Correlations between intravoxel incoherent motion (IVIM) parameters and histological findings in rectal cancer: preliminary results.

Our purpose was to correlate different intravoxel incoherent motion (IVIM), histopathological and clinical parameters in rectal cancer. 17 patients with histologically proven rectal cancer investigated on a 3.T device were included into the study. DWI was performed using a multi-slice single-shot echo-planar imaging sequence with b values of 0, 50, 200, 500 and 1000 s/mm.2 A polygonal region of interest was drawn within the tumors on every b image. The following parameters were retrieved from IVIM: apparent diffusion coefficient (ADC), true diffusion (D), pseudo diffusion coefficient (D*), perfusion factor (f), and relative perfusion f·D*. In every case, cell count, nucleic areas, proliferation index KI 67, and microvessel density were estimated on histopathological specimens. Pearson's correlation coefficient was used to analyze the association between the parameters. ADC correlated well with KI 67 index and D tended to correlate with cell count and KI 67. ADC and D tended to correlate with total nucleic area. The perfusion factor f correlated well with stained vessel area, total vessel area, and vessel count. D* and fD* correlated with mean vessel diameter. Distant metastasized tumors had higher D* and fD* values. IVIM parameter reflected different clinical and histopathological features in rectal cancer.

Correlation Between Aquaporin 4 Expression and Different DWI Parameters in Grade I Meningioma.

PURPOSE: Diffusion-weighted imaging (DWI) measures water diffusion in biological tissues. Cellular water transport depends on aquaporins (AQPs). The expression of aquaporins might differ in several pathologic disorders. Therefore, the aim of this study was to evaluate the associations between AQP4 expression and different DWI parameters in meningioma. PROCEDURES: Twenty-three patients with meningioma grade I were included in this retrospective study. DWI was obtained with three b values (0; 500; 1000) using a 1.5-T device. ADCmean, ADCmin, ADCmax, and true diffusion coefficients (D) were obtained in every patient. Aquaporin 4 expression was quantified immunohistochemically in four immunoreactivity levels. RESULTS: The estimated DWI parameters (mean value ± standard deviation, 10-3 mm2 s-1) of the tumors were as follows: ADCmin 0.67 ± 0.16, ADCmean 0.94 ± 0.23, ADCmax 1.29 ± 0.50, and D 0.65 ± 0.23. The mean level of the AQP4 expression was 2.02 ± 0.75 points. A statistically significant correlation between AQP4 expression and ADCmax was identified (r = 0.508, p = 0.013). No significant correlations between AQP4 and other DWI parameters were found. CONCLUSIONS: A clear correlation between AQP4 expression and ADCmax values in grade I meningioma was identified. There were no significant correlations between AQP4 expression and other DWI parameters, such as ADCmin, ADCmean, and D.

Radiological features of metastases to the thyroid.

BACKGROUND: Thyroid metastases (TM) are uncommon. Dependent on study design, the reported frequency of TM is in the range of 0.1-6% in different analyses. While clinical and histopathological features of TM were well described in the literature, radiological publications consist predominantly of isolated case reports or small series. PURPOSE: To estimate the prevalence, clinical signs, and radiological appearances of TM. MATERIAL AND METHODS: From 1997 to 2013, a total of 8849 patients with various disorders of the thyroid gland were treated in our institution. In 33 patients TM were diagnosed. Ultrasound (US) images were available in all patients, computed tomography (CT) of the neck in 16 patients, and magnetic resonance imaging (MRI) in nine patients. RESULTS: Clinically, most patients (85%) presented with a painless neck mass. Primary tumors were renal cell carcinoma (79%), colorectal cancer (12%), lung cancer (3%), rhabdomyosarcoma (3%), and breast carcinoma (3%). On US, most lesions were irregular in shape with inhomogenous texture. On CT, all TM were hypodense. On T1-weighted images, most TM were inhomogenously iso-to-hyperintense in comparison to the normal thyroid tissue, and slightly hyperintense on T2-weighted images with an inhomogenous contrast enhancement. CONCLUSION: The prevalence of TM was 0.4%. Most of the TM originated from renal cell carcinoma. The identified radiological features of TM should be taken into consideration in the differential diagnosis of thyroid lesions.

Diffusion-Weighted Imaging in Meningioma: Prediction of Tumor Grade and Association with Histopathological Parameters.

OBJECTIVES: To analyze diffusion-weighted imaging (DWI) findings of meningiomas and to compare them with tumor grade, cell count, and proliferation index and to test a possibility of use of apparent diffusion coefficient (ADC) to differentiate benign from atypical/malignant tumors. METHODS: Forty-nine meningiomas were analyzed. DWI was done using a multislice single-shot echo-planar imaging sequence. A polygonal region of interest was drawn on ADC maps around the margin of the lesion. In all lesions, minimal ADC values (ADCmin) and mean ADC values (ADCmean) were estimated. Normalized ADC (NADC) was calculated in every case as a ratio ADCmean meningioma/ADCmean white matter. All meningiomas were surgically resected and analyzed histopathologically. The tumor proliferation index was estimated on Ki-67 antigen-stained specimens. Cell density was calculated. Collected data were evaluated by means of descriptive statistics. Analyses of ADC/NADC values were performed by means of two-sided t tests. RESULTS: The mean ADCmean value was higher in grade I meningiomas in comparison to grade II/III tumors (0.96 vs 0.80 × 10(-3) mm(2)s(-1), P = .006). Grade II/III meningiomas showed lower NADC values in comparison to grade I tumors (1.05 vs 1.26, P = .015). There was no significant difference in ADCmin values between grade I and II/III tumors (0.69 vs 0.63 × 10(-3) mm(2)s(-1), P = .539). The estimated cell count varied from 486 to 2091 (mean value, 1158.20 ± 333.74; median value, 1108). There were no significant differences in cell count between grade I and grade II/III tumors (1163.93 vs 1123.86 cells, P = .77). The mean level of the proliferation index was 4.78 ± 5.08%, the range was 1% to 18%, and the median value was 2%. The proliferation index was statistically significant higher in grade II/III meningiomas in comparison to grade I tumors (15.43% vs 3.00%, P = .001). Ki-67 was negatively associated with ADCmean (r = -0.61, P < .001) and NADC (r = -0.60, P < .001). No significant correlations between cell count and ADCmean (r = -0.20, P = .164) or NADC (r = -0.25, P = .079) were found. ADCmin correlated statistically significant with cell count (r = -0.44, P = .002) but not with Ki-67 (r = -0.22, P = .129). Furthermore, the association between ADCmin and cell count was stronger in grade II/III tumors (r = -0.79, P = .036) versus grade I meningiomas (r = -0.41, P = .008). An ADCmean value of less than 0.85 × 10(-3) mm(2)s(-1) was determined as the threshold in differentiating between grade I and grade II/III meningiomas (sensitivity 72.9%, specificity 73.1%, accuracy 73.0%). The positive and negative predictive values were 33.3% and 96.8%, respectively. The same threshold ADCmean value was used in differentiating between tumors with Ki-67 level ≥5% and meningiomas with low proliferation index (Ki-67 <5%). This threshold yielded a sensitivity of 70.6%, a specificity of 81.2%, and an accuracy of 77.6%. The positive and negative predictive values were 66.6% and 83.9%, respectively. CONCLUSIONS: Grade II/III tumors had lower ADCmean values than grade I meningiomas. ADCmean correlated negatively with tumor proliferation index and ADCmin with tumor cell count. These associations were different in several meningiomas. ADCmean can be used for distinguishing between benign and atypical/malignant tumors.

Correlation Between Different ADC Fractions, Cell Count, Ki-67, Total Nucleic Areas and Average Nucleic Areas in Meningothelial Meningiomas.

BACKGROUND: Meningioma is the most common intracranial tumor. The aim of the present study was to correlate apparent diffusion coefficient (ADC) values with cellularity, Ki-67 and nucleic area in meningioma cases. PATIENTS AND METHODS: Twenty-four meningothelial meningiomas were included in the study. Diffusion-weighted imaging was performed using a multi-slice single-shot echo-planar imaging sequence. In all lesions minimal ADC values (ADCmin), mean ADC values (ADCmean), and maximal ADC values (ADCmax) were estimated. Additionally, true ADC values (D) were calculated. All tumors were resected and analyzed histopathologically. The tumor proliferation index was estimated on Ki-67 antigen-stained specimens. Cell density was calculated in every case as an average cell count per five high-power fields. All histological samples were analyzed for estimation of nucleic size and nucleic area. The ImageJ software 1.48v was used for analysis. Analyses of the estimated parameter were performed by means of two-sided t-tests. Correlation analysis was performed using the Pearson's product moment correlation. RESULTS: The mean values of ADCmin, ADCmean, ADCmax, and D were 0.64±0.11, 0.89±0.13, 1.15±0.27, and 0.75±0.20×10-3 mm(2)s(-1), respectively. The estimated mean cell count was 1160.08±33.86 cells and the mean level of the proliferation index was 3.46±2.84%. The mean values of average nucleic area and total nucleic area were 65.42±19.38 µm(2) and 64481.87±21120.02 µm(2), respectively ADCmean correlated significant with Ki-67 level, average nucleic area, and total nucleic area, but not with cell count. ADCmin and D correlated significant with cell count and total nucleic area, but not with Ki-67. D was also associated with average nucleic area. ADCmax correlated slightly with cell count. CONCLUSION: Several relationships between ADC and histological parameters in meningioma were assessed. ADCmean was negatively associated with Ki-67 level, average nucleic area, and total nucleic area. There was no significant correlation between ADCmean and cell count. ADCmin and D correlated well with total nucleic areas and cell count, but not with Ki-67. ADCmax correlated slightly with cell count.

Primary Thyroid Sarcoma: A Systematic Review.

Different types of malignant tumors can occur within the thyroid. Primary cancer is the most common type of thyroid malignancy. Non-epithelial malignancies can also arise within the thyroid. The aim of the present study was to analyze clinical and radiological characteristics of reported primary thyroid sarcomas (PTS), based on a large sample of cases. The PubMed database was screened for articles from between 1990 and 2014. Overall, 86 articles with 142 patients were identified. Ultrasound evaluation was reported for 36 patients. Data regarding computed tomography of the neck were available for 29 cases. Magnetic resonance imaging was performed for eight patients. The following data were retrieved for the identified sarcomas: localization, size, homogeneity, internal texture, and margin characteristics. In most cases, PTS occurred in patients over 40 years of age, with a peak incidence for the group aged 60-79 years. Angiosarcoma was diagnosed in 29 cases (20.4%), followed by malignant hemangioendothelioma (n=23, 16.3%), malignant fibrous histiocytoma (n=20, 14.1%), leiomyosarcoma (n=16, 11.3%), and fibrosarcoma (n=13, 9.2%). In most patients (n=113, 79.6%), PTS manifested clinically as a painless goiter. On ultrasound, PTS were predominantly mixed hypo-to-hyperechoic in comparison to the normal thyroid tissue. On non-contrast computed tomography, most sarcomas were inhomogeneous hypo-to-hyperdense. On post-contrast magnetic resonance images, most sarcomas showed marked non-homogenous enhancement. In 26.8%, infiltration of the adjacent organs was seen. The trachea or esophagus was affected more frequently in patients with malignant histiocytoma and liposarcoma. Different strategies were used in the treatment of PTS. Our analysis provides clinical and radiological characteristics of PTS. The described features should be taken into consideration in the differential diagnosis of thyroid tumors.

Comparison of diffusion-weighted imaging findings in brain metastases of different origin.

Our purpose was to estimate apparent diffusion coefficient (ADC) values from brain metastases (BMs). Our patient sample included 159 patients with 948 BMs. Magnetic resonance imaging was obtained with a 1.5-T device. For diffusion-weighted imaging, a multislice single-shot echo-planar imaging sequence was used (b values of 0, 500, and 1000 s/mm(2)). The mean ADC value of BMs was 0.98 ± 0.32 × 10(-3) mm(2) s(-1). A total of 72.8% of BM lesions showed ADC values under 0.90 × 10(-3) mm(2) s(-1). Small-cell lung cancer had the lowest ADC values (0.86 ± 0.27) in comparison to BMs from non-small-cell lung cancer (1.17 ± 0.49), breast carcinoma (0.97 ± 0.21), and malignant melanoma (0.99 ± 0.36).

Intramuscular leukemic relapse: clinical signs and imaging findings. A multicentric analysis.

OBJECTIVE: Leukemia is a group of malignant diseases involving peripheral blood and bone marrow. Extramedullary tumor manifestation in leukemia can also occur. They more often involve lymph nodes, skin, and bones. Intramuscular leukemic relapse (ILR) is very unusual. The aim of this analysis was to summarize the reported data regarding clinical signs and radiological features of ILR. MATERIAL AND METHODS: The PubMed database was searched for publications related to ILR. After an analysis of all identified articles, 20 publications matched the inclusion criteria. The authors of the 20 publications were contacted and provided imaging of their cases for review. The following were recorded: age, gender, primary diagnosis, clinical signs, pattern, localization and size of the intramuscular leukemic relapse. Images of 16 patients were provided [8 computer tomographic (CT) images and 15 magnetic resonance images, MRI]. Furthermore, one patient with ILR was identified in our institutional database. Therefore, images of 17 patients were available for further analysis. RESULTS: Overall, 32 cases with ILR were included in the analysis. In most cases acute myeloid leukemia was diagnosed. Most ILRs were localized in the extremities (44 %) and in the extraocular muscles (44 %). Clinically, ILR manifested as local pain, swelling and muscle weakness. Radiologically, ILR presented most frequently with diffuse muscle infiltration. On postcontrast CT/MRI, most lesions demonstrated homogeneous enhancement. ILRs were hypo-/isointense on T1w and hyperintense on T2w images. CONCLUSION: ILR manifests commonly as focal pain, swelling and muscle weakness. ILR predominantly involved the extraocular musculature and the extremities. Radiologically, diffuse muscle infiltration was the most common imaging finding.

Pulmonary embolism in oncologic patients: frequency and embolus burden of symptomatic and unsuspected events.

BACKGROUND: Pulmonary embolism (PE) is a common cause of morbidity and mortality in oncologic patients. Furthermore, PE is an unsuspected finding in many cases. PURPOSE: To determine the frequency and embolus burden of PE in a consecutive oncologic patient group including symptomatic as well as incidental and initially unreported events. MATERIAL AND METHODS: In a retrospective, single-center study from June 2005 to January 2010 all patients with an oncologic disease (ICD-10 code C00 to C96) that received at least one contrast-enhanced computed tomography (CT) examination of the chest were reviewed. The study group included 3270 patients with 6780 examinations. A validated pulmonary artery obstruction index (Mastora score) was used to assess embolus burden. RESULTS: PE was found in 240 of 3270 (7.3%) oncologic patients. The frequency was highly variable among different malignancies ranging from 0% to 25%. In the present study about half of all PE were unsuspected. The mean embolus burden was significantly higher in symptomatic PE than in unsuspected PE (P <0.001). The risk of developing a PE was 1.5 times higher in patients with metastases compared to patients without metastases (P <0.005). Age and sex had no influence on PE risk and embolus burden. CONCLUSION: PE is a frequent unsuspected finding in staging examinations: particularly in patients with malignancies of the ovary, brain, and pancreas, and in patients with metastases. Therefore, the status of the pulmonary vasculature should be assessed in every staging examination that includes the chest. The effect of therapeutic actions on PE events and the unsuspected finding of PE in follow-up CT examinations require further prospective studies.

Muscle metastases: comparison of features in different primary tumours.

BACKGROUND: Muscle metastases (MM) from solid tumours are rare. The aim of this study was to describe radiological features of MM, and to compare their patterns in different malignancies. METHODS: A retrospective search in the statistical database of our institution revealed 61 cases of MM. Additionally, a retrospective search in Pubmed database was performed. Together with our cases the present analysis comprises 461 patients (682 MM). RESULTS: MM derived from the following malignancies: lung cancer (25.1%), gastrointestinal tumours (21.0%), and urological tumours (13.2%). Other neoplasias with MM were rare. MM were localised most frequently in the thigh muscles, the extraocular musculature, and the gluteal and paravertebral muscles. The localisation of MM was different in several primary malignancies. CONCLUSION: MM present with a broad spectrum of radiological features. Different CT imaging findings of MM were observed in different primary tumours. The localisation of MM also varies with different primary malignancies.

Intramammary metastases: comparison of mammographic and ultrasound features.

PURPOSE: To describe the mammographical and ultrasound features of IM, and to compare radiological patterns of IM arising from different malignancies. MATERIALS AND METHODS: A retrospective search in the statistical database of our institution from January 2000 to December 2009 revealed 51 cases of intramammary metastases from solid malignancies. Additionally, a retrospective search in the Pubmed database was performed. Publications in the time interval from 1980 to 2010 were considered. After thorough analysis, 119 articles with 229 patients were involved in the study. Therefore, together with our cases our analysis comprises 280 patients. Mammographic and ultrasound findings of different IM were analyzed. RESULTS: The detected metastases showed two main radiological patterns: intramammary masses (81.5%) and architectural distortion (18.5%). Carcinomas of the stomach caused more frequently an architectural distortion, whereas other malignancies tended to present as intramammary masses. The size of the masses ranged from 2 to 104 mm. The largest lesions occurred in rhabdomyosarcoma, followed by hepatocellular carcinoma and squamous cell carcinomas of the head and neck region. The smallest lesions arose from malignancies of the thyroid gland carcinoma. Most IM showed circumscribed margins, while breast lesions in rhabdomyosarcoma were rather microlobulated. On ultrasound, IM from lung cancer were usually inhomogenously hypoechoic with circumscribed margins and showed posterior shadowing in almost 50% of the cases. Breast metastases from ovarian carcinoma had typically microlobulated margins and posterior enhancement. CONCLUSION: IM can present with a broad spectrum of radiological features. Their imaging findings vary depending on the primary tumor.

Imaging of nonthrombotic pulmonary embolism: biological materials, nonbiological materials, and foreign bodies.

Nonthrombotic pulmonary embolism is defined as embolization to the pulmonary circulation caused by a wide range of substances of endogenous and exogenous biological and nonbiological origin and foreign bodies. It is an underestimated cause of acute and chronic embolism. Symptoms cover the entire spectrum from asymptomatic patients to sudden death. In addition to obstruction of the pulmonary vasculature there may be an inflammatory cascade that deteriorates vascular, pulmonary and cardiac function. In most cases the patient history and radiological imaging reveals the true nature of the patient's condition. The purpose of this article is to give the reader a survey on pathophysiology, typical clinical and radiological findings in different forms of nonthrombotic pulmonary embolism. The spectrum of forms presented here includes pulmonary embolism with biological materials (amniotic fluid, trophoblast material, endogenous tissue like bone and brain, fat, Echinococcus granulosus, septic emboli and tumor cells); nonbiological materials (cement, gas, iodinated oil, glue, metallic mercury, radiotracer, silicone, talc, cotton, and hyaluronic acid); and foreign bodies (lost intravascular objects, bullets, catheter fragments, intraoperative material, radioactive seeds, and ventriculoperitoneal shunts).

Radio-opacity and incidental identified mechanical complications of totally implantable venous access devices placed in the chest.

BACKGROUND: Totally implantable venous access devices (TIVAD) may be associated with different complications. Certain mechanical port disorders can easily be diagnosed on chest radiographs if the implanted systems are radiopaque and well visible. There are no reports regarding the visibility of TIVAD on chest X-rays. PURPOSE: To assess the radio opacity of TIVAD implanted in the chest as well as type and frequency of mechanical complications of ports on chest X-ray images. MATERIAL AND METHODS: Chest X-rays of 985 patients from the time period 2007-2009 were analyzed retrospectively. In these patients 1190 TIVAD were inserted. All parts of the TIVAD, i.e. port chamber, connection, and port catheter, were checked for their visibility on chest radiographs. An opacity score was used here as follows: ++ well visible; + visible; - partly or completely invisible. Mechanical complications of TIVAD incidentally detected on chest X-ray were also analyzed retrospectively. RESULTS: Nineteen TIVAD models with diverse configuration and visibility of port chambers, connections, and catheters were identified in our study. Eighty-eight percent of the analyzed port systems were well visible or visible on chest radiographs. Twelve percent of the port chambers and catheters were partly visible or completely invisible. In 9% of the TIVAD, different mechanical complications were diagnosed on chest X-ray images. CONCLUSION: TIVADs should be evaluated carefully on every chest X-ray. Ideally, they should be radio-opaque and well visible on thoracic X-ray images. Unfortunately, this is not always the case. Therefore, manufacturers of TIVAD should take into consideration to use exclusively radio-opaque materials that allow sufficient visibility of each port component on chest radiographs.

Prevalence and imaging of hepatic involvement in malignant lymphoproliferative disease.

From January 2005 to January 2010, 668 consecutive patients with lymphoproliferative disease were retrospectively identified. Hepatic infiltration was present at initial staging in patients with non-Hodgkin's lymphoma [12 of 364=3.3%; age median=45; male:female (M:F)=10:2] but also Hodgkin's disease (5 of 41=12.2%; age median=19; M:F=0:5) and multiple myeloma (3 of 162=1.8%; age median=60; M:F=2:1). There were no cases of hepatic infiltration in 101 patients with leukemia. There are typical radiological patterns of hepatic involvement in lymphoproliferative disease with typical lesions characteristics.

Prevalence and patterns of renal involvement in imaging of malignant lymphoproliferative diseases.

BACKGROUND: Renal involvement in patients with lymphoproliferative disease is an uncommon radiological finding. PURPOSE: To determine its prevalence and radiological appearances in a patient population. MATERIAL AND METHODS: All forms of lymphoproliferative disease (ICD: C81-C96) were considered. From January 2005 to January 2010, 668 consecutive patients with lymphoproliferative disease were identified with the help of the radiological database and patient records. Inclusion criteria were complete staging including appropriate CT scan and/or MRI. All stored images (initial staging and follow-up examinations) were reviewed. RESULTS: Review of all stored images revealed renal infiltration in patients with non-Hodgkin lymphoma (11 of 364 = 3.0%; median age = 65 years, m:f = 6:5) but also multiple myeloma (2 of 162 = 1.2%; median age = 72 years; m:f = 1:1) and leukemia (5 of 101 = 4.9%; median age = 12 years; m:f = 2:3). There were no cases of renal infiltration in 41 patients with Hodgkin's disease. In total there were six patients with solitary lesions, five patients with diffuse renal enlargement, four patients with perirenal lesions, and two patients with direct invasion of the kidney. CONCLUSION: In leukemia the most common imaging pattern is diffuse enlargement. In the other subtypes of lymphoproliferative disease no specific correlation between typical CT patterns and subtype of lymphoproliferative disease can be found. The prevalence of renal involvement is in line with earlier studies. Contrary to earlier reports, multiple lesions were not found to be a common pattern.

Late sequelae of retained foreign bodies after world war II missile injuries.

A number of people injured during the second world war harbour foreign bodies such as grenade splinters or bullets in some part of the body. Most of these metal fragments remain clinically silent. Some of them, however, may cause delayed complications. The purpose of this study was to determine the characteristics of delayed complications associated with foreign bodies after world war II injuries. 159 patients with retained foreign bodies after world war II injuries were retrospectively identified radiologically in our data bases in the time interval from 1997 to 2009. Diverse delayed complications secondary to the metal objects were diagnosed in 3 cases (2%): one patient with grenade splinter migration into the choledochal duct, one case with pseudotumoural tissue reaction, and one patient with late osteomyelitis. The time from injury to clinical presentation varied from 56 to 61 years. PubMed and Medline were screened for additional cases with delayed sequelae after foreign body acquisition during the 2nd world war. A 30 year search period from 1980 up to date was selected. 15 cases were identified here. Our study demonstrates that health consequences of the 2nd world war extend into the present time, and therefore physicians should be aware of the presence of hidden foreign bodies and their different possible late reactions.

Intramammary incidental findings on staging computer tomography.

PURPOSE: Incidental findings are a common feature in computer tomographic examinations of the chest. Breast incidentalomas, however, were described only sporadically. The purpose of this study was to evaluate retrospectively incidental breast findings and to compare radiological features of benign and malignant breast lesions. MATERIALS AND METHODS: From January 2006 to December 2010 a total of 8105 computer tomographic examinations were performed at our institution. In 89 patients incidental breast lesions were diagnosed. 64 of the identified patients were referred for further clinical, radiological, and hystopathological examination. All patients were female with a median age of 62 years, range 39-82 years. RESULTS: A total of 98 breast lesions were identified in the 64 patients. The mean size was 12.0±8.0 mm. Primary breast carcinoma was identified in 9, breast metastases in 27, and benign findings in 28 patients. Malignant lesions demonstrated more often marked enhancement and showed a higher density compared with benign lesions. Benign findings were more often lobular in shape and had spiculated margins. Most of the breast metastases were round or oval in shape with circumscribed margins and marked homogenous enhancement. There was no significant difference between the breast cancer and benign findings groups in the characteristics of the lesions. CONCLUSION: The breast is a very important region and should be carefully evaluate on chest CT. There are no certain radiological criteria to differentiate between malignant and benign breast lesions on CT. Therefore all breast incidentalomas should be evaluated by further radiological/histological investigations.

Primary breast sarcoma: prevalence, clinical signs, and radiological features.

BACKGROUND: Primary breast sarcoma is very rare. Most reports regarding sarcoma of the breast are clinical observations or pathological series and provide either no or inconstant radiological information. Radiological publications consist predominantly of isolated case reports or small series. PURPOSE: To determine the prevalence, clinical signs, and radiological features of primary breast sarcoma. MATERIAL AND METHODS: This is a retrospective review of 21 patients with breast sarcoma. All patients were female and their median age was 66 years (range 27-86). In all patients the diagnosis was confirmed histopathologically. RESULTS: The prevalence of breast sarcoma was 0.1% of all identified cases with breast malignancies. Clinically, all patients presented with solitary painless breast lumps. There was no uni- or bilateral axillary lymphadenopathy. On mammography (n = 19), two mammographic patterns could be identified: breast masses (68%), and architectural distortion (32%). On ultrasound (n = 8), most lesions were homogeneously hypoechoic, lobular or oval in shape with microlobulated or indistinct margins. On magnetic resonance imaging (n = 3), marked inhomogeneous contrast enhancement was seen in all investigated cases. CONCLUSION: The imaging findings of primary breast sarcoma are not pathognomonic. However, they should be taken into consideration in the differential diagnosis of breast lesions.

Metastases to the breast from non-mammary malignancies: primary tumors, prevalence, clinical signs, and radiological features.

RATIONALE AND OBJECTIVES: Most secondary intramammary tumors occur as metastatic involvement from the contralateral breast. Breast metastases (BM) from nonmammary malignancies are very rare. The aims of this study were to estimate retrospectively the prevalence of BM from nonmammary malignancies and to describe their radiologic appearance. MATERIALS AND METHODS: BM were identified in 51 patients, including 43 women and eight men with a median age of 61 years (range, 24-84 years). Computed tomography of the thoracic region identified 108 lesions in 38 patients. Mammography was available for 37 patients (54 lesions). Ultrasound evaluation was performed in 43 patients (71 lesions). In 24 patients (93 lesions), magnetic resonance imaging of the breast was done. Images were reviewed in consensus by two radiologists according to the Breast Imaging Reporting and Data System lexicon. RESULTS: The prevalence of BM in several tumors ranged from 0.12% to 4.92%. On computed tomography, most metastases were round or oval in shape with marked or moderate enhancement. On mammography, solitary or multiple round or oval masses with circumscribed margins were the most common pattern of BM. Ten percent showed microcalcifications. On ultrasound, most BM were hypoechoic, oval or round in shape, with microlobulated or circumscribed margins, and posterior acoustic enhancement. Doppler imaging showed hypervascularity in 39% of BM. On magnetic resonance imaging, most lesions demonstrated marked homogenous contrast enhancement. Type 1 kinetic curve was seen in 18%, type 2 in 52%, and type 3 in 30%. CONCLUSIONS: The radiologic features reported in this study should be taken into consideration in the differential diagnosis of breast lesions.