cases of solid hypoechogenic thyroid nodules to help guide for the need of US-FNA.

[Assessment and surgical treatment for 58 substernal goiter].

Objective: To investigate the diagnosis and treatment of substernal goiter. Methods: A total of 58 cases with substernal goiters undergoing surgery between January 2005 and December 2015 were analysed retrospectively. There were 10 males and 48 females and their age ranged from 38 to 82 years with a median age of 58 years. According to enhanced CT and clinical signs of substernal goiters, there were 40 cases for typeⅠ, 17 cases for type Ⅱ, and 1 case for type Ⅲ. Results: Patients with typeⅠand Ⅱ substernal goiters (8 cases of papillary carcinoma) underwent low neck and collar-type incision, and patients with type Ⅲ substernal goiters received carotid chest surgery. The use of harmonic scalpel in sternal goiter surgery provided with clearer surgical field, less bleeding. All the operations were successful, and recurrent laryngeal nerve was visually identified in all patients. Postoperative complications included trachyphonia (2 cases), without difficult breathing and tracheal stenosis. Conclusions: Enhanced CT is the best means of preoperatively assessment of substernal goiter. It is feasible to treat patients with typeⅠand Ⅱ substernal goiters by lower neck and collar-type incision. Use of harmonic scalpel in substernal goiter surgery can reduce operation time and bleeding.

A Computer-Aided Diagnosis System Using Artificial Intelligence for the Diagnosis and Characterization of Thyroid Nodules on Ultrasound: Initial Clinical Assessment.

BACKGROUND: An initial clinical assessment is described of a new, commercially available, computer-aided diagnosis (CAD) system using artificial intelligence (AI) for thyroid ultrasound, and its performance is evaluated in the diagnosis of malignant thyroid nodules and categorization of nodule characteristics. METHODS: Patients with thyroid nodules with decisive diagnosis, whether benign or malignant, were consecutively enrolled from November 2015 to February 2016. An experienced radiologist reviewed the ultrasound image characteristics of the thyroid nodules, while another radiologist assessed the same thyroid nodules using the CAD system, providing ultrasound characteristics and a diagnosis of whether nodules were benign or malignant. The diagnostic performance and agreement of US characteristics between the experienced radiologist and the CAD system were compared. RESULTS: In total, 102 thyroid nodules from 89 patients were included; 59 (57.8%) were benign and 43 (42.2%) were malignant. The CAD system showed a similar sensitivity as the experienced radiologist (90.7% vs. 88.4%, p > 0.99), but a lower specificity and a lower area under the receiver operating characteristic (AUROC) curve (specificity: 74.6% vs. 94.9%, p = 0.002; AUROC: 0.83 vs. 0.92, p = 0.021). Classifications of the ultrasound characteristics (composition, orientation, echogenicity, and spongiform) between radiologist and CAD system were in substantial agreement (κ = 0.659, 0.740, 0.733, and 0.658, respectively), while the margin showed a fair agreement (κ = 0.239). CONCLUSION: The sensitivity of the CAD system using AI for malignant thyroid nodules was as good as that of the experienced radiologist, while specificity and accuracy were lower than those of the experienced radiologist. The CAD system showed an acceptable agreement with the experienced radiologist for characterization of thyroid nodules.

Assessment of a Revised Management Strategy for Patients With Intraductal Papillary Mucinous Neoplasms Involving the Main Pancreatic Duct.

Importance: According to the 2012 International Consensus Guidelines, the diagnostic criterion of intraductal papillary mucinous neoplasms (IPMNs) involving the main duct (MD IPMNs) or the main and branch ducts (mixed IPMNs) of the pancreatic system is a main pancreatic duct (MPD) diameter of 5.0 mm or greater on computed tomography (CT) or magnetic resonance imaging (MRI). However, surgical resection is recommended for patients with an MPD diameter of 10.0 mm or greater, which is characterized as a high-risk stigma. An MPD diameter of 5.0 to 9.0 mm is not an indication for immediate resection. Objectives: To determine an appropriate cutoff (ie, one with high sensitivity and negative predictive value) of the MPD diameter on CT or MRI as a prognostic factor for malignant disease and to propose a new management algorithm for patients with MD or mixed IPMNs. Design, Setting, and Participants: This retrospective cohort study included 103 patients who underwent surgical resection for a preoperative diagnosis of MD or mixed IPMN and in whom IPMN was confirmed by surgical pathologic findings at a single institution from July 1, 1996, to December 31, 2015. Main Outcomes and Measures: Malignant disease was defined as high-grade dysplasia or invasive adenocarcinoma on results of surgical pathologic evaluation. An appropriate MPD diameter on preoperative CT or MRI to predict malignant disease was determined using a receiver operating characteristic curve analysis. The prognostic value of the new management algorithm that incorporated the new MPD diameter cutoff was evaluated. Results: Among the 103 patients undergoing resection for an MD or mixed IPMN (59 men [57.3%]; 44 women [42.7%]; median [range] age, 71 [48-86] years), 64 (62.1%) had malignant disease. Diagnostic accuracy for malignant neoplasms was highest at an MPD diameter cutoff of 7.2 mm (area under the receiver operating characteristic curve, 0.70; 95% CI, 0.59-0.81). An MPD diameter of 7.2 mm or greater was also an independent prognostic factor for malignant neoplasms (odds ratio, 12.76; 95% CI, 2.43-66.88; P = .003) on logistic regression analysis after controlling for preoperative variables. The new management algorithm, which included an MPD diameter of 7.2 mm or greater as one of the high-risk stigmata, had a higher sensitivity (100%), negative predictive value (100%), and accuracy (66%) for malignant disease than the 2012 version of the International Consensus Guidelines (95%, 57%, and 63%, respectively). Conclusions and Relevance: In this single-center, retrospective analysis, an MPD diameter of 7.2 mm was identified as an optimal cutoff for a prognostic factor for malignant disease in MD or mixed IPMN. These data support lowering the accepted criteria for MPD diameter when selecting patients for resection vs surveillance so as not to overlook cancer in IPMN.

Assessment of Malignant Potential in Intraductal Papillary Mucinous Neoplasms of the Pancreas: Comparison between Multidetector CT and MR Imaging with MR Cholangiopancreatography.

PURPOSE: To compare the diagnostic performance of multidetector computed tomography (CT) and magnetic resonance (MR) imaging with MR cholangiopancreatography (MRCP) in identifying the malignant potential of pancreatic intraductal papillary neoplasms (IPMNs) and evaluate their intermodality agreement. MATERIALS AND METHODS: Institutional review board approval was obtained, and the requirement for informed consent was waived for this retrospective study. In 129 patients with pathologically proved pancreatic IPMNs, three reviewers independently evaluated their preoperative CT and MR imaging with MRCP findings. Intermodality agreement between multidetector CT and MR imaging with MRCP, as well as interobserver agreement of each imaging modality, for depicting high-risk stigmata and worrisome features were assessed. Diagnostic values of other signs of overt malignancy, including the presence of a parenchymal mass and local-regional extension, were analyzed. Diagnostic performance and intermodality agreement were assessed by using receiver operating characteristics (ROC) curve analysis and weighted κ statistics. RESULTS: Overall, multidetector CT and MR imaging with MRCP were similar in their ability to depict signs suspicious or indicative of malignancy in patients with IPMN (area under the ROC curve [AUC] = 0.82 for both), with good intermodality agreement (κ = 0.75) and moderate interobserver agreement (κ = 0.47-0.59) when high-grade dysplasia was used as the cutoff for malignancy. When parenchymal masses and local-regional extensions were also considered as overt signs of malignancy, the ability to identify invasive IPMNs significantly increased (AUC = 0.87 for CT and AUC = 0.88 for MR imaging), with high sensitivity (94.3%), while maintaining specificity (69.1%). CONCLUSION: The diagnostic performance of multidetector CT and MR imaging with MRCP for identifying the malignant potential of pancreatic IPMNs was similar and showed good intermodality agreement, suggesting that follow-up with either modality may be used.

Assessment of recurrence rates in papillary thyroid microcarcinoma patients with and without histopathological risk factors after radioiodine ablation treatment.

AIM: We aimed to assess the recurrence rates of papillary thyroid microcarcinoma in patients with and without histopathological risk factors after radioiodine (RAI) ablation treatment. MATERIALS AND METHODS: A total of 357 papillary thyroid microcarcinoma patients who were referred to Ankara University Medical School, Department of Nuclear Medicine for RAI ablation treatment after total or near-total thyroidectomy were included in the study. All patients received RAI ablation treatment 4-6 weeks after surgery. After RAI ablation, patients were monitored every 3 months within the first 6 months and then every year. RESULTS: During follow-up, sixth-month iodine-131 (I-131) whole-body scans showed successful ablation in 333 (93.3%) patients. However, one (0.2%) patient had a focal lung uptake on the sixth-month I-131 whole-body scan, although the postablative scan gave no evidence of lung metastasis. Lung metastasis of this patient was treated with a second dose of RAI. The mean follow-up period was 124 (min-max: 6-216) months. No recurrence was detected in 344 (96.3%) patients during the follow-up period. However, in 13 (3.6%) patients, new recurrence or metastasis had developed. Lymph node metastasis was detected using fluorine-18 flourodeoxyglucose PET/computed tomography in four and using neck ultrasound in eight of them. The metastasis rates of patients with papillary microcarcinoma at a single focus with no thyroid capsule or lymphovascular invasion (n=268) and those of patients with thyroid capsule and/or lymphovascular invasion (n=89) were compared. Metastasis was seen in six and seven patients in those groups, respectively. The difference in metastasis rate between the two groups was statistically significant (2.2 vs. 9.2%, P=0.008). CONCLUSION: RAI ablation is beneficial in the management of papillary thyroid microcarcinoma patients with histopathological risk factors. It also improves the sensitivity of thyroglobulin and antithyroglobulin, facilitating easier and safer follow-up.

Quantitative assessment of in vivo breast masses using ultrasound attenuation and backscatter.

Clinical analysis of breast ultrasound imaging is done qualitatively, facilitated with the ultrasound breast imaging-reporting and data system (US BI-RADS) lexicon, which helps to standardize imaging assessments. Two descriptors in that lexicon, "posterior acoustic features" and the "echo pattern" within a mass, are directly related to quantitative ultrasound (QUS) parameters, namely, ultrasound attenuation and the average backscatter coefficient (BSC). The purpose of this study was to quantify ultrasound attenuation and backscatter in breast masses and to investigate these QUS properties as potential differential diagnostic markers. Radio frequency (RF) echo signals were from patients with breast masses during a special ultrasound imaging session prior to core biopsy. Data were also obtained from a well characterized phantom using identical system settings. Masses include 14 fibroadenomas and 10 carcinomas. Attenuation for the acoustic path lying proximal to the tumor was estimated offline using a least squares method with constraints. BSCs were estimated using a reference phantom method (RPM). The attenuation coefficient within each mass was assessed using both the RPM and a hybrid method, and effective scatterer diameters (ESDs) were estimated using a Gaussian form factor model. Attenuation estimates obtained with the RPM were consistent with estimates done using the hybrid method in all cases except for two masses. The mean slope of the attenuation coefficient versus frequency for carcinomas was 20% greater than the mean slope value for the fibroadenomas. The product of the attenuation coefficient and anteroposterior dimension of the mass was computed to estimate the total attenuation for each mass. That value correlated well with the BI-RADS assessment of "posterior acoustic features" judged qualitatively from gray scale images. Nearly all masses were described as "hypoechoic," so no strong statements could be made about the correlation of echo pattern findings in BI-RADS with the averaged BSC values. However, most carcinomas exhibited lower values for the frequency-average BSC than fibroadenomas. The mean ESD alone did not differentiate the mass type, but fibroadenomas had greater variability in ESDs within the ROI than that found for invasive ductal carcinomas. This study demonstrates the potential to use attenuation and QUS parameters associated with the BSC as quantitative descriptors.