Neck Imaging Reporting And Data System Research Articles

Posttreatment Head and Neck Cancer Imaging: Anatomic Considerations Based on Cancer Subsites.

Posttreatment imaging surveillance of head and neck cancer is challenging owing to complex anatomic subsites and diverse treatment modalities. Early detection of residual disease or recurrence through surveillance imaging is crucial for devising optimal treatment strategies. Posttreatment imaging surveillance is performed using CT, fluorine 18-fluorodeoxyglucose PET/CT, and MRI. Radiologists should be familiar with postoperative imaging findings that can vary depending on surgical procedures and reconstruction methods that are used, which is dictated by the primary subsite and extent of the tumor. Morphologic changes in normal structures or denervation of muscles within the musculocutaneous flap may mimic recurrent tumors. Recurrence is more likely to occur at the resection margin, margin of the reconstructed flap, and deep sites that are difficult to access surgically. Radiation therapy also has a varying dose distribution depending on the primary site, resulting in various posttreatment changes. Normal tissues are affected by radiation, with edema and inflammation occurring in the early stages and fibrosis in the late stages. Distinguishing scar tissue from residual tumor becomes necessary, as radiation therapy may leave behind residual scar tissue. Local recurrence should be carefully evaluated within areas where these postradiation changes occur. Head and Neck Imaging Reporting and Data System (NI-RADS) is a standardized reporting and risk classification system with guidance for subsequent management. Familiarity with NI-RADS has implications for establishing surveillance protocols, interpreting posttreatment images, and management decisions. Knowledge of posttreatment imaging characteristics of each subsite of head and neck cancers and the areas prone to recurrence empowers radiologists to detect recurrences at early stages. ©RSNA, 2024 Test Your Knowledge questions in the supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

Definitive Chemoradiation Treatment Response Evaluation Using NI-RADS and ctHPVDNA for HPV-Associated Oropharyngeal Squamous Cell Carcinoma

To compare the evaluation of treatment response among patients with human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) treated with definitive (chemo)radiotherapy (CRT). Patients with locally advanced HPV-associated OPSCC treated with definitive radiotherapy (RT) or CRT from 2019 to 2022 at a single institution were reviewed. Patients underwent standard 3-month post-CRT positron emission tomography/computed tomography (PET/CT) scan with or without contrast enhanced CT (CECT) of the head and neck. Plasma circulating tumor HPV DNA (ctHPVDNA) was collected from 2-8 months post-CRT. Equivocal findings on post-CRT imaging prompted repeat evaluation. Imaging response was assessed via NI-RADS (Neck Imaging Reporting and Data System) risk classification and independently reviewed by two board certified radiologists, both blinded to outcomes and ctHPVDNA values. Our cohort of 52 patients included: 87% males; median age 61.5; 63% never smokers, 31% former smokers, 6% current smokers; 44% tonsil primary, 46% base of tongue; 4% T0, 25% T1, 40% T2, 12% T3, 17% T4; 6% N0, 15% N1, 2% N2a, 44% N2b, 25% N2c, 8% N3 (AJCC 7th edition). Concurrent systemic therapy was received in 90%. During this period 71 PET/CTs and 15 CECTs were reviewed for treatment response evaluation; 44% (23/52) patients required additional imaging for equivocal findings; 62 ctHPVDNA blood samples were co-analyzed for treatment evaluation. The highest risk classification score between mucosa, primary, and/or neck site was: 42% NI-RADS 1, 48% NI-RADS 2, and 10% NI-RADS 3. Only patients with locoregional disease recurrence/progression were included for evaluation comparison between imaging and circulating biomarkers. No cancer events occurred without imaging and/or ctHPVDNA detection. Patients with NI-RADS score ≥2 during first post-CRT imaging evaluation more frequently underwent additional imaging (70% vs 30%, p<0.001). NI-RADS risk classification suggested 5 locoregional events (2 true positives, 3 false positives) resulting in 100% sensitivity, 94% specificity, 40% positive predictive value (PPV), and 100% negative predictive value (NPV). Circulating tumor HPV-DNA identified 2 locoregional events (2 true positives, 0 false positives) resulting in 100% sensitivity, 100% specificity, 100% PPV, and 100% NPV. Salvage operations were performed in 2 of 3 patients with false positive disease by NI-RADS classification without any evidence of cancer on final pathology. While limited by the small number of recurrence events in this cohort, ctHPVDNA for HPV-associated OPSCC in conjunction with post-treatment imaging evaluation may limit the need for repeat imaging and unwarranted salvage operations that increase patient worry, morbidity, and financial toxicity. Additional prospective study is warranted.

Response assessment of post-treatment head and neck cancers to determine further management using NI-RADS (Neck Imaging Reporting and Data System): a subgroup analysis of a randomized controlled trial.

Interpreting complex post-treatment changes in head and neck cancer (HNC) is challenging with further added perplexity due to variable interobserver interpretation and hence evolved the NI-RADS lexicon. We evaluated the accuracy of NI-RADS in predicting disease status on 1st post-treatment follow-up CECT in a homogenous cohort of those who received only chemoradiation. Retrospective analysis of imaging was done for LASHNC patients who received radical chemoradiation in an open-label, investigator-initiated, phase 3 randomized trial (2012-2018) randomly assigned to either radical radiotherapy with concurrent weekly cisplatin (CRT) or CRT with the same schedule plus weekly nimotuzumab (NCRT). 536 patients were accrued, and 74 patients who did not undergo PET/CECT after 8 weeks post-CRT were excluded. After assessing 462 patients for eligibility to allocate NI-RADS at primary and node sites, 435 cases fell in the Primary disease cohort and 412 cases in the Node disease cohort. We evaluated sensitivity, disease prevalence, the positive and negative predictive value of the NI-RADS lexicon, and accuracy, which were expressed as percentages. We also prepared flow charts to determine concordance with allocated NI-RADS category and established accuracy with which it can identify disease status. Out of 435 primary disease cohort, 92%, 55%, 48%,70% were concordant and had 100%, 72%, 70%, 82% accuracy in NI-RADS1 (n=12), NI-RADS2 (n=261), NIRADS3 (n=105), and NI-RADS 4 (n=60) respectively. Out of 412 nodes disease cohort, 95%, 90%, 48%, 70%were concordant and had 92%, 97%, 90%, 67% accuracy in NI-RADS1 (n=57), NI-RADS2 (n=255), NI-RADS3 (n=105) and NI-RADS4 (n=60) respectively. % concordance of PET/CT and CECT across all primary and node disease cohorts revealed that PET/CT was 91% concordant in primary NI-RADS2 as compared to 55% concordance of CECT whereas concordance of CECT was better with 57% in primary NI-RADS3 cohort as compared to PET/CT concordance of 41%. The accuracy with which the NI-RADS lexicon performed in our study at node sites was better than that at the primary site. There is a great scope of research to understand if CECT performs better over clinical disease status in NI-RADS 3 and 4 categories. Further research should be carried out to understand if PET/CECT can be used for close interval follow-up in stage III/IV NI-RADS 2 cases.

Performance of Neck Imaging Reporting and Data System (NI-RADS) for Diagnosis of Recurrence of Head and Neck Squamous Cell Carcinoma: A Systematic Review and Meta-analysis.

The Neck Imaging Reporting and Data System (NI-RADS) is a reporting template used in head and neck cancer posttreatment follow-up imaging. Our aim was to evaluate the pooled detection rates of the recurrence of head and neck squamous cell carcinoma based on each NI-RADS category and to compare the diagnostic accuracy between NI-RADS 2 and 3 cutoffs. The MEDLINE, Scopus, and EMBASE databases were searched. This systematic review identified 7 studies with a total of 694 patients (1233 lesions) that were eligible for the meta-analysis. The meta-analysis of pooled recurrence detection rate estimates for each NI-RADS category and the diagnostic accuracy of recurrence with NI-RADS 3 or 2 as the cutoff was performed. The estimated recurrence rates in each category for primary lesions were 74.4% for NI-RADS 3, 29.0% for NI-RADS 2, and 4.2% for NI-RADS 1. The estimated recurrence rates in each category for cervical lymph nodes were 73.3% for NI-RADS 3, 14.3% for NI-RADS 2, and 3.5% for NI-RADS 1. The area under the curve of the summary receiver operating characteristic for recurrence detection with NI-RADS 3 as the cutoff was 0.887 and 0.983, respectively, higher than 0.869 and 0.919 for the primary sites and cervical lymph nodes, respectively, with NI-RADS 2 as the cutoff. Given the heterogeneity of the data of the studies, the conclusions should be interpreted with caution. This meta-analysis revealed estimated recurrence rates for each NI-RADS category for primary lesions and cervical lymph nodes and showed that NI-RADS 3 has a high diagnostic performance for detecting recurrence.

Assessment of head and neck-imaging reporting and data system using fluro-deoxy-glucose-positron emission tomography/computerized tomography scan imaging of recurrence of head and neck tumors

BackgroundWorldwide, there are more than 550,000 new instances of head and neck cancer per year, with over 300,000 fatalities. Among the Middle Eastern nations, Egypt had one of the highest overall incidence rates of oral cavity and pharynx cancer (5.5/105). A consistent reporting form for head and neck cancer monitoring provides many crucial functions, including directing patient care with simply explained numerical scores for tumor recurrence suspicion levels. The Neck-Imaging Reporting and Data System (NI-RADS) assigns a numerical grade, from 0 to 4, where 0 represents incomplete, 1 represents no evidence of local recurrence (primary site) or adenopathy (neck), 2 represents low suspicion, 3 represents high suspicion, and 4 represents definite recurrence. Our aim was to improve the management outcome for patients liable to recurrence of head and neck cancers post-treatment with radio or chemotherapy using Neck-imaging Reporting and Data System (NI-RADS) after imaging with Fluro-Deoxy-Glucose-Positron Emission Tomography/Computed Tomography Scan (FDG-PET/CT Scan).Materials and methodsThe study setting was done at our institution and the type of study was combined prospective and retrospective study for 24 months from June 2020 to June 2022. The study population included 71 scans for 55 patients aged between 18 and 70 years, who had suffered from head and neck cancer and underwent treatment by chemotherapy or radiotherapy to follow up on their cases and determine recurrence or resolution of tumors.ResultsThe results demonstrated the classification of tumor findings according to the degree of malignancy with 16.9% of scans were diagnosed as low pathological grade, 60.6% were diagnosed as intermediate pathological grade and 22.5% were diagnosed as high pathological grade. The initial tumor subsites in our study were as follow: the oral cavity with its different subsites represented the largest group constituting 11 cases (20%) of the total cases, and the larynx and vocal cords came next and constituted 10 cases (18.2%) of the total scans, nasopharynx constituted 9 cases (16.4%) of the cases. According to application of NI-RADS score, cases were classified as 17 cases NI-RADS (1), representing 30.1% of cases, 9 cases NI-RADS (2), representing 16.36% of cases, 18 cases NI-RADS (3), representing 32.7% of cases and 11 cases NI-RADS (4) representing 20% of cases. Percentage of recurrence in NI-RADS (1) was 1/17 representing 5.9%, in NI-RADS (2) was 2/9 representing 22.2%, in NI-RADS (3) was 12/18 representing 66.66%, in NI-RADS (4) was 10/11 representing 90.9% with total recurrence 25/55 cases representing 45.45%.ConclusionsNeck-Imaging Reporting and Data System using FDG PET/CT Scan imaging for assessment of recurrence of head and neck tumors was a choice of relatively high sensitivity and specificity for improvement of significant results and guiding the clinician to the proper management strategy for the patients as well as organizing a strategy for follow-up of cases according to their score of NI-RADS.

Diagnostic Performance of Response Assessment FDG-PET/CECT in HNSCC Treated With Definitive Radio(chemo)therapy Using NI-RADS.

To assess the diagnostic performance of response assessment 18F-fluorodeoxyglucose positron emission tomography/contrast-enhanced computed tomography (FDG-PET/CECT) following definitive radio(chemo)therapy in head and neck squamous cell carcinoma (HNSCC) using Neck Imaging Reporting and Data System (NI-RADS). A retrospective analysis from a prospectively maintained dataset. Tertiary-care comprehensive cancer center in a low-middle-income country. Adults with newly diagnosed, biopsy-proven, nonmetastatic HNSCC treated with definitive radio(chemo)therapy were included. Posttreatment response assessment FDG-PET/CECT scans were retrospectively assigned NI-RADS categories (1-3) for the primary site, neck, and both sites combined. Locoregional recurrence occurring within 2-years was defined as the event of interest. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy were calculated. Locoregional control stratified by NI-RADS categories was computed with the Kaplan-Meier method and compared using the log-rank test. Posttreatment FDG-PET/CECT scans were available in 190 patients constituting the present study cohort. Sensitivity, specificity, PPV, NPV, and overall accuracy of the NI-RADS template for the primary site was 73.5%, 81.4%, 46.3%, 93.4%, and 80.0%, respectively. Similar metrics for the neck were 72.7%, 87.5%, 43.2%, 96.1%, and 85.8%, respectively. Combining primary site and neck, the corresponding metrics of diagnostic accuracy were 84.4%, 69.7%, 46.3%, 93.5%, and 73.2%, respectively. At a median follow-up of 40 months, Kaplan-Meier estimates of 2-year locoregional control were significantly higher for NI-RADS category 1 (94.2%) compared to NI-RADS category 2 (69.4%) and category 3 (20.4%), respectively (stratified log-rank p < .0001). FDG-PET/CECT using the NI-RADS template is associated with good diagnostic performance and prognostic utility in HNSCC treated with definitive radio(chemo)therapy.

Neck Imaging Reporting and Data System: More Than Just a Template.

The Neck Imaging Reporting and Data System (NI-RADS) is a guide developed and introduced in 2017 by head and neck radiologists who worked in an academic radiology department. Based on the Breast Imaging Reporting and Data System, the initial goals of NI-RADS were to make posttreatment head and neck cancer imaging dictations more succinct and efficient, guide treating physicians in the next appropriate steps when recurrence was suspected, and encourage institutional and national research. NI-RADS is more than a dictation template, and it is best instituted after a head and neck imaging practice is established. We support the use of NI-RADS once a radiologist understands the nuances of head and neck cancer, including the biology, common subsites involved, essentials of tumor staging, common posttreatment benign imaging appearances, and subtleties of recurrent disease.

Performance of the Neck Imaging Reporting and Data System as applied by general neuroradiologists to predict recurrence of head and neck cancers.

The Neck Imaging Reporting and Data System (NI-RADS) is used to assess imaging after head and neck cancer treatment. We evaluated NI-RADS with general neuroradiologists rather than with head and neck subspecialists. Computed tomography and magnetic resonance imaging examinations with/without positron emission tomography from May 2018 to September 2020 were retrospectively identified. NI-RADS scores at the primary site and lymph nodes were provided by 21 neuroradiologists. Recurrence status was based on clinical and imaging findings. Area under the curve (AUC) was used to assess accuracy. We assessed 608 scans from 464 patients. For NI-RADS categories 1, 2, and 3, primary site recurrence rates were 5%, 29%, and 65% with AUC of 0.765, while lymph node recurrence rates were 3%, 10%, and 80% with AUC of 0.820. NI-RADS as used by general neuroradiologists is effective in separating head and neck cancers into discrete categories for predicting recurrent disease.

Adding MR Diffusion Imaging and T2 Signal Intensity to Neck Imaging Reporting and Data System Categories 2 and 3 in Primary Sites of Postsurgical Oral Cavity Carcinoma Provides Incremental Diagnostic Value.

The NI-RADS lexicon doesn't use ADC parameters and T2 weighted signal for ascribing categories. We explored ADC, DWI, and T2WI to examine the diagnostic accuracy in primary sites of postsurgical oral cavity carcinoma in the Neck Imaging Reporting and Data System (NI-RADS) categories 2 and 3. We performed a retrospective analysis in clinically asymptomatic post-surgically treated patients with oral cavity squamous cell carcinoma who underwent contrast-enhanced MRI between January 2013 and January 2016. Histopathology and follow-up imaging were used to ascertain the presence or absence of malignancy in subjects with "new enhancing lesions," which were interpreted according to the NI-RADS lexicon by experienced readers, including NI-RADS 2 and 3 lesions in the primary site. NI-RADS that included T2WI and DWI (referred to as NI-RADS A) and ADC (using the best cutoff from receiver operating characteristic curve analysis, NI-RADS B) was documented in an Excel sheet to up- or downgrade existing classic American College of Radiology NI-RADS and calculate diagnostic accuracy. Sixty-one malignant and 23 benign lesions included in the study were assigned American College of Radiology NI-RADS 2 (n = 33) and NI-RADS 3 (n = 51) categories. The recurrence rate was 90% (46/51) for NI-RADS three, 45% (15/33) for NI-RADS 2, and 73% (61/84) overall. T2WI signal morphology was intermediate in 45 subjects (53.5%) and restricted DWI in 54 (64.2%). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the American College of Radiology NI-RADS were the following: NI-RADS (75.4%, 78.3%, 90.1%, 54.5%, and 76.1%); NI-RADS A (79.1%, 81.2%, 91.9%, 59.1%, and 79.6%); and NI-RADS B (88.9%, 72.7%, 91.4%, 66.7%, and 85.1%), respectively. Adding MR imaging diagnostic characteristics like T2WI, DWI, and ADC to the American College of Radiology NI-RADS improved diagnostic accuracy and sensitivity.

Performance of NI-RADS on CECT Alone to Predict Recurrent Head and Neck Squamous Cell Carcinoma after Chemoradiotherapy: Added Value of RECIST 1.1.

Background The Head and Neck Imaging Reporting and Data System (NI-RADS) is a standardized reporting format for the categorization of the degree of suspicion for recurrent head and neck malignancies on positron emission tomography/computed tomography. Purpose The purpose of our study was to analyze the efficacy of the NI-RADS rating scale and criteria for contrast-enhanced computed tomography (CECT) alone in predicting the local and regional recurrence of malignancies after chemoradiotherapy. Material and Methods CECT of the patients with head and neck cancers receiving radiotherapy and concurrent chemotherapy as a primary treatment was obtained 3 months after the completion of radiotherapy and NI-RADS scoring was done using components of Response Evaluation Criteria in Solid Tumors (RECIST 1.1) criteria. Their management was guided according to the recommendations based on their NI-RADS score. Results Thirty patients with squamous cell carcinoma of the neck were included in this study. The positive or negative status of the recurrent disease was based on biopsy results or follow-up protocol as recommended in NI-RADS rating scale. Fifteen patients had path proven recurrence at the primary tumor site. For primary tumor site, disease persistence rates of 4% for NI-RADS 1, 24% for NI-RADS 2, and 80% for NI-RADS 3 scores were seen. Five patients had recurrent lymph nodal disease. For lymph nodal assessment, NI-RADS categories 1, 2, and 3 revealed nodal disease recurrence rates of 5.3, 25, and 66.7%, respectively. Conclusion CECT alone may be used to assign the NI-RADS rating scale using RECIST 1.1 criteria to predict the presence or absence of recurrent tumor in patients with neck malignancies.

Neck Imaging Reporting and Data System Category 3 on Surveillance Computed Tomography: Incidence, Biopsy Rate, and Predictive Performance in Head and Neck Squamous Cell Carcinoma.

Neck Imaging Reporting and Data System (NI-RADS) is a radiology reporting system for head and neck cancer surveillance. Imaging findings of high suspicion for recurrence are assigned Category 3 and recommended for "Biopsy, if clinically indicated." After implementing NI-RADS for surveillance neck computed tomography (CT), our objectives are to determine the incidence of squamous cell carcinoma (SCC) Category 3 lesions in the year post-implementation, the associated biopsy rate, and the positive predictive value of NI-RADS 3 for SCC recurrence. Retrospective cohort study. Neck CTs reported with NI-RADS between February 2020 and February 2021 were reviewed to identify patients undergoing surveillance for SCC assigned NI-RADS 3. Cancer recurrence, defined as positive biopsy result or treatment of clinically determined recurrence, was determined by electronic medical record review. During the study period, 580 neck CTs were reported with NI-RADS, of which 39 (7%) CTs obtained in 37 unique patients (28 male, 9 female, mean age 66.6 years) formed the study cohort. Biopsies were obtained in 23 lesions (45%), of which 17 (74%) were positive for recurrent SCC. One nondiagnostic biopsy was clinically determined to represent recurrence. Of 28 (55%) lesions not biopsied, 18 (64%) were ultimately treated as clinically determined recurrence. Thus, among 51 individual NI-RADS 3 lesions (32 primary, 19 neck), 36 (71%) represented recurrence. The incidence of NI-RADS 3 lesions in our cohort was 7%. The biopsy rate was 45%, and the overall positive predictive value of NI-RADS 3 for recurrent SCC was 71%. Category 3 lesions are associated with substantial SCC recurrence risk and should be managed accordingly. 4 Laryngoscope, 132:1792-1797, 2022.

Initial Referring Physician and Radiologist Experience with Neck Imaging Reporting and Data System.

Neck Imaging Reporting and Data System (NI-RADS) is a radiology reporting system developed for head and neck cancer surveillance imaging, using standardized terminology, numeric levels of suspicion, and linked management recommendations. Through a multidisciplinary, interdepartmental quality improvement initiative, we implemented NI-RADS for the reporting of head and neck cancer surveillance CT. Our objective is to summarize our initial experience from the standpoints of head and neck cancer providers and radiologists. Quality improvement study. Before and 3 months post-implementation, surveys were offered to referring physicians (n=21 pre-adoption; 22 post-adoption) and radiologists (n=17 pre- and post-adoption). NI-RADS utilization was assessed over time. Survey response rates were 62% (13/21) and 73% (16/22) for referring physicians pre- and post-adoption, respectively, and 94% (16/17) for radiologists pre- and post-adoption. Among post-adoption provider respondents, 100% (16/16) strongly agreed or agreed with "I want our radiologists to continue using NI-RADS," "The NI-RADS numerical rating of radiologic suspicion is helpful," and "The language and style of NI-RADS neck CT reports are clear and understandable." Among radiologist respondents, 88% (14/16) strongly agreed or agreed with "NI-RADS improves consistency among our radiologists in the reporting of surveillance neck CTs." Radiologist NI-RADS utilization increased over time (46% month 1; 72% month 3). Most referring physicians and radiologists preferred NI-RADS. Head and neck cancer providers indicated that NI-RADS reports are clear, understandable, direct, and helpful in guiding clinical management. Radiologists indicated that NI-RADS improves radiologist consistency in the reporting of surveillance neck CT, and radiologists increasingly used NI-RADS over time. 4 Laryngoscope, 132:349-355, 2022.

Impact of double reading on NI-RADS diagnostic accuracy in reporting oral squamous cell carcinoma surveillance imaging - a single-center study.

The Neck Imaging Reporting and Data System (NI-RADS) is an increasingly utilized risk stratification tool for imaging surveillance after treatment for head and neck cancer. This study aims to measure the impact of supervision by subspecialized radiologists on diagnostic accuracy of NI-RADS when initial reading is performed by residents. 150 CT and MRI datasets were initially read by two trained residents, and then supervised by two subspecialized radiologists. Recurrence rates by NI-RADS category were calculated, and receiver operating characteristic (ROC) curves were plotted. After dichotomization of the NI-RADS system (category 1 vs categories 2 + 3+4 and categories 1 + 2 vs 3 + 4), sensitivity, specificity, positive and negative predictive value were calculated. 26% of the reports were modified by the supervising radiologists. Area under the curve of ROC plots values of the supervision session were higher than those of the initial reading session for both the primary site (0.89 vs 0.86) and the neck (0.94 vs 0.91), but the difference was not statistically significant. For dichotomized NI-RADS category assignments, differences between the initial reading and the supervision session were statistically significant regarding specificity and PPV for the primary site (1 + 2 vs 3 + 4 and 1 vs 2 + 3+4) or even for both sites combined (1 vs 2 + 3+4). NI-RADS enables trained resident radiologists to report surveillance imaging in patients with treated oral squamous cell carcinoma with high discriminatory power. Additional supervision by a subspecialized head and neck radiologist particularly improves specificity of radiological reports.

Interrater Reliability of NI-RADS on Posttreatment PET/Contrast-enhanced CT Scans in Head and Neck Squamous Cell Carcinoma.

Purpose To evaluate the interrater reliability among radiologists examining posttreatment head and neck squamous cell carcinoma (HNSCC) fluorodeoxyglucose PET/contrast-enhanced CT (CECT) scans using Neck Imaging Reporting and Data System (NI-RADS). Materials and Methods In this retrospective study, images in 80 patients with HNSCC who underwent posttreatment surveillance PET/CECT and immediate prior comparison CECT or PET/CECT (from June 2014 to July 2016) were uploaded to the American College of Radiology's cloud-based website, Cortex. Eight radiologists from seven institutions with variable NI-RADS experience independently evaluated each case and assigned an appropriate prose description and NI-RADS category for the primary site and the neck site. Five of these individuals were experienced readers (> 5 years of experience), and three were novices (< 5 years of experience). In total, 640 lexicon-based and NI-RADS categories were assigned to lesions among the 80 included patients by the eight radiologists. Light generalization of Cohen κ for interrater reliability was performed. Results Of the 80 included patients (mean age, 63 years ± 10 [standard deviation]), there were 58 men (73%); 60 patients had stage IV HNSCC (75%), and the most common tumor location was oropharynx (n = 32; 40%). Light κ for lexicon was 0.30 (95% CI: 0.23, 0.36) at the primary site and 0.31 (95% CI: 0.24, 0.37) at the neck site. Light κ for NI-RADS category was 0.55 (95% CI: 0.46, 0.63) at the primary site and 0.60 (95% CI: 0.48, 0.69) at the neck site. Percent agreement between lexicon and correlative NI-RADS category was 84.4% (540 of 640) at the primary site and 92.6% (593 of 640) at the neck site. There was no significant difference in interobserver agreement among the experienced versus novice raters. Conclusion Moderate agreement was achieved among eight radiologists using NI-RADS at posttreatment HNSCC surveillance imaging. Keywords: CT, PET/CT, Head/Neck, Neck, Neoplasms-Primary, Observer Performance Supplemental material is available for this article. © RSNA, 2021.

MRI Posttreatment Surveillance for Head and Neck Squamous Cell Carcinoma: Proposed MR NI-RADS Criteria.

The current Neck Imaging Reporting and Data System (NI-RADS) criteria were designed for contrast-enhanced CT with or without PET. Prior studies have revealed the capability of DWI and T2 signal intensity in distinguishing locoregional tumor residual and recurrence from posttreatment benign findings in head and neck cancers. We aimed to propose MR imaging NI-RADS criteria by adding diffusion criteria and T2 signal intensity to the American College of Radiology NI-RADS template. This retrospective study included 69 patients with head and neck squamous cell carcinoma (HNSCC) who underwent posttreatment contrast-enhanced MRI imaging surveillance using a 1.5T scanner. The scans were interpreted by 2 neuroradiologists. Image analysis assessed the primary tumor site using the current American College of Radiology NI-RADS morphologic lexicon (mainly designed for contrast-enhanced CT with or without PET). NI-RADS rescoring was then performed based on our proposed criteria using T2 signal and diffusion features. The reference standard was a defined set of criteria, including clinical and imaging follow-up and pathologic assessment. Imaging assessment of treated HNSCC at the primary tumor site using T2 signal intensity and diffusion features as modifying rules to NI-RADS showed higher sensitivity, specificity, positive predictive value, negative predictive value, and accuracy (92.3%, 90.7%, 85.7%, 95.1%, and 91.3%, respectively) compared with the current NI-RADS lexicon alone (84.6%, 81.4%, 73.3%, 89.8%, and 82.6%, respectively). The addition of diffusion features and T2 signal to the American College of Radiology NI-RADS criteria for the primary tumor site enhances the specificity, sensitivity, positive predictive value, negative predictive value, and NI-RADS accuracy.

Reliability of NI-RADS criteria in the interpretation of contrast-enhanced magnetic resonance imaging considering the potential role of diffusion-weighted imaging

ObjectivesTo assess inter- and intrareader agreement of the Neck Imaging Reporting and Data System (NI-RADS) used in contrast-enhanced magnetic resonance imaging (MRI) including analysis of diffusion-weighted imaging (DWI), which is currently not part of the NI-RADS criteria.MethodsThis retrospective study included anonymized surveillance contrast-enhanced MRI datasets of 104 patients treated for different head and neck cancers. Three radiologists experienced in head and neck imaging reported findings for the primary site and the neck using NI-RADS criteria in a first step and evaluated DWI sequences for the primary site in a second step. Thirty randomly selected imaging datasets were again presented to the readers. Kappa statistics and observed agreement (Ao) were calculated.ResultsInterreader agreement across all MRI datasets was moderate (κFleiss = 0.53) for NI-RADS categories assigned to the primary site, substantial for NI-RADS categories of the neck (κFleiss = 0.67), and almost perfect for DWI of the primary site (κFleiss = 0.83). Interreader agreement for the primary site was particularly low in cases of cancer recurrence (κFleiss = 0.35) and when categories 2a, 2b, and 3 were combined (κFleiss = 0.30). Intrareader agreement was considerably lower for NI-RADS categories of the primary site (range Ao = 53.3–70.0%) than for NI-RADS categories of the neck (range Ao = 83.3–90.0%) and DWI of the primary site (range Ao = 93.3–100.0%).ConclusionInterreader agreement of NI-RADS for reporting contrast-enhanced MRI findings is acceptable for the neck but limited for the primary site. Here, DWI has the potential to serve as a reliable additional criterion.Key Points• NI-RADS was originally designed for contrast-enhanced computed tomography with or without positron emission tomography but can also be used for contrast-enhanced magnetic resonance imaging alone.• Overall interreader agreement was acceptable for NI-RADS categories assigned to the neck but should be improved for the primary site, where it was inferior to DWI; similar tendencies were found for intrareader agreement.• DWI is currently no criterion of NI-RADS, but has shown potential to improve its reliability, especially for categories 2a, 2b, and 3 of the primary site.

Predictive value of neck imaging reporting and data system (NIRADS) in CECT/CEMRI of laryngeal and oral cavity squamous cell carcinoma

BackgroundThe neck imaging reporting and data system (NI-RADS) is a structured reporting algorithm linked with further patient management recommendations. This study was conducted to assess the overall and time point predictive value of the NI-RADS in laryngeal and oral cavity squamous cell carcinoma (SCC) using contrast-enhanced magnetic resonance imaging (CEMRI) and contrast-enhanced computed tomography (CECT).ResultsThe rate of tumor recurrence was statistically different among the NI-RADS 1-3 categories with recurrence trend for higher NI-RADS scores. The overall negative predictive value (NPV) of the NI-RADS 1 and 2 were 94.3%, 74.3% respectively, and the positive predictive value (PPV) of the NI-RADS 3 was 80.8%. The overall recurrence rate of NI-RADS 3 was higher in oral cavity SCC (87.5%) compared to the laryngeal SCC (70%). The PPV of overall NI-RADS 3 in the follow-up scans (77.8%) was higher than in the first scan (70.6%). The odd ratio of tumor recurrence in NI-RADS 3 primary lesion was 19.6.ConclusionThe predictive value of NI-RADS was significantly different among its categories. Increasing NI-RADS score is associated with increased recurrence among the treated laryngeal and oral cavity SCC. The morphological and enhancement lexicon features equally assign the NI-RADS 3 score.

Interreader reproducibility of the Neck Imaging Reporting and Data system (NI-RADS) lexicon for the detection of residual/recurrent disease in treated head and neck squamous cell carcinoma (HNSCC)

BackgroundTo evaluate the inter- and intrareader agreement and reproducibility of the NI-RADS scoring system and lexicon with contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CEMRI).MethodsThis retrospective study included 97 CECT and CEMRI scans from 58 treated cases of head and neck squamous cell carcinoma (HNSCC) after the exclusion of head and neck cancers (HNCs) other than SCC and noncontrast and poor quality CT and MRI scans, with a total of 111 primary targets and 124 lymph node (LN) targets. Two experienced readers independently scored the likelihood of residual/recurrence for these targets based on the NI-RADS criteria and filled in report templates for NI-RADS lexicon diagnostic features. Inter- and intraobserver reproducibility was assessed with Cohen’s kappa, and the percent agreement was calculated.ResultsAlmost perfect interreader agreement was found for the final NI-RADS category of the primary lesions and LNs, with K = 0.808 and 0.806, respectively. Better agreement was found for CT than for MRI (K = 0.843 and 0.77, respectively, P value 0.001). There was almost perfect agreement for excluding tissue enhancement (K = 0.826, 95% CI = 0.658–0.993, P value 0.001), with a percent agreement of 96.4%, and substantial agreement for discrete nodular and diffuse mucosal enhancement (K = 0.826, 95% CI = 0.658–0.993, P value 0.001), with a percent agreement of 96.4%. There was fair agreement for focal mucosal nonmass and deep ill-defined enhancement. The intrareader agreement was almost perfect for most of the rated features (K ranging from 0.802 to 1), with the exception of enlarging discrete nodule/mass and focal mucosal nonmass-like enhancement, which had substantial intraobserver agreement (K ranging from 0.768 to 0.786).ConclusionThe individual features of NI-RADS show variable degrees of confidence; however, the overall NI-RADS category was not significantly affected.

Neck Imaging Reporting and Data System: Principles and Implementation.

Head and neck cancer surveillance imaging is diagnostically challenging, often with highly distorted anatomy after surgery and chemoradiation therapy. In the era of standardized reporting, the Neck Imaging Reporting and Data System (NI-RADS) was developed as a numerical classification system to provide clear and concise radiology reports and recommend next management step. There are 5 categories, each conveying a certain level of suspicion for the presence of persistent or recurrent disease. This article reviews the goals of NI-RADS, NI-RADS categories and lexicon, current research, and the future direction of NI-RADS in posttreatment head and neck cancer surveillance.

Neck Imaging Reporting and Data System: What Does Radiologist Want to Know?

The aim of this work was to review Neck Imaging Reporting and Data System (NI-RADS) that was designed for reporting and surveillance of head and neck cancer after therapy and their subsequent management. The categories of NI-RADS can be designated as belonging in 1 of the 4 categories: negative; low suspicion; high suspicion; and definite recurrence. Lexicon of NI-RADS-1 shows nonmass-like distortion of soft tissues, NI-RADS-2 lesions divided into mucosal (2A) versus deep (2B) abnormalities, NI-RADS-3 primary site can either be a submucosal or deep lesion, and NI-RADS-4 is a biopsy-proven residual or recurrent disease. The NI-RADS Lexicon of radiology reporting categories linked to management protocols and surveillance for these patients. Neck Imaging Reporting and Data System is to provide guidance for next-imaging decisions either a follow-up period, biopsy, or surgery.