Tracer kinetics analysis of dynamic contrast-enhanced CT and MR data in patients with squamous cell carcinoma of the upper aerodigestive tract: comparison of the results

Contrast-enhanced ultrasonography of cervical carcinoma: perfusion pattern and relationship with tumour angiogenesis

OBJECTIVE

This study aimed to investigate the use of contrast-enhanced ultrasonography (CEUS) and time-intensity curves to assess angiogenesis in cervical cancer.

METHODS

60 patients who were scheduled to undergo radical surgery for biopsy-proven cervical cancers underwent CEUS. Surgical tissue sections from 32 patients who did not receive neoadjuvant chemotherapy were analyzed with CD34 staining to estimate intratumoral microvessel density (MVD). CEUS images were analyzed for maximum intensity (IMAX), rise time (RT), time to peak (TTP) and mean transit time.

RESULTS

Cervical lesions had a higher IMAX and shorter RT and TTP (p < 0.001) than reference regions. There was a linear association between the IMAX of the cervical lesion and the mean intratumoral MVD (r = 0.624, p < 0.001). There were no significant differences in CEUS variables according to histological type, grade and stage.

CONCLUSION

Quantitative CEUS variables have potential use for monitoring perfusion changes in tumours after non-surgical therapy for advanced cervical cancer.

ADVANCES IN KNOWLEDGE

The article demonstrates the capability and value of quantitative CEUS as a non-invasive strategy for detecting the perfusion and angiogenic status of cervical cancer. Quantitative CEUS variables have potential use for monitoring tumour response to non-surgical therapy.

Contrast-enhanced perfusion magnetic resonance imaging for head and neck squamous cell carcinoma: a systematic review

This systematic review gives an extensive overview of the current state of perfusion-weighted magnetic resonance imaging (MRI) for head and neck squamous cell carcinoma (HNSCC). Pubmed and Embase were searched for literature until July 2014 assessing the diagnostic and prognostic performance of perfusion-weighted MRI in HNSCC. Twenty-one diagnostic and 12 prognostic studies were included for qualitative analysis. Four studies used a T2(∗) sequence for dynamic susceptibility (DSC)-MRI, 29 studies used T1-based sequences for dynamic contrast enhanced (DCE)-MRI. Included studies suffered from a great deal of heterogeneity in study methods showing a wide range of diagnostic and prognostic performance. Therefore we could not perform any useful meta-analysis. Perfusion-weighted MRI shows potential in some aspects of diagnosing HNSCC and predicting prognosis. Three studies reported significant correlations between hypoxia and tumor heterogeneity in perfusion parameters (absolute correlation coefficient |ρ|>0.6, P<0.05). Two studies reported synergy between perfusion-weighted MRI and positron emission tomography (PET) parameters. Four studies showed a promising role for response prediction early after the start of chemoradiotherapy. In two studies perfusion-weighted MRI was useful in the detection of residual disease. However more research with uniform study and analysis protocols with larger sample sizes is needed before perfusion-weighted MRI can be used in clinical practice.

Functional imaging of the liver

Anatomical-based imaging is used widely for the evaluation of diffuse and focal liver, including detection, characterization, and therapy response assessment. However, a limitation of anatomical-based imaging is that structural changes may occur relatively late in a disease process. By applying conventional anatomical-imaging methods in a more functional manner, specific pathophysiologic alterations of the liver may be assessed and quantified. There has been an increasing interest in both the clinical and research settings, with the expectation that functional-imaging techniques may help solve common diagnostic dilemmas that conventional imaging alone cannot. This review considers the most common functional magnetic resonance imaging, computed tomography, and ultrasound imaging techniques that may be applied to the liver.

A comparison of dynamic contrast-enhanced CT and MR imaging-derived measurements in patients with cervical cancer

This work is to compare the kinetic parameters derived from the DCE-CT and -MR data of a group of 37 patients with cervical cancer. The modified Tofts model and the reference tissue method were applied to estimate kinetic parameters. In the MR kinetic analyses using the modified Tofts model for each patient data set, both the arterial input function (AIF) measured from DCE-MR images and a population-averaged AIF from the literature were applied to the analyses, while the measured AIF was used for the CT kinetic analysis. The kinetic parameters obtained from both modalities were compared. Significant moderate correlations were found in modified Tofts parameters [volume transfer constant(K(trans) ) and rate constant (k(ep) )] between CT and MR analysis for MR with the measured AIFs (R = 0·45, P<0·01 and R = 0·40, P<0·01 in high-K(trans) region; R = 0·38, P<0·01 and R = 0·80, P<0·01 in low-K(trans) region) as well as with the population-averaged AIF (R = 0·59, P<0·01 and R = 0·62, P<0·01 in high-K(trans) region; R = 0·50, P<0·01 and R = 0·63, P<0·01 in low-K(trans) region), respectively. In addition, from the Bland-Altman plot analysis, it was found that the systematic biases (the mean difference) between the modalities were drastically reduced in magnitude by adopting the population-averaged AIF for the MR analysis instead of the measured ones (from 51·5% to 18·9% for K(trans) and from 21·7% to 4·1% for k(ep) in high-K(trans) region; from 73·0% to 29·4% for K(trans) and from 63·4% to 24·5% for k(ep) in low-K(trans) region). The preliminary results showed the feasibility in the interchangeable use of the two imaging modalities in assessing cervical cancers.