Incidental findings during follow-up scans in oncological patients.

BACKGROUND AND AIM: To assess the prevalence of incidental findings during follow-up scans of patients with oncologic pathology. METHODS: 499 follow-up scans from different patients with cancer pathology were retrospectively analyzed. Findings which were not suspected by the clinician or known from previous scans were considered as incidental lesions. We excluded lesions that were already suspected by the clinician or were already recorded in the patient's history before the initial computed tomography (CT) scan. The CT scans were performed on two different machines ("Siemens Somatom Sensation, 64 slices, Erlangen, Germany" and "Siemens Somatom Emotion, 16 slices, Erlangen, Germany").Most of the patients had a native scan followed by a thoraco-abdominal-pelvic image acquisition after the injection of intravenous contrast media. RESULTS: 28% of the patients had unsuspected incidental findings. The prevalence of incidental findings was similar: 56.6% of them were found in men and 43.4% in female patients. In 6 cases (1.2%) the presence of unsuspected pulmonary embolism was discovered. From these cases, 5 (83.3%) had metastatic disease at the moment of the follow-up CT scan and 1 (16.6%) had metastasis-free disease. In 17 patients out of 499 (3.4%) we incidentally made an important discovery which either changed the cancer therapy or required immediate treatment. CONCLUSION: Incidental findings are not rare in oncological patients and the radiologist has to be aware of their presence in order not to overlook them and to correctly diagnose them.

The role of the diffusion sequence in magnetic resonance imaging for the differential diagnosis between hepatocellular carcinoma and benign liver lesions.

BACKGROUND AND AIM: To assess the role of diffusion weighted imaging sequence (DWI), routinely used in hepatic magnetic resonance imaging (MRI) for the differentiation of hepatocellular carcinoma (HCC) from benign liver lesions. METHODS: A number of 56 liver MRI examinations were retrospectively analyzed independently by two experienced radiologists, blinded to each other results. A total number of 70 Focal Liver Lesions (FLLs) assessed by liver MRI in 56 patients were included in the present study. All lesions were retrospectively analyzed by two experienced radiologists, independently from each other and who were not aware of the previous results given by using different imaging techniques. All included FLLs had a final histological diagnosis, or the final diagnosis was based on consensus reading by two experienced radiologists. The signal of the included FLLs was qualitatively appreciated on the b-800 sequences and on the apparent diffusion coefficient (ADC) map. The ADC value of each FLL was measured and the ADC ratio between the ADC value of the assessed FLL and that of the surrounding liver parenchyma was calculated. RESULTS: The mean ADC value for benign FLLs as assessed by the two independent readers was 1.75 × 10(-3) and 1.72 × 10(-3). The mean ADC value for HCC nodules was 0.92 × 10(-3) for the first reader and 0.91 × 10(-3) for the second reader respectively. The mean ADC ratio for benign FLLs was 1.81 and 1.84 for the two readers, respectively. The ADC ratio for HCC nodules was 0.91 and 0.91, respectively. The ADC value is an indicator which is less prone to interobserver variability (correlation of 0.919→1). The ADC ratio has, as the analysis of the ROC curve shows, the best predictive value for differentiation between benign FLLs and HCC nodules. Analysis of the signal intensity on the DWI b-800 image alone is of no significance in differentiating benign FLLs from HCC nodules (p>0.005). CONCLUSIONS: The ADC value and the ADC ratio assessed on liver DWI are useful diagnostic tools in the differential diagnosis of benign FLLs vs HCC nodules. Quantitative methods such as calculating the ADC value or ADC ratio have better diagnostic value than qualitative techniques.

Ultrasound in the diagnosis of papillary breast lesions.

Papillary lesions are defined as an amalgam of various lesions which represent a diagnostic challenge, for both the radiologist and pathologist. They are diagnosed on the basis of a combination of clinical, imaging, and pathological findings and their features carry differing prognostic implications for the affected patients. The aim of this pictorial essay is to review the clinical and pathological findings in papillary breast lesions, to show the advantages and limits of each imaging method in their diagnosis with emphasis on the importance of ultrasound in the differential diagnosis. Also, the spectrum of ultrasound features (conventional, Doppler ultrasound and elastography) of papillary lesions of the breast will be illustrated.

Diffusion Weighted Magnetic Resonance Imaging for the Classification of Focal Liver Lesions as Benign or Malignant.

BACKGROUND AND AIMS: To assess the role of diffusion weighted imaging sequence (DWI), routinely used in hepatic magnetic resonance imaging (MRI) for the differentiation of focal liver lesions (FLLs) as benign or malignant. METHOD: 99 FLLs assessed by liver MRI in 80 patients were included in the present study. All lesions were retrospectively analyzed by two experienced radiologists, independent from each other, who were not aware of the previous results obtained by using different imaging techniques. All included FLLs had a final histological diagnosis or a final diagnosis based on consensus reading by two experienced radiologists and follow-up at 6 months. The FLLs signal was qualitatively appreciated on the b-800 sequences and on the apparent diffusion coefficient (ADC) map. The ADC value of each FLL was measured and the ADC ratio between the ADC value of the assessed FLL and that of the surrounding liver parenchyma were calculated. RESULTS: The mean ADC value for benign FLLs as assessed by the two independent readers was 1.78 x 10¯³ and 1.72 x 10¯³, respectively. The mean ADC value for malignant FLLs was 0.92 x 10¯³ for the first reader and 0.95 x 10¯³ for the second reader. The mean ADC ratio for benign FLLs was 1.91 and 1.85 for the two readers and for malignant FLLs was 0.91 and 0.94, respectively. Using an ADC value lower than 1.024 x 10¯³ offers a specificity of 100% and a sensitivity of 62.5% for the diagnosis of malignant FLLs. The ADC value is an indicator which is less prone to interobserver variability (correlation of 0.919→1). The ADC ratio has, as the analysis of the ROC curve shows, the best predictive value for differentiation between benign and malignant FLLs. Analysis of the signal intensity on the DWI b-800 image alone is of no significance in differentiating benign from malignant FLLs (p>0.05). CONCLUSIONS: The ADC value and the ADC ratio assessed on liver DWI are useful diagnostic tools in the differential diagnosis of benign vs. malignant FLLs. Quantitative methods such as calculating the ADC value or ADC ratio have better diagnostic value than the qualitative techniques.