Quantitative diagnosis of carotid blowout syndrome with CT perfusion: Carotid blowout syndrome CTP quantitative diagnosis

BACKGROUND AND PURPOSE

Carotid blowout syndrome (CBS) is a potentially fatal disease. The CBS diagnosis mainly relies on subjective observations and the quantitative diagnotic method was not well established. This study aimed to diagnose CBS severity by computed tomography perfusion (CTP) parameters with different region-of-interest (ROI) models.

MATERIALS AND METHOD

We prospectively recruited CBS patients between February 1, 2018 and July 31, 2023 in a tertiary medical center, and CTP was performed using the same 128-detector CT machine. Digital subtraction angiography (DSA) and elective endovascular intervention were performed within 3 days post-CTP for diagnosis confirmation and treatments. CBS severity was classified into ongoing (threatened + impending) or acute CBS based on DSA findings and clinical features. Pericarotid soft-tissue (PCST) CTP parameters, including blood flow (BF), blood volume (BV), mean transit time (MTT) and flow extraction product (FEP), were evaluated and correlated on DSA. We depicted models A, B and C for the small focal lesion in 1 cm of PCST, 1 cm around PCST and the whole PCST respectively.

RESULTS

CTP images of 110 patients (77 ongoing (45 threatened + 32 impending); 33 acute) were analyzed. Pericarotid BV (1.8 ± 1.2vs.3.5 ± 2.0; p < 0.001) in Model A and BF in Model B (42.6 ± 11.0vs.50.9 ± 20.4; p = 0.031) were lower in acute-CBS than in ongoing-CBS patients. Subgroup analysis demonstrated lower BV in acute (1.8 ± 1.2) compared with threatened (3.7 ± 2.3; p < 0.001; p < 0.001) and impending (3.2 ± 1.6; p = 0.009) CBS patients in Model A.

CONCLUSION

CBS severity can be quantitatively diagnosed by pericarotid soft-tissue CTP parameters. In Model A (small focus), BV was capable of differentiating acute CBS from other subtypes, demonstrating its potential role as a CBS imaging biomarker.

Pseudocontinuous Arterial Spin Labeling: Clinical Applications and Usefulness in Head and Neck Entities

Simple Summary

Conventional imaging methods, such as ultrasonography, computed tomography, and magnetic resonance imaging may be inadequate to accurately diagnose lesions of the head and neck because they vary widely. Recently, the arterial spin labeling technique, especially pseudocontinuous arterial spin labeling (pCASL) with the three-dimensional (3D) readout method, has been dramatically developed to improve diagnostic performance for lesion differentiation, which can show prominent blood flow characteristics. Here, we demonstrate the clinical usefulness of 3D pCASL for diagnosing various entities, including inflammatory lesions, hypervascular lesions, and neoplasms in the head and neck, for evaluating squamous cell carcinoma (SCC) treatment responses, and for predicting SCC prognosis.

Abstract

As functional magnetic resonance imaging, arterial spin labeling (ASL) techniques have been developed to provide quantitative tissue blood flow measurements, which can improve the performance of lesion diagnosis. ASL does not require contrast agents, thus, it can be applied to a variety of patients regardless of renal impairments and contrast agent allergic reactions. The clinical implementation of head and neck lesions is limited, although, in recent years, ASL has been increasingly utilized in brain lesions. Here, we review the development of the ASL techniques, including pseudocontinuous ASL (pCASL). We compare readout methods between three-dimensional (3D) turbo spin-echo and 2D echo planar pCASL for the clinical applications of pCASL to head and neck lesions. We demonstrate the clinical usefulness of 3D pCASL for diagnosing various entities, including inflammatory lesions, hypervascular lesions, and neoplasms; for evaluating squamous cell carcinoma (SCC) treatment responses, and for predicting SCC prognosis.

Multidetector Computed Tomography Perfusion in Head and Neck Squamous Cell Carcinomas: Evaluation of a Dose Reduction Strategy

Background Computed tomography perfusion (CTp), a useful technique in oncology, is not widely utilized due to the high radiation dose delivered from it. It involves scanning the region of interest every second for 50 seconds following intravenous contrast administration. Doubling sampling interval (SI) to 2 seconds will half the radiation dose, but may impact its effectiveness, which needs to be evaluated.

Objectives To evaluate a dose reduction strategy in CTp by determining agreement between standard dose (SD) CTp (acquisition with SI 1 second) and low-dose CTp techniques with SI of 2 seconds (achieved either by reconstruction only or true low-dose acquisition).

Materials and methods This cross-sectional study was conducted on histopathology-proven head and neck squamous cell carcinoma (HNSCC) patients who underwent CTp on 64 slice multidetector CT. A total of 56 patients had SD and 24 patients underwent true low dose (LD) acquisition. SD data were also reconstructed at SI 2 seconds to obtain a dataset simulating low dose (low-dose reconstruction [LDr]). Paired t-test was applied to compare CTp in SD and LDr groups and the Bland–Altman plot drawn to calculate 95% confidence limit of agreement. The Kolmogorov–Smirnov test compared CTp parameters for LDr and LD groups.

Results There was no statistical difference in CTp parameters (except blood flow in malignant) in SD and LDr groups for both malignant and normal tissues. CTp of malignant tissue was not statistically different in LDr and LD groups but the radiation dose was half in the LD group.

Conclusion Reduction of radiation dose to half achieved by doubling the SI does not affect the CTp parameters significantly. So LD acquisitions will increase the use of CTp in HNSCC.

Perfusion Computed Tomography Scan Imaging in Differentiation of Benign from Malignant Parotid Lesions

Introduction  The most common site of salivary gland tumors is the parotid gland. Computed tomography (CT), magnetic resonance imaging (MRI), and sonography are imaging modalities to differentiate benign from malignant parotid tumors.

Objective  The aim of this study is the evaluation of the diagnostic value of perfusion CT for differentiating histological categorization of benign and malignant parotid tumors.

Methods  A total of 29 patients with parotid neoplasms were enrolled in this study. Mean age and all CT perfusion variables (gradient and permeability, blood flow [BF], blood volume [BV], mean transit time [MTT], permeability surface [PS], maximum intensity projection [MIP], time-density curve [TDC], and time to peak [TTP]) were compared among three groups (malignant tumors [MTs], Warthin's tumor [WT] and pleomorphic adenomas [PA]).

Results  The mean age of the patients was 55.9 ± 14.1 (26–77), and 15 of them were male (51.7%). Eleven lesions were PAs [37.9%], 8 lesions were WTs (27.6%0 and 10 lesions (34.5%) were MTs (6 acinic cell carcinomas [ACCs], 3 adenocystic carcinomas [AdCCs], and 1 mucoepidermoid carcinoma [MEC]). The mean age of the patients with WTs was 62 ± 7.5 years; 52 ± 14.2 for patients with Pas, and 55.2 ± 17.2 for those with MTs ( p  = 0.32). The mean MIP was 122.7 ± 12.2 in WT, while it was 80.5 ± 19.5 in PA, and 76.2 ± 27.1 in MTs ( p  < 0.001); The mean MIP for WT was higher than for PAs and MTs; the values of MTs and PAs were not statistically different. The average of BF, BV, and curve peak were higher in WTs in comparison with the other two groups, and curve time 2 and TTP were higher in PAs in comparison with MTs.

Conclusion  Based on this study, perfusion CT of the parotid gland and its parameters can distinguish between benign and malignant parotid masses.

Imaging biomarkers in upper gastrointestinal cancers

In parallel with the increasingly widespread availability of high performance imaging platforms and recent progresses in pathobiological characterisation and treatment of gastrointestinal malignancies, imaging biomarkers have become a major research topic due to their potential to provide additional quantitative information to conventional imaging modalities that can improve accuracy at staging and follow-up, predict outcome, and guide treatment planning in an individualised manner. The aim of this review is to briefly examine the status of current knowledge about imaging biomarkers in the field of upper gastrointestinal cancers, highlighting their potential applications and future perspectives in patient management from diagnosis onwards.

Is computed tomography perfusion a useful method for distinguishing between benign and malignant neck masses?

Evaluation of neck masses is frequent in ear, nose, and throat clinics. Successful outcomes associated with neck mass are directly related to rapid diagnosis and accurate treatment for each patient. Late diagnosis of a malignant mass increases the magnitude of morbidity and the rate of mortality of the disease. Although magnetic resonance imaging and computed tomography (CT) examinations are important tools for evaluating head and neck pathologies, they do not allow functional evaluation. For this reason, CT perfusion (CTP) as a method of functional evaluation for distinguishing benign from malignant masses is gaining attention. The utility of CTP for distinguishing between benign and malignant mass lesions was investigated in 35 patients with masses in the neck (11 benign, 24 malignant). CTP was shown to be a useful method for identifying head and neck tumors and blood volume values to enable the differential diagnosis of benign and malignant head and neck tumors.

Detection of cartilage invasion in laryngeal carcinoma with dynamic contrast-enhanced CT

Objective

Staging of laryngeal cancer largely depends on cartilage invasion. Presence of cartilage invasion affects treatment choice and prognosis. On MRI and contrast‐enhanced CT (CECT) it may be challenging to differentiate cartilage invasion from inflammation. The purpose of this study is to compare the diagnostic properties of dynamic contrast‐enhanced CT (DCECT) and CECT for visual detection of cartilage invasion in laryngeal cancer.

Study Design

Prospective cohort study.

Methods

Patients with T3 or T4 laryngeal squamous cell carcinoma treated with total laryngectomy were evaluated using 0.625 mm slice CT. DCECT derived permeability and blood volume maps and CECT images were visually evaluated for the presence of invasion of the cartilaginous T‐stage subsites of laryngeal cancer, by detecting continuity with the tumor‐bulk of increased permeability, increased blood volume, and enhancement. Histological evaluation of the surgical total laryngectomy specimen served as the gold standard. Sensitivity, specificity, negative predictive value, and positive predictive value were calculated and compared using the McNemar and Chi‐squared test.

Results

From 14 included patients, a total of 462 subsites were available for T‐stage analysis, of which 84 were cartilage. The median time between CT imaging and total laryngectomy was 1 day (range 1–34 days). There was no significant difference in the detection of cartilage invasion between DCECT and CECT. The sensitivity of CECT was better for all subsites combined (0.85 vs. 0.75; p < 0.01).

Conclusion

DCECT does not improve visual detection of cartilage invasion in T3 and T4 laryngeal cancer compared to CECT.

Level of Evidence

2b, individual cohort study.

Role of perfusion CT in the evaluation of functional primary tumour response after radiochemotherapy in head and neck cancer: preliminary findings

OBJECTIVE

To report the initial results of a prospective study aimed at evaluating the CT perfusion parameter changes (∆PCTp) of the primary tumour after radiochemotherapy (RCT) in head and neck cancer (HNC) and to correlate with positron emission tomography (PET)/CT response.

METHODS

Eligibility criteria included HNC (Stage III-IV) candidates for RCT. Patients underwent perfusion CT (PCT) at baseline and at 3 weeks and 3 months after treatment. Blood volume, blood flow, mean transit time (MTT) and permeability surface (PS) product were computed. Moreover, PET/CT was performed at baseline and 3 months after treatment. The ∆PCTp were evaluated between baseline and 3-week/3-month evaluations, whereas PET/CT response was based on the maximum standardized uptake value changes according to the European Organization for Research and Treatment of Cancer criteria.

RESULTS

Between July 2012 and July 2015, 25 patients were enrolled. A significant reduction of all CT tumour perfusion parameters (PCTp) was observed from the baseline to after RCT (p < 0.001). Specifically, a significant reduction was shown at 3 weeks for all PCTp except MTT (from 6.18 to 5.14 s; p = 0.722). Differently, a significant reduction of all PCTp (p < 0.001) including MTT (from 6.18 to 2.24 s; p = 0.001) was shown at 3 months. Moreover, the reduction of PS resulted in a significant prediction of PET/CT response at 3 months (p = 0.037) with the trend also at 3 weeks (p = 0.099) at the multivariate analysis.

CONCLUSION

Our preliminary findings seem to show that almost all PCTp are significantly reduced after RCT, whereas PS seems to come out as the strongest factor in predicting the PET/CT response.

ADVANCES IN KNOWLEDGE

This article provides information on the potential useful role of PCT in evaluating tumour response after both early and late RCT.

Computed Tomography Perfusion of Prostate Cancer: Diagnostic Value of Quantitative Analysis

OBJECTIVE

The aim of the study was to assess the diagnostic value of computed tomography perfusion (CTp) of prostate in distinguishing between normal tissue and malignant lesion by using quantitative threshold values of CTp parameters.

MATERIALS AND METHODS

Sixty-one consecutive men with indication for radical prostatectomy were prospectively enrolled. All patients were intravenously injected with 80-mL bolus of nonionic iodinated contrast medium during cine-mode acquisition protocol. Perfusion data sets were analyzed by a dedicated software system and values for each of the 4 CTp parameters (blood volume, blood flow, mean transit time, and permeability surface-area product measurements) were recorded. Receiver operating characteristic curves were calculated to find which CTp parameter and which cutoff value might reveal the best diagnostic accuracy. Histopathology was used as reference standard.

RESULTS

Statistical correlation between radiological and pathological results was performed on 48 patients using 3456 segmented squares. Blood volume and permeability surface revealed the best diagnostic accuracy for differentiating between malignant and benign squares, with cutoff values of 6.1 and 16.5, respectively, and a sensitivity of 84.8% and 81.8%, respectively. All parameters showed also a high negative predictive value: 97.1% for blood volume and 95.4% for permeability surface.

CONCLUSIONS

Blood volume and permeability surface are the 2 CTp parameters with the highest diagnostic accuracy in differentiating between normal tissue and prostatic neoplasia. Due to the extremely high negative predictive value, they are particularly valuable in excluding the presence of cancer and thus resulting potentially useful in assessing cancer response to adjuvant therapy.

Usefulness of Pseudocontinuous Arterial Spin-Labeling for the Assessment of Patients with Head and Neck Squamous Cell Carcinoma by Measuring Tumor Blood Flow in the Pretreatment and Early Treatment Period

BACKGROUND AND PURPOSE

For the assessment of the treatment response in non-surgical treatment, tumor blood flow provides the functional information of the tumor which is different from the morphological information such as tumor volume. The purpose of this study was to evaluate the diagnostic value of tumor blood flow values obtained by pseudocontinuous arterial spin-labeling in patients with head and neck squamous cell carcinoma.

MATERIALS AND METHODS

Forty-one patients with head and neck squamous cell carcinoma were evaluated by using pseudocontinuous arterial spin-labeling. Quantitative tumor blood flow was calculated at the pretreatment and the early treatment periods in all the patients, and the percentage change of tumor blood flow between the two was calculated. At the early treatment period, based on their tumor volume reduction rate, we divided the patients into stable disease and partial response groups for a subgroup analysis. The local control or failure was confirmed either by histopathology or by radiologic evaluation within the follow-up.

RESULTS

Pretreatment tumor blood flow in patients in the failure group was significantly lower than that in patients in the local control group. In the subgroup analysis of patients with stable disease, the percentage change of tumor blood flow was significantly larger (due to the tumor blood flow increase from pretreatment value) in the local control group than in the failure group. In addition, in patients with a partial response, the percentage change of tumor blood flow was significantly smaller (due to the tumor blood flow decrease from the pretreatment value) in the local control group than in the failure group. The accuracy for determination of the local control group or the failure group in pretreatment tumor blood flow was 0.83 and that in the combination use of the percentage change of tumor blood flow and tumor volume in the early treatment period was 0.93.

CONCLUSIONS

Tumor blood flow obtained by pseudocontinuous arterial spin-labeling can be useful for the determination of local control. The combined use of the percentage change of tumor blood flow and tumor volume had particularly high diagnostic accuracy.

Volumetric CT perfusion assessment of treatment response in head and neck squamous cell carcinoma: Comparison of CT perfusion parameters before and after chemoradiation therapy

Background and purpose

World Health Organization estimated that there were 600,000 new cases of head and neck cancers and 300,000 deaths each year worldwide. Scientific modalities to predict the treatment outcomes are not available yet. We conducted this study to (1) compare CT perfusion parameters before and after chemoradiation among patients with head and neck squamous cell carcinoma and (2) to evaluate the prognostic value of each perfusion parameter in predicting the response to chemoradiation.

Materials and methods

We conducted a prospective study among all patients with head and neck squamous cell carcinoma registered for chemoradiotherapy (CRT) at Regional Cancer Research Center, Shimla, Himachal Pradesh, India during the period June 2012 through June 2013. CTp data were acquired on a 64-slice CT scanner (Light speed VCT Xte; GE Healthcare) with 14 cm z-axis coverage using Volume Helical Shuttle (VHS) feature at baseline, on completion of 40 Gy and 66 Gy of chemoradiation. We dichotomised the treatment outcome as complete response and non-response (partial responders/stable disease/progressive disease) using RECIST 1.1 criteria. We compared all perfusion parameters at baseline, 40 Gy and 66 Gy of CRT between responders and non-responders. We dichotomised the perfusion parameters as high (>median value) and low (≤median value) to analyze association between perfusion parameters and treatment outcome. We calculated the sensitivity, specificity, predictive values, and likelihood ratios for each dichotomized perfusion parameter using Wilson Score method.

Results

We followed 24 patients (23 of them men) from start of the treatment till completion of it. All had Stage III or Stage IV of the disease. Blood flow (BF) and blood volume (BV) decreased and Mean Transit Time (MTT) increased significantly (p < 0.05) at 66 Gy among responders to CRT as compared to non-responders. Patients with high BF (>106 ml/100 g/min) at baseline were five times more likely (p = 0.004) to respond to treatment as compared to those with low BF. BF was found to be 83.3% predictive of complete response. Other perfusion parameters were not significantly predictive of outcome (p > 0.05) Combination of high BF (>106 ml/100 g/min) and low (≤47 ml/100 g/min) permeability surface (PS) was 100% predictive of response to CRT irrespective of the stage of tumor.

Conclusions

High BF at baseline is the single best predictor of response to chemoradiaton. A combination of high BF and low PS was found to be 100% predictive of complete response irrespective of the stage of the tumor.

Effect of increasing the sampling interval to 2 seconds on the radiation dose and accuracy of CT perfusion of the head and neck

PURPOSE

To evaluate the effect of increasing the sampling interval from 1 second (1 image per second) to 2 seconds (1 image every 2 seconds) on computed tomographic (CT) perfusion (CTP) of head and neck tumors.

MATERIALS AND METHODS

Twenty patients underwent CTP studies of head and neck tumors with images acquired in cine mode for 50 seconds using sampling interval of 1 second. Using deconvolution-based software, analysis of CTP was done with sampling interval of 1 second and then 2 seconds. Perfusion maps representing blood flow, blood volume, mean transit time, and permeability surface area product (PS) were obtained. Quantitative tumor CTP values were compared between the 2 sampling intervals. Two blinded radiologists compared the subjective quality of CTP maps using a 3-point scale between the 2 sampling intervals. Radiation dose parameters were recorded for the 2 sampling interval rates.

RESULTS

No significant differences were observed between the means of the 4 perfusion parameters generated using both sampling intervals; all P >0.05. The 95% limits of agreement between the 2 sampling intervals were -65.9 to 48.1) mL/min per 100 g for blood flow, -3.6 to 3.1 mL/100 g for blood volume, -2.9 to 3.8 seconds for mean transit time, and -10.0 to 12.5 mL/min per 100 g for PS. There was no significant difference between the subjective quality scores of CTP maps obtained using the 2 sampling intervals; all P > 0.05. Radiation dose was halved when sampling interval increased from 1 to 2 seconds.

CONCLUSIONS

Increasing the sampling interval rate to 1 image every 2 seconds does not compromise the image quality and has no significant effect on quantitative perfusion parameters of head and neck tumors. The radiation dose is halved.

Measurement of tumor blood flow in head and neck squamous cell carcinoma by pseudo-continuous arterial spin labeling: comparison with dynamic contrast-enhanced MRI

PURPOSE

To investigate the feasibility of tumor blood flow (TBF) measurement in head and neck squamous cell carcinoma (HNSCC) using pseudo-continuous arterial spin labeling (pCASL) in a comparison with dynamic contrast-enhanced (DCE) perfusion.

MATERIALS AND METHODS

We prospectively scanned 18 patients with HNSCC using 3T magnetic resonance imaging (MRI) with both pCASL and DCE perfusion. Quantitative TBF value in the whole-tumor region of interest (ROI), and regional TBF in the ROIs of the central and peripheral areas in the tumor were respectively measured. Relative TBF value in the whole-tumor ROI was also calculated. We determined the correlation and agreement between each measured TBF by pCASL and DCE perfusion using Pearson's correlation coefficients, intraclass correlation coefficients (ICC), and Bland-Altman analysis.

RESULTS

In the whole-tumor ROIs, significant correlation was observed between the absolute TBF values (r = 0.72, P < 0.01), with an ICC of 0.72; moreover, higher correlation was observed in the relative TBF (r = 0.79). The correlation was higher in the peripheral ROI (r = 0.70) than the central ROI (r = 0.65), with an ICC of 0.62 and 0.54, respectively. Bland-Altman plots revealed the underestimation of TBF by pCASL in central ROIs.

CONCLUSION

TBF measurement by pCASL was feasible in patients with HNSCC.

Perfusion CT of head and neck cancer

We aim to review the technique and clinical applications of perfusion CT (PCT) of head and neck cancer. The clinical value of PCT in the head and neck includes detection of head and neck squamous cell carcinoma (HNSCC) as it allows differentiation of HNSCC from normal muscles, demarcation of tumor boundaries and tumor local extension, evaluation of metastatic cervical lymph nodes as well as determination of the viable tumor portions as target for imaging-guided biopsy. PCT has been used for prediction of treatment outcome, differentiation between post-therapeutic changes and tumor recurrence as well as monitoring patient after radiotherapy and/or chemotherapy. PCT has a role in cervical lymphoma as it may help in detection of response to chemotherapy and early diagnosis of relapsing tumors.

Assessment of response to sorafenib in advanced hepatocellular carcinoma using perfusion computed tomography: results of a pilot study

AIMS

This prospective pilot study investigated the feasibility of perfusion computed tomography parameters as surrogate markers of angiogenesis and early response following sorafenib administration in patients with advanced hepatocellular carcinoma.

METHODS

Ten patients were evaluated with perfusion computed tomography before starting sorafenib and after 3 months. Blood flow, blood volume, mean transit time, hepatic arterial fraction, and permeability surface-product were compared in tumour lesions and in hepatic parenchyma at baseline and at follow-up. Correlation between these parameters and changes in alpha-fetoprotein levels was calculated.

RESULTS

At baseline, blood volume, blood flow, hepatic arterial fraction and permeability surface values were higher in lesions compared to those in hepatic parenchyma, while mean transit time was lower (p<0.05). After sorafenib treatment, only mean transit time was significantly increased versus baseline (p<0.05). At follow-up, plasma alpha-fetoprotein levels decreased in all patients. At follow-up, an inverse correlation was observed between baseline mean transit time and changes in alpha-fetoprotein (r=-0.6685, p=0.0125), as well as a correlation between baseline blood flow and alpha-fetoprotein (r=0.6476, p=0.0167).

CONCLUSION

This pilot study suggests that after sorafenib treatment an increase in mean transit time observed in tumour lesions is inversely correlated with alpha-fetoprotein reductions after therapy. Mean transit time may represent a possible marker of response irrespectively of alpha-fetoprotein values.

Prediction of locoregional control in head and neck squamous cell carcinoma with serial CT perfusion during radiotherapy

BACKGROUND AND PURPOSE

Tumor hypoxia is a known factor of radioresistance in HNSCC. CTP is a noninvasive method of measuring tumor perfusion in vivo. The purpose of our study was to determine serial changes in tumor perfusion in HNSCC during a course of RT by using CTP and to correlate tumor perfusion measurements to LRC.

MATERIALS AND METHODS

A prospective study was performed in 15 patients with HNSCC receiving definitive RT who underwent serial CTP before RT; at weeks 2, 4, and 6 of RT; and 6 weeks after RT. The median follow-up was 28 months (range, 6-44 months). Thirteen patients achieved LRC, and 2 patients had LRF. Tumor perfusion parameters, including BF, BV, MTT, and CP, were obtained by using a deconvolution-based analysis.

RESULTS

Pretreatment tumor BF was significantly higher in patients who achieved LRC, 118.0 mL/100 g/min, compared with those with LRF, 53.4 mL/100 g/min (P = .004). Similarly, pretreatment CP was higher in patients with LRC, 16.6 mL/100 g/min, compared with those with LRF, 7.7 mL/100 g/min (P = .02). At week 2 of RT, tumor BF parameters showed a 27.5% increase versus an 18.1% decrease from pretreatment BF values (P = .046) in patients with LRC and LRF, respectively. A decrease in BF and BV was observed in both groups 6 weeks after RT compared with these values at baseline scanning.

CONCLUSIONS

An increase in tumor BF and CP by using CTP early during a course of RT predicts LRC in patients with HNSCC treated with RT.

Intraobserver and interobserver agreement of volume perfusion CT (VPCT) measurements in patients with lung lesions

OBJECTIVES

To evaluate intraobserver and interobserver agreement of manually encompassed lung lesions for perfusion measurements using volume-perfusion computed tomography (VPCT).

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained. HIPAA guidelines were followed. A 65-s dynamic study was acquired with scan parameters 80 kV, 60 mAs (80 mAs for patients ≥ 70 kg), 128 × 0.6mm collimation. Blood flow (BF), blood volume (BV) and K(trans) parameters were determined by syngo volume perfusion CT body with 88 lesions analyzed retrospectively.

RESULTS

Within-subject coefficients of variation for intraobserver agreement (range 6.59-12.82%) were superior to those for interobserver agreement (range 21.75-38.30%). Size-dependent analysis revealed lower agreements for lesions <4 cm as compared to larger lesions. Additionally, agreements of the upper, middle and lower lung zones were different.

CONCLUSIONS

Intraobserver agreement was substantial for VPCT lung cancer perfusion measurements encouraging the use for tumor characterization and therapy response monitoring. Interobserver agreement is limited and unexperienced readers should be trained before using this new method.

Non-invasive imaging of angiogenesis in head and neck squamous cell carcinoma

Squamous cell carcinoma of the head and neck (HNSCC) is the seventh most common cancer in the United States. Angiogenesis, the process by which new blood vessels are formed, is an essential element at the basis of both tumor growth and metastases. This review discusses pertinent aspects of the role of imaging modalities in assessing angiogenesis and anti-angiogenic therapy in advanced HNSCC.