What the clinician wants to know: surgical perspective and ultrasound for lymph node imaging of the neck

On the Computation of Mean and Variance of Spatial Displacements

This paper studies the problem of computing an average (or mean) displacement from a set of given spatial displacements using three types of parametric representations: Euler angles and translation vectors, unit quaternions and translation vectors, and dual quaternions. It is shown that the use of Euclidean norm in the space of unit quaternions reduces the problem to that of computing the mean for each quaternion component separately and independently. While the resulting algorithm is simple, a change in the sign of a unit quaternion could lead to an incorrect result. A novel kinematic measure based on dual quaternions is introduced to capture the separation between two spatial displacements. This kinematic measure is used to define the variance of a set of displacements, which is then used to formulate a constrained least squares minimization problem. It is shown that the problem decomposes into that of finding the optimal translation vector and the optimal unit quaternion. The former is simply the centroid of the set of translation vectors and the latter is obtained as the eigenvector corresponding to the least eigenvalue of a 4 × 4 positive definite symmetric matrix. In addition, it is found that the weight factor used in combining rotations and translations in the formulation does not play a role in the final outcome. Examples are provided to show the comparisons of these methods.

Correlation of Sonographic Classification of Neck Adenopathy (A-RADS) and Malignancy

Introduction

Cervical adenopathy can be involved in various pathological processes. This study aimed to evaluate the ultrasound classification of cervical adenopathy (A-RADS) to choose the appropriate approach.

Materials and Methods

This cross-sectional study was conducted among 294 patients with cervical adenopathy at Mashhad University of Medical Sciences during 2020-2021. The data of the long axis diameter, short axis diameter, shape, border, vascular pattern, presence of calcification and changes in cyst/necrosis, cortical echogenicity, hilum visibility, and location of involved lymph nodes were extracted. Lymph nodes was classified into four normal, reactive, suspicious & lymphoid disorders, and metastatic groups, based on ultrasound appearance (Adenopathy-reporting and data system). Diagnostic methods included follow-up, core needle biopsy (CNB), and fine needle aspiration (FNA), and surgical results. After determining the final diagnosis, demographic, sonographic, and pathological data were analyzed at a significance level of p<0.05.

Results

Of 294 patients, 185 were benign, and 109 were malignant. There were no significant differences in the location, long axis diameter, shape, cystic or necrotic changes, calcification, and margins of the lymph nodes between the benign and malignant groups. The enlarged short axis diameter, invisible hilum with isoechoic cortex, and non-hilar vascularity were significantly higher in the malignant group (p<0.001). The malignancy rate was 8.7% in reactive cases, 48.5% in lymphoid disorders, and 90% in metastatic nodes.

Conclusion

The results of this study shows that cervical lymph nodes can be classified based on short axis diameter, cortex and hilum echo-texture and vascular pattern into normal, reactive, suspicious & lymphoid disorders, and metastatic, which have a high concordance with pathologic results.

Head and Neck Ultrasound - EFSUMB Training Recommendations for the Practice of Medical Ultrasound in Europe

Different surgical and medical specialists increasingly use head and neck ultrasound and ultrasound-guided interventions as part of their clinical practice. We need to ensure high quality and standardized practice across specialties, and this position paper of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) describes the training requirements for head and neck ultrasound. Traditionally, a minimum number of ultrasound examinations indicates competence, but this is unreliable, and a general shift towards competence-based training is ongoing. For each EFSUMB level, we will outline the theoretical knowledge and skills needed for clinical practice. The recommendations follow the three EFSUMB competency levels for medical ultrasound practice. Level 1 describes the skills required to perform essential head and neck ultrasound examinations independently, level 2 includes ultrasound-guided interventions, while level 3 involves the practice of high-level neck ultrasound and use of advanced technologies. Our goal is to ensure high quality and standardized head and neck ultrasound practice performed by different clinical specialists with these recommendations.

ADC Values of Cytologically Benign and Cytologically Malignant 18 F-FDG PET-Positive Lymph Nodes of Head and Neck Squamous Cell Carcinoma

Simple Summary

In squamous cell carcinoma of the head and neck, 18F-fluordeoxyglucose positron emission tomography (FDG-PET), diffusion-weighted magnetic resonance imaging (DW-MRI) and ultrasound-guided fine needle aspiration are commonly used imaging tools for nodal staging (N-staging). Although FDG-PET has good performance in nodal detection, it is still difficult to distinguish between PET-positive reactive and malignant nodes for the purpose of selecting nodes to be aspirated. DW-MRI can help to detect small lymph node metastases, and an inverse correlation with FDG uptake is expected. We found a mild negative correlation between SUVmax and ADC. Comparing the apparent diffusion coefficient (ADC) values between PET-positive and PET-negative nodes, ADC was significantly higher in PET-negative nodes. Whereas no significantly lower ADC value of cytological malignant nodes could be found overall, in the subgroup of non-HPV-related nodes, the ADC values of cytologically malignant PET-positive nodes were significantly lower than in cytologically benign nodes. This finding might be helpful in selecting nodes for puncture.

Abstract

Nodal staging (N-staging) in head and neck squamous cell carcinoma (HNSCC) is essential for treatment planning and prognosis. 18F-fluordeoxyglucose positron emission tomography (FDG-PET) has high performance for N-staging, although the distinction between cytologically malignant and reactive PET-positive nodes, and consequently, the selection of nodes for ultrasound-guided fine needle aspiration cytology (USgFNAC), is challenging. Diffusion-weighted magnetic resonance imaging (DW-MRI) can help to detect nodal metastases. We aim to investigate the potential of the apparent diffusion coefficient (ADC) as a metric to distinguish between cytologically reactive and malignant PET-positive nodes in order to improve node selection criteria for USgFNAC. PET-CT, real-time image-fused USgFNAC and DW-MRI to calculate ADC were available for 78 patients offered for routine N-staging. For 167 FDG-positive nodes, differences in the ADC between cytologically benign and malignant PET-positive nodes were evaluated, and both were compared to the ADC values of PET-negative reference nodes. Analyses were also performed in subsets of nodes regarding HPV status. A mild negative correlation between SUVmax and ADC was found. No significant differences in ADC values were observed between cytologically malignant and benign PET-positive nodes overall. Within the subset of non-HPV-related nodes, ADC_b0-200-1000 was significantly lower in cytologically malignant PET-positive nodes when compared to benign PET-positive nodes. ADC_b0-1000 and ADCb_0-200-1000 were significantly lower (p = 0.018, 0.016, resp.) in PET-negative reference nodes than in PET-positive nodes. ADC was significantly higher in PET-negative reference nodes than in PET-positive nodes. The non-HPV-related subgroup showed significantly (p = 0.03) lower ADC values in cytologically malignant than in cytologically benign PET-positive nodes, which should help inform the node selection procedure for puncture.

ON THE COMPUTATION OF THE AVERAGE OF SPATIAL DISPLACEMENTS

Many applications in biomechanics and medical imaging call for the analysis of the kinematic errors in a group of patients statistically using the average displacement and the standard deviations from the average. This paper studies the problem of computing the average displacement from a set of given spatial displacements using three types of parametric representations: Euler angles and translation vectors, unit quaternions and translation vectors, and dual quaternions. It has been shown that the use of Euclidean norm in the space of unit quaternions reduces the problem to that of computing the average for each quaternion component separately and independently. While the resulting algorithm is simple, the change of the sign of a unit quaternion could lead to an incorrect result. A novel kinematic measure based on dual quaternions is introduced to capture the separation between two spatial displacement. This kinematic measure is then used to formulate a constrained least squares minimization problem. It has been shown that the problem decomposes into that of finding the optimal translation vector and the optimal unit quaternion. The former is simply the centroid of the set of given translation vectors and the latter can be obtained as the eigenvector corresponding to the least eigenvalue of a 4 × 4 positive definite symmetric matrix. It is found that the weight factor used in combining rotations and translations in the formulation does not play a role in the final outcome. Examples are provided to show the comparisons of these methods.

Value of Assessing Peripheral Vascularization with Micro-Flow Imaging, Resistive Index and Absent Hilum Sign as Predictor for Malignancy in Lymph Nodes in Head and Neck Squamous Cell Carcinoma

Simple Summary

Ultrasound-guided fine needle aspiration cytology (USgFNAC) is commonly used for N-staging in head and neck squamous cell carcinoma (HNSCC). The specificity of USgFNAC is always in the order of 100% as false positive cytology is rare. The difference in sensitivity is mainly attributable to selection of the lymph nodes to aspirate and aspiration technique. The aim of this study was to improve the selection criteria of lymph nodes to aspirate. Ultrasound features of nodes such as a short axis diameter, S/L ratio, loss of a fatty hilum sign, resistive index, and peripheral or mixed hilar and peripheral vascularization, obtained by Micro-flow imaging (MFI), which is a new technique to obtain micro-vascularization, were evaluated. To calculate the sensitivity and PPV of each feature, data of sonographic findings and cytological results of all aspirated nodes were statistically analyzed. We found that next to size, peripheral vascularisation obtained by MFI and absent hilum sign have a high predictive value for malignancy and should be added as selection criteria for fine needle aspiration in lymph nodes.

Abstract

Ultrasound-guided fine needle aspiration cytology (USgFNAC) is commonly used for nodal staging in head and neck squamous cell cancer (HNSCC). Peripheral vascularity is a described feature for node metastasis. Micro-flow imaging (MFI) is a new sensitive technique to evaluate micro-vascularization. Our goal is to assess the additional value of MFI to detect malignancy in lymph nodes. A total of 102 patients with HNSCC were included prospectively. USgFNAC was performed with the Philips eL18–4 transducer. Cytological results served as a reference standard to evaluate the prediction of cytological malignancy depending on ultrasound features such as resistive index (RI), absence of fatty hilum sign, and peripheral vascularization. Results were obtained for all US examinations and for the subgroup of clinically node-negative neck (cN0). USgFNAC was performed in 211 nodes. Peripheral vascularization had a positive predictive value (PPV) of 83% (cN0: 50%) and the absence of a fatty hilum had a PPV of 82% (cN0 50%) The combination of peripheral vascularization and absent fatty hilum had a PPV of 94% (cN0: 72%). RI (threshold: 0.705) had a PPV of 61% (cN0: RI-threshold 0.615, PPV 20%), whereas the PPV of short axis diameter (threshold of 6.5mm) was 59% for all patients and 19% in cN0 necks (threshold of 4 mm). Peripheral vascularization assessed by MFI and absent hilum has a high predictive value for cytological malignancy in neck metastases. Next to size, both features should be used as additional selection criteria for USgFNAC.

SUVmax values at FDG PET-CT to predict malignancy in lymph nodes aspirated by real time image fused USgFNAC in head and neck squamous cell carcinoma

¹⁸F-fluordeoxyglucose (FDG) positron emission tomography combined with computed tomography (PET-CT) and ultrasound guided fine-needle aspiration cytology (USgFNAC) are commonly used to detect nodal metastases in head and neck squamous cell carcinoma (HNSCC). FDG PET-CT helps to guide selection of borderline suspicious nodes to aspirate using USgFNAC. Real time image fusion of FDG PET-CT with US is a new available technique and can improve this selection. The aim of this study was to determine optimal SUV_max values for USgFNAC node selection to improve USgFNAC sensitivity. 118 patients, with histopathological proven HNSCC or proven lymph nodes metastases of SCC of unknown primary, referred for staging of HNSCC with FDG PET-CT and ultrasound, were prospectively included. Additionally to standard USgFNAC of suspicious nodes fusion was performed to confirm that USgFNAC took place in FDG-positive nodes and to add Fused-USgFNAC in missed FDG-positive nodes. Fusion was performed on nodes with reported having metabolic activity. SUV_max values were measured in all Fused-USgFNAC nodes. The reference standard was cytology. In 118 patients USgFNAC was performed in 281 nodes. At fusion 22/281 (8%) nodes were FDG-negative. Out of 259 FDG-positive nodes 253 (98%) nodes were fused successfully. USgFNAC had conclusive results in 237/253 nodes (94%). In 126/237 nodes (53%) cytology proved to be tumor positive. Below SUV_max of 2.87 no fused FDG-positive nodes proved to be tumor positive at cytology. To improve sensitivity, only FDG-positive nodes with SUV_max values above 2.87 should be selected for USgFNAC. Image fusion can identify those nodes for USgFNAC selection.

Real-Time Ultrasound Image Fusion with FDG-PET/CT to Perform Fused Image-Guided Fine-Needle Aspiration in Neck Nodes: Feasibility and Diagnostic Value

BACKGROUND AND PURPOSE

New imaging techniques such as hybrid imaging of ultrasound and FDG-PET/CT are available but not yet investigated for node staging. The aim of the study was to evaluate the feasibility and added diagnostic value of real-time image-fused ultrasound-guided fine-needle aspiration with FDG-PET/CT data for node staging.

MATERIALS AND METHODS

Ninety-six patients who were referred for cervical lymph node staging with FDG-PET/CT before ultrasound were prospectively included. After routine ultrasound-guided fine-needle aspiration, all FDG-PET-positive nodes were marked on FDG-PET/CT, and real-time image fusing of ultrasound and FDG-PET/CT was performed using the electromagnetic navigation system PercuNav. Already-punctured nodes were confirmed to be PET-positive, and additional fused-ultrasound-guided fine-needle aspiration was performed in previously missed PET-positive nodes.

RESULTS

Of 96 patients, 87 (91%) patients had suspicious nodes requiring fine-needle aspiration cytology. Ultrasound-guided fine-needle aspiration was performed in 175 nodes. Cytology was inconclusive in 9/175 (5%) nodes, and 85/166 (51%) nodes were malignant. Target planning was performed in 201 PET-positive nodes; 195/201 (97%) of those nodes were fused successfully. Twenty of 175 ultrasound-guided fine-needle aspiration nodes turned out to be FDG-PET-negative, and 149/175 (85%) of the fused ultrasound-guided fine-needle aspiration nodes were confirmed to be FDG-PET-positive. Of 201 PET-positive nodes, 46 (23%) were additionally identified, and fused ultrasound-guided fine-needle aspiration was performed. Cytology was inconclusive in 4/46 nodes (9%), and 13/42 (31%) nodes were malignant.

CONCLUSIONS

Real-time ultrasound image fusion with FDG-PET-positive nodes is feasible in cervical lymph nodes, and fused ultrasound-guided fine-needle aspiration increases the number of malignant nodes detected.

A DUAL QUATERNION BASED METHOD FOR ESTIMATING MARGINS FOR PLANNING TARGET VOLUMES IN RADIOTHERAPY

This objective of this paper is to develop a dual quaternion based method for estimating target volumes in radiation therapy for head and neck cancer. Inaccuracies in radiation targeting are responsible for incidental exposure of healthy adjacent tissues, causing significant morbidity and mortality. This paper focuses on inaccuracies incurred when a tumor is displaced during treatment. To address this problem, the clinical target must be expanded to cover the region through which the tumor might move. The resulting expanded target is known as the Planning Target Volume (PTV). In the current practice, the rotational components of displacements are neglected, producing planning target volumes that either miss the true target motion or are larger than needed to cover the target path. By using the dual quaternion based kinematic formulation, this paper represents and captures both translational and rotational inaccuracies. It then presents a framework for calculating the PTV swept out by the target as it shifts within its range of translations and rotations.

External validation of International Prognostic Score for asymptomatic early stage chronic lymphocytic leukaemia and proposal of an alternative score

Most patients with chronic lymphocytic leukaemia (CLL) are nowadays diagnosed without any symptoms and do not require therapy. A prognostic score identifying patients within this large group who are at high risk of disease progression would be highly beneficial. The recently published International Prognostic Score for Early asymptomatic patients (IPS-E) uses combination of absolute lymphocyte count (ALC) >15 × 10⁹ /l, palpable lymphadenopathy, and unmutated immunoglobulin heavy-chain variable-region (IGHV) gene to predict the time to first-line therapy (TTFT). Patients at low, intermediate, and high risk had estimated 5-year TTFT of 8%, 28%, and 61%. We performed an external validation of the IPS-E score using an unselected, consecutive group of 130 Binet A patients. The 5-year TTFT was 11%, 36%, and 78% (C-statistic 0·74). Furthermore, we propose an alternative system (AIPS-E) using cytogenetic aberrations instead of palpable lymphadenopathy. This system yielded 5-year TTFT of 14%, 40%, and 72%. These results were externally validated in 388 Binet A patients from five Czech centres; the 5-year TTFT was 16%, 37%, and 80% (C-statistic 0·74). In conclusion, we have successfully validated the IPS-E score for patients with early stage CLL. In addition, we propose a modified scoring system, the AIPS-E, combining IGHV, fluorescence in situ hybridisation, and ALC.

Chapter 6 Non-Squamous Cell Causes of Cervical Lymphadenopathy

Cervical lymphadenopathy is a common indication for imaging evaluation of the neck. Besides metastatic squamous cell carcinoma of the head and neck, cervical lymphadenopathy can be due to many causes, with simple reactive lymphadenopathy on one end of the spectrum and malignant lymphadenopathy due to a distant infraclavicular primary, on the other end. A systematic approach to the cause of cervical lymphadenopathy, which includes pattern of lymph node enlargement, lymph node characteristics, systemic symptoms, and extranodal abnormalities, can be very useful in arriving at the correct diagnosis. In this article, various patterns of cervical lymphadenopathy due to non-squamous cell causes are discussed.

An update on the latest evidence for managing the clinically negative neck (cN0) in oral squamous cell carcinoma

The single most important prognostic indicator for survival in oral squamous cell carcinoma (OSCC) is the presence of lymph node metastases in the neck. While the treatment of the clinically node positive (cN+) neck is well established, the management of the clinically negative neck (cN0) is controversial. Various strategies have been advocated including close observation including regular ultrasound imaging, elective neck dissection and sentinel lymph node biopsy. Neck dissection surgery is not without potential morbidity with shoulder dysfunction being the main complication. A number of factors are associated with increased risk of neck node metastasis including primary tumour thickness and peri-neural invasion. A recent prospective randomised trial has found survival benefit following neck dissection even in patients with a cN0 neck at presentation. We discuss the latest evidence for managing the cN0 in OSCC and include our own experience on the role of neck dissection in certain cases.

Diffusion-weighted and PET/MR Imaging after Radiation Therapy for Malignant Head and Neck Tumors

Interpreting imaging studies of the irradiated neck constitutes a challenge because of radiation therapy-induced tissue alterations, the variable appearances of recurrent tumors, and functional and metabolic phenomena that mimic disease. Therefore, morphologic magnetic resonance (MR) imaging, diffusion-weighted (DW) imaging, positron emission tomography with computed tomography (PET/CT), and software fusion of PET and MR imaging data sets are increasingly used to facilitate diagnosis in clinical practice. Because MR imaging and PET often yield complementary information, PET/MR imaging holds promise to facilitate differentiation of tumor recurrence from radiation therapy-induced changes and complications. This review focuses on clinical applications of DW and PET/MR imaging in the irradiated neck and discusses the added value of multiparametric imaging to solve diagnostic dilemmas. Radiologists should understand key features of radiation therapy-induced tissue alterations and potential complications seen at DW and PET/MR imaging, including edema, fibrosis, scar tissue, soft-tissue necrosis, bone and cartilage necrosis, cranial nerve palsy, and radiation therapy-induced arteriosclerosis, brain necrosis, and thyroid disorders. DW and PET/MR imaging also play a complementary role in detection of residual and recurrent disease. Interpretation pitfalls due to technical, functional, and metabolic phenomena should be recognized and avoided. Familiarity with DW and PET/MR imaging features of expected findings, potential complications, and treatment failure after radiation therapy increases diagnostic confidence when interpreting images of the irradiated neck. Online supplemental material is available for this article.

Medical imaging in personalised medicine: a white paper of the research committee of the European Society of Radiology (ESR)

The future of medicine lies in early diagnosis and individually tailored treatments, a concept that has been designated 'personalised medicine' (PM), which aims to deliver the right treatment to the right patient at the right time. Medical imaging has always been personalised and is fundamental to almost all aspects of PM. It is instrumental in solving clinical differential diagnoses. Imaging procedures are tailored to the clinical problem and patient characteristics. Screening for preclinical disease is done with imaging. Stratification based on imaging biomarkers can help identify individuals suited for preventive intervention. Treatment decisions are based on the in vivo visualisation of the location and extent of an abnormality, as well as the loco-regional physiological, biochemical and biological processes using structural and molecular imaging. Image-guided biopsy provides relevant tissue specimens for genetic/molecular characterisation. In addition, radiogenomics relate imaging biomarkers to these genetic and molecular features. Furthermore, imaging is essential to patient-tailored therapy planning, therapy monitoring and follow-up of disease, as well as targeting non-invasive or minimally invasive treatments, especially with the rise of theranostics. Radiologists need to be prepared for this new paradigm as it will mean changes in training, clinical practice and in research. Key Points • Medical imaging is a key component in personalised medicine • Personalised prevention will rely on image-based screening programmes • Anatomical, functional and molecular imaging biomarkers affect decisions on the type and intensity of treatment • Treatment response assessment with imaging will improve personalised treatment • Image-based invasive intervention integrates personalised diagnosis and personalised treatment.

Imaging evaluation of lymphadenopathy and patterns of lymph node spread in head and neck cancer

Accurate and consistent characterization of metastatic cervical adenopathy is essential for the initial staging, treatment planning and surveillance of head and neck cancer patients. While enlarged superficial nodes may be clinically palpated, imaging allows identification of deeper adenopathy as well as clinically unsuspected pathology and thus imaging has become an integral part of the evaluation of most head and neck cancers patients. This review will focus on the evaluation of cervical adenopathy, summarizing the currently used nomenclature and imaging approach for determining cervical lymph node metastases in head and neck malignancies. The imaging-based classification, which has also been adopted by the American Joint Committee on Cancer, will be presented, the morphologic characteristics used to identify metastatic nodes will be reviewed and the typical nodal spread patterns of the major mucosal cancers of the head and neck will be examined.

Prognostic factors in advanced pharyngeal and oral cavity cancer; significance of multimodality imaging in terms of 7th edition of TNM

As with most cancers the prognosis in pharyngeal and oral cavity cancer largely depends on tumour stage. Physical examination, including endoscopy should be combined with technical radiologic imaging to record the precise extent of tumour. The TNM staging system of the head and neck region is, in fact, an anatomic staging system that describes the anatomic extent of the primary tumour as well as the involvement of regional lymph nodes and distant metastases. Modifications in the TNM staging system should consider not only the expert opinions and published reports in the literature but the technical advances in technology for improved assessment of tumour extent and the shifting paradigms in therapeutic strategies. “T” stage of the tumour is defined by its size, the depth of the invasion and the involvement of vital structures. In the 7th edition of TNM classification, for stage T4 tumors (larger than 4 cm), subcategories a and b were introduced to indicate the involvement of vital structures and their suitability for surgical resection (except for nasopharynx cancer). Nodal metastasis is the most important predictor of outcome for squamous cell cancer of the head and neck.

Better and more reliable methods of pretreatment tumour assessment are therefore crucial to ensure that the clinical assessment of tumor approximates its actual pathologic extent.

CT and MRI are both useful for assessing extensions of pharyngeal- and oral cavity cancer in advanced stage. MRI is superior in visualizing most primary tumour sites.

Tumor markers in fine-needle aspiration washout for cervical lymphadenopathy in patients with known malignancy: preliminary study

OBJECTIVE

The purposes of our study were to assess whether tumor marker concentration in fine-needle aspiration (FNA) washout from cervical lymph nodes (LNs) differs between metastatic and nonmetastatic LNs and whether tumor marker concentrations in FNA washout can contribute to the diagnosis of metastatic LNs.

SUBJECTS AND METHODS

Ultrasound-guided FNA was performed for 157 neck nodes in 157 patients, including 136 patients with known malignancy (28 breast, 34 lung, 41 head and neck, seven esophagus, nine cervix, 10 gastrointestinal [GI] tract, and seven ovary cancers) and 21 patients without known malignancy (control group). Immediately after an FNA cytology specimen was obtained, the needle was rinsed with 1 mL of normal saline solution, and variable tumor marker concentrations were measured in the washout: carcinoembryonic antigen (CEA) and cancer antigen (CA) 15-3 for breast; CEA and cytokeratin 19 fragment for lung; squamous cell antigen for head and neck, esophagus, and cervix; CEA and CA 19-9 for GI; CA 125 for ovarian cancer; and all the tumor marker concentrations for the control group. The tumor marker concentration was compared between the metastatic and nonmetastatic LNs in the control group and between the metastatic and nonmetastatic LNs in the known malignancy group, according to the known malignancy.

RESULTS

At final diagnosis, 104 LNs were metastatic and 53 were nonmetastatic (including 21 LNs in the control group). The tumor marker concentrations of cases with negative or nondiagnostic cytologic results were evaluated. The sensitivity of FNA cytology alone was compared with the combined sensitivity of FNA cytology and tumor marker concentration. Metastatic LNs had higher corresponding FNA tumor marker concentrations than did nonmetastatic LNs in both the control and known malignancy groups (p < 0.05), except for CA 19-9 in GI cancer. Eight of 10 cases (80%) with negative or nondiagnostic cytologic results but metastatic LNs at final diagnosis showed elevated tumor marker concentrations. The sensitivity of FNA cytology (90.4%) increased to 98.1% when combined with tumor marker concentration (p < 0.05). Tumor marker concentrations in FNA washout with cervical metastatic LNs were elevated in comparison with those of nonmetastatic LNs.

CONCLUSION

Evaluation of tumor marker concentrations in FNA washout could improve the detection of metastatic LNs in patients with known malignancy.

Advanced clinical usefulness of ultrasonography for diseases in oral and maxillofacial regions

Various kinds of diseases may be found in the oral and maxillofacial regions and various modalities may be applied for their diagnosis, including intra-oral radiography, panoramic radiography, ultrasonography, computed tomography, magnetic resonance imaging, and nuclear medicine methods such as positron emission tomography. Of these modalities, ultrasound imaging is easy to use for the detection of noninvasive and soft tissue-related diseases. Doppler ultrasound images taken in the B-mode can provide vascular information associated with the morphology of soft tissues. Thus, ultrasound imaging plays an important role in confirming the diagnosis of many kinds of diseases in such oral and maxillofacial regions as the tongue, lymph nodes, salivary glands, and masticatory muscles. In the present article, we introduce three new applications of ultrasonography: guided fine-needle aspiration, measurement of tongue cancer thickness, and diagnosis of metastasis to cervical lymph nodes.

Head and neck squamous cell carcinoma: value of diffusion-weighted MR imaging for nodal staging

PURPOSE

To evaluate diffusion-weighted (DW) magnetic resonance (MR) imaging, as compared with turbo spin-echo MR imaging, for the detection of nodal metastases in head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

The study was approved by the ethics committee, and patients gave written informed consent. Before undergoing surgery, 33 consecutive patients underwent 1.5-T MR imaging, including DW imaging performed with a wide range of b values (0-1000 sec/mm(2)). The apparent diffusion coefficients (ADCs) of lymph nodes 4 mm or greater in short-axis diameter depicted on images obtained with b values of 0 and 1000 sec/mm(2) were calculated. After topographic correlation, the lymph nodes were evaluated microscopically with prekeratin immunostaining. The optimal ADC thresholds for discriminating between metastatic and benign lymph nodes were determined. The sensitivity, specificity, and accuracy of DW imaging were calculated separately-on per-lymph-node and per-neck-level bases-for all lymph nodes and for supracentimeter and subcentimeter lymph nodes and were compared with corresponding turbo spin-echo MR imaging values.

RESULTS

Correlation of histopathologic and radiologic findings was possible for 301 lymph nodes. The ADC derived from the signal intensity averaged across images obtained with b values of 0 and 1000 sec/mm(2) (ADC(b0-1000)) was 1.19 x 10(-3) mm(2)/sec +/- 0.22 (standard deviation) for benign lymph nodes and 0.85 x 10(-3) mm(2)/sec +/- 0.27 for malignant lymph nodes (P < .0001). With an optimal ADC(b0-1000) threshold of 0.94 x 10(-3) mm(2)/sec, 84% sensitivity, 94% specificity, and 91% accuracy for differentiation of malignant versus benign status of each lymph node and 94% sensitivity, 97% specificity, and 97% accuracy for differentiation at each neck level were achieved. Compared with turbo spin-echo imaging, DW imaging had higher sensitivity (76% vs 7%) but slightly lower specificity (94.0% vs 99.5%) for detection of subcentimeter nodal metastases.

CONCLUSION

DW imaging performed with ADC(b0-1000) values had higher accuracy than turbo spin-echo MR imaging in nodal staging, providing added value in the detection of subcentimeter nodal metastases.

Management of the N0 neck in oral squamous cell carcinoma

Oral squamous cell carcinoma (SCC) has an unpredictable capacity to metastasize to the neck, an event that dramatically worsens prognosis. Metastasis occurs even in earlier stages when no neck lymph node involvement is clinically detectable (N0). Management of the N0 neck, namely when and how to electively treat, has been debated extensively. This article presents the controversies surrounding management of the N0 neck, and the benefits and pitfalls of different approaches used in evaluation and treatment. As current methods of assessing the risk for occult metastasis are insufficiently accurate and prone to underestimation of actual risk, and because selective neck dissection (SND) is an effective treatment and has minimal long-term detriment to quality of life, the authors believe that all patients who have oral SCC, excluding lip SCC, should be prescribed elective treatment of the neck lymphatics. However, this opinion remains controversial. Because of the morbidity of radiation therapy and because treatment of the primary tumor is surgical, elective neck dissection is the preferred treatment. In deciding the extent of the neck dissection, several retrospective studies and one randomized clinical trial have shown SND of levels I through III to be highly efficacious.

[Tumors of the oropharynx and oral cavity: MR, CT, PET-CT imaging]

Pretherapeutic imaging plays a central role in the management of tumors of the oropharynx and oral cavity. MR and, to a lesser extent, CT and F-18 FDG PET-CT are the imaging modalities of choice for pretherapeutic work-up of these lesions. Imaging protocols should be simple and reproducible, and should provide the key elements for treatment planning.

Head and neck cancer: how imaging predicts treatment outcome

Sophisticated imaging methods, such as computed tomography, magnetic resonance imaging and positron emission tomography, play an increasingly important role in the management of head and neck cancer. Pretreatment imaging findings have predictive value for patient outcome, independently from the currently used TNM classification, and may be used to tailor treatment to the individual patient. Based on per-treatment imaging, individualised replanning during radiotherapy may ameliorate tumour control rates and reduce toxic effects to normal tissues. Early posttreatment imaging studies contain important prognostic information, and allow selection of patients for further treatment or watchful waiting.