Eun Young Ko

Inoperable Symptomatic Recurrent Thyroid Cancers: Preliminary Result of Radiofrequency Ablation

PurposeTo determine the role of radiofrequency ablation (RFA) in patients with inoperable symptomatic recurrent thyroid cancers.Materials and MethodsEleven patients with 16 symptomatic recurrent thyroid cancers but ineligible for surgery were prospectively enrolled and underwent ultrasound-guided RFA with local anesthesia in 16 sessions. The mean tumor volume and diameter were 9xa0ml (range 0.1–34xa0ml) and 2.9xa0cm (range 0.7–4.8xa0cm), respectively. Patients had dysphagia, hoarseness, dyspnea, or a protruding mass due to recurrent tumors. Tumor volume was calculated from follow-up ultrasound, and symptoms were assessed after RFA.ResultsOf 16 sessions, tumor ablation was complete in 6, incomplete in 9, and failed in 1. Incomplete or failed ablation was due to intolerable pain, severe calcified lesion, or tumor encasement of major vessels. Of 15 treated lesions, 13 decreased in volume. Regrowth of treated tumors was observed in 2 lesions. The mean volume reduction was 50.9% (range −9.4 to 96.8%). There were gains for symptom relief for 7 patients (63.6%) with protruding masses (nxa0=xa06) and discomfort due to tracheal compression (nxa0=xa01). The mean follow-up was 6xa0months (1–14xa0months). There were no major complications except a patient with skin burn.ConclusionRFA is feasible and safe, and can improve symptoms in the short term.

Analysis of factors that influence the accuracy of magnetic resonance imaging for predicting response after neoadjuvant chemotherapy in locally advanced breast cancer

PurposeThe purpose of this study was to evaluate the accuracy of breast magnetic resonance imaging (MRI) to predict residual lesion size after neoadjuvant chemotherapy (NAC) and to determine the factors that influence the accuracy of response prediction.MethodsThis study comprised 166 patients who underwent MRI before and after NAC, but before surgery. The longest diameter of the residual cancer was measured using MRI and correlated with pathologic findings. Patients were further divided into subgroups according to various radiologic and histopathologic factors. Pathologic complete response (pCR) was defined as the absence of residual invasive cancer cells. The Pearson correlation was used to correlate tumor size as determined by MRI and pathology, and the Mann-Whitney U test and Kruskal-Wallis test were used to compare MRI-pathologic size discrepancies according to various clinical, histopathologic factors, and MRI findings.ResultsOf the 166 women, 40 achieved pCR. The overall sensitivity, specificity, and accuracy for diagnosing invasive residual disease by using MRI were 96, 65, and 89xa0%, respectively. The Pearson’s correlation coefficient between the tumor sizes measured using MRI and pathology was 0.749 (Pxa0<xa00.001). The size discrepancy was significantly greater in patients with estrogen receptor-positive cancer (Pxa0=xa00.037), in cancers with low nuclear grade (Pxa0=xa00.007), and in cancers shown as diffuse non-mass–like enhancement on MRI (Pxa0=xa00.001).ConclusionsSize prediction is less accurate in cases with estrogen receptor-positive breast cancer, low nuclear grade, and diffuse non-mass–like enhancement on initial MRI.

Thyroid Lymphoma Correlation of Radiologic and Pathologic Features

The purpose of this study was to correlate the clinicoradiologic and pathologic features of thyroid lymphoma and to identify the most useful diagnostic method for thyroid lymphoma as the first line.

Does pre-operative breast magnetic resonance imaging in addition to mammography and breast ultrasonography change the operative management of breast carcinoma?

Magnetic resonance imaging (MRI) has been used for the local staging of breast cancer, especially to determine the extent of multiple lesions and to identify occult malignancies. The aim of this study was to evaluate the effect of pre-operative MRI on the surgical treatment of breast cancer. Between January 2006 and May 2007, 535 newly diagnosed breast cancer patients who planned to undergo breast conserving surgery had clinical examinations, bilateral mammography, breast ultrasonography, and breast MRI. The radiologic findings and clinicopathologic data were reviewed retrospectively. Ninety-eight (18.3%) patients had additional lesions, shown as suspicious lesions on breast MRI, but not detected with conventional methods. Eighty-four (15.7%) of these patients had a change in surgical treatment plans based on the MRI results. Forty-seven (8.8%) of the 84 patients had additional malignancies; the other 37 patients (6.9%) had benign lesions. The positive predictive value for MRI-based surgery was 56.0% (47 of 84 patients). During the period of study, the use of pre-operative MRI was increased with time (OR 1.20; 95% CI 1.16–1.23; Pxa0<xa00.001), but the mastectomy rate did not change significantly (OR 0.98; 95% CI 0.95–1.00; Pxa0=xa00.059). Multiple factors were analyzed to identify the patients more likely to undergo appropriate and complete surgery based on the additional findings of the pre-operative MRI, but the results were not statistically significant. This research suggests that a pre-operative MRI can potentially lower the rate of incompletely excised malignancies by identifying additional occult cancer prior to surgery and does not lead to an increase in the mastectomy rate; however, because some benign lesions are indistinguishable from suspicious or malignant lesions, excessive surgical procedures are unnecessarily performed in a significant portion of patients. In the future, the criteria for the use of MRI in local staging of breast cancer should be established.

Preoperative Ultrasound-Guided Tattooing Localization of Recurrences After Thyroidectomy: Safety and Effectiveness

BackgroundThe incidence of nonpalpable recurrence detected on follow-up ultrasound (US) after thyroidectomy has increased. However, surgical approach for nonpalpable lesions can be difficult. We assessed the safety and effectiveness of ultrasound-guided tattooing (US-tattoo) with a charcoal suspension for localizing nonpalpable cervical recurrences after thyroidectomy for thyroid cancer.MethodsBetween March 2004 and February 2008, we retrospectively assessed 55 consecutive patients with 83 lesions who underwent US-tattoo with injection of a charcoal suspension for nonpalpable lesions. All patients underwent the surgical dissection after US-tattoo. The complications and effectiveness of US-tattoo were evaluated using ultrasonographic, surgical, and pathologic records.ResultsAmong 83 lesions, 72 recurrences and 11 benign lesions were confirmed by final pathology. The average size of the localized lesions was 0.7xa0cm (range 0.4–1.4xa0cm). The most common site of tattooing was cervical lymph nodes at level IV. The technical success rate of US-tattoo for suspicious lesions was 96% (80/83). Failure of US-tattoo occurred in lesions located posterior to major vessels. During surgery, all but two successful tattooed lesions were detected by surgeons. No residual lesion was detected at follow-up US. With regard to complications, two patients (4%) had a dot-like marking at the skin puncture site after US-tattoo.ConclusionPreoperative US-tattoo is a safe and effective method for successful reoperation of nonpalpable recurrences after thyroidectomy.

Apparent Diffusion Coefficient in Estrogen Receptor–Positive Invasive Ductal Breast Carcinoma: Correlations with Tumor-Stroma Ratio

PURPOSEnTo determine whether apparent diffusion coefficient (ADC) values vary according to tumor-stroma ratio, dominant stroma type, or presence of central fibrosis in estrogen receptor-positive breast cancer.nnnMATERIALS AND METHODSnInstitutional review board approval was obtained, and patient consent was waived. Sixty-one patients with estrogen receptor-positive invasive ductal carcinoma-not otherwise specified who underwent breast magnetic resonance (MR) imaging with diffusion-weighted (DW) imaging were included in this study. The ADC values of the lesions were measured. Two pathologists evaluated the tumor-stroma ratio, dominant stroma type (collagen, fibroblast, lymphocyte), and central fibrosis. Detectability on DW images was compared between the two groups according to the tumor-stroma ratio (stroma rich or stroma poor). Mean ADC values were retrospectively compared with the tumor-stroma ratio, dominant stroma type, and presence of a central fibrosis. Multiple linear regression analysis was performed to determine variables independently associated with ADC.nnnRESULTSnOn DW images, detectability was not significantly different between stroma-rich and stroma-poor groups (P = .244). ADC values were significantly lower in the stroma-poor group (P < .001). The mean ADC values in the collagen-dominant type were lower than in fibroblast-dominant or lymphocyte-dominant types (P = .021). In multiple linear regression analysis, tumor-stroma ratio (P = .007), tumor size (P = .007), and dominant stroma type (collagen dominant, P = .029) were independently correlated with ADC.nnnCONCLUSIONnIn estrogen receptor-positive breast cancers, ADC values showed significant differences according to the tumor-stroma ratio and dominant stroma type.

Factors Affecting the Efficacy of Ultrasound-Guided Vacuum-Assisted Percutaneous Excision for Removal of Benign Breast Lesions

This study was designed to evaluate the effectiveness of complete removal and factors affecting the presence of a residual mass and complications after ultrasound‐guided vacuum‐assisted percutaneous removal of benign breast lesions.

Additional diagnostic value of shear-wave elastography and color Doppler US for evaluation of breast non-mass lesions detected at B-mode US

AbstractObjectiveTo evaluate the diagnostic value of shear-wave elastography (SWE) and colour Doppler ultrasound (US) for evaluation of breast non-mass lesions (NMLs) detected by B-mode US.MethodsThis retrospective study enrolled 116 NMLs (42 benign, 74 malignant). For each lesion, B-mode US, SWE and colour Doppler US were performed. Mean elasticity (Emean), maximum elasticity (Emax) and vascularity were assessed by SWE and Doppler US. Diagnostic performances of B-mode US, SWE and Doppler US were calculated to differentiate benign and malignant NMLs.ResultsIn benign NMLs, average Emean and Emax were lower, and low vascularity (no flow or only one vessel flow) was more frequent (Pu2009<u20090.001). When BI-RADS category 4a NMLs were downgraded to category 3 with ‘Emean of 85.1xa0kPa or less’ and/or ‘low vascularity’, specificities increased (69.0–90.5xa0%; Pu2009<u20090.001), without significant loss in sensitivities (97.3–100xa0%). When these 4a NMLs were downgraded by the combination of SWE and Doppler US, all downgraded NMLs (59.3xa0%, 19/32) were confirmed as benign.ConclusionsAddition of SWE and colour Doppler US to B-mode US improved diagnostic performances in differentiating benign and malignant NMLs. This study suggests that the combination of SWE and colour Doppler may help patients with BI-RADS category 4a NMLs avoid unnecessary biopsies.Key Points• B-mode US features of malignant and benign NMLs may overlap.n • SWE and colour Doppler provides useful information about breast NMLs.n • SWE and colour Doppler may decrease unnecessary biopsies of breast NMLs.

Shear wave elastography in the diagnosis of breast non-mass lesions: factors associated with false negative and false positive results

ObjectiveTo investigate factors related to false shear wave elastography (SWE) results for breast non-mass lesions (NMLs) detected by B-mode US.MethodsThis retrospective study enrolled 152 NMLs detected by B-mode US and later pathologically confirmed (79 malignant, 73 benign). All lesions underwent B-mode US and SWE. Quantitative (mean elasticity [Emean]) and qualitative (maximum stiffness colour) SWE parameters were assessed, and ‘Emeanu2009>u200985.1 kPa’ or ‘stiff colour (green to red)’ determined malignancy. Final SWE results were matched to pathology results. Multivariate logistic regression analysis identified factors associated with false SWE results for diagnosis of breast NMLs.ResultsAssociated calcifications (Emean: odds ratio [OR]u2009=u20097.60, Pu2009<u20090.01; maximum stiffness colour: ORu2009=u20096.30, Pu2009=u20090.02), in situ cancer compared to invasive cancer (maximum stiffness colour: ORu2009=u20095.29, Pu2009=u20090.02), and lesion size (Emean: ORu2009=u20090.90, Pu2009<u20090.01; maximum stiffness colour: ORu2009=u20090.91, Pu2009=u20090.01) were significantly associated with false negative SWE results for malignant NMLs. Distance from the nipple (Emean: ORu2009=u20090.84, Pu2009=u20090.03; maximum stiffness colour: ORu2009=u20090.93, Pu2009=u20090.04) was significantly associated with false positive SWE results for benign NMLs.ConclusionsPresence of associated calcifications, absence of the invasive component, and smaller lesion size for malignant NMLs and shorter distance from the nipple for benign NMLs are factors significantly associated with false SWE results.Key points• Calcification and size are associated with false negative SWE in malignant NMLs.• In situ cancer is associated with false negative SWE in malignant NMLs.• Distance from the nipple is associated with false positive SWE in benign NMLs.• These factors need consideration when performing SWE on breast NMLs.

Sonographically Guided Radiofrequency Ablation With and Without a Superficial Saline Injection to Prevent Skin Burns in a Rabbit Model

Our aim was to determine whether sonographically guided radiofrequency ablation with superficial saline injection can minimize thermal injury of the skin without an influence on therapeutic efficacy.