ACR Neck Imaging Reporting and Data Systems (NI-RADS): A White Paper of the ACR NI-RADS Committee

Radiologic findings of occult nodal metastasis during clinically-N0 salvage total laryngectomy

INTRODUCTION

Occult nodal disease (OND) during clinically-N0 salvage total laryngectomy (TL) can be detected with the Neck-Imaging-Reporting-and-Data-Systems (NI-RADS). However, some patients will still have OND revealed on final pathology.

METHODS

A retrospective study on all patients who had OND during salvage TL with elective neck dissection (END) between 2009 and 2021 was performed. Repeat CT and PET scan interpretation was performed to evaluate their preoperative imaging for suspicious features.

RESULTS

Among 81 salvage TL patients undergoing END, 12 (16%) had OND and a total of 26 occult nodes were identified. On pathology, the average node length [SD] was 0.6 cm [0.3]. On CT, 31% (8 of 26) had rounded morphology. On PET, most had SUVmax below blood pool. One patient scored NI-RADS 2; the rest scored 1.

CONCLUSIONS

On re-review of preoperative imaging, occult nodes were subtle and challenging to identify. Despite no clear impact on survival, performing an END may provide prognostic information.

Radiomic biomarkers of locoregional recurrence: prognostic insights from oral cavity squamous cell carcinoma preoperative CT scans

Introduction

This study aimed to identify CT-based imaging biomarkers for locoregional recurrence (LR) in Oral Cavity Squamous Cell Carcinoma (OSCC) patients.

Methods

Computed tomography scans were collected from 78 patients with OSCC who underwent surgical treatment at a single medical center. We extracted 1,092 radiomic features from gross tumor volume in each patient's pre-treatment CT. Clinical characteristics were also obtained, including race, sex, age, tobacco and alcohol use, tumor staging, and treatment modality. A feature selection algorithm was used to eliminate the most redundant features, followed by a selection of the best subset of the Logistic regression model (LRM). The best LRM model was determined based on the best prediction accuracy in terms of the area under Receiver operating characteristic curve. Finally, significant radiomic features in the final LRM model were identified as imaging biomarkers.

Results and discussion

Two radiomics biomarkers, Large Dependence Emphasis (LDE) of the Gray Level Dependence Matrix (GLDM) and Long Run Emphasis (LRE) of the Gray Level Run Length Matrix (GLRLM) of the 3D Laplacian of Gaussian (LoG σ=3), have demonstrated the capability to preoperatively distinguish patients with and without LR, exhibiting exceptional testing specificity (1.00) and sensitivity (0.82). The group with LRE > 2.99 showed a 3-year recurrence-free survival rate of 0.81, in contrast to 0.49 for the group with LRE ≤ 2.99. Similarly, the group with LDE > 120 showed a rate of 0.82, compared to 0.49 for the group with LDE ≤ 120. These biomarkers broaden our understanding of using radiomics to predict OSCC progression, enabling personalized treatment plans to enhance patient survival.

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.

Biomechanical imaging biomarker during chemoradiotherapy predicts treatment response in head and neck squamous cell carcinoma

Objective. For response-adapted adaptive radiotherapy (R-ART), promising biomarkers are needed to predict post-radiotherapy (post-RT) responses using routine clinical information obtained during RT. In this study, a patient-specific biomechanical model (BM) of the head and neck squamous cell carcinoma (HNSCC) was proposed using the pre-RT maximum standardized uptake value (SUVmax) of18F-fluorodeoxyglucose (FDG) and tumor structural changes during RT as evaluated using computed tomography (CT). In addition, we evaluated the predictive performance of BM-driven imaging biomarkers for the treatment response of patients with HNSCC who underwent concurrent chemoradiotherapy (CCRT).Approach. Patients with histologically confirmed HNSCC treated with definitive CCRT were enrolled in this study. All patients underwent CT two times as follows: before the start of RT (pre-RT) and 3 weeks after the start of RT (mid-RT). Among these patients, 67 patients who underwent positron emission tomography/CT during the pre-RT period were included in the final analysis. The locoregional control (LC), progression-free survival (PFS), and overall survival (OS) prediction performances of whole tumor stress change (TS) between pre- and mid-RT computed using BM were assessed using univariate, multivariate, and Kaplan-Meier survival curve analyses, respectively. Furthermore, performance was compared with the pre and post-RT SUVmax, tumor volume reduction rate (TVRR) during RT, and other clinical prognostic factors.Main results. For both univariate, multivariate, and survival curve analyses, the significant prognostic factors were as follows (p< 0.05): TS and TVRR for LC; TS and pre-RT FDG-SUVmaxfor PFS; and TS only for OS. In addition, for 2 year LC, PFS, and OS prediction, TS showed a comparable predictive performance to post-RT FDG-SUVmax.Significance. BM-driven TS is an effective prognostic factor for tumor treatment response after CCRT. The proposed method can be a feasible functional imaging biomarker that can be acquired during RT using only routine clinical data and may provide useful information for decision-making during R-ART.

Post-treatment surveillance imaging in head and neck cancer: a systematic review

BACKGROUND

In patients treated for head and neck cancer, imaging studies are usually obtained within 3-6 months after treatment for assessment of treatment response. After 6 months, most guidelines advocate clinical follow-up, with imaging reserved for patients with clinically suspect or equivocal findings. However, some guidelines do recommend systematic imaging surveillance, and many clinicians tend to include some type of imaging in their follow-up schemes.

OBJECTIVES

This systematic review focuses on the usefulness of routine (systematic) post-treatment imaging surveillance of head and neck cancer beyond the first 3-6-month baseline imaging study.

METHODS

A systematic literature search was conducted using PubMed and Google Scholar. Additional studies were identified by reviewing reference lists. Only original studies and review papers were considered. Results obtained with systematic post-treatment surveillance imaging were compared to symptom-directed imaging and/or clinical finding-directed imaging.

RESULTS

Five hundred twenty-one records were identified through the database search, and 44 additional records were identified through other sources. Forty-eight articles were selected for the final review. Analysis of these records showed that almost half of cases of locoregional recurrences and/or metastases were only detected by imaging (40.9%), and the mean time of detection of recurrent or metastatic disease (11.5 months) was well beyond the period of the first post-treatment scan. Most authors reported superior results with PET-CT when compared to other imaging techniques.

CONCLUSION

Strong arguments were found in favor of systematic imaging surveillance in locoregional advanced head and neck cancer during at least one and preferably 2 years after treatment.

CRITICAL RELEVANCE STATEMENT

Analysis of the selected records showed that almost half of cases of locoregional recurrences and/or metastases were only detected by imaging. This systematic review suggests that imaging may currently be underused in the post-treatment surveillance of patients with head and neck cancer.

KEY POINTS

• This systematic review focuses on the usefulness of long-term systematic imaging surveillance in patients treated for head and neck cancer. • Analysis of 521 articles revealed that systematic imaging allowed the initial detection of locoregional recurrences and/or metastases in more than 40% of patients. • Imaging may currently be underused in the post-treatment surveillance of patients with advanced head and neck cancer.

The role of gadolinium-based contrast agents in magnetic resonance imaging structured reporting and data systems (RADS)

Among the 28 reporting and data systems (RADS) available in the literature, we identified 15 RADS that can be used in Magnetic Resonance Imaging (MRI). Performing examinations without using gadolinium-based contrast agents (GBCA) has benefits, but GBCA administration is often required to achieve an early and accurate diagnosis. The aim of the present review is to summarize the current role of GBCA in MRI RADS. This overview suggests that GBCA are today required in most of the current RADS and are expected to be used in most MRIs performed in patients with cancer. Dynamic contrast enhancement is required for correct scores calculation in PI-RADS and VI-RADS, although scientific evidence may lead in the future to avoid the GBCA administration in these two RADS. In Bone-RADS, contrast enhancement can be required to classify an aggressive lesion. In RADS scoring on whole body-MRI datasets (MET-RADS-P, MY-RADS and ONCO-RADS), in NS-RADS and in Node-RADS, GBCA administration is optional thanks to the intrinsic high contrast resolution of MRI. Future studies are needed to evaluate the impact of the high T1 relaxivity GBCA on the assignment of RADS scores.

Radiomic Biomarkers of Locoregional Recurrence: Prognostic Insights from Oral Cavity Squamous Cell Carcinoma preoperative CT scans

This study aimed to identify CT-based imaging biomarkers for locoregional recurrence (LR) in Oral Cavity Squamous Cell Carcinoma (OSCC) patients. Our study involved a retrospective review of 78 patients with OSCC who underwent surgical treatment at a single medical center. An approach involving feature selection and statistical model diagnostics was utilized to identify biomarkers. Two radiomics biomarkers, Large Dependence Emphasis (LDE) of the Gray Level Dependence Matrix (GLDM) and Long Run Emphasis (LRE) of the Gray Level Run Length Matrix (GLRLM) of the 3D Laplacian of Gaussian (LoG σ = 3), have demonstrated the capability to preoperatively distinguish patients with and without LR, exhibiting exceptional testing specificity (1.00) and sensitivity (0.82). The group with LRE > 2.99 showed a 3-year recurrence-free survival rate of 0.81, in contrast to 0.49 for the group with LRE ≤ 2.99. Similarly, the group with LDE > 120 showed a rate of 0.82, compared to 0.49 for the group with LDE ≤ 120. These biomarkers broaden our understanding of using radiomics to predict OSCC progression, enabling personalized treatment plans to enhance patient survival.

Diagnostic imaging of salivary gland cancers: REFCOR recommendations by the formal consensus method

OBJECTIVE

To define the indications for each imaging modality in the screening, characterization, extension and follow-up of salivary gland tumors.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group who drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

If a swelling of a salivary gland is palpable for 3 weeks, an ultrasound scan is recommended to confirm a tumoral lesion and rule out differential diagnoses. For a salivary gland tumor, MRI is recommended with diffusion-weighted and dynamic contrast-enhanced techniques. In the case of histologically proven malignancy or a highly suspicious lesion, a CT scan of the neck and chest is recommended to assess the tumor, lymph nodes and metastases. FDG-PET is not currently recommended in routine clinical practice for initial diagnosis, assessment of extension, evaluation of response to treatment, staging of recurrence, or follow-up of salivary gland tumors.

CONCLUSION

Assessing salivary tumors is based on MRI. Extension assessment is based on neck and chest CT.

Diagnostic accuracy of NI-RADS for prediction of head and neck squamous cell carcinoma: a systematic review and meta-analysis

OBJECTIVES

This study aimed to assess the diagnostic performance of NI-RADS for the prediction of recurrence in patients treated for Head and Neck Squamous Cell Carcinoma (HNSCC).

METHODS

A literature search was conducted using various databases to identify relevant articles published from June 2016 onwards. We included studies reporting the diagnostic accuracy of NI-RADS in distinguishing recurrence in patients undergoing imaging surveillance, with pathologic results and/or follow-up as the reference standard. Summary estimates of diagnostic accuracy in terms of sensitivity, specificity, positive likelihood ratio (LR +), negative likelihood ratio (LR -), and diagnostic odds ratio (DOR) were calculated with the hierarchical summary receiver operating characteristic (HSROC) model. Meta-regression and subgroup analyses were conducted to investigate different clinical settings. Study quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

A total of 12 studies were included in the current meta-analysis. The pooled sensitivity and specificity were 0.69 (95% CI 0.59-0.79) and 0.94 (95% CI 0.89-0.97), respectively. For the primary site, the pooled summary estimates were 0.67 (95% CI 0.53-0.78) and 0.95 (95% CI 0.90-0.97), for the nodal sites were 0.64 (95% CI 0.44-0.80) and 0.99 (95% CI 0.98-0.99), respectively. The recurrence rate for NI-RADS categories 1-3 was 0.03 (95% CI 0.02-0.05), 0.13 (95% CI 0.10-0.15), and 0.77 (95% CI 0.73-0.81). Meta-regression revealed that the type of analysis (per person vs. per site) and number of sites (≤ 200 vs. > 200) were significant factors associated with heterogeneity.

CONCLUSIONS

NI-RADS demonstrated high specificity but moderate sensitivity in patients after treatment for HNSCC. Summary estimates showed a significantly higher malignancy rate for NI-RADS category 3 compared to category 2.

Post-treatment monitoring of salivary gland cancer: REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the frequency and modality of post-treatment monitoring of primary salivary gland cancer.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group who drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

Clinical monitoring should be adapted to the risk of recurrence: initially every 3 months and progressively spaced out, becoming annual after 5 years. Post-treatment head and neck and chest imaging is recommended at 3 months. Local and regional monitoring can then be carried out yearly or twice yearly with contrast-enhanced head and neck imaging. An annual chest CT scan is recommended for high-grade tumors. For lesions at high risk of late recurrence, very prolonged annual surveillance (up to 15 years) is recommended, including screening for pulmonary metastases.

CONCLUSION

Given the wide range of malignant salivary gland tumors, the modalities and frequency of post-treatment monitoring must be adapted to the expected course of the disease.

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

BACKGROUND

The Neck Imaging Reporting and Data System (NI-RADS) is a reporting template used in head and neck cancer posttreatment follow-up imaging.

PURPOSE

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.

DATA SOURCES

The MEDLINE, Scopus, and EMBASE databases were searched.

STUDY SELECTION

This systematic review identified 7 studies with a total of 694 patients (1233 lesions) that were eligible for the meta-analysis.

DATA 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.

DATA SYNTHESIS

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.

LIMITATIONS

Given the heterogeneity of the data of the studies, the conclusions should be interpreted with caution.

CONCLUSIONS

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.

Effectiveness of Head-and-Neck Molecular Imaging Reporting and Data System Criterion in Head-and-Neck Squamous Cell Carcinoma PostConcurrent Chemoradiotherapy

Purpose

Postconcurrent chemoradiotherapy (CRT) response assessment has been challenging in locally advanced head-and-neck squamous cell carcinoma (LA-HNSCC) due to prevailing postradiation changes. Molecular response methods have been encouraging, although further clarifications and validations were needed. We tested the effectiveness of a proposed semi-quantitative molecular response criterion in these patients.

Materials and Methods

Two subspecialty-trained physicians evaluated 18F-fluorodeoxyglucose positron emission tomography/computed tomography of LA-HNSCC patients (n = 83) post 3 months CRT using a five points Head and Neck Molecular Imaging-Reporting and Data System (HAN-MI-RADS) criterion. Where available, histopathology examination with clinical and imaging interpretation was taken as a reference for the disease. A diagnostic accuracy comparison was done with the existing Hopkins score. Further effectiveness was analyzed with disease-free survival (DFI) and overall survival (OS).

Results

Metastasis was developed in 11/83 patients at 3 months of evaluation. Of 72 patients, 39, 2, and 31 patients had a complete response, equivocal response, and partial response as per HAN-MI-RADS. Per patient sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for predicting loco-regional disease up to 1 and 2 years was 93.3%, 92.5%, 90.3%, 94.9%, 92.9%, and 84.9%, 91.9%, 90.3%, 87.2%, and 88.6% respectively. One year and two years DFI for each HAN-MI-RADS score showed a statistically significant difference while it was not for OS. The receiver operating characteristic curve analysis showed significantly better outcome predictability of HAN-MI-RADS (area under the curve [AUC] 0.884) than Hopkins (AUC 0.699).

Conclusions

A five points HAN-MI-RADS criterion was found promising for response assessment with less equivocal results and statistically significant higher AUC than Hopkins for loco-regional recurrence prediction.

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

OBJECTIVE

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).

STUDY DESIGN

A retrospective analysis from a prospectively maintained dataset.

SETTING

Tertiary-care comprehensive cancer center in a low-middle-income country.

METHODS

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.

RESULTS

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).

CONCLUSION

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.

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

Objective

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.

Methods

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.

Results

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%.

Conclusion

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.

Imaging of Neck Nodes in Head and Neck Cancers - a Comprehensive Update

Cervical lymph node metastases from head and neck squamous cell cancers significantly reduce disease-free survival and worsen overall prognosis and, hence, deserve more aggressive management and follow-up. As per the eighth edition of the American Joint Committee on Cancer staging manual, extranodal extension, especially in human papillomavirus-negative cancers, has been incorporated in staging as it is important in deciding management and significantly impacts the outcome of head and neck squamous cell cancer. Lymph node imaging with various radiological modalities, including ultrasound, computed tomography and magnetic resonance imaging, has been widely used, not only to demonstrate nodal involvement but also for guided histopathological evaluation and therapeutic intervention. Computed tomography and magnetic resonance imaging, together with positron emission tomography, are used widely for the follow-up of treated patients. Finally, there is an emerging role for artificial intelligence in neck node imaging that has shown promising results, increasing the accuracy of detection of nodal involvement, especially normal-appearing nodes. The aim of this review is to provide a comprehensive overview of the diagnosis and management of involved neck nodes with a focus on sentinel node anatomy, pathogenesis, imaging correlates (including radiogenomics and artificial intelligence) and the role of image-guided interventions.

PET-CT detection of local residual laryngeal carcinoma after definitive (chemo)radiotherapy

BACKGROUND

Positron emission tomography and computed tomography (PET-CT) is currently recommended in evaluating the treatment response after (chemo)radiotherapy ([C]RT). In the larynx, post-treatment changes and physiological uptake make image interpretation more challenging compared to other head and neck sites. Previous research has not addressed imaging factors specifically in the larynx that would help in distinguishing the residual disease and explain the unique challenges of that anatomic area. The study cohorts are small and heterogenous. Our objective was to investigate the ability of PET-CT in diagnosing local residual laryngeal carcinoma, and to uncover imaging factors that could be used in differentiating the residual disease from post-treatment and physiological changes. In the same study cohort, we also aimed to uncover prognostic factors for local residual or recurrent disease.

METHODS

Our retrospective study cohort included 73 patients with T2-T4 laryngeal carcinoma undergoing (C)RT with curative intention, and post-treatment non-contrast-enhanced PET-CT at 2-6 months. Findings were compared between local residual and non-residual disease. Local residual disease was defined as a persistent tumor growth with no evidence of remission in between, confirmed by biopsy, and evident within 6 months from the end of RT. PET-CT was evaluated using a 3-step scale: negative, equivocal, and positive.

RESULTS

Nine (12%) had a local residual tumor and 11 (15%) developed local recurrence, based on the biopsy. The median follow-up of surviving patients was 64 months (range, 28-174). In univariate analysis, primary tumor diameter greater than 2.4 cm (median value), and vocal cord fixation were prognostic for local residual or recurrent disease. Sensitivity, specificity, PPV, and NPV were 100%, 75%, 36%, and 100%, respectively, when the equivocal interpretation was grouped with the positive interpretation. All local residuals, and 28% (18/64) non-residuals, had a primary tumor area SUV_max of over 4.0 (p < 0.001). CT showed a persistent mass at the primary tumor area in 56% of residuals, and in 23% of non-residuals (p > 0.05). By combining SUV_max>4.0 and mass, specificity improved to 91%.

CONCLUSIONS

NPV of post-treatment PET-CT in laryngeal carcinoma is high, but equivocal and positive results have low PPV and require further diagnostics. All local residuals had SUV_max over 4.0. The combination of SUV_max over 4.0 and mass on CT increased specificity, but the sensitivity was low.

Surveillance of head neck cancer: Case for personalized and standardized surveillance

Although surgery, radiotherapy, chemotherapy, or combined treatment often elicits an initial satisfactory response, relapses are frequently observed within two years. Current surveillance methods, including clinical exams and imaging evaluations, have not unambiguously demonstrated a survival benefit, most probably due to a lack of sensitivity in detecting very early recurrence. Current guidelines advise post-treatment surveillance of head and neck cancer (HNC) patients should involve scheduled appointments with a variety of practitioners. The benefits of prolonged routine follow-up on survival have not been proven. Increasing numbers of HNC survivors raise the burden to provide efficient and effective care.

Contemporary Imaging and Reporting Strategies for Head and Neck Cancer: MRI, FDG PET/MRI, NI-RADS, and Carcinoma of Unknown Primary-AJR Expert Panel Narrative Review

CT, MRI, and FDG PET/CT play major roles in the diagnosis, staging, treatment planning, and surveillance of head and neck cancers. Nonetheless, an evolving understanding of head and neck cancer pathogenesis, advances in imaging techniques, changing treatment regimens, and a lack of standardized guidelines have led to areas of uncertainty in the imaging of head and neck cancer. This narrative review aims to address four issues in the contemporary imaging of head and neck cancer. The first issue relates to the standard and advanced sequences that should be included in MRI protocols for head and neck cancer imaging. The second issue relates to approaches to surveillance imaging after treatment of head and neck cancer, including the choice of imaging modality, the frequency of surveillance imaging, and the role of standardized reporting through the Neck Imaging Reporting and Data System. The third issue relates to the role of imaging in the setting of neck carcinoma of unknown primary. The fourth issue relates to the role of simultaneous PET/MRI in head and neck cancer evaluation. The authors of this review provide consensus opinions for each issue.

Personalizing Surveillance in Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) encompasses a spectrum of heterogeneous diseases originating in the oral cavity, pharynx, and larynx. Within the United States, head and neck cancer (HNC) accounts for 66,470 new cases, or 3% of all malignancies, annually.¹ The incidence of HNC is rising, largely driven by increases in oropharyngeal cancer.^2-4 Recent molecular and clinical advancements, particularly with regard to molecular and tumor biology, reflect the heterogeneity of the subsites contained within the head and neck. Despite this, existing guidelines for post-treatment surveillance remain broad without much consideration given to different anatomic subsites and etiologic factors (such as human papillomavirus [HPV] status or tobacco exposure).⁵ Surveillance incorporating the physical examination, imaging, and emerging molecular biomarkers is an essential part of care for patients treated for HNC and allows for the detection of locoregional recurrence, distant metastases, and second primary malignancies aiming for better functional and survival outcomes. Additionally, it allows for evaluation and management of post-treatment complications.

18F-FDG PET/CT Staging of Head and Neck Cancer: Interobserver Agreement and Accuracy-Results from Multicenter ACRIN 6685 Clinical Trial

To our knowledge, no prior multicenter clinical trial has reported interobserver agreement of 18F-FDG PET/CT scans for staging of clinical N0 neck in head and neck cancer. Methods: A total of 287 participants were recruited. For visual analysis, positive nodal uptake of 18F-FDG was defined as uptake visually greater than activity seen in the blood pool. Results: The negative predictive value of the 18F-FDG PET/CT for N0 clinical neck was 86% or above for visual assessment (95% CI, 86%-88%) for the 2 central readers and above 90% (95% CI, 90%-95%) for SUVmax for central reads and site reads dichotomized at the optimal cutoff value of 1.8 and the prespecified cutoff value of 3.5, respectively. The κ coefficients between the 2 expert readers and between central reads and site reads varied between 0.53 and 0.78. Conclusion: The NPV of the 18F-FDG PET/CT for N0 clinical neck was 86% or above for visual assessment and above 90% for SUVmax cut points of 1.8 and 3.5 with moderate to substantial agreements.

Discordance Between Oncology Clinician-Perceived and Radiologist-Intended Meaning of the Postradiotherapy Positron Emission Tomography/Computed Tomography Freeform Report for Head and Neck Cancer

Importance

Assessment of response after radiotherapy (RT) using 18F-fluorodeoxyglucose positron emission tomography (PET) with computed tomography (CT) is routine in managing head and neck squamous cell carcinoma (HNSCC). Freeform reporting may contribute to a clinician's misunderstanding of the nuclear medicine (NM) physician's image interpretation, with important clinical implications.

Objective

To assess clinician-perceived freeform report meaning and discordance with NM interpretation using the modified Deauville score (MDS).

Design, Setting, and Participants

In this retrospective cohort study that was conducted at an academic referral center and National Cancer Institute-designated Comprehensive Cancer Center and included patients with HNSCC treated with RT between January 2014 and December 2019 with a posttreatment PET/CT and 1 year or longer of follow-up, 4 masked clinicians independently reviewed freeform PET/CT reports and assigned perceived MDS responses. Interrater reliability was determined. Clinician consensus-perceived MDS was then compared with the criterion standard NM MDS response derived from image review. Data analysis was conducted between December 2021 and February 2022.

Exposures

Patients were treated with RT in either the definitive or adjuvant setting, with or without concurrent chemotherapy. They then underwent posttreatment PET/CT response assessment.

Main Outcomes and Measures

Clinician-perceived (based on the freeform PET/CT report) and NM-defined response categories were assigned according to MDS. Clinical outcomes included locoregional control, progression-free survival, and overall survival.

Results

A total of 171 patients were included (45 women [26.3%]; median [IQR] age, 61 [54-65] years), with 149 (87%) with stage III to IV disease. Of these patients, 52 (30%) received postoperative RT and 153 (89%) received concurrent chemotherapy. Interrater reliability was moderate (κ = 0.68) among oncology clinicians and minimal (κ = 0.36) between clinician consensus and NM. Exact agreement between clinician consensus and the NM was 64%. The NM-rated MDS was significantly associated with locoregional control, progression-free survival, and overall survival.

Conclusions and Relevance

The results of this cohort study suggest that considerable variation in perceived meaning exists among oncology clinicians reading freeform HNSCC post-RT PET/CT reports, with only minimal agreement between MDS derived from clinician perception and NM image interpretation. The NM use of a standardized reporting system, such as MDS, may improve clinician-NM communication and increase the value of HNSCC post-RT PET/CT reports.

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.

Lessons learnt from the global iodinated contrast media shortage in head and neck imaging

A recent shortage in the global supply of iodinated contrast media (ICM) has required health service providers to review their contrast administration policies and implement strategies to conserve inventory. This article will review the current best practices in head and neck imaging for a variety of common presentations and provide examples where alternative imaging can be considered due to the recent ICM shortage. Ultrasound and MRI techniques can feature heavily in many diagnostic processes in head and neck pathology, and a variety of common presentations can be appropriately investigated through clinical evaluation or naso-endoscopy. In many instances, for the routine assessment of non-acute adult and paediatric head and neck presentations, the use of contrast-enhanced CT can be safely minimised to conserve ICM if required.

Normalized Parameters of Dynamic Contrast-Enhanced Perfusion MRI and DWI-ADC for Differentiation between Posttreatment Changes and Recurrence in Head and Neck Cancer

BACKGROUND AND PURPOSE

Differentiating recurrence from benign posttreatment changes has clinical importance in the imaging follow-up of head and neck cancer. This study aimed to investigate the utility of normalized dynamic contrast-enhanced MR imaging and ADC for their differentiation.

MATERIALS AND METHODS

This study included 51 patients with a history of head and neck cancer who underwent follow-up dynamic contrast-enhanced MR imaging with DWI-ADC, of whom 25 had recurrences and 26 had benign posttreatment changes. Quantitative and semiquantitative dynamic contrast-enhanced MR imaging parameters and ADC of the ROI and reference region were analyzed. Normalized dynamic contrast-enhanced MR imaging parameters and normalized DWI-ADC parameters were calculated by dividing the ROI by the reference region.

RESULTS

Normalized plasma volume, volume transfer constant between extravascular extracellular space and blood plasma per minute (K ^trans), area under the curve, and wash-in were significantly higher in patients with recurrence than in those with benign posttreatment change (P = .003 to <.001). The normalized mean ADC was significantly lower in patients with recurrence than in those with benign posttreatment change (P < .001). The area under the receiver operating characteristic curve of the combination of normalized dynamic contrast-enhanced MR imaging parameters with significance (normalized plasma volume, normalized extravascular extracellular space volume per unit tissue volume, normalized K ^trans, normalized area under the curve, and normalized wash-in) and normalized mean ADC was 0.97 (95% CI, 0.93-1).

CONCLUSIONS

Normalized dynamic contrast-enhanced MR imaging parameters, normalized mean ADC, and their combination were effective in differentiating recurrence and benign posttreatment changes in head and neck cancer.

Post-Treatment Neck Dissection of Tonsillar and Base of Tongue Squamous Cell Carcinoma in the Era of PET-CT, HPV, and p16

Human-papillomavirus (HPV)-positive tonsillar and base of tongue carcinomas (TSCC/BOTSCC) are rising in incidence and treatments with radiotherapy, chemoradiotherapy (RT/CRT), and neck dissections (NDs) have several side effects. Therefore, an improved selection of patients needing salvage NDs would be beneficial. We examined the prevalence and localisations of viable tumour cells in neck lymph nodes in patients post-RT/CRT, identified by fluorodeoxyglucose positron-emission tomography with computer-tomography (FDG PET-CT), with a focus on HPV-associated tumours. Patients with 217 TSCC/BOTSCC with tumours assessed for HPV-DNA and p16^INK4a undergoing FDG PET-CT 12 weeks after treatment and/or an ND were included. The FDG PET-CT data were compared with the findings in the pathology report after the ND. In total, 36/217 (17%) patients were selected for an ND due to positive findings in post-treatment FDG PET-CT. Of these, 35/36 were HPV-associated, 10/36 (28%) had viable tumour cells in the pathology reports of the neck specimen, and 8/10 (80%) were consistent with the FDG PET-CT findings, while 2/36 (5%) were missed by FDG PET-CT. We conclude that FDG PET-CT 12 weeks after RT/CRT is useful, but not completely reliable for finding all the metastases of HPV-associated TSCC/BOTSCC. Nonetheless, our data indicate that an ND could be more selectively guided by FDG PET-CT.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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

BACKGROUND AND PURPOSE

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.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSIONS

Adding MR imaging diagnostic characteristics like T2WI, DWI, and ADC to the American College of Radiology NI-RADS improved diagnostic accuracy and sensitivity.

PET-CT in Clinical Adult Oncology-V. Head and Neck and Neuro Oncology

Simple Summary

Positron emission tomography (PET), typically combined with computed tomography (CT) has become a critical advanced imaging technique in oncology. With PET-CT, a radioactive molecule (radiotracer) is injected in the bloodstream and localizes to sites of tumor because of specific cellular features of the tumor that accumulate the targeting radiotracer. The CT scan, performed at the same time, provides information to facilitate attenuation correction, so that radioactivity from deep or dense structures can be better visualized, but with head and neck malignancies it is critical to provide correlating detailed anatomic imaging. PET-CT has a variety of applications in oncology, including staging, therapeutic response assessment, restaging, and surveillance. This series of six review articles provides an overview of the value, applications, and imaging and interpretive strategies of PET-CT in the more common adult malignancies. The fifth report in this series provides a review of PET-CT imaging in head and neck and neuro oncology.

Abstract

PET-CT is an advanced imaging modality with many oncologic applications, including staging, assessment of response to therapy, restaging, and longitudinal surveillance for recurrence. The goal of this series of six review articles is to provide practical information to providers and imaging professionals regarding the best use of PET-CT for specific oncologic indications, and the potential pitfalls and nuances that characterize these applications. In addition, key tumor-specific clinical information and representative PET-CT images are provided to outline the role that PET-CT plays in the management of oncology patients. Hundreds of different types of tumors exist, both pediatric and adult. A discussion of the role of FDG PET for all of these is beyond the scope of this review. Rather, this series of articles focuses on the most common adult malignancies that may be encountered in clinical practice. It also focuses on FDA-approved and clinically available radiopharmaceuticals, rather than research tracers or those requiring a local cyclotron. The fifth review article in this series focuses on PET-CT imaging in head and neck tumors, as well as brain tumors. Common normal variants, key anatomic features, and benign mimics of these tumors are reviewed. The goal of this review article is to provide the imaging professional with guidance in the interpretation of PET-CT for the more common head and neck malignancies and neuro oncology, and to inform the referring providers so that they can have realistic expectations of the value and limitations of PET-CT for the specific type of tumor being addressed.

PET/MR Imaging in Evaluating Treatment Failure of Head and Neck Malignancies: A Neck Imaging Reporting and Data System-Based Study

BACKGROUND AND PURPOSE

PET/MR imaging is a relatively new hybrid technology that holds great promise for the evaluation of head and neck cancer. The aim of this study was to assess the performance of simultaneous PET/MR imaging versus MR imaging in the evaluation of posttreatment head and neck malignancies, as determined by its ability to predict locoregional recurrence or progression after imaging.

MATERIALS AND METHODS

The electronic medical records of patients who had posttreatment PET/MR imaging studies were reviewed, and after applying the exclusion criteria, we retrospectively included 46 studies. PET/MR imaging studies were independently reviewed by 2 neuroradiologists, who recorded scores based on the Neck Imaging Reporting and Data System (using CT/PET-CT criteria) for the diagnostic MR imaging sequences alone and the combined PET/MR imaging. Treatment failure was determined with either biopsy pathology or initiation of new treatment. Statistical analyses including univariate association, interobserver agreement, and receiver operating characteristic analysis were performed.

RESULTS

There was substantial interreader agreement among PET/MR imaging scores (κ = 0.634; 95% CI, 0.605-0.663). PET/MR imaging scores showed a strong association with treatment failure by univariate association analysis, with P < .001 for the primary site, neck lymph nodes, and combined sites. Receiver operating characteristic curves of PET/MR imaging scores versus treatment failure indicated statistically significant diagnostic accuracy (area under curve range, 0.864-0.987; P < .001).

CONCLUSIONS

Simultaneous PET/MR imaging has excellent discriminatory performance for treatment outcomes of head and neck malignancy when the Neck Imaging Reporting and Data System is applied. PET/MR imaging could play an important role in surveillance imaging for head and neck cancer.

ADC for Differentiation between Posttreatment Changes and Recurrence in Head and Neck Cancer: A Systematic Review and Meta-analysis

BACKGROUND

Previous studies reported that the ADC values of recurrent head and neck cancer lesions are lower than those of posttreatment changes, however, the utility of ADC to differentiate them has not been definitively summarized and established.

PURPOSE

Our aim was to evaluate the diagnostic benefit of ADC calculated from diffusion-weighted imaging in differentiating recurrent lesions from posttreatment changes in head and neck cancer.

DATA SOURCES

MEDLINE, Scopus, and EMBASE data bases were searched for studies.

STUDY SELECTION

The review identified 6 prospective studies with a total of 365 patients (402 lesions) who were eligible for the meta-analysis.

DATA ANALYSIS

Forest plots were used to assess the mean difference in ADC values. Heterogeneity among the studies was evaluated using the Cochrane Q test and the I² statistic.

DATA SYNTHESIS

Among included studies, the overall mean of ADC values of recurrent lesions was 1.03 × 10^-3mm²/s and that of the posttreatment changes was 1.51 × 10^-3mm²/s. The ADC value of recurrence was significantly less than that of posttreatment changes in head and neck cancer (pooled mean difference: -0.45; 95% CI, -0.59-0.32, P < .0001) with heterogeneity among studies. The threshold of ADC values between recurrent lesions and posttreatment changes was suggested to be 1.10 × 10^-3mm²/s.

LIMITATIONS

Given the heterogeneity of the data of the study, the conclusions should be interpreted with caution.

CONCLUSIONS

The ADC values in recurrent head and neck cancers are lower than those of posttreatment changes, and the threshold of ADC values between them was suggested.

To scan or not to scan: the dilemma of post-treatment imaging surveillance of head and neck cancer

Locoregional recurrence remains common after treatment of head and neck cancer, warranting careful surveillance in follow-up. While randomized data support an initial PET/CT several months after treatment, evidence supporting subsequent imaging is limited, and most recurrences ultimately manifest clinically. Cooperative group studies and consensus guidelines vary widely in their recommendations regarding surveillance imaging. Patients with indeterminate findings, new symptoms, or areas difficult to examine in clinic may avoid invasive and potentially morbid interventions with judicious use of subsequent imaging. For any patient undergoing post-treatment imaging, standardized reporting criteria provide a framework for risk-stratification that can enhance communication and potentially guide management.

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

OBJECTIVES

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.

STUDY DESIGN

Retrospective cohort study.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

LEVEL OF EVIDENCE

4 Laryngoscope, 2022.

Inter-rater concordance and operating definitions of radiologic nodal feature assessment in human papillomavirus-positive oropharyngeal carcinoma

BACKGROUND AND PURPOSE

This study aims to evaluate the reliability of radiologic nodal feature assessment in clinical node-positive human papillomavirus-positive oropharyngeal carcinoma.

MATERIALS AND METHODS

Baseline CTs or MRIs of clinical node-positive human papillomavirus-positive oropharyngeal carcinoma diagnosed between 2012 and 2015 were reviewed independently by two neuroradiologists for seven nodal features: radiologic nodal involvement, cystic change, presence of necrosis, clustering, conglomeration, coalescence, and extranodal extension. Consensus operating definitions were derived after discussion. The features were re-reviewed in a randomly selected cohort. Levels of certainty (probability of presence: <25%, ∼50%, ∼75%, and >90%) were recorded. Interrater concordance was calculated using Cohen's kappa coefficient.

RESULTS

A total of 413 patients (826 necks) were eligible. At initial review, the inter-rater kappa values for: radiologic nodal involvement, cystic change, necrosis, clustering, conglomeration, coalescence, and extranodal extension were 0.92, 0.64, 0.48, 0.32, 0.32, 0.62, and 0.56, respectively. A re-review of 94 randomly selected cases (188 necks) after consolidation of operating definitions for nodal features showed that the inter-rater kappa values of these features were 0.83, 0.62, 0.58, 0.32, 0.18, 0.68, and 0.74 when considering ≥50% certainty as positive, and improved to 0.94, 0.66, 0.59, 0.33, 0.19, 0.76, and 0.86 when considering ≥75% certainty as positive.

CONCLUSION

Clearly defined nomenclature results in improved interrater reliability when assessing radiologic nodal features, especially for coalescent adenopathy and extranodal extension. Higher levels of certainty are associated with higher inter-rater agreement. Radiology reporting should include clear definitions of clinically relevant nodal features as well as levels of certainty to serve various needs in clinical care and research.

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

OBJECTIVES

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.

METHODS

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.

RESULTS

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).

CONCLUSION

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.

18F FDG imaging - response criteria in tumors

With the progress of medical oncology, it became apparent that anatomical imaging is oftentimes insufficient for therapy response evaluation. Hybrid imaging, namely ¹⁸F-FDG PET/CT has helped to overcome these limitations. The aim of this paper is to emphasize the utility and impact in clinical use of ¹⁸F-FDG PET/CT, and to give an overview of the most important ¹⁸F-FDG PET/CT tumor response criteria. We also focus on standardization of hybrid imaging techniques as this is of outmost importance to provide reliable imaging evaluation.

Lymph Node Dissection: Principles and Postoperative Imaging

The management of neck nodes in head and neck cancer is critical, given a markedly increased poor prognosis in patients with nodal metastasis. The surgical management of neck nodes has undergone radical changes secondary to a paradigm shift from curative surgery to nonsurgical organ and function-preserving options, such as radiation therapy. In the neck after treatment, radiologists should be familiar with imaging findings in various types of neck dissections and post-chemoradiation changes, along with signs of residual or recurrent disease. A multidisciplinary approach is essential with well-designed evidence-based surveillance imaging protocols and standardized reporting.

Surgical Free Flaps and Grafts in Head and Neck Reconstruction: Principles and Postoperative Imaging

This review article discusses the basic principles behind the use of flaps and grafts for reconstructive surgery in the head and neck, with a special emphasis on the types of commonly used free flaps, their imaging appearance as well as some frequently encountered postoperative complications. Given the ubiquity and complexity of these reconstructive techniques, it is essential that head and neck radiologists be familiar in distinguishing between the expected evolving findings, complications, and tumor recurrence.

NI-RADS to Predict Residual or Recurrent Head and Neck Squamous Cell Carcinoma

American College of Radiology NI-RADS is a surveillance imaging template used to predict residual or recurrent tumor in the setting of head and neck cancer. The lexicon and imaging template provides a framework to standardize the interpretations and communications with referring physicians and provides linked management recommendations, which add value in patient care. Studies have shown reasonable interreader agreement and excellent discriminatory power among the different NI-RADS categories. This article reviews the literature associated with NI-RADS and serves as a practical guide for radiologists interested in using the NI-RADS surveillance template at their institution, highlighting frequently encountered pearls and pitfalls.

Postoperative Pharynx and Larynx

Cancers of the pharynx and larynx are treated using a combination of chemotherapeutic, radiation, and surgical techniques, depending on the cancer type, biology, location, and stage, as well as patient and other factors. When imaging in the postsurgical setting, the knowledge of the type of tumor, preoperative appearance, and type of surgery performed is essential for accurate interpretation. Surgical anatomic changes, surgical implants/devices, and potential postsurgical complications must be differentiated from suspected recurrent tumors.

PET/CT and PET/MR Imaging of the Post-treatment Head and Neck: Traps and Tips

PET/computed tomography and PET/MR imaging are used to evaluate the post-treatment neck. Although 18F-FDG is helpful in the staging and treatment response assessment of head and neck cancer, recently developed PET radiotracers targeting specific surface markers are promising for applications of diagnostic problem solving and improved extent delineation. Diffusion-weighted MR imaging is helpful in the differential diagnosis of head and neck neoplasms, and improves the sensitivity and specificity for the detection of certain pathologies. Following standardized imaging parameters for PET/computed tomography and diffusion-weighted imaging in PET/MR imaging improves diagnostic accuracy and allows for future research data mining.

Posttreatment Magnetic Resonance Imaging Surveillance of Head and Neck Cancers

Treatment strategies and recommended surveillance imaging differ for head and neck cancers depending on subsite and neoplasm type, and pose confusion for referring physicians and interpreting radiologists. The superior soft tissue resolution offered by magnetic resonance imaging is most useful in the surveillance of cancers with high propensities for intraorbital, intracranial, or perineural disease spread, which most commonly include those arising from the sinonasal cavities, nasopharynx, orbits, salivary glands, and the skin. This article discusses recommended surveillance protocoling and reviews treatment approaches, common posttreatment changes, and pearls for identifying disease recurrence in a subsite-based approach.

Incidence of Second Primary Lung Cancer After Low-Dose Computed Tomography vs Chest Radiography Screening in Survivors of Head and Neck Cancer: A Secondary Analysis of a Randomized Clinical Trial

Importance

In head and neck cancer survivors, lung cancer screening may aid in detecting a second primary lung cancer or metastatic head and neck cancer earlier in the course of disease, which may improve treatment outcomes. However, no randomized data exist to assess the value of lung cancer screening in this population.

Objective

To evaluate the incidence of second primary lung cancer in survivors of head and neck cancer survivors with screening low-dose computed tomography (CT) vs chest radiography (CXR).

Design, Setting and Participants

For this ad hoc secondary analysis of a randomized clinical trial, head and neck cancer survivors were identified from the National Lung Screening Trial, which enrolled participants from August 2002 to April 2004. This randomized clinical trial compared screening using low-dose CT chest vs CXR in patients aged 55 to 74 years with at least a 30 pack-year history of cigarette smoking and who were current smokers or had quit within the past 15 years and who were at high risk for lung cancer. The incidences of second primary lung cancer and second primary head and neck cancer were compared with screening using low-dose CT vs CXR. Data were analyzed from December 1, 2020, to June 30, 2021.

Interventions

Screening low-dose CT of the chest vs CXR.

Main Outcomes and Measures

The primary outcome was the incidence of a second primary lung cancer.

Results

Among 53 452 enrolled participants, we identified 171 survivors of head and neck cancer, of whom 82 were screened with low-dose CT of the chest and 89 with CXR. Participants' mean (SD) age was 61 (5) years, and 132 were men (77.2%). The incidence of lung cancer was higher among head and neck cancer survivors compared with participants without head and neck cancer (2080 per 100 000 person-years [2.1%] vs 609 per 100 000 person-years [0.6%]; adjusted rate ratio, 2.54; 95% CI, 1.63-3.95). In head and neck cancer survivors, the incidence of second primary lung cancer was 2610 cases per 100 000 person-years in the low-dose CT group vs 1594 cases per 100 000 person-years in the CXR group (rate ratio, 1.55; 95% CI, 0.59-3.63). In head and neck cancer survivors, overall survival was 7.07 years with low-dose CT vs 6.66 years with CXR (log-rank P = .48).

Conclusions and Relevance

The results of this ad hoc secondary analysis of a randomized clinical trial suggest that head and neck cancer survivors are at especially high risk for a second primary lung cancer. These findings underscore the importance of low-dose CT screening in head and neck cancer survivors with significant cigarette smoking history who are fit to undergo treatment with curative intent.

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

OBJECTIVES/HYPOTHESIS

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.

STUDY DESIGN

Quality improvement study.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

LEVEL OF EVIDENCE

Level 4 Laryngoscope, 2021.