Incidental breast lesions detected on CT: what is their significance?

An increasing number of breast lesions are being detected incidentally on CT. The aim of this study was to investigate the rate of referrals to the breast unit for assessment of lesions identified on CT and the resulting yield of previously undiagnosed breast malignancies from this pathway. A retrospective review was undertaken of CT examinations conducted over a period of 14 years. All patients (with no previous history of breast cancer) whose report contained the keyword “breast” and who were referred to a specialist breast unit for assessment were reviewed. CT lesion morphology and enhancement pattern were identified and compared with the final diagnostic outcome. 70 patients were identified by retrospective analysis, yielding 78 incidental breast lesions, of which 22 (28.2%) were malignant (category B5). This gave a positive predictive value (PPV) for malignancy of 28.2%. The best morphological predictor of malignancy was spiculation (PPV, 76%) and irregularity (PPV, 58%), whereas calcification patterns (PPV, 36%) were diagnostically unhelpful. Malignant lesions were likely to be larger (mean, 28.5 mm) than benign lesions (mean, 20.2 mm; p<0.05). In conclusion, 30% of incidental breast lesions in this large series of patients proved to be unsuspected breast cancers, particularly irregular spiculated masses. Referral for formal triple assessment of CT-diagnosed breast lesions is worthwhile, and careful examination of the breast should be a routine part of CT examinations.Over the past 10 years, there has been an exponential rise in the use of CT imaging in all diagnostic areas [1]. Multidetector, single and dual source CT can give unprecedented spatial and temporal resolution [2, 3], identifying previously unseen structures and pathology and improving diagnostic accuracy. Greater utilisation and resolution of CT also results in an increased detection of “incidental” findings unrelated to the original diagnostic query, raising issues of further investigation, diagnosis and follow-up with consequent economic and emotional cost. It has long been known that CT can identify incidental breast lesions when imaging for cardiac or respiratory disease [4]. Previous review articles have described the appearances of incidental breast lesions found on CT [5–7], but there has been no formal quantitative assessment of the impact of incidental CT-diagnosed breast lesions. With implementation of the Department of Health Cancer Reform Strategies, including the age extension to the NHS Breast Screening Programme (NHSBSP) [8] and cancer pathway targets [9], the workload of breast assessment units is rising. The impact of referral of incidental breast lesions found on CT is therefore an important issue to consider, with respect to the accurate and timely diagnosis of breast malignancy.The aim of this study was to investigate the rate of referrals to the breast unit for assessment of lesions identified on CT and the resulting yield of previously undiagnosed breast malignancies from this pathway.     

Incidental adrenal lesions detected on enhanced abdominal dual-energy CT: Can the diagnostic workup be shortened by the implementation of virtual unenhanced images?

Objective

To determine whether post-processing of the data from portal-phase enhanced dual-energy CT (DECT), with or without the addition of a late enhanced phase acquisition, may enable characterization of adrenal lesions without the need for acquisition of pre-contrast images.

Materials and methods

Twenty-two patients with 24 adrenal lesions underwent unenhanced, venous and delayed phase DECT. Of these lesions, 20 were found to be adrenal adenomas, on the basis of histopathology, unenhanced attenuation values between 0 and −10 HU, or stability over at least 6 months.For all 24 lesions, true and virtual unenhanced attenuation values were measured based on the data of the portal (VNCp) and the delayed (VNCd) DECT acquisition. The absolute washout values based on the true non-contrast (TNC) and the VNCp and VNCd image series were also measured. The washout was also calculated based on the iodine concentration measured from both contrast-enhanced acquisitions.

Results

Mean virtual unenhanced attenuation values of all lesions calculated from the portal phase images was 12.6 HU, and was 4.02 HU higher than the values based on true unenhanced images (p = 0.020). Washout values calculated from virtual unenhanced attenuation based on the VNCp were also significantly different (p = 0.0304) while those calculated from VNCd and from iodine concentration correlated with the corresponding values based on the true unenhanced values (p > 0.999).

Conclusions

Our data indicate that attenuation values of adrenal adenomas based on virtual unenhanced images are significantly higher than those obtained with true unenhanced images. An incidental adrenal lesion with a virtual unenhanced attenuation lower than 10 HU can thus be safely characterized as an adenoma.     

Incidental Non-Cardiac Findings of a Coronary Angiography with a 128-Slice Multi-Detector CT Scanner: Should We Only Concentrate on the Heart?

Objective

To evaluate the spectrum, prevalence, and significance of incidental non-cardiac findings (INCF) in patients referred for a non-invasive coronary angiography using a 128-slice multi-detector CT (MDCT).

Materials and Methods

The study subjects included 1,044 patients; 774 males (mean age, 59.9 years) and 270 females (mean age, 63 years), referred for a coronary CT angiography on a 128-slice MDCT scanner. The scans were acquired from the level of the carina to just below the diaphragm. To evaluate INCFs, images were reconstructed with a large field of view (> 300 mm) covering the entire thorax. Images were reviewed in the axial, coronal, and sagittal planes, using the mediastinal, lung, and bone windows. The INCFs were classified as severe, indeterminate, and mild, based on their clinical importance, and as thoracic or abdominal based on their locations.

Results

Incidental non-cardiac findings were detected in 56% of patients (588 of 1,044), including 435 males (mean age, 65.6 years) and 153 females (mean age, 67.9 years). A total of 729 INCFs were observed: 459 (63%) mild (58% thoracic, 43% abdominal), 96 (13%) indeterminate (95% thoracic, 5% abdominal), and 174 (24%) severe (87% thoracic, 13% abdominal). The prevalence of severe INCFs was 15%. Two severe INCFs were histologically verified as lung cancers.

Conclusion

The 128-slice MDCT coronary angiography, in addition to cardiac imaging, can provide important information on the pathology of the chest and upper abdomen. The presence of severe INCFs is not rare, especially in the thorax. Therefore, all organs in the scan should be thoroughly evaluated in daily clinical practice.     

Clinical value of FDG PET/CT in the diagnosis of suspected recurrent ovarian cancer: is there an impact of FDG PET/CT on patient management?

Purpose  

The aim of this study was to evaluate the clinical value of FDG PET/CT in patients with suspected ovarian cancer recurrence as compared with diagnostic CT, and to assess the impact of the results of FDG PET/CT on treatment planning.     

Anterior temporal changes on MR images of children with hippocampal sclerosis: an effect of seizures on the immature brain?

BACKGROUND AND PURPOSE: Ipsilateral loss of anterior temporal gray-white matter definition, due mainly to white matter signal intensity abnormality, is frequently seen on MR images of patients with hippocampal sclerosis. Our aim was to determine the prevalence and clinical correlations of these anterior temporal changes in pediatric cases of hippocampal sclerosis and to determine whether cumulative damage from seizures is important for their development. METHODS: We reviewed the MR images and clinical details of 54 children (age range, 1.5-19 years) with typical hippocampal sclerosis. Specific imaging features noted included hippocampal sclerosis, anterior temporal changes, anterior temporal atrophy, and extra-hippocampal abnormality. RESULTS: Thirty-one (57%) of 54 children with hippocampal sclerosis had associated ipsilateral anterior temporal changes. Ipsilateral anterior temporal atrophy was associated with anterior temporal changes (P <.03). Children whose images showed anterior temporal changes were younger at onset of epilepsy (P <.01) and younger at antecedent cerebral insult (P <.03) than those with normal anterior temporal lobes. Most (84%) children whose images showed anterior temporal changes had experienced the onset of epilepsy or antecedent cerebral insult before the age of 2 years (P <.0009). Eighty-one percent of children with anterior temporal changes shown on their images experienced seizures at the time of antecedent insult. CONCLUSION: Ipsilateral anterior temporal changes identical to those observed in adult cases are seen on the MR images of young children with hippocampal sclerosis, with a similar prevalence, and are associated with either epilepsy onset or seizure-related cerebral insult before the age of 2 years. We suggest that the loss of gray-white matter definition may represent a persistent immature appearance, including an abnormality of myelin or myelination, possibly a result of seizures occurring during maturation of the temporal pole.     

Intravenous glucagon: does it optimize evaluation of the gastrointestinal tract on helical CT?

Forty outpatients were randomized into two groups of 20. Twenty patients received 1 mg of intravenous glucagon and the other 20 did not. Three radiologists evaluated the bowel using a qualitative score and mean scores for each bowel level were compared. A different radiologist measured the maximal diameter of bowel at seven levels. There were no significant differences in qualitative or quantitative data for the two groups. Intravenous glucagon is therefore not routinely recommended for helical CT of the abdomen.     

Multiplanar CT and MRI of collections in the retropharyngeal space: is it an abscess?

OBJECTIVE: The purpose of this article is to describe a practical imaging approach to evaluating collections in the retropharyngeal space. CONCLUSION: The differential diagnoses for fluid in the retropharyngeal space include both noninfectious and infectious processes. The multiplanar capabilities of CT and MRI are ideal for characterizing and delineating collections. In this pictorial essay, we describe the anatomy of the retropharyngeal space and offer a four-step approach to evaluating retropharyngeal collections on multiplanar imaging.     

Rapid osteolysis of the femoral neck: consequence of an insufficiency fracture of the hip?

Purpose

To describe the imaging and clinical features of rapid osteolysis of the femoral neck in an attempt to better understand this uncommon pathology.

Materials and methods

We retrospectively reviewed the files of 11 patients (six women and five men) aged 53–78 years diagnosed with rapid osteolysis of the femoral neck. Available imaging studies included radiographs, CT, MRI, and bone scintigraphy. Histopathological evaluations were available for seven cases.

Results

All patients presented with complaints of hip pain, six of whom had acute symptoms, while the rest had progressive symptoms and impairment. All but one case were found to have bone deposition in adjacent hip muscles. CT confirmed bone deposition in adjacent tissues and true osteolysis of the femoral neck with relative sparing of the articular surfaces. Bone scintigraphy and MRI were useful to exclude underlying neoplastic disease.

Conclusions

Rapid osteolysis of the femoral neck tends to occur in patients with underlying comorbidities leading to bone fragility and may actually represent a peculiar form of spontaneous insufficiency fracture. Recognition of its imaging features and clinical risk factors may help distinguish this process from other more concerning disorders such as infection or neoplasm.