Amide proton transfer MRI detects early changes in nasopharyngeal carcinoma: providing a potential imaging marker for treatment response.

PURPOSE: To determine if treatment of nasopharyngeal carcinoma (NPC) induces early changes in amide proton transfer-weighted (APTw) magnetic resonance imaging (MRI), and to perform a preliminary evaluation of APTw imaging in response assessment. METHODS: Sixteen patients with NPC planned for treatment with radiotherapy and/or chemotherapy underwent APTw imaging of the primary tumour pre-treatment and 2-week intra-treatment. Difference in pre- and intra-treatment APT mean (APTmean) was compared using the Wilcoxon signed rank test. Differences in APTmean and percentage change (%Δ) in APTmean were compared between responders and non-responders based on the outcome at 6 months, using the Mann-Whitney U test. RESULTS: APTmean decreased in 9/16 (56.3%) and increased in 7/16 (43.7%) with no significant difference between the pre- and intra-treatment APT values for the whole group (p > 0.05). NPC showed response in 11/16 (68.8%) and non-response in 5/11 (31.2%). There were significant differences between the %Δ of responders and non-responders for APTmean (p = 0.01). Responders showed %Δ decrease in APTmean of - 23.12% while non-responders showed a %Δ increase in APTmean of + 102.28%. CONCLUSION: APT value changes can be detected in early intra-treatment. Intra-treatment %Δ APTmean shows potential in predicting short-term outcome.

Head and Neck Tumors: Amide Proton Transfer MRI.

Purpose To evaluate the utility of amide proton transfer (APT) imaging in the characterization of head and neck tumors. Materials and Methods This retrospective study of APT imaging included 117 patients with 70 nasopharyngeal undifferentiated carcinomas (NUCs), 26 squamous cell carcinomas (SCCs), eight non-Hodgkin lymphomas (NHLs), and 13 benign salivary gland tumors (BSGTs). Normal tissues were examined in 25 patients. The APT means of malignant tumors, normal tissues, and benign tumors were calculated and compared with the Student t test and analysis of variance. The added value of the mean APT to the mean apparent diffusion coefficient (ADC) for differentiating malignant and benign tumors was evaluated by using receiver operating characteristic analysis and integrated discrimination index. Results The mean APT of malignant tumors (2.40% ± 0.97 [standard deviation]) was significantly higher than that of brain tissue (1.13% ± 0.43), muscle tissue (0.23% ± 0.73), and benign tumors (1.32% ± 1.20) (P < .001). There were no differences between malignant groups (NUC, 2.37% ± 0.90; SCC, 2.41% ± 1.16; NHL, 2.65% ± 0.89; P = .45 to P = .86). The mean ADC of malignant tumors ([0.85 ± 0.17] × 10-3 mm2/sec) was significantly lower than that of benign tumors ([1.46 ± 0.47] × 10-3 mm2/sec) (P = .001). Adding APT to ADC increased the area under the curve from 0.87 to 0.96, with an integrated discrimination index of 7.6% (P = .13). Conclusion These preliminary data demonstrate differences in amide proton transfer (APT) mean of malignant tumors, normal tissues, and benign tumors, although APT mean could not be used to differentiate between malignant tumor groups. APT imaging has the potential to be of added value to apparent diffusion coefficient in differentiating malignant from benign tumors.

Nasopharyngeal carcinoma: relationship between invasion of the prevertebral space and distant metastases.

PURPOSE: To identify primary sites of nasopharyngeal carcinoma (NPC) invasion on the staging head and neck magnetic resonance imaging (MRI) that correlate with distant metastases (DM). MATERIALS AND METHODS: Staging head and neck MRI examinations of 579 NPC patients were assessed for primary tumour invasion into 16 individual sites, primary stage (T) and nodal stage (N). Results were correlated with distant metastasis-free survival (DMFS) using the Cox regression, and the diagnostic performance of significant independent markers for DM was calculated. In addition, sites of primary tumour invasion were correlated also with involvement of the first echelon of ipsilateral nodes (FEN+) using logistic regression. RESULTS: Distant metastases were present in 128/579 NPC patients (22.1%) after intensity-modulated radiotherapy (IMRT)/chemo-IMRT and 5-year DMFS was 78.8%. Prevertebral space invasion (PVS+) and N stage, but not T stage, were independent prognostic markers of DMFS (p = 0.016, < 0.001, and 0.433, respectively). Compared to stage N3, PVS invasion had a higher sensitivity (28.1 vs. 68.8%), but lower specificity (90.5 vs. 47.4%) and accuracy (76.7 vs. 48.9%) for correlating patients with DM. PVS invasion, together with parapharyngeal fat space invasion (PPFS+), was also an independent predictive marker of FEN+. CONCLUSION: PVS was the only site of primary tumour invasion that independently correlated with DM, and together with PPFS + was an independent prognostic marker of FEN+, but the low specificity and accuracy of PVS invasion limits its use as a prognostic marker of DM.

MRI of diffuse large B-cell non-Hodgkin's lymphoma of the head and neck: comparison of Waldeyer's ring and sinonasal lymphoma.

To document the magnetic resonance imaging (MRI) features of diffuse large B-cell lymphoma (DLBCL) in Waldeyer's ring (WR) and the sinonasal (SN) region, and to identify any differences between lymphatic and extra-lymphatic DLBCLs, and predictors of disease beyond the neck. Primary, nodal, and multifocal sites on head and neck MRI were compared between 31 WR and 15 SN DLBCL, and between 27 patients with disease confined to the head and neck and 16 patients with disease beyond the neck, using logistic regression. Compared to SN, WR DLBCLs had significantly smaller primary tumour volumes (p = 0.009), less deep invasion (p = 0.001), and more nodal disease (p = 0.016). Tumour site (WR vs. SN) was an independent predictor of deep invasion (p = 0.007). Nodal and multifocal diseases were predictors of disease beyond the neck (p = 0.027 and 0.011, respectively). Lymphatic WR DLBCLs were less locally aggressive but had greater propensity to nodal spread than extra-lymphatic SN DLBCLs. Nodal and multifocal diseases predicted disease beyond the neck.

Diffusion-weighted imaging of nasopharyngeal carcinoma to predict distant metastases.

Our study aimed to identify diffusion-weighted imaging (DWI) parameters obtained from primary nasopharyngeal carcinoma (NPC) at initial presentation, that can predict patients at risk of distant metastases. One hundred and sixty-four patients underwent pretreatment magnetic resonance imaging and DWI. The apparent diffusion coefficient (ADC)mean, ADCskewness, and ADCkurtosis were obtained by histogram analysis. Univariate and multivariate analyses of these ADC parameters together with primary volume (PV), nodal volume (NV), T stage, N stage and presence of locoregional relapse (LRR) were compared between patients with distant metastases (DM+) and patients without distant metastases (DM-) at 5 years using logistic regression. Twenty-eight out of 164 patients (17.1 %) were DM+ (2.5-60 months) and 136/164 patients were DM- (61.2-119.4 months). Compared to DM- patients, the primary tumour of DM+ patients showed significantly lower ADCskewness (ADC values with the greatest frequency were higher) (p = 0.041), and higher PV (p = 0.022), NV (p < 0.01), T stage (p = 0.023), N stage (p < 0.01) and LRR (p < 0.01). On multivariate analysis the ADCskewness was no longer significant (p = 0.120) and only NV and LRR were independent predictors for DM+ (p = 0.023 and 0.021, respectively). DWI showed that compared to DM- patients, DM+ patients had a significantly lower primary tumour ADCskewness, but at initial presentation NV was the only independent predictor of DM.

Acute diffuse thyroid swelling: A rare complication of fine-needle aspiration.

We present a case illustrating the rare complication of acute generalized thyroid swelling shortly after sonographic-guided fine needle aspiration of a thyroid nodule. Ultrasound revealed the presence of characteristic linear hypoechoic avascular areas interspersed throughout the gland suggestive of edema. The patient was treated conservatively, with near complete normalization of the thyroid within 24 hours. Recognition of this potential complication is important, as the rapid onset of diffuse thyroid enlargement is often alarming but typically has a transient and self-limiting course. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:426-429, 2017.

CT pre-operative planning of a new semi-implantable bone conduction hearing device.

PURPOSE: Accommodating a novel semi-implantable bone conduction hearing device within the temporal bone presents challenges for surgical planning. This study describes the utility of CT in pre-operative assessment of such an implant. METHODS: Retrospective review of pre-operative CT, clinical and surgical records of 16 adults considered for device implantation. Radiological suitability was assessed on CT using 3D simulation software. Antero-posterior (AP) dimensions of the mastoid bone and minimum skull thickness were measured. CT planning results were correlated with operative records. RESULTS: Eight and five candidates were suitable for device placement in the transmastoid and retrosigmoid positions, respectively, and three were radiologically unsuitable. The mean AP diameter of the mastoid cavity was 14.6 mm for the transmastoid group and 4.6 mm for the retrosigmoid group (p < 0.05). Contracted mastoid and/or prior surgery were predisposing factors for unsuitability. Four transmastoid and five retrosigmoid positions required sigmoid sinus/dural depression and/or use of lifts due to insufficient bone capacity. CONCLUSION: A high proportion of patients being considered have contracted or operated mastoids, which reduces the feasibility of the transmastoid approach. This finding combined with the complex temporal bone geometry illustrates the importance of careful CT evaluation using 3D software for precise device simulation. KEY POINTS: • Preoperative temporal bone CT is essential for determining Bonebridge device suitability. • Mastoid under-pneumatisation and prior mastoidectomy predict a retrosigmoid Bonebridge position. • 3D simulation software is recommended for precise device positioning.

Amide proton transfer-weighted imaging of the head and neck at 3 T: a feasibility study on healthy human subjects and patients with head and neck cancer.

The aim of this study was to explore the feasibility and repeatability of amide proton transfer-weighted (APTw) MRI for the head and neck on clinical MRI scanners. Six healthy volunteers and four patients with head and neck tumors underwent APTw MRI scanning at 3 T. The APTw signal was quantified by the asymmetric magnetization transfer ratio (MTRasym) at 3.5 ppm. Z spectra of normal tissues in the head and neck (masseter muscle, parotid glands, submandibular glands and thyroid glands) were analyzed in healthy volunteers. Inter-scan repeatability of APTw MRI was evaluated in six healthy volunteers. Z spectra of patients with head and neck tumors were produced and APTw signals in these tumors were analyzed. APTw MRI scanning was successful for all 10 subjects. The parotid glands showed the highest APTw signal (~7.6% average), whereas the APTw signals in other tissues were relatively moderate. The repeatability of APTw signals from the masseter muscle, parotid gland, submandibular gland and thyroid gland of healthy volunteers was established. Four head and neck tumors showed positive mean APTw ranging from 1.2% to 3.2%, distinguishable from surrounding normal tissues. APTw MRI was feasible for use in the head and neck regions at 3 T. The preliminary results on patients with head and neck tumors indicated the potential of APTw MRI for clinical applications.

Extraocular muscle Diffusion Weighted Imaging as a quantitative metric of posterior orbital involvement in thyroid associated orbitopathy.

OBJECTIVES: The clinical activity score (CAS) and European severity scale (ESS) are established clinical tools to assess thyroid eye disease (TED) but are limited in terms of subjectivity and their reliability in non-Caucasian individuals, and can underestimate significant disease in the posterior orbit. Preliminary data from pilot studies have shown that diffusion-weighted imaging (DWI) using extraocular muscle (EOM) apparent diffusion coefficient (ADC) measurements may provide complementary information in TED. This study expands on previous research to assess for correlations between clinical scores and EOM-ADCs in stratifying disease activity and severity in a large patient cohort from an ethnically diverse population. METHODS: A retrospective review of TED clinics between 2011 and 2021 identified 96 patients with a documented CAS and ESS and an orbital MRI that included DWI. From regions of interest manually placed on EOM bellies, the highest ADC was computed for each patient and analysed for correlations and associations with CAS and ESS using Spearman Rank correlation and Mann-Whitney U tests, and any potential discriminatory cut-offs using Receiver Operator Curve analyses. A p-value < 0.05 indicated statistical significance. RESULTS: EOM-ADCs showed a positive association with CAS (p ≤ 0.001). EOM-ADCs were higher in sight-threatening compared to mild disease (p ≤ 0.01). A cut-off of 995 mm2/s achieved AUC = 0.7744, equating to 77% sensitivity and 67% specificity for discrimination between mild-moderate and sight-threatening disease. CONCLUSION: EOM-ADCs correlate with higher scores of disease severity and activity in TED. Besides providing quantitative data to support clinical tools, EOM-ADC cut-offs may identify patients at risk of developing sight-threatening diseases. CRITICAL RELEVANCE STATEMENT: This study critically evaluates the limitations of conventional clinical assessment tools for TED and demonstrates the utility of DWI scans with ADC measurements in identifying active disease, offering valuable insights to advance clinical radiology practice. KEY POINTS: Conventional tools for TED assessment have subjective limitations. ADCs from non-echoplanar diffusion-weighted imaging correlate with clinical activity. Non-echoplanar diffusion-weighted imaging offers quantitative assessment to aid clinical practice reliability.

Head and neck squamous cell carcinoma: diagnostic performance of diffusion-weighted MR imaging for the prediction of treatment response.

PURPOSE: To determine the diagnostic performance of diffusion-weighted (DW) imaging for the prediction of treatment failure in primary head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: The study was approved by the local institutional ethics committee and conducted with informed written consent in patients with primary HNSCC treated with radiation therapy and chemotherapy. DW imaging of the primary tumor was performed before treatment in 37 patients and was repeated within 2 weeks of treatment in 30 patients. Histograms of apparent diffusion coefficients (ADCs) were analyzed, and mean ADC, kurtosis, skewness, and their respective percentage change were correlated for local failure and local control at 2 years by using the Student t test. Univariate and multivariate analyses of the ADC parameters, T stage, and tumor volume were performed by using logistic regression for prediction of local failure. RESULTS: Local failure occurred in 16 of 37 (43%) patients and local control occurred in 21 of 37 (57%) patients. Pretreatment ADC parameters showed no correlation with local failure. There was significant intratreatment increase in mean ADC and a decrease in skewness and kurtosis (P < .001, P < .001, P = .024, respectively) for the whole group of patients when compared with those before treatment. During treatment, primary tumors showed a significantly lower increase in percentage change of mean ADC, higher skewness, and higher kurtosis for local failure than for local control (P = .016, .015, and .040, respectively). These ADC parameters also were significant for predicting local failure with use of univariate but not multivariate analysis. CONCLUSION: Early intratreatment DW imaging has the potential to allow prediction of treatment response at the primary site in patients with HNSCC.

Discriminating between benign and malignant salivary gland tumors using diffusion-weighted imaging and intravoxel incoherent motion at 3 Tesla.

PURPOSE: The purpose of this study was to retrospectively evaluate the diagnostic performances of diffusion-weighted imaging (DWI) and intravoxel incoherent motion (IVIM) for discriminating between benign and malignant salivary gland tumors (SGTs). MATERIALS AND METHODS: Sixty-seven patients with 71 SGTs who underwent MRI examination at 3 Tesla were included. There were 34 men and 37 women with a mean age of 57 ± 17 (SD) years (age range: 20-90 years). SGTs included 21 malignant tumors (MTs) and 50 benign SGTs (33 pleomorphic adenomas [PAs] and 17 Warthin's tumors [WTs]). For each SGT, DWI and IVIM parameters, mean, skewness, and kurtosis of apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*) and perfusion volume fraction (f) were calculated and further compared between SGTs using univariable analysis. Areas under the curves (AUC) of receiver operating characteristic of significant parameters were compared using the Delong test. RESULTS: Significant differences in ADCmean, Dmean and D*mean were found between SGTs (P < 0.001). The highest AUC values were obtained for ADCmean (0.949) for identifying PAs and D*mean (0.985) for identifying WTs and skewness and kurtosis did not outperform mean. To discriminate benign from malignant SGTs with thresholds set to maximize Youden index, IVIM and DWI produced accuracies of 85.9% (61/71; 95% CI: 75.6-93.0) and 77.5% (55/71; 95% CI: 66.0-86.5) but misdiagnosed MTs as benign in 28.6% (6/21) and 61.9% (13/21) of SGTs, respectively. After maximizing specificity to 100% for benign SGTs, the accuracies of IVIM and DWI decreased to 76.1% (54/71; 95% CI: 64.5-85.4) and 64.8% (46/71; 95% CI: 52.5-75.8) but no MTs were misdiagnosed as benign. IVIM and DWI correctly diagnosed 66.0% (33/50) and 50.0% (25/50) of benign SGTs and 46.5% (33/71) and 35.2% (25/71) of all SGTs, respectively. CONCLUSION: IVIM is more accurate than DWI for discriminating between benign and malignant SGTs because of its advantage in detecting WTs. Thresholds set by maximizing specificity for benign SGTs may be advantageous in a clinical setting.

Nasopharyngeal mucosa and adenoids: appearance at MR imaging.

PURPOSE: To document the magnetic resonance (MR) imaging appearances of benign nasopharyngeal mucosa and adenoids and to correlate quantitative thickness measurements with histologic findings from nasopharyngeal biopsy specimens. MATERIALS AND METHODS: MR imaging studies and nasopharyngeal biopsy specimens were analyzed retrospectively in 100 adults (51 men, 49 women) with benign histologic findings; local institutional review board approval and informed consent had been obtained as part of a previous imaging study. At T1-weighted gadolinium-enhanced MR imaging, the nasopharyngeal roof and adenoid was classified as follows: 1, pencil thin, less than 3 mm; 2, smooth thickening, 3 mm or larger; 3, small tags or stripes; or 4, focal adenoid mass with a vertical striped appearance. The posterior and lateral walls were classified as follows: pattern 1, pencil thin, less than 3 mm; pattern 2, mild thickening, 3 mm or larger with moderate enhancement; or pattern 3, thickening with hypoenhancement along the posterior wall. The frequency of these patterns, as well as cysts, symmetry, and pharyngeal recess patency, were documented. Wall thickness was measured and correlated with age, sex, and histologic findings from biopsy specimens by using Spearman rank correlation and Mann-Whitney U tests. RESULTS: In 100 patients, roof patterns 1-4 were identified in 16 (16%), seven (7%), 33 (33%), and 44 (44%); posterior and lateral wall patterns 1-3 were identified in 20 (20%), 55 (55%), and 25 (25%) patients. Symmetry was identified in 95 (95%) patients, cysts in 41 (41%) patients, and pharyngeal recess patency was identified in 24 (12%) of 200 sides. Roof including adenoid thickness was higher in men (P = .05) and correlated inversely with age (P <.01). In 62 (62%) of 100 patients, biopsy specimens contained lymphoid follicles. Roof including adenoid (P = .01) and posterior wall (P = .03) thickness at MR imaging was higher if follicles were identified in biopsy specimens. CONCLUSION: Nasopharyngeal hyperplasia has typical MR imaging appearances, including stripes in adenoid bulges and symmetry, which may be useful to differentiate this condition from nasopharyngeal malignancy.

Shear wave elastography of focal salivary gland lesions: preliminary experience in a routine head and neck US clinic.

OBJECTIVES: To evaluate shear wave elastography (SWE) for focal lesions in major salivary glands. METHODS: Sixty lesions (49 parotid, 11 submandibular) undergoing routine ultrasound (grey scale and Doppler) also underwent SWE before US-guided needle aspiration for cytology. Quantitative indices of the shear elastic modulus (stiffness) were compared with cytological results. RESULTS: Fifty-five lesions were benign (21 pleomorphic adenomas, 18 Warthin's tumours; 16 others) and 5 malignant (2 mucoepidermoid carcinomas, 1 myoepithelial carcinoma, 1 B-cell lymphoma, 1 nodal metastasis). Shear modulus of benign lesions, median 18.3 kPa, overlapped appreciably with malignant lesions, median 13.5 kPa. However, 2 mucoepidermoid carcinomas had the highest stiffness values (81.9 kPa, 132.0 kPa). Stiffness of pleomorphic adenomas (median 22.5 kPa) was higher than Warthin's tumours (16.9 kPa) (P = 0.05 Mann-Whitney U-test). The standard deviation of stiffness values within a lesion, used as an indicator of spatial heterogeneity, was highest in mucoepidermoid cancers (median 44.2 kPa), followed by pleomorphic adenomas (median 12.4 kPa) and remaining lesions (medians 1.4-10.3 kPa). CONCLUSION: This study shows a degree of clustering of SWE indices according to pathology although it appears that SWE has suboptimal performance for ruling out malignancy, thus limiting its use in routine practice. KEY POINTS: • Shear wave elastography is a feasible technique for focal salivary gland lesions. • Elastographic artefacts aggravated by the regional anatomy may hinder this technique. • Elastographic indices vary according to pathology but there is appreciable overlap. • Overlapping indices for malignant and benign lesions limit its utility. • Pleomorphic adenomas have higher elasticity indices, i.e. are stiffer, than Warthin's tumours.

Shear wave elastography of thyroid nodules in routine clinical practice: preliminary observations and utility for detecting malignancy.

OBJECTIVE: To evaluate real-time shear wave ultrasound elastography (SWE) for characterizing focal thyroid lesions in routine clinical practice. METHODS: Seventy-four patients with 81 focal thyroid lesions undergoing conventional US with needle cytology also underwent SWE. Absolute and relative SWE stiffness measurements on colour-coded elastograms were correlated with cytology and their discriminatory performances assessed. RESULTS: Seventeen nodules were malignant (13 papillary, 4 other cancers), 45 benign (43 hyperplastic nodules, 2 focal thyroiditis), 5 indeterminate ("follicular lesions"), and 5 had inadequate cytology. SWE results were higher in malignant than benign nodules (P values 0.02-0.05) although their discriminatory performances were mediocre (AUCs 0.58-0.74). The most accurate SWE cut-off, 34.5 kPa for a 2-mm region of interest, achieved 76.9 % sensitivity and 71.1 % specificity for discriminating papillary cancer from benign nodules. No thresholds produced high sensitivity without lowering specificity appreciably, and vice versa. Nodule size correlated with SWE for benign nodules (P < 0.01). Intranodular cystic change or calcification did not influence SWE. Qualitatively, elastographic artefacts and foci lacking colour elasticity signal occurred in some solid nodules. CONCLUSION: Although malignant nodules are generally stiffer than benign nodules, the precision results do not suggest a definitive role for SWE, at present, in identifying or excluding thyroid malignancy. KEY POINTS : • Shear wave ultrasound elastography (SWE) offers new insight into thyroid disease. • Papillary cancers have higher SWE indices (equating to higher stiffness) than benign nodules. • SWE appears limited in terms of identifying or excluding thyroid malignancy accurately. • Vertically aligned elastographic artefacts can occur in thyroid SWE. • Areas lacking SWE colour signal can occur in some solid thyroid nodules.

Primary nasopharyngeal carcinoma: diagnostic accuracy of MR imaging versus that of endoscopy and endoscopic biopsy.

PURPOSE: To compare the accuracy of magnetic resonance (MR) imaging with that of the current clinical standard of endoscopy and endoscopic biopsy, to determine whether MR imaging depicts subclinical cancers missed at endoscopy and endoscopic biopsy, and to determine whether MR imaging can identify patients without nasopharyngeal carcinoma (NPC) who do not need to undergo invasive sampling biopsy. MATERIALS AND METHODS: The study protocol was approved by the institutional review board; written informed consent was obtained from all patients. Patients suspected of having NPC underwent MR imaging, endoscopy, and endoscopic biopsy. Endoscopic biopsy targeted the suspected tumor or sampled the endoscopically normal nasopharynx. The final diagnosis was based on results of the endoscopic biopsy or on results of a repeat biopsy directed at the lesion detected at MR imaging. The sensitivity and specificity of the three investigations were compared by using the Fisher exact test. RESULTS: NPC was present in 77 (31%) of 246 patients and absent in 169 (69%) patients. The combined sensitivity, specificity, and accuracy, respectively, were 100%, 93%, and 95% for MR imaging, 90%, 93%, and 92% for endoscopy, and 95%, 100%, and 98% for endoscopic biopsy. Benign disease was mistaken for NPC in 12 (7%) of 169 patients at MR imaging and in 11 (6%) patients at endoscopy. The sensitivity of MR imaging was significantly higher than that of endoscopy (P = .006) and was similar to that of endoscopic biopsy (P = .120). The specificity of MR imaging was similar to that of endoscopy (P = .120) and was significantly lower than that of endoscopic biopsy (P < .001). CONCLUSION: MR imaging is an accurate test for the diagnosis of NPC. MR imaging depicts subclinical cancers missed at endoscopy and endoscopic biopsy and helps identify the majority of patients who do not have NPC and who therefore do not need to undergo invasive sampling biopsies.

Imaging of head and neck mucosa-associated lymphoid tissue lymphoma (MALToma).

Marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALToma) arises in extranodal sites in the head and neck. Chronic inflammatory, infectious or autoimmune conditions are implicated in its pathogenesis. Within the head and neck, MALToma is often multifocal and indolent and the imaging appearances may be mistaken for non-malignant disease in the head and neck. The aim of this article is to illustrate the varied radiological and clinical features of MALToma in the head and neck, an awareness of which is needed for timely and correct diagnosis to guide subsequent disease management.

Pretreatment and early intratreatment prediction of clinicopathologic response of head and neck cancer to chemoradiotherapy using 1H-MRS.

PURPOSE: To determine if choline (cho) identified by proton magnetic resonance spectroscopy ((1)H-MRS) performed pretreatment and early in the course of treatment predicts clinicopathologic response of head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: In all, 60 patients with HNSCC scheduled to undergo concurrent chemoradiotherapy or radiotherapy alone were recruited. (1)H-MRS was performed pretreatment and early intratreatment (2 weeks after start of treatment). Cho:creatine and cho:water ratios at each timepoint and change in the ratios between the two timepoints were correlated with locoregional failure, distant metastases, overall survival, and cancer-related death. Statistical analysis was performed using logistic regression and chi-square and a P-value of < 0.05 was considered statistically significant. RESULTS: Cho was identified in 47/49 successful pretreatment spectra and 42 of these 47 underwent successful (1)H-MRS early intratreatment, of which 21 showed persistent cho. Locoregional failure occurred in 15, distant metastases in 6, and death in 15 patients; the follow-up period in survivors ranged from 13-64 months (mean, 39 months). No statistically significant correlation was found between (1)H-MRS parameters and clinical endpoints. CONCLUSION: The pretreatment cho and change in cho early during a course of treatment did not predict clinical outcome.

Evaluation of real-time qualitative sonoelastography of focal lesions in the parotid and submandibular glands: applications and limitations.

OBJECTIVE: To evaluate qualitative ultrasound elastography for focal salivary gland masses identified during routine clinical practice. METHODS: Sixty-five parotid or submandibular masses in 61 patients underwent real-time qualitative ultrasound elastography and were scored on colour-scaled elastograms in terms of their stiffness relative to adjacent normal salivary parenchyma from ES 1 (soft) to ES 4 (stiff). This was correlated with diagnosis from aspiration cytology or histology. RESULTS: There were 29 Warthin's tumours (WTs), 23 pleomorphic adenomas (PAs), 2 adenoid cystic carcinomas, 1 adenosquamous carcinoma, 1 nodal metastasis from nasopharyngeal carcinoma, 1 lymphoma (2 deposits), 3 Kuttner tumours and 4 cases of Kimura's disease. ES scores showed clustering according to pathological condition. In this respect, PAs were firmer than WTs (P < 0.004, Fisher's exact test). Nine, 19, 14 and 17 of the benign masses and 0, 1, 2 and 3 of the malignant masses were ES 1, 2, 3 and 4 respectively. All three primary salivary malignancies were ES 4 compared with 1/29 WTs and 16/23 PAs. CONCLUSION: These preliminary findings suggest that qualitative real-time ultrasound elastography, although an ancillary technique to conventional ultrasound in the salivary glands, is likely to have a poor ability to discriminate benign lesions (particularly PAs) from malignant disease.

Squamous cell carcinoma of the head and neck: diffusion-weighted MR imaging for prediction and monitoring of treatment response.

OBJECTIVE: To investigate the role of diffusion-weighted imaging (DWI) in predicting and monitoring chemoradiotherapy response in head and neck squamous cell carcinoma (HNSCC). METHODS: Diffusion-weighted imaging was performed pre-treatment (n = 50), intra-treatment (n = 41) and post-treatment (n = 20). Apparent diffusion coefficient (ADC) values were correlated with locoregional failure (LF). RESULTS: Locoregional failure occurred in 20/50 (40%) patients. A significant correlation was found between LF and post-treatment ADC (p = 0.02) but not pre- or intra-treatment ADC. Serial change in ADC was even more significant (p = 0.00001), using a fall in ADC early (pre- to intra-treatment) or late (intra- to post-treatment) to indicate LF, achieved 100% specificity, 80% sensitivity and 90% accuracy. CONCLUSIONS: Single ADC measurements pre- or intra-treatment did not predict response, but ADC post-treatment was a marker for LF. Serial change in ADC was an even stronger marker, when using an early or late treatment fall in ADC to identify LF.

Monitoring of treatment response after chemoradiotherapy for head and neck cancer using in vivo 1H MR spectroscopy.

Elevated choline (Cho) level has been documented on proton magnetic resonance spectroscopy ((1)H MRS) in head and neck squamous cell carcinoma and therefore percentage changes in Cho levels after chemoradiotherapy may serve as a marker of residual cancer in a post-treatment mass (PTM). Forty-six patients underwent (1)H MRS before treatment and the 30 patients with a PTM underwent repeat (1)H MRS at 6 weeks post-treatment. The percentage change in Cho/creatine and Cho/water ratios were correlated with residual cancer. The mean pretreatment Cho/creatine and Cho/water ratios were 2.24 and 1.20 x 10(-3), respectively. Cho persisted in four out of nine PTMs with residual cancer. Cho was absent in five out of nine PTMs with residual cancer and 21/21 PTMs without cancer. The number of PTMs with persistent Cho was too small to allow analysis of percentage change in ratios but the presence of Cho in a PTM showed significant correlation with residual cancer (p = 0.0046), producing a sensitivity, specificity, positive predictive value and negative predictive value of 44%, 100%, 100% and 81%, respectively. Therefore, the presence of Cho in a PTM may serve as a marker of residual cancer. Furthermore since so few PTMs contain Cho, a percentage change in Cho ratios may not be a useful method for monitoring treatment response.