Photon-counting detector CT with an ultra-low-dose contrast media to diagnose a renal pseudoaneurysm: A case report.

A 75-year-old male, weighing 71 kg, was admitted to our institution with anemia related to a subcapsular hematoma after accidental extraction of a nephrostomy catheter. While the patient exhibited the progression of chronic kidney disease, he was not yet on dialysis. His serum creatinine level increased to 6.8 mg/dL, with an estimated glomerular filtration rate of 7.4 mL/min/1.73 m2. Radiologists planned contrast-enhanced photon-counting detector CT (PCD-CT) with an ultra-low-dose contrast media to mitigate the impact on renal function. The contrast media dosage was set at 7.4 gI, which was 82.6% lower that used in the standard protocol for a male weighing 71 kg. Non-contrast-enhanced PCD-CT identified a low-density nodular area within the renal subcapsular hematoma. Contrast-enhanced PCD-CT revealed contrast enhancement in both the early and late phases corresponding to the nodular area. On virtual monoenergetic images, the renal pseudoaneurysm was most clearly delineated at 40 keV. Following the diagnosis of a pseudoaneurysm, transcatheter arterial coil embolization was performed. No subsequent progression of anemia or the deterioration of renal function was observed, showcasing the potential of ultra-low-dose contrast-enhanced PCD-CT for the detection of small vascular abnormalities while minimizing adverse effects on renal function.

Three-compartment spectral diffusion analysis for breast cancer magnetic resonance imaging.

RATIONALE AND OBJECTIVES: To examine the diagnostic performance of a three-compartment diffusion model with the fixed cut-off diffusion coefficient (D) using magnetic resonance spectral diffusion analysis for differentiating between invasive ductal carcinoma (IDC) and ductal carcinoma in situ (DCIS) and compare the conventional apparent D (ADC), and mean kurtosis (MK), with the tissue D (DIVIM), perfusion D (D*IVIM), and perfusion fraction (fIVIM) calculated by conventional intravoxel incoherent motion. PATIENTS AND METHODS: This retrospective study included women who underwent breast MRI with eight b-value diffusion-weighted imaging between February 2019 and March 2022. Spectral diffusion analysis was performed; very-slow, cellular, and perfusion compartments were defined using cut-off Ds of 0.1 × 10-3 and 3.0 × 10-3 mm2/s (static water D). The mean D (Ds, Dc, Dp, respectively) and fraction F (Fs, Fc, Fp, respectively) for each compartment were calculated. ADC and MK values were also calculated; receiver operating characteristic analyses were performed. RESULTS: Histologically confirmed 132 ICD and 62 DCIS (age range 31-87 [53 ± 11] years) were evaluated. The areas under the curve (AUCs) for ADC, MK, DIVIM, D*IVIM, fIVIM, Ds, Dc, Dp, Fs, Fc, and Fp were 0.77, 0.72, 0.77, 0.51, 0.67, 0.54, 0.78, 0.51, 0.57, 0.54, and 0.57, respectively. The AUCs for the model combining very-slow and cellular compartments and the model combining the three compartments were 0.81 each, slightly and significantly higher than for ADC, DIVIM, and Dc (P = 0.09-0.14); and MK (P < 0.05), respectively. CONCLUSION: Three-compartment model analysis using the diffusion spectrum accurately differentiated IDC from DCIS; however, it was not superior to ADC and DIVIM. The diagnostic performance of MK was lower than that of the three-compartment model.

Definitive radiotherapy with stereotactic or IMRT boost with or without radiosensitization strategy for operable breast cancer patients who refuse surgery.

For breast cancer (BC) patients who refused surgery, we developed a definitive treatment employing modern sophisticated radiation techniques. Thirty-eight operable BC patients were treated by conventionally fractionated whole-breast (WB) radiotherapy in combination with stereotactic (for primary tumor) or intensity-modulated (for primary tumor with/without regional lymph nodes [LN]) radiotherapy (IMRT) boost. Standard doses were 50 Gy/25 fractions, 21 Gy/3 fractions and 20 Gy/8 fractions, respectively, for the three radiation modalities. Disease stages were 0 (ductal carcinoma in situ [DCIS]) in seven patients, I in 12, II in 16 and III in three. In 26 patients, intratumoral hydrogen peroxide injection or hyperthermia with oral tegafur-gimeracil-oteracil potassium (S-1) was also used to sensitize the tumors to radiation. Hormonal and standard systemic therapy were administered in 25 and 13 patients, respectively. Complete and partial responses were obtained in 19 patients each; in patients with partial response, no further regrowth of the residual mass was observed, except for two patients who developed local recurrence. During a follow-up of 8-160 months (median, 50 months for living patients), two, one and two patients developed local relapse, sub-clavicular node metastasis and distant metastasis, respectively. The 5-year rates for overall, progression-free and local relapse-free survival were 97.2, 90.9 and 93.4%, respectively. Fourteen patients developed Grade 3 radiation dermatitis but all recovered after treatment. In 47%, the affected breast became better-rounded, and the nipple of the irradiated breast became higher by ≥1 cm than the contralateral nipple. Our method might be a treatment option for operable BC patients.

T-staging of rectal cancer: Utility of single-shot turbo spin-echo diffusion-weighted imaging with T2-weighted images and fusion images.

PURPOSE: The purpose of this study was to evaluate the usefulness of turbo spin-echo (TSE) DWI with fusion images in the T-staging compared with T2-weighted imaging (T2WI) alone and conventional echo-planner imaging (EPI) DWI. METHODS: In this prospective study, 4-mm-thick axial EPI-DWI, TSE-DWI, and T2WI were performed with the same slice locations for 20 patients with rectal cancer. Fusion images of DWI and T2WI were created for both EPI-DWI and TSE-DWI. Ten readers independently diagnosed the T-stages and scored the degree of confidence referring to T2WI alone and then to DWI, T2WI, and fusion images (DWI+T2WI) for each EPI-DWI and TSE-DWI. Visual score assessments of image quality were performed for each DWI. RESULTS: Inter-observer agreement of T-staging for 10 readers was slight on T2WI alone but fair on EPI-DWI+T2WI and excellent on TSE-DWI+T2WI images. No readers gave higher confidence scores for T2WI compared to EPI/TSE-DWI+T2WI and for EPI-DWI+T2WI compared to TSE-DWI+T2WI. In seven pathologically-proven cases, poor, poor to slight, and fair to perfect agreements with the pathological T-stage were observed with T2WI alone, EPI-DWI+T2WI, and TSE-DWI+T2WI, respectively. All readers gave higher scores regarding image distortion and lower scores regarding image noise for TSE-DWI compared to EPI-DWI. For DWI utility, higher scores were assigned for TSE-DWI compared to EPI-DWI in 7 readers and there were no significant differences in the other 3 readers. CONCLUSION: TSE-DWI images might be more appropriate for image fusion with T2WI and rectal cancer T-staging compared with EPI-DWI and T2WI alone.

Utility of CT texture analysis to differentiate olfactory neuroblastoma from sinonasal squamous cell carcinoma.

The purpose of this study was to examine differences in texture features between olfactory neuroblastoma (ONB) and sinonasal squamous cell carcinoma (SCC) on contrast-enhanced CT (CECT) images, and to evaluate the predictive accuracy of texture analysis compared to radiologists' interpretations. Forty-three patients with pathologically-diagnosed primary nasal and paranasal tumor (17 ONB and 26 SCC) were included. We extracted 42 texture features from tumor regions on CECT images obtained before treatment. In univariate analysis, each texture features were compared, with adjustment for multiple comparisons. In multivariate analysis, the elastic net was used to select useful texture features and to construct a texture-based prediction model with leave-one-out cross-validation. The prediction accuracy was compared with two radiologists' visual interpretations. In univariate analysis, significant differences were observed for 28 of 42 texture features between ONB and SCC, with areas under the receiver operating characteristic curve between 0.68 and 0.91 (median: 0.80). In multivariate analysis, the elastic net model selected 18 texture features that contributed to differentiation. It tended to show slightly higher predictive accuracy than radiologists' interpretations (86% and 74%, respectively; P = 0.096). In conclusion, several texture features contributed to differentiation of ONB from SCC, and the texture-based prediction model was considered useful.

Effect of adalimumab on axial manifestations in Japanese patients with psoriatic arthritis: a 24 week prospective, observational study.

OBJECTIVES: PsA is characterized by enthesitis, synovitis and osseous involvement in the peripheral and axial joints. Few studies have examined axial involvement in PsA using imaging techniques. Here we examined axial involvement in PsA patients using MRI. In addition, we determined the efficacy of 24 week adalimumab treatment in improving the MRI findings of spondylitis and sacroiliitis. METHODS: This was a prospective, open-label, single-arm study in patients with PsA. Adalimumab was administered to patients for a total of 24 weeks. MRI examinations were conducted at baseline and at week 24 of adalimumab treatment. RESULTS: Thirty-seven patients with PsA were included in this study. Spondylitis was observed in at least one site of the positive scan in 91% (n = 31) of patients with PsA. The number of arthritic sites in the cervical, thoracic and lumbar regions of the spine was 48, 67 and 53, respectively. All patients had MRI-determined sacroiliitis of grade ≥1 severity while 28 patients (82%) had grade ≥2 sacroiliitis in at least one sacroiliac region. Sacroiliac arthritis was statistically more severe on the right side than on the left side (P < 0.05). In 34 patients with PsA, the thoracic spine was the most common site of spondylitis. In addition, 24 week adalimumab treatment led to an improvement in the mean number of spondylitis sites and the mean grade of sacroiliitis. CONCLUSION: Treatment with adalimumab for 24 weeks resulted in improvement in spondylitis and sacroiliitis.

Corrigendum to "Relapsed multiple myeloma manifesting as extramedullary plasmacytoma of the breast: Imaging findings" [Radiology Case Reports 14 (2019) 584-587].

[This corrects the article DOI: 10.1016/j.radcr.2019.02.018.].

Utility of 70-kV single-energy CT in depicting the extent of breast cancer for preoperative planning.

PURPOSE: To evaluate the detectability of breast cancer and visibility of the tumor extent using 70-kV single-energy contrast-enhanced (CE) breast computed tomography (70-kV CECT) compared with CE breast magnetic resonance imaging (CEMR). METHODS: Between 2013 and 2015, 110 patients with 112 breast cancer lesions who underwent breast surgery after undergoing both 70-kV CECT and CEMR were enrolled. The major axis lengths of the breast lesion were measured and compared with the pathologically determined major axes. Agreement in the measured major axes was evaluated using the intra-class correlation coefficient (ICC). RESULTS: Both 70-kV CECT and CEMR depicted all breast cancer lesions. The mean major axis was 3.0 (95% confidence interval [CI], 2.5-3.4) cm on CECT and 2.9 (2.6-3.3) cm on CEMR. The mean differences between the pathologically and radiologically measured major axes on 70-kV CECT and CEMR were 0.9 (0.7-1.1) and 1.0 (0.8-1.2) cm, respectively. The accuracy of the radiological major axes compared with the pathological major axes was 82.1% and 80.4% on CECT and CEMR, respectively (p = 0.81). The major axes on the two modalities demonstrated moderate agreement (ICC = 0.69, 95% CI 0.58-0.77). Pathologically and radiologically measured major axes on 70-kV CECT and CEMR demonstrated excellent agreement (ICC = 0.91, 95% CI 0.93-0.96). CONCLUSIONS: Low-tube voltage (70-kV) CECT is the preferred modality to identify breast cancer lesions and tumor extent for preoperative planning because it has a similar diagnostic ability to CEMR and can be performed in the supine position.

Digital Mammographic Features of Breast Cancer Recurrences and Benign Lesions Mimicking Malignancy Following Breast-Conserving Surgery and Radiation Therapy.

Mammography after breast-conserving surgery and radiation therapy is an important tool for followup. Early diagnosis of local recurrence enables prompt treatment decisions, which may affect patient prognosis. For complicated post-treatment changes, radiologists sometimes have difficulties in interpreting follow-up mammography. Fat necrosis, dystrophic calcifications, suture calcification features, breast edema, seroma and distorted breast are benign changes related to treatment. These findings may mimic or hide tumor recurrence making it difficult to diagnose recurrences or prevent inappropriate biopsies. Recurrent tumors in follow-up mammography show several typical findings such as increasing asymmetric density, enlarging mass, reappearance of breast edema, and micro-calcifications. The purpose of this pictorial review is to demonstrate and discuss mammographic findings of recurrent tumors and important post-treatment changes that may mimic benign or malignant lesions, also using breast ultrasound images or breast magnetic resonance images. Recognizing post-treatment changes may help radiologists to more effectively identify candidates for suspected local recurrences.

Relapsed multiple myeloma manifesting as extramedullary plasmacytoma of the breast: Imaging findings.

Extramedullary plasmacytoma of the breast (EPB), a manifestation of multiple myeloma (MM), is very rare. It is important to recognize the imaging findings of EPB because it may be the first manifestation of relapsed MM. An 85-year-old woman presented with a lump in her right breast 4 years after the complete remission of MM. She underwent mammography and ultrasonography, which showed an oval circumscribed mass and an irregular circumscribed heterogeneous solid mass, respectively. Following ultrasound-guided vacuum-assisted breast biopsy, this lesion was confirmed to be EPB. Whole-body computed tomography showed multiple new osteolytic lesions and other multiple extramedullary lesions in addition to EPB in the right breast. The final diagnosis was relapsed MM with multiple extramedullary plasmacytoma.

Effects of menstrual cycle on background parenchymal enhancement and detectability of breast cancer on dynamic contrast-enhanced breast MRI: A multicenter study of an Asian population.

PURPOSE: To evaluate the effect of the menstrual cycle on BPE and cancer detectability in an Asian population. MATERIAL AND METHODS: 266 premenopausal patients with regular menstrual cycles from 24 centers were included, and 176 of them were diagnosed by pathology as having breast cancer. Thirty-five patients were examined in the menstrual phase (days 1-4), 105 in the proliferative phase (days 5-14), and 126 in the secretory phase (days 15-30). Measurement of the following signal intensities (SIs) were obtained: breast tissue on the unaffected side on a pre-contrast image (SI1) and an early-phase image (SI2); the SIs of breast tissue on the affected side on a pre-contrast image (SI3) and an early-phase image (SI4); and the SIs of breast cancer on a pre-contrast image (SI5) and an early-phase image (SI6). We calculated the BPE ratio, i.e., (SI2- SI1)/SI1 and the cancer/background enhancement ratio (C/B) ratio, i.e., (SI6- SI5) / (SI4- SI3). The BPE was classified as minimal, mild, moderate, or marked, and the cancer detectability was classified as excellent, good, or poor independently by two radiologists. RESULTS: The average C/B ratio was 20.1, 15.7, and 9.1 at the menstrual, proliferative, and secretory phases (p < 0.001). BPE was determined as moderate or marked in 0% and 5.4% at the menstrual phase, 10.3% and 11.0% at the proliferative phase, and 17.5% and 21.7% at the secretory phase by the two observers, respectively (p = 0.01, p = 0.01). The detectability of breast cancer was classified as poor in 0% and 0%, 1.4% and 13.0%, and 8.0% and 22.1% at the menstrual, proliferative, and secretory phases by the two observers, respectively (p = 0.07, p = 0.02). CONCLUSION: The menstrual phase and the proliferative phase seem to be suitable for breast MRI of Asian women.

Internal mammary lymph node metastases in breast cancer: what should radiologists know?

The internal mammary lymph node (IMLN) chain is a pathway through which breast lymphatic drainage flows. The internal mammary lymphatic vessel runs around the internal mammary artery and veins with IMLN in the parasternal intercostal spaces. IMLN metastasis, which forms a part of clinical TNM staging, may negatively affect the prognosis of primary breast cancer patients. IMLN metastasis is clinically detected using ultrasound, computed tomography, magnetic resonance imaging, and 18F-deoxyglucose positron emission tomography computed tomography. The uptake of radioactive tracers in IMLN with clinically negative axillary lymph nodes is often identified using sentinel lymph node mapping (SLNM) in primary breast cancer patients. The indication for IMLN biopsy or resection that is clinically detected or visualized using SLNM is controversial. The clinically suspicious IMLN may be considered for ultrasound-guided fine-needle aspiration. First IMLN recurrence needs to be biopsied. Irradiation of the breast, chest wall, and/or regional nodal irradiation, including IMLN, following lumpectomy or postmastectomy is recommended. Although radiation therapy for IMLN recurrence may improve clinical outcomes, it is also associated with pulmonary and cardiac toxicities. This review covers the local anatomy of IMLN, lymph drainage and image findings of IMLN with a discussion.

Utility of the variable flip angle 3D fast-spin echo (isoFSE) sequence on 3T MR for diagnosing vertebrobasilar artery dissection.

We aimed to investigate the utility of the isoFSE sequence, one of the variable flip angle 3D fast-spin echo sequences, on 3T-MR for displaying vessel walls and diagnosing vertebrobasilar artery dissection (VAD). We retrospectively evaluated 12 initial and 28 follow-up images from 12 patients diagnosed with either intracranial VAD or carotid artery dissection. The image quality for displaying the vessel wall was scored using a five-point scale (1 poor, 5 excellent) on initial T1-weighted isoFSE images for each region of the arteries. The intracranial artery dissection findings assessed at time points after onset were evaluated on initial and follow-up T1/T2-weighted isoFSE images. For small arteries, including the anterior/posterior inferior cerebellar artery, similar high scores were obtained on both unenhanced and contrast-enhanced T1-weighted isoFSE images (average: 4.7-5.0, p > 0.2). On unenhanced images, dissected vertebral arteries showed significantly lower scores than non-dissected vertebral arteries for both readers (p = 0.017 and 0.015, respectively), but the scores were high (3.9 and 4.0, respectively). Definitive findings of VAD were observed on the initial images except in one case. For all cases, definitive findings were seen on at least one of the initial or follow-up images. Temporal changes in the findings could be observed for all cases. In conclusion, we showed favorable wall visualization on T1-weighted isoFSE images and the utility of follow-up imaging using unenhanced-T1/T2-weighted and contrast-enhanced T1-weighted isoFSE sequences with acceptable scan times, which could promote the regular use of 3D black-blood vessel wall imaging.

Multiparametric MRI for differentiation of borderline ovarian tumors from stage I malignant epithelial ovarian tumors using multivariate logistic regression analysis.

OBJECTIVE: To assess the value of contrast-enhanced MRI, apparent diffusion coefficient (ADC) measurement, and CA-125 measurement for differentiating borderline ovarian tumors (BOTs) from stage I malignant epithelial ovarian tumors (MEOTs). MATERIAL AND METHODS: This retrospective study included 43 patients with BOTs and 43 patients with stage I MEOTs who underwent contrast-enhanced MRI with DWI and CA-125 analysis. Two radiologists evaluated the MRI findings in consensus. Univariate and multivariate analyses were performed to detect the best predictor variables for MEOTs. RESULTS: Mixed cystic/solid and predominantly solid appearances, as well as thickened irregular septa, were more frequent in MEOTs. A papillary architecture and internal branching (PA&IB) pattern was more frequent in BOTs. MEOTs had thicker walls and septa, larger solid components, and higher CA-125 values. The mean ADC value of solid components (ADCmean) and minimum ADC value of whole lesions (ADCmin) were lower in MEOTs. Multivariate analysis revealed that ADCmin and maximum diameter of the solid components were independent indicators of MEOTs with an AUC, sensitivity, and specificity of 0.86, 81%, and 84%, respectively. CONCLUSION: ADCmin and maximum diameter of solid components were useful for differentiating BOTs from MEOTs.

Usefulness of 3D balanced turbo-field-echo MR sequence evaluating the branching pattern of the intrahepatic bile ducts: comparison with drip infusion CT cholangiography.

PURPOSE: For liver surgery, it is crucial to preoperatively examine the course of the right posterior bile duct. While MR cholangiopancreatography (MRCP) can only visualize the bile ducts, 3D balanced turbo-field-echo (BTFE) sequence clearly depicts the bile ducts and portal veins as well as drip infusion CT cholangiography (DIC-CT), without contrast media. We evaluated whether BTFE could substitute for DIC-CT. MATERIALS AND METHODS: Thirty patients undergoing MRCP and BTFE on 1.5-T MR and DIC-CT were evaluated. Two readers retrospectively evaluated the branching pattern (supra-type: A-C or infra-type: D-E) and scored the degree of confidence and motion artifacts using a 3-point scale for the three 2-mm-thick reconstructed images. RESULTS: The bile duct diameter did not differ between DIC-CT and MRCP (p = 0.07). Five patients (17%) had intrahepatic biliary dilatation (>3 mm). The A, B, C, D, and E types were diagnosed in 21, 6, 1, 1, and 1 patient, respectively (28 supra-types and 2 infra-types) on DIC-CT. For DIC-CT, MRCP, and BTFE, the mean motion artifact scores were 3.0/3.0, 2.7/2.6, and 2.9/2.8, respectively. The mean diagnostic confidence scores were 2.9/2.9, 2.4/2.4, and 2.9/2.8, respectively, with no difference between DIC-CT and BTFE. The concordance between DIC-CT and BTFE was high (infra- or supra-type: κ = 1.00/1.00, A-E: κ = 0.86/0.66), but it was poor between DIC-CT and MRCP (infra- or supra-type: κ = 0.35/-0.05, A-E: κ = 0.33/0.41) for both readers. CONCLUSIONS: Similar to DIC-CT, the BTFE MR sequence had high diagnostic accuracy regarding the branching pattern of the intrahepatic bile duct, especially for the supra/infraportal type.

Diagnostic utility of a computer-aided diagnosis system for whole-body bone scintigraphy to detect bone metastasis in breast cancer patients.

OBJECTIVE: To compare the diagnostic ability of planar images (PI) and images obtained by a computer-aided diagnosis (CAD) system (Viewer for Standardized Bone Scintigraphies; VSBONE) of whole-body bone scintigraphy for detecting bone metastases in breast cancer patients. METHODS: 81 women (median: 56 years; range: 32-79) with a history of breast cancer were included in this study. They underwent whole-body bone scintigraphy after intravenous injection of 740 MBq technetium-99m hydroxymethylene diphosphonate. A total of 1066 bones (162 regions of the skull, 657 regions of the spine and pelvis, 223 regions of the sternum and rib, 18 regions of the upper extremities, and 6 regions of the lower extremities) were analyzed. The PI alone, VSBONE images alone, and both PI and VSBONE images (PI + VSBONE) were interpreted independently by two radiologists to diagnose bone metastases, which were then confirmed by magnetic resonance imaging. The sensitivity and specificity for each modality were analyzed using Fisher's exact and McNemar tests. Inter-reviewer agreement was evaluated using a kappa statistic. RESULTS: Bone metastases were confirmed in 43 patients with 442 positive lesions. The average sensitivity of PI, VSBONE images, and PI + VSBONE images was 40.8, 50.2, and 61.8 %, respectively. The average specificity was 97.8, 97.5, and 97.6 %, respectively. The kappa scores were 0.62 for PI, 0.69 for VSBONE, and 0.77 for PI + VSBONE. CONCLUSIONS: VSBONE was superior to PI in regard to sensitivity for detecting bone metastases in breast cancer patients. However, an improved CAD system is required to decrease the number of false-negative results.

Digital mammography versus digital breast tomosynthesis for detection of breast cancer in the intraoperative specimen during breast-conserving surgery.

PURPOSE: To compare the diagnostic ability of specimen radiography using digital mammography (DM) and digital breast tomosynthesis (DBT) for detecting breast cancer and evaluating its extension in the intraoperative specimen. METHODS: Sixty-five specimens from 65 women (median 62 years; range 34-86) obtained during breast-conserving surgery were prospectively investigated. Specimens underwent DM (25-40 kVp, 12-322 mA s) and DBT (25-34 kVp, 13-137 mA) in two orthogonal planes, anteroposterior (AP) and latero-lateral (LL). Images were interpreted by a radiologist to detect invasive lesions and their extensive intraductal components (EIC) or ductal carcinomas in situ (DCIS); afterwards, they were compared with histopathological findings. RESULTS: In AP views, 96 % of the invasive lesions were detected by both the methods. Of the EICs, 55 and 65 % were detected by DM and DBT, respectively (P = 0.61). Of the DICSs, 31 and 38 % were detected by DM and DBT, respectively (P > 0.99). In LL views, 71 and 13 % of the invasive lesions were detected by DBT and DM, respectively (P < 0.0001). Of the EICs, 42 and 10 % were detected by DBT and DM, respectively (P = 0.0078). Of the 13 DCISs, 42 and 8 % were detected by DBT and DM, respectively (P = 0.32). The whole lesion and contour could be delineated in 45 % by DBT and in 6.2 % by DM (P < 0.0001). CONCLUSIONS: DBT could detect breast cancer more accurately than DM in LL views, indicating its potential to more precisely diagnose vertical invasion.

Multi-detector row CT-guided marking technique for breast-conserving therapy of early breast cancer: margin positivity and local control rates.

BACKGROUND: In breast-conserving surgery (BCS), image-guided marking of the tumor border is important for preventing local recurrence and achieving a good cosmetic outcome. The purpose of this study was to evaluate the usefulness of multi-detector row computed tomography (MDCT)-guided marking technique before BCS in patients in whom ultrasound (US)-guided marking was not feasible. METHODS: Between 2004 and 2010, 94 lesions underwent contrast-enhanced MDCT-guided marking. Margin positivity and local control rates were compared with those of 149 lesions undergoing US-guided marking during the same period. RESULTS: In 21 lesions undergoing CT marking (22 %) and 20 lesions undergoing US marking (13 %), a negative resection margin could not be achieved, and hence the marking was judged as unsuccessful. Eighty-four lesions of the CT marking group and 119 of the US marking group received postoperative radiotherapy with 50 Gy in 25 fractions with or without an additional 10-Gy boost to the tumor bed. The remaining 10 and 30 patients, respectively, did not receive radiotherapy. The median follow-up period was 54 and 51 months for patients with CT marking and those with US marking, respectively. At 4 postoperative years, the local control rate was 96.5 % for patients with CT marking and 97.3 % for those with US marking (P = 0.89). CONCLUSIONS: The MDCT marking technique appears to be a valuable tool for determining the surgical margin for BCS in patients in whom ultrasound marking cannot be performed. Combining this technique with appropriate postoperative radiation therapy is expected to yield reasonably high local control rates.

Characteristic MRI findings of sarcomatoid renal cell carcinoma dedifferentiated from clear cell renal carcinoma: radiological-pathological correlation.

PURPOSE: To evaluate MRI findings of sarcomatoid renal cell carcinoma (SRCC). MATERIAL AND METHODS: Eleven patients with pathologically proven SRCC dedifferentiated from clear cell renal carcinoma (CCRC) underwent preoperative renal MRI. The MRI findings were compared with histological findings. On MRI, the following findings were evaluated: the presence and distribution of areas showing heterogeneous iso to high signal intensity (SI) on T2-weighted images (T2HIA) and conspicuously low SI areas (T2LIA) compared to normal renal cortex, areas showing high SI on T1-weighted images and unenhanced areas on dynamic contrast-enhanced images, disruption of pseudocapsule, and the SIs of T2HIA and T2LIA on diffusion-weighted imaging (DWI). The apparent diffusion coefficient (ADC) values and SI ratios to muscle on dynamic contrast-enhanced imaging (DCE) were compared between T2HIA and T2LIA using the t test. RESULTS: The distribution of T2HIA and T2LIA was as follows: a mixed pattern alone in five, nodular T2LIA pattern alone in one, both mixed and nodular T2LIA patterns in four, and a separated pattern in one. Disruption of the pseudocapsule was seen in all cases. The imaging findings suggesting intratumoral hemorrhage and necrosis were seen in 18% and 63%, respectively. The SIs of T2HIA and T2LIA were low intermediate and high on DWI, respectively. T2LIA and T2HIA corresponded to the components of SRCC with abundant fibrosis and CCRC, respectively. T2LIA showed significantly lower enhancement at all DCE phases and a lower ADC value than T2HIA. CONCLUSION: The presence of T2LIA corresponding to the area showing a hypovascular nature and markedly restricted diffusion might be characteristic findings of SRCC. Intratumoral hemorrhage and necrosis were seen, but they were not specific findings.