Ha Yan Kim

A nomogram for predicting underestimation of invasiveness in ductal carcinoma in situ diagnosed by preoperative needle biopsy

It is unnecessary to perform axillary staging in patients with ductal carcinoma in situ (DCIS) of the breast because of the low incidence of axillary metastasis. However, diagnosis of DCIS by core needle biopsy showed a high rate of underestimation of invasive cancer. Thus, it is necessary to predict invasiveness in DCIS patients on core before surgery. We analyzed 340 patients with DCIS diagnosed by needle biopsy. The cases were divided into training and validation sets. Logistic regression was performed to predict the presence of invasive cancer in the final pathology, and a nomogram was constructed from the training set using the presence of palpability, the presence of ultrasonographic calcification and mass, the biopsy tools, and the presence of microinvasion. The model was subsequently applied to the validation set. The nomogram for the training set was both accurate and discriminating, with an area under the receiver operating characteristic curve (AUC) of 0.75. When applied to the validation group, the model accurately predicted the likelihood of invasive cancer (AUC: 0.71). Our nomogram will allow surgeons to easily and accurately estimate the likelihood of invasive cancer in patients with DCIS as diagnosed by preoperative needle biopsy.

Intrahepatic mass-forming cholangiocarcinoma: prognostic value of preoperative gadoxetic acid-enhanced MRI

AbstractObjectivesTo assess whether gadoxetic acid-enhanced MRI could be used as a prognostic factor for intrahepatic mass-forming cholangiocarcinomas (IMCCs).MethodsForty-one patients with pathologically proven IMCCs who underwent preoperative gadoxetic acid-enhanced MRI were included. The signal intensity of the IMCCs on hepatobiliary phase (HBP) MRI was qualitatively analyzed by two radiologists, and categorized into intermediate or hypointense groups. Analysis of clinicopathological prognostic factors and correlations of imaging and histology were also performed. Survival time and time to recurrence (TTR) were analyzed.ResultsOf the 41 IMCCs, 23 were in the intermediate group and 18 were in the hypointense group on HBP MRI. IMCCs in the intermediate group were associated with shorter survival time (P = 0.048) and TTR (P = 0.002) than the IMCCs of the hypointense group. Only the intermediate group on HBP MRI had a significantly shorter TTR on multivariate analysis (P = 0.012). The IMCCs of the intermediate group showed a tendency for more abundant tumour fibrous stroma than those of the hypointense group (P = 0.027).ConclusionsThe enhancement of IMCCs on HBP gadoxetic acid-enhanced MRI appears to correlate with tumour aggressiveness and outcomes due to the tumour fibrous stromal component. Thus, HBP images could be a useful prognostic factor for IMCCs after surgery.Key points• The enhancement of IMCCs on HBP correlates with the tumour fibrous stroma. • The enhancement of IMCCs on HBP MRI appears to correlate with prognosis. • Gadoxetic acid-enhanced MRI is helpful for predicting prognosis of IMCCs after surgery.

Variability in Interpretation of Ultrasound Elastography and Gray-Scale Ultrasound in Assessing Thyroid Nodules

The aim of this study was to validate inter-observer variability for strain ultrasound elastography (USE) and to compare the diagnostic performance of a combination of gray-scale ultrasound (US) and USE with that of gray-scale US. Three observers from different institutions evaluated gray-scale US images and USE video files of 443 cytopathologically proven benign or malignant thyroid nodules over a 3-mo period. Inter-observer variability did not statistically differ between USE using the Asteria criteria and gray-scale US; however, USE using the Rago criteria had the lowest inter-observer agreement (p < 0.043). For all three observers, sensitivity was increased by adding USE to gray-scale US (81.3%-88.3%, 75.4%-85.4%) compared with gray-scale US (70.4%-80.8%). Specificity was decreased by adding USE to gray-scale US (51.7%-59.1%, 59.1%-73.9%) compared with gray-scale US (69.0%-82.8%). USE and gray-scale US had comparable inter-observer variability. However, on addition of USE to gray-scale US, the additional diagnostic yield was limited compared with that of gray-scale US alone.

Application of Thyroid Imaging Reporting and Data System in the Ultrasound Assessment of Thyroid Nodules According to Physician Experience.

Objective The aim of this study was to investigate and compare the diagnostic performances of the Thyroid Imaging Reporting and Data System (TIRADS) in differentiating benign and malignant thyroid nodules according to the level of physician experience. Materials and Methods From March to October 2013, 1102 patients with 1128 thyroid nodules who underwent initial ultrasound-guided fine needle aspiration were included in this study. Thyroid nodules were categorized according to TIRADS. Diagnostic performances of ultrasound were compared according to performer experience using the &khgr;2 test or Fisher exact test. Results Of 1128 thyroid nodules, 281 were malignant, and 847 were benign. The risk of malignancy of each TIRADS category by the experienced and less experienced physicians were as follows: category 3 (0.9% vs 0%), category 4a (3.5% vs 1.3%), category 4b (7.3% vs 12.1%), category 4c (67.5% vs 44.9%), and category 5 (97.7% vs 76.5%). Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 99.1%, 35.9%, 52.5%, 35.5%, and 99.1%, respectively, for experienced physicians and 100%, 20.9%, 37.6%, 35.2%, and 100%, respectively, for less experienced physicians. Specificity, accuracy, and positive predictive value were statistically higher for experienced physicians than those for less experienced physicians (P < 0.001, 0.001, and 0.004). There was a significant difference in areas under the curve between the 2 groups (P < 0.001). Conclusions In conclusion, the diagnostic performance of the stratification of malignancy risk according to TIRADS categories was comparable between the experienced and less experienced physician groups. The application of TIRADS is reproducible, and it was easy to predict the probability of thyroid malignancy in both the experienced and less experienced physician groups.

Optimal Acquisition Number for Hepatic Shear Wave Velocity Measurements in Children.

Objective To investigate the minimum optimal acquisition number of hepatic shear wave velocities (SWVs) on ultrasound elastography in children. Materials and Methods We prospectively performed hepatic supersonic shear wave elastography in children of four groups (group A-C, healthy children, group A with 0–5 years old; group B with 6–10 years old; group C with 11–18 years old; and group D, children with previous Kasai operation) with free breathing (FB) and breath holding (BH) status, if possible. SWVs were measured fifteen times for each child at a 4 cm depth for the right lobe using a 1–6 MHz convex transducer. Mean SWVs from three, five, and seven acquisitions were compared to the mean SWV from fifteen measurements, using an intraclass correlation coefficient (ICC) analyzed with the 1,000 times bootstrap method. Results Total eighty-eight children were included (25 children in group A, 30 children in group B, 21 children in group C, and 12 children in group D). The mean SWVs from fifteen measurements in FB status were 5.5 ± 1.3 kPa for groups A-C together and 8.0 ± 2.2 kPa for group D. For all groups together, mean SWVs from the three (ICC 0.944 and 0.937), five (ICC 0.958 and 0.938) and seven (ICC 0.969 and 0.941) acquisitions demonstrated almost perfect agreement with the reference of fifteen acquisitions in both FB and BH status, respectively. A subgroup analysis showed three measurements were in almost perfect agreement during FB for groups B-D and strong agreement (ICC 0.675) for group A. Conclusion Three acquisitions can be enough for hepatic SWVs in children more than 6 years old regardless of breathing status or hepatic pathology. More acquisitions are recommended for children under the age of 5 years during FB.

Rectal Mucinous Adenocarcinoma: MR Imaging Assessment of Response to Concurrent Chemotherapy and Radiation Therapy—A Hypothesis-generating Study

Purpose To develop a system for assessment of tumor regression grade (TRG) with magnetic resonance (MR) imaging that is applicable to rectal mucinous adenocarcinoma (RMAC) and to obtain a preliminary evaluation of the association of MR imaging assessment of TRG with response to preoperative concurrent chemotherapy and radiation therapy (CCRT). Materials and Methods This retrospective study was approved by the institutional review board, and informed consent was waived. Pre- and post-CCRT MR images of 59 patients with RMAC (median age, 59 years; range, 29-80 years; 42 men [median age, 59 years; range, 36-80 years] and 17 women [median age, 57 years; range, 29-79 years]) who underwent CCRT and subsequent elective resection from July 2005 to June 2015 were analyzed. Two experienced gastrointestinal radiologists independently analyzed imaging parameters such as T stage, mesorectal fascia status, extramural vascular invasion status, and TRG by using modified criteria developed for assessment of RMAC. Interobserver variability was calculated with weighted κ analysis, and disagreement was settled in consensus. MR imaging TRG results were compared with those from pathologic TRG analysis (Mandard grade). Logistic regression analyses were performed to evaluate associations between imaging parameters and pathologic TRG. Results There was moderate to substantial agreement for imaging parameters (post-CCRT T stage-weighted κ, 0.7134; post-CCRT mesorectal fascia status, 0.618; TRG, 0.5023). Modified MR imaging TRG results were significantly associated with pathologic responsiveness (responsive group, Mandard grade 1 or 2; nonresponsive group, Mandard grades 3-5; P = .023). Results of univariate and multivariate logistic regression analyses indicated that MR imaging TRG was the only factor significantly associated with CCRT responsiveness (univariate analysis, P = .023; multivariate analysis, P = .0261). Conclusion The modified MR imaging assessment of TRG was associated with treatment response to CCRT in patients with RMAC.

Combined use of CEMIP and CA 19-9 enhances diagnostic accuracy for pancreatic cancer

Carbohydrate antigen (CA) 19-9 is the only diagnostic marker used in pancreatic cancer despite its limitations. Here, we aimed to identify the diagnostic role of CEMIP (also called KIAA1199) combined with CA 19-9 in patients with pancreatic cancer. A retrospective analysis of prospectively collected patient samples was performed to determine the benefit of diagnostic markers in the diagnosis of pancreatic cancer. We investigated CEMIP and CA 19-9 levels in 324 patients with pancreatic cancer and 49 normal controls using serum enzyme-linked immunosorbent assay. Median CA 19-9 and CEMIP levels were 410.5 U/ml (40.8–3342.5) and 0.67 ng/ml (0.40–1.08), respectively, in patients with pancreatic cancer. The AUROC for CA 19-9 and CEMIP were 0.847 (95% confidence interval [CI]: 0.806–0.888) and 0.760 (95% CI: 0.689–0.831), respectively. Combination of CA 19-9 with CEMIP showed markedly improved AUROC over CA 19-9 alone in pancreatic cancer diagnosis (0.94 vs. 0.89; P < 0.0001). CEMIP showed a diagnostic yield of 86.1% (68/79) in CA 19-9 negative pancreatic cancer. Combined use with CEMIP showed significantly improved diagnostic value compared with CA 19-9 alone in pancreatic cancer. Especially, CEMIP may be a complementary marker in pancreatic cancer patients with normal CA 19-9 levels.

Serum anion gap at admission as a predictor of mortality in the pediatric intensive care unit

An accurate method to predict the mortality in the intensive care unit (ICU) patients has been required, especially in children. The aim of this study is to evaluate the value of serum anion gap (AG) for predicting mortality in pediatric ICU (PICU). We reviewed a data of 461 pediatric patients were collected on PICU admission. Corrected anion gap (cAG), the AG compensated for abnormal albumin levels, was significantly lower in survivors compared with nonsurvivors (p < 0.001). Multivariable logistic regression analysis identified the following variables as independent predictors of mortality; cAG (OR 1.110, 95% CI 1.06–1.17; p < 0.001), PIM3 [OR 7.583, 95% CI 1.81–31.78; p = 0.006], and PRISM III [OR 1.076, 95% CI 1.02–1.14; p = 0.008]. Comparing AUCs for mortality prediction, there were no statistically significant differences between cAG and other mortality prediction models; cAG 0.728, PIM2 0.779, PIM3 0.822, and PRISM III 0.808. The corporation of cAG to pre-existing mortality prediction models was significantly more accurate at predicting mortality than using any of these models alone. We concluded that cAG at ICU admission may be used to predict mortality in children, regardless of underlying etiology. And the incorporation of cAG to pre-existing mortality prediction models might improve predictability.

Original scientific articleLearning Curve for Single-Incision Laparoscopic Anterior Resection for Sigmoid Colon Cancer

BACKGROUND Compared with conventional laparoscopic surgery, single-incision laparoscopic surgery produces better cosmetic benefits. The aim of this study was to investigate the learning curve for single-incision laparoscopic anterior resection (SILAR) for sigmoid colon cancer using multidimensional methods. STUDY DESIGN From September 2009 through May 2014, one hundred and thirteen patients underwent SILAR for sigmoid colon cancer by a single surgeon at Severance Hospital. The learning curve was analyzed using moving average, cumulative sum control chart (CUSUM), and risk-adjusted CUSUM methods. For risk-adjusted CUSUM, surgical failure was defined as conversion to open surgery or conventional laparoscopic surgery, morbidity within 30 days after surgery, <12 harvested lymph nodes, or local recurrence. RESULTS Using the moving average method, the peak point for operation time occurred at the 65(th) case (173 minutes). The CUSUM method also showed the operation time peak point at the 65(th) case. However, the risk-adjusted CUSUM curve did not ascend after the 61st case. The operation time and hospital stay for the 60 phase 1 patients (cases 1 to 60) were longer than for 53 phase 2 patients (cases 61 to 113) (166.6 vs 140 minutes; p < 0.001 and 7.1 vs 5.5 days; p = 0.009). Phase 2 patients had a significantly larger tumor diameter and more harvested lymph nodes. CONCLUSIONS The learning curve for SILAR for sigmoid colon cancer was 61 to 65 cases according to multidimensional statistical analyses. Single-incision laparoscopic anterior resection is feasible for surgeons experienced in laparoscopic surgery. However, SILAR required more cases for proficiency than the number previously reported for conventional laparoscopic surgery, likely because of its technical challenges.