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.

Posttreatment Imaging in Patients with Head and Neck Cancer without Clinical Evidence of Recurrence: Should Surveillance Imaging Extend Beyond 6 Months?

BACKGROUND AND PURPOSE: Early detection of residual or recurrent disease is important for effective salvage treatment in patients with head and neck cancer. Current National Comprehensive Cancer Network guidelines do not recommend standard surveillance imaging beyond 6 months unless there are worrisome signs or symptoms on clinical examination and offer vague guidelines for imaging of high-risk patients beyond that timeframe. Our goal was to evaluate the frequency of clinically occult recurrence in patients with head and neck squamous cell carcinoma with positive imaging findings (Neck Imaging Reporting and Data Systems scores of 2-4), especially after 6 months. MATERIALS AND METHODS: This institutional review board-approved, retrospective data base search queried neck CT reports with Neck Imaging Reporting and Data Systems scores of 2-4 from June 2014 to March 2018. The electronic medical records were reviewed to determine outcomes of clinical and radiologic follow-up, including symptoms, physical examination findings, pathologic correlation, and clinical notes within 3 months of imaging. RESULTS: A total of 255 cases, all with Neck Imaging Reporting and Data Systems scores of 2 or 3, met the inclusion criteria. Fifty-nine patients (23%) demonstrated recurrence (45 biopsy-proven, 14 based on clinical and imaging progression), and 21 patients (36%) had clinically occult recurrence (ie, no clinical evidence of disease at the time of the imaging examination). The median overall time to radiologically detected, clinically occult recurrence was 11.4 months from treatment completion. CONCLUSIONS: Imaging surveillance beyond the first posttreatment baseline study was critical for detecting clinically occult recurrent disease in patients with head and neck squamous cell carcinoma. More than one-third of all recurrences were seen in patients without clinical evidence of disease; and 81% of clinically occult recurrences occurred beyond 6 months.

Initial Performance of NI-RADS to Predict Residual or Recurrent Head and Neck Squamous Cell Carcinoma.

BACKGROUND AND PURPOSE: The Head and Neck Imaging Reporting and Data System (NI-RADS) surveillance template for head and neck cancer includes a numeric assessment of suspicion for recurrence (1-4) for the primary site and neck. Category 1 indicates no evidence of recurrence; category 2, low suspicion of recurrence; category 3, high suspicion of recurrence; and category 4, known recurrence. Our purpose was to evaluate the performance of the NI-RADS scoring system to predict local and regional disease recurrence or persistence. MATERIALS AND METHODS: This study was classified as a quality-improvement project by the institutional review board. A retrospective database search yielded 500 consecutive cases interpreted using the NI-RADS template. Cases without a numeric score, non-squamous cell carcinoma primary tumors, and primary squamous cell carcinoma outside the head and neck were excluded. The electronic medical record was reviewed to determine the subsequent management, pathology results, and outcome of clinical and radiologic follow-up. RESULTS: A total of 318 scans and 618 targets (314 primary targets and 304 nodal targets) met the inclusion criteria. Among the 618 targets, 85.4% were scored NI-RADS 1; 9.4% were scored NI-RADS 2; and 5.2% were scored NI-RADS 3. The rates of positive disease were 3.79%, 17.2%, and 59.4% for each NI-RADS category, respectively. Univariate association analysis demonstrated a strong association between the NI-RADS score and ultimate disease recurrence, with P < .001 for primary and regional sites. CONCLUSIONS: The baseline performance of NI-RADS was good, demonstrating significant discrimination among the categories 1-3 for predicting disease.

CT Accuracy of Extrinsic Tongue Muscle Invasion in Oral Cavity Cancer.

BACKGROUND AND PURPOSE: Extrinsic tongue muscle invasion in oral cavity cancer upstages the primary tumor to a T4a. Despite this American Joint Committee on Cancer staging criterion, no studies have investigated the accuracy or prognostic importance of radiologic extrinsic tongue muscle invasion, the feasibility of standardizing extrinsic tongue muscle invasion reporting, or the degree of agreement across different disciplines: radiology, surgery, and pathology. The purpose of this study was to assess the agreement among radiology, surgery, and pathology for extrinsic tongue muscle invasion and to determine the imaging features most predictive of extrinsic tongue muscle invasion with surgical/pathologic confirmation. MATERIALS AND METHODS: Thirty-three patients with untreated primary oral cavity cancer were included. Two head and neck radiologists, 3 otolaryngologists, and 1 pathologist prospectively evaluated extrinsic tongue muscle invasion. RESULTS: Fourteen of 33 patients had radiologic extrinsic tongue muscle invasion; however, only 8 extrinsic tongue muscle invasions were confirmed intraoperatively. Pathologists were unable to determine extrinsic tongue muscle invasion in post-formalin-fixed samples. Radiologic extrinsic tongue muscle invasion had 100% sensitivity, 76% specificity, 57% positive predictive value, and 100% negative predictive value with concurrent surgical-pathologic evaluation of extrinsic tongue muscle invasion as the criterion standard. On further evaluation, the imaging characteristic most consistent with surgical-pathologic evaluation positive for extrinsic tongue muscle invasion was masslike enhancement. CONCLUSIONS: Evaluation of extrinsic tongue muscle invasion is a subjective finding for all 3 disciplines. For radiology, masslike enhancement of extrinsic tongue muscle invasion most consistently corresponded to concurrent surgery/pathology evaluation positive for extrinsic tongue muscle invasion. Intraoperative surgical and pathologic evaluation should be encouraged to verify radiologic extrinsic tongue muscle invasion to minimize unnecessary upstaging. Because this process is not routine, imaging can add value by identifying those cases most suspicious for extrinsic tongue muscle invasion, thereby prompting this more detailed evaluation by surgeons and pathologists.

Accuracy of Preoperative Imaging in Detecting Nodal Extracapsular Spread in Oral Cavity Squamous Cell Carcinoma.

BACKGROUND AND PURPOSE: The increasing impact of diagnosing extracapsular spread by using imaging, especially in patients with oropharyngeal squamous cell carcinoma, highlights the need to rigorously evaluate the diagnostic accuracy of imaging. Previous analysis suggested 62.5%-80.9% sensitivity and 60%-72.7% specificity. Our goals were to evaluate the accuracy of imaging in diagnosing extracapsular spread in a cohort of patients with oral cavity squamous cell carcinoma (pathologic confirmation of extracapsular spread routinely available), as a proxy for oropharyngeal squamous cell carcinoma, and to independently assess the reliability of imaging features (radiographic lymph node necrosis, irregular borders/stranding, gross invasion, and/or node size) in predicting pathologically proven extracapsular spread. MATERIALS AND METHODS: One hundred eleven consecutive patients with untreated oral cavity squamous cell carcinoma and available preoperative imaging and subsequent lymph node dissection were studied. Two neuroradiologists blinded to pathologically proven extracapsular spread status and previous radiology reports independently reviewed all images to evaluate the largest suspicious lymph node along the expected drainage pathway. Radiologic results were correlated with pathologic results from the neck dissections. RESULTS: Of 111 patients, 29 had radiographically determined extracapsular spread. Pathologic examination revealed that 28 of 111 (25%) had pathologically proven extracapsular spread. Imaging sensitivity and specificity for extracapsular spread were 68% and 88%, respectively. Radiographs were positive for lymph node necrosis in 84% of the patients in the pathology-proven extracapsular spread group and negative in only 7% of those in the pathologically proven extracapsular spread-negative group. On logistic regression analysis, necrosis (P = .001), irregular borders (P = .055), and gross invasion (P = .068) were independently correlated with pathologically proven extracapsular spread. CONCLUSIONS: Although the specificity of cross-sectional imaging for extracapsular spread was high, the sensitivity was low. Combined logistic regression analysis found that the presence of necrosis was the best radiologic predictor of pathologically proven extracapsular spread, and irregular borders and gross invasion were nearly independently significant.