Liver volume variations as a parameter to assess therapy response in advanced metastatic liver disease.

BACKGROUND: The aim of this study was to evaluate liver volume variations (LVV) as a parameter to assess the therapy response in patients with advanced liver metastasis (aLM). METHODS: Patients with colorectal cancer and consecutive computed tomography (CT) scans were divided into a group with aLM receiving palliative chemotherapy (n = 24) and a control group (n = 21) being followed after curative therapy. Liver volumetry was performed manually. The therapy response was assessed according to the response evaluation criteria in solid tumors (RECIST, n = 69). LVV were compared between groups and to variations in the sum-of-longest-diameter (SLDV). Using receiver operating characteristic (ROC) analysis, LVV were evaluated for distinguishing between progressive disease (PD) and stable disease (SD)/partial remission (PR). RESULTS: Median LVV between patients with aLM (10.0%) and the control group (4.0%) differed significantly (p < 0.01). PD led to a larger median LVV (26.8%) than PR/SD (5.0%, p < 0.01). LVV in aLM patients correlated positively with SLDV (r = 0.71, p < 0.01). A cut-off value of 9.5% allowed distinguishing between PD and SD/PR (sensitivity: 86%, specificity: 88%, p < 0.01). CONCLUSION: LVV are helpful to assess PD in patients with aLM.

Consensus report on the radiological management of patients with gastrointestinal stromal tumours (GIST): recommendations of the German GIST Imaging Working Group.

The aim was to reach consensus in imaging for staging and follow-up as well as for therapy response assessment in patients with gastrointestinal stromal tumours (GIST). The German GIST Imaging Working Group was formed by 9 radiologists engaged in assessing patients with GIST treated with targeted therapy. The following topics were discussed: indication and optimal acquisition techniques of computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET)/CT; tumour response assessment considering response criteria and measurement techniques on CT, MRI and PET/CT; result interpretation; staging interval and pitfalls. Contrast-enhanced CT is the standard method for GIST imaging. MRI is the method of choice in case of liver-specific questions or contraindications to CT. PET/CT should be used for early response assessment or inconclusive results on morphologic imaging. All imaging techniques should be standardized allowing a reliable response assessment. Response has to be assessed with respect to lesion size, lesion density and appearance of new lesions. A critical issue is pseudoprogression due to myxoid degeneration or intratumoural haemorrhage. The management of patients with GIST receiving a targeted therapy requires a standardized algorithm for imaging and an appropriate response assessment with respect to changes in lesion size and density.

Diagnostic yield of computed tomography-guided coaxial core biopsy of undetermined masses in the free retroperitoneal space: single-center experience.

The purpose of this study was to evaluate the diagnostic yield of core biopsy in coaxial technique under guidance of computed tomography (CT) for retroperitoneal masses. We performed a retrospective analysis of CT-guided coaxial core biopsies of undetermined masses in the non-organ-bound retroperitoneal space in 49 patients. In 37 cases a 15-G guidance needle with a 16-G semiautomated core biopsy system, and in 12 cases a 16-G guidance needle with an 18-G biopsy system, was used. All biopsies were technically successful. A small hematoma was seen in one case, but no relevant complication occurred. With the coaxial technique, up to 4 specimens were obtained from each lesion (mean, 2.8). Diagnostic accuracy in differentiation between malignant and benign diseases was 95.9%. A specific histological diagnosis could be established in 39 of 42 malignant lesions (92.9%). Correct subtyping of malignant lymphoma according to the WHO classification was possible in 87.0%. Benign lesions were correctly identified in seven cases, although a specific diagnosis could only be made in conjunction with clinical and radiological information. In conclusion, CT-guided coaxial core biopsy provides safe and accurate diagnosis of retroperitoneal masses. A specific histological diagnosis, which is essential for choosing the appropriate therapy, could be established in most cases of malignancy.