Shear Wave Dispersion Imaging for the Characterization of Focal Liver Lesions - A Pilot study.

PURPOSE: Shear wave dispersion imaging is a novel ultrasound-based technique, which analyzes the speed of different shear wave components depending on their frequency. The dispersion of shear wave speed correlates with the viscosity of the liver parenchyma. The aim of this prospective study was to evaluate the use of shear wave dispersion imaging in focal liver lesions in the non-cirrhotic liver. METHODS: Patients with unclear focal liver lesions in B-mode ultrasound were prospectively assigned to shear wave dispersion imaging (m/s/kHz). Measurements were conducted within the lesion and in the liver parenchyma of the right liver lobe using an intercostal window. Histology and contrast-enhanced ultrasound served as the reference for the characterization of the lesions. RESULTS: Out of 46 patients included in this study, 24 had liver metastases and 22 had benign liver lesions. Benign lesions consisted mostly of hemangiomas (n=12) and focal nodular hyperplasia (n=8). Malignant lesions showed significantly lower shear wave dispersion (13.0±2.45 m/s/kHz) compared to benign tumors (15.2±2.74 m/s/kHz, p<0.01). In further subgroup analysis, the difference was significant for hemangiomas (15.32±2.42 m/s/kHz, p=0.04) but not for FNHs (14.98±3.36 m/s/kHz, p=0.38). The dispersion of reference liver parenchyma did not differ significantly between the groups (p=0.54). CONCLUSION: The quantification of viscosity by shear wave dispersion is a new parameter for the characterization of focal liver lesions with higher dispersion values in hemangiomas and lower dispersion values in metastases. However, it cannot differentiate reliably between benign and malignant lesions.

[Follicle centre lymphoma: treatment results for stage I and II]. / Behandlungsergebnisse beim follikulären Keimzentrumslymphom Stadium I und II.

PURPOSE: Radiotherapy is a curative treatment modality in the early stages of follicle centre lymphoma. Survival rates, patterns of failure and prognostic factors were evaluated in a retrospective analysis. PATIENTS AND METHODS: 116 patients with follicle centre lymphoma stage I and II were treated between 1970 and 1999 in Dresden. Therapy modalities were radiotherapy alone (103 patients) or combined radiotherapy/chemotherapy (13 patients). Radiotherapy was applied as involved-field-(IFI)- (104 patients), extended-field- (nine patients) or total-nodal- (three patients) irradiation. Patients received doses between 25 Gy and 50 Gy (median 35 Gy). RESULTS: The 5- and 10-year actuarial overall survival rates were 76% and 51%. Relapse free survival was 62% and 48% respectively. The median follow-up was 4,0 years. Relapses after complete remission were registered in 44 cases. Six patients have had in-field-recurrences. The majority of out-field-recurrences were nodal relapses (50%). 11% of relapses occurred outside of lymph nodes or were disseminated failures (18%). Significant favorable prognostic factors identified by multivariate and univariate analysis were low age (age < 50 years vs. age > 50 years), low stage and performance of bipedal lymphangiography as primary staging procedure. CONCLUSIONS: Radiotherapy is an effective and tolerable treatment modality for follicle centre lymphoma in the early stages I and II. We registered a high proportion of nodal recurrences, which may be minimized by prophylactic extended radiotherapy.