Head and neck cancer: value of perfusion CT in depicting primary tumor spread

The diagnostic performance of perfusion CT in the detection of local tumor recurrence in head and neck cancer

BACKGROUND

Detecting local tumor recurrence from post-treatment changes in head and neck cancer (HNC) remains a challenge. Based on the hypothesis that post-therapeutically altered tissue is bradytroph, lower perfusion values are expected in perfusion CT (PCT) while higher perfusion values are expected in recurrent malignant tissue.

OBJECTIVES

This prospective study investigates PCT for post-treatment recurrent HNC detection with a maximum slope algorithm.

METHODS

A total of 80 patients who received PCT of the head and neck for post-therapy follow-up, of which 63 had no tumor recurrence and 17 presented a histopathologically confirmed recurrence were examined. Regions of interest were placed in the location of the initial tumor, in reference ipsilateral nuchal muscle tissue and the corresponding internal carotid artery. Perfusion was calculated using a single-input maximum slope algorithm.

RESULTS

With PCT, recurrent HNC can be differentiated from post-treatment tissue (p < 0.05). It further allows delineating recurrent tumor tissue from benign nuchal tissue of reference (p < 0.05). PCT data of patients with and without recurrent HNC are comparable as perfusion values of reference tissues in patients with and without HNC do not differ (p > 0.05).

CONCLUSIONS

PCT in combination with a commercially available maximum slope algorithm offers radiologists a reliable imaging tool to detect recurrent head and neck cancer within post-therapeutically altered tissue.

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.

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.

Differential diagnostic value of computed tomography perfusion combined with vascular endothelial growth factor expression in head and neck lesions

There are numerous types of head and neck lesions (HNLs), and conventional computed tomography (CT) has low specificity and sensitivity in the definitive and differential diagnosis of HNLs. The aim of the present study was to evaluate the value of perfusion CT (CTP) combined with vascular endothelial growth factor (VEGF) expression in the differentiation between malignant and benign HNLs. In total, 41 HNLs, which were pathologically confirmed, underwent CTP and VEGF expression analysis. All lesions were divided into three groups: Group A, benign hypovascular lesions; Group B, benign hypervascular lesions; and Group C, malignant lesions. Time density curve (TDC) and CTP parameters [maximum intensity projection (MIP), blood volume (BV), blood flow (BF), mean transit time and capillary permeability] were analyzed. The association between perfusion measurements and VEGF was assessed using Pearson's correlation. TDCs were classified into three types, and type I was more frequently identified in benign tumors (Groups A and B) compared with malignant tumors (Group C) (P=0.003). Malignant tumors primarily had a TDC of type II and III. MIP, BF and BV were all significantly higher in Groups B and C compared to Group A (P<0.01). VEGF expression of malignant tumors was significantly higher than benign tumors (P=0.007). No correlation was identified between VEGF and any CTP parameter. The present findings suggest that CTP combined with VEGF may differentiate between malignant and benign HNLs, and between benign hypovascular and hypervascular lesions.

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.