# Role of Neck Imaging Reporting and Data System in Evaluation of Recurrent/Residual Lesions of Head and Neck Cancers by Contrast-Enhanced Computed Tomography (CECT) With Pathological Correlation

## TL;DR

This study evaluates how the Neck Imaging Reporting and Data System (NI-RADS) helps predict cancer recurrence in head and neck cancer patients using CT scans and pathology results.

## Contribution

The study validates the effectiveness of NI-RADS in predicting recurrence rates in head and neck cancers with clinical and pathological correlation.

## Key findings

- NI-RADS 1 had a 0% recurrence rate and 100% negative predictive value.
- NI-RADS 3 showed high predictive value for recurrence with 61.9% positive predictive value at the primary site.
- NI-RADS 2 was identified as a 'gray zone' requiring further diagnostic evaluation.

## Abstract

Introduction

Head and neck cancers remain a major global health concern, mainly involving the oral cavity, pharynx, larynx, thyroid, and salivary glands. The Neck Imaging Reporting and Data System (NI-RADS) has been developed as a structured framework in order to enhance the quality and consistency of imaging reports for patients undergoing surveillance after treatment for head and neck cancers. NI-RADS provides a standardized lexicon that simplifies the communication of imaging findings. This is crucial given the intricate anatomical and pathological changes that can occur following treatment, which often complicate the interpretation of imaging studies. In the context of head and neck cancer, the post-treatment landscape is characterized by a range of changes, including surgical alterations, radiation effects, and potential disease recurrence. Traditional reporting methods can lead to ambiguities, misinterpretations, and inconsistent management decisions. NI-RADS mitigates these challenges by categorizing findings into a systematic reporting structure that emphasizes clarity. Each category (NI-RADS 1 through NI-RADS 4) offers specific definitions and criteria that assist radiologists in assessing the likelihood of residual disease or recurrence, thus facilitating more informed clinical decision-making and improving patient outcomes. By providing a common language, NI-RADS helps bridge the gap between imaging interpretation and clinical management, ultimately enhancing the overall quality of care for patients with head and neck cancers.

Methods

Contrast-enhanced computed tomography head and neck images of 64 post-treatment cancer patients were evaluated and allotted a NI-RADS category for the primary site and lymph node involvement using the NI-RADS lexicon, and consequently followed up with clinical correlation and histopathological report to determine the sensitivity, specificity, negative predictive value, and positive predictive value.

Results

The majority of cases were classified as NI-RADS 1 (36 cases), followed by NI-RADS 3 (21 cases), and the least were NI-RADS 2 (7 cases). The overall recurrence rate at the primary site was 21.88% (14/64 cases). A strong correlation was observed between NI-RADS categorization and recurrence rates. NI-RADS 1 demonstrated a 0% recurrence rate, confirming its high negative predictive value (100%). It was also observed that NI-RADS 3 is highly effective in detecting recurrences, with a positive predictive value of 61.9% for the primary site and 100% for nodal recurrence. The findings also suggested that NI-RADS 2 remains a gray zone, where careful evaluation and further diagnostic steps are necessary. The lower positive predictive value (33.33%) of NI-RADS 2 for nodal recurrence and the recurrence rate at the primary site (14.3%) indicate that some cases categorized as NI-RADS 2 may progress to recurrence, necessitating individualized follow-up strategies.

Conclusion

This study reinforces the utility of NI-RADS as a reliable tool for risk stratification in head and neck cancer surveillance. The high statistical significance in both primary site and nodal recurrence underscores its predictive accuracy. NI-RADS 1 effectively rules out recurrence and requires routine follow-up. NI-RADS 2 has moderate recurrence rates and requires further evaluation. NI-RADS 3 has a high predictive value for recurrence and necessitates immediate attention.