Comparison of Early Contrast Enhancement Models in Ultrafast Dynamic Contrast-Enhanced Magnetic Resonance Imaging of Prostate Cancer.

Tofts models have failed to produce reliable quantitative markers for prostate cancer. We examined the differences between prostate zones and lesion PI-RADS categories and grade group (GG) using regions of interest drawn in tumor and normal-appearing tissue for a two-compartment uptake (2CU) model (including plasma volume (vp), plasma flow (Fp), permeability surface area product (PS), plasma mean transit time (MTTp), capillary transit time (Tc), extraction fraction (E), and transfer constant (Ktrans)) and exponential (amplitude (A), arrival time (t0), and enhancement rate (α)), sigmoidal (amplitude (A0), center time relative to arrival time (A1 - T0), and slope (A2)), and empirical mathematical models, and time to peak (TTP) parameters fitted to high temporal resolution (1.695 s) DCE-MRI data. In 25 patients with 35 PI-RADS category 3 or higher tumors, we found Fp and α differed between peripheral and transition zones. Parameters Fp, MTTp, Tc, E, α, A1 - T0, and A2 and TTP all showed associations with PI-RADS categories and with GG in the PZ when normal-appearing regions were included in the non-cancer GG. PS and Ktrans were not associated with any PI-RADS category or GG. This pilot study suggests early enhancement parameters derived from ultrafast DCE-MRI may become markers of prostate cancer.

Mammographic and sonographic features of tubular breast carcinoma.

AIMS AND BACKGROUND: This study aimed to describe the mammographic and sonographic features of tubular carcinoma of the breast. METHODS: A retrospective review of 198 consecutive cases of surgically proven breast cancer revealed ten cases of tubular carcinoma of the breast. Only tumors with a tubular component of at least 75% were included in the study. Mean patient age was 56 +/- 9 years, range 35 to 70 years. RESULTS: The mean size of the tumors was 11 +/- 4 mm. On mammography, all tubular carcinomas appeared as an irregularly shaped mass with a central density in 6/10 cases. Eight tubular carcinomas were described as having spiculated margins. Microcalcifications were present in 4/10 cases. On ultrasound the tumor presented as a hypoechoic mass with irregular margins and posterior acoustic shadowing in 7/10 cases. In three cases the tumor presented as a hypoechoic mass with ill-defined margins and posterior acoustic shadowing. CONCLUSIONS: Although some specific mammographic and sonographic features may suggest the presence of a tubular carcinoma, the final differential diagnosis from other spiculated lesions of the breast should rely on histologic evidence only. Therefore, surgical biopsy should be recommended in all cases of stellate lesions of the breast detected at mammography or ultrasonogram.

Dual-phase versus single-phase helical CT to detect and assess resectability of pancreatic carcinoma.

OBJECTIVE: The aim of this study was to compare dual-phase and single-phase helical CT for the detection and assessment of resectability of pancreatic adenocarcinoma. SUBJECTS AND METHODS: We studied 60 patients (31 men, 29 women; age range, 31-84 years; mean age, 62 years) with suspected pancreatic malignancy. Patients were randomly assigned to one of two groups. For group A (n = 30), unenhanced scans through the liver and pancreas were followed by two separate acquisitions (dual-phase) at 20-25 and at 60-80 sec after IV contrast administration. For group B (n = 30), unenhanced scans were followed by one set of scans (single-phase) acquired caudocranially (from the inferior hepatic margin to the diaphragm) starting 50 sec after IV contrast administration. Two observers independently scored images for the presence of tumor and for assessment of tumor resectability. RESULTS: Comparison of dual-phase versus single-phase helical CT for tumor detection showed a diagnostic accuracy for observer 1 of 87% and 90%, respectively, and for observer 2, of 90% and 87%, respectively. For both helical CT techniques, the overall agreement between the two observers was 83% (kappa = 0.73 +/- 0.03) for single-phase helical CT and 90% (kappa = 0.89 +/- 0.03) for dual-phase helical CT. The assessment of resectability was affected by the low number of resectable tumors (n = 8). CONCLUSION: Single-phase helical CT is effective for the diagnosis and assessment of resectability of patients with suspected pancreatic carcinoma. Advantages are the lower radiation dose and fewer images to film and store.