Computed tomography performance in predicting extranodal extension in HPV‐positive oropharynx cancer

A review of histopathologic assessment for head and neck oncologists

GOAL OF REVIEW

With a deeper understanding of histopathologic assessment, head and neck oncology specialists (surgical oncologists, radiation oncologists, and medical oncologists) will be better equipped to address the increasing complexity encompassing head and neck cancer management.

INTRODUCTION

Histopathologic assessment of surgical specimens imparts crucial information that is essential for post-operative treatment planning and prognostication for patients with head and neck squamous cell carcinoma (HNSCC). Herein, we discuss the most current guidelines and recommendations to elucidate the clinically relevant histopathologic features in HNSCC. This review discusses the following pathology features: extranodal extension, margins, perineural invasion, histologic grade, dysplasia, depth of invasion, lymphovascular invasion, and other considerations such as p16 immunohistochemistry, HPV in situ hybridization and worst pattern of invasion.

DISCUSSION

Understanding histopathology in HNSCC is essential for accurate diagnosis, prognostication, understanding tumor behavior, and treatment management. This complexity of care has led to consensus guidelines from numerous authorities which this paper discusses and summarizes for readers.

CONCLUSION

The understanding of key histopathology elements in HNSCC will augment multidisciplinary discussions and improve patient care. The current variability in existing consensus guidelines highlights the need for improved standardization of histopathology reporting in HNSCC. Standardization will enhance diagnostic accuracy, guide clinical decision-making, and facilitate the development of more effective treatment strategies.

International multispecialty expert physician preoperative identification of extranodal extension in patients with oropharyngeal cancer using computed tomography: Prospective blinded human inter-observer performance evaluation

BACKGROUND

Pathologic extranodal extension (pENE) is a crucial prognostic factor in oropharyngeal cancer (OPC), but determining pENE from imaging has high inter-observer variability. The role of clinician specialty in the accuracy of imaging-detected extranodal extension (iENE) remains unclear. The purpose of this study is to assess the influence of clinician specialty on the accuracy of preoperative iENE detection in human papillomavirus (HPV)-positive OPC using computed tomography (CT) imaging.

METHODS

This prospective observational study evaluated pretherapy CT images from 24 HPV-positive OPC patients (30 scans, including duplicates). Thirty-four expert observers (11 radiologists, 12 surgeons, 11 radiation oncologists) assessed iENE and reported radiologic criteria and confidence. Ground-truth pENE status was confirmed pathologically. Accuracy, sensitivity, specificity, area under the receiver operating characteristic curve, and Brier scores were compared across specialties. Logistic regression determined significant predictors of pENE, whereas Fleiss' kappa measured interobserver agreement.

RESULTS

Median accuracy was 0.57 (95% CI, 0.39-0.73), with no specialty showing performance beyond chance (median area under the receiver operating characteristic curve, 0.64). Minor differences were noted: surgeons had lower Brier scores (0.26 vs. 0.33, p < .01) and higher sensitivity (0.69 vs. 0.48) compared to radiologists and oncologists. Predictive signs included indistinct capsular contour and nodal necrosis. Interobserver agreement was weak (κ < 0.6).

CONCLUSIONS

Diagnostic performance for iENE on CT in HPV-positive OPC remains poor across specialties, with high variability and low accuracy. These findings highlight the need for automated systems or improved imaging methods to enhance iENE assessments.

Predicting Extranodal Extension with Preoperative Contrast-enhanced CT in Patients with Oropharyngeal Squamous Cell Carcinoma

Purpose To develop a practical, easily implementable risk stratification model based on preoperative contrast-enhanced CT (CECT) nodal features to predict the probability of pathologic extranodal extension (pENE) in patients with oropharyngeal squamous cell carcinoma (OPSCC). Materials and Methods Preoperative CECT studies in consecutive patients with OPSCC who underwent surgical resection between October 2012 and October 2020 were examined by four neuroradiologists, blinded to the pathologic outcome, for imaging features of pENE. The pathology report was queried for the presence of pENE. Decision tree analysis with cost-complexity pruning was performed to identify a clinically pragmatic model to predict pENE. Results A total of 162 patients (median age, 60 years [IQR, 54-67 years]; 134 male, 28 female) with 208 dissected heminecks were included. The primary OPSCC site for most patients was tonsil (67%, 109 of 162) or base of tongue (31%, 50 of 162). Most patients had early-stage disease (American Joint Committee on Cancer Staging Manual eighth edition category T0-T2, 93% [151 of 162]; N0-N1, 90% [145 of 162]). Pathologically confirmed pENE was reported in 28% (45 of 162) of patients. CECT features that were significantly associated with pENE on univariable analysis included size, necrosis, spiculation, perinodal stranding, and infiltration of adjacent structures. Decision tree analysis identified a predictive model including spiculation or irregular margins, matted nodes, and infiltration of adjacent structures. The model had a sensitivity of 41% (19 of 46) and specificity of 96% (157 of 162) for predicting pENE. Conclusion The developed model for predicting pENE using preoperative CECT features is practical and had high specificity in patients with OPSCC. Further prospective study is warranted to determine impact on clinical management and outcomes. Keywords: Head/Neck, CT, Radiation Therapy/Oncology, Neoplasms-Primary, Oncology, Decision Analysis, Observer Performance Supplemental material is available for this article. © RSNA, 2025.

Nodal assessment and extranodal extension in head and neck squamous cell cancer: insights from computed tomography and magnetic resonance imaging

PURPOSE

The aim of the study was to evaluate the concordance between computed tomography (CT)/magnetic resonance imaging (MRI) and histological examination in the evaluation of lymph nodal involvement (N+) and extranodal extension (ENE+) in patients with squamous cell cancer of the head-neck district (HNSCC). The second end point was to evaluate which of the imaging features was more sensitive and specific in establishing N+ and ENE+, and comparing the diagnostic accuracy between CT and MRI.

MATERIAL AND METHODS

58 patients with HNSCC undergoing surgical treatment with lymph node dissection at the Policlinico of Bari were enrolled in this retrospective study. The criteria used for identifying radiological N+ (rN+) included six characteristics; the presence of any two or more criteria out of these six was considered rN+. For each rN+, the radiological extranodal extension (rENE+) was evaluated analyzing three characteristics; rENE was considered positive if any one criterion was present.

RESULTS

Of 167 lymph nodes, 45/167 (27%) had rN+, out of which 20/45 (44%) were rENE+. On pathological examination, 38/45 (84%) nodes were N+ and 11/20 (55%) were ENE+. The agreement between imaging and histology in the evaluation of N was (149/167) 89% with a good concordance (k = 0.7). The agreement between imaging and histology in the evaluation of ENE was (35/45) 78% with a moderate concordance (k = 0.5). Loss of fatty hilum was found to be the most sensitive (84%) imaging finding in N+ evaluation. Capsular irregularity with fat stranding had the highest sensitivity (82%) for the determination of ENE+. Comparing CT and MRI imaging in the evaluation of N+ and ENE+, we found no statistically significant differences (p-value of 0.3 for N+ and p-value of 0.3 for ENE +).

CONCLUSIONS

Imaging has good confidence in detecting rN+ but modest in assessing rENE+. Further research could improve the imaging specificity for the determination of rENE.

International Multi-Specialty Expert Physician Preoperative Identification of Extranodal Extension n Oropharyngeal Cancer Patients using Computed Tomography: Prospective Blinded Human Inter-Observer Performance Evaluation

Importance

Extranodal extension (pENE) is a critical prognostic factor in oropharyngeal cancer (OPC) that drives therapeutic disposition. Determination of pENE from radiological imaging has been associated with high inter-observer variability. However, the impact of clinician specialty on human observer performance of imaging-detected extranodal extension (iENE) remains poorly understood.

Objective

To characterize the impact of clinician specialty on the accuracy of pre-operative iENE in human papillomavirus-positive (HPV+) OPC using computed tomography (CT) images.

Design Setting and Participants

This prospective observational human performance study analyzed pre-therapy CT images from 24 HPV+ OPC patients, with duplication of 6 scans (n=30) of which 21 were pathologically confirmed pENE. Thirty-four expert observers, including 11 radiologists, 12 surgeons, and 11 radiation oncologists, independently assessed these scans for iENE and reported human-detected radiologic criteria and observer confidence.

Main Outcomes and Measures

The primary outcomes included accuracy, sensitivity, specificity, area under the receiver operating characteristic curve (AUC), and Brier score for each physician, compared to ground-truth pENE. The significance of radiographic signs for prediction of pENE were determined through logistic regression analysis. Fleiss' kappa measured interobserver agreement, and Hanley-MacNeil AUC discrimination testing.

Results

Median accuracy across all specialties was 0.57 (95%CI 0.39 to 0.73), with no specialty showing discriminate performance greater than random estimation (median AUC 0.64, 95%CI 0.44 to 0.83). Significant differences between radiologists and surgeons in Brier scores (0.33 vs. 0.26, p < 0.01), radiation oncologists and surgeons in sensitivity (0.48 vs. 0.69, p > 0.1), and radiation oncologists and radiologists/surgeons in specificity (0.89 vs. 0.56, p > 0.1). Indistinct capsular contour and nodal necrosis were significant predictors of correct pENE status among all specialties. Interobserver agreement was weak for all the radiographic criteria, regardless of specialty (κ<0.6).

Conclusions and Relevance

Multiobserver testing shows physician discrimination of HPV+OPC pENE on pre-operative CT remains non-different than blind guessing, with high interrater variability and low diagnostic accuracy, regardless of clinician specialty. While minor differences in diagnostic performance among specialties are noted, they do not significantly affect the overall poor agreement and discrimination rates observed. The findings underscore the need for further research into automated detection systems or enhanced imaging techniques to improve the accuracy and reliability of iENE assessments in clinical practice.

Imaging Characteristics Predictive of Cervical Extranodal Tumor Extension in Patients With Head and Neck Squamous Cell Carcinoma

OBJECTIVES

The aims of the study were to determine the predictive imaging findings of extranodal extension (ENE) in metastatic cervical lymph nodes of head and neck squamous cell carcinoma and to investigate the interobserver agreement among radiologists with different experience levels.

MATERIALS AND METHODS

Patients with cervical lymph node dissection and who had metastatic lymph nodes and preoperative imaging were included. Three radiologists evaluated nodal necrosis, irregular contour, gross invasion, and perinodal fat stranding. They also noted their overall impression regarding the presence of the ENE. Sensitivity, specificity, odds ratios based on logistic regression, and interobserver agreement of ENE status were calculated.

RESULTS

Of 106 lymph nodes (that met inclusion criteria), 31 had radiologically determined ENE. On pathologic examination, 22 of 31 nodes were positive for ENE. The increasing number of metastatic lymph nodes was associated with the presence of the ENE ( P = 0.010). Irregular contour had the highest sensitivity (78.6%) and gross invasion had the highest specificity (96%) for the determination of the ENE. The radiologists' impression regarding the presence of the pathlogical ENE had 39.3% sensitivity and 82% specificity. Metastatic lymph nodes with a perinodal fat stranding and with the longest diameter of greater than 2 cm were found to be strong predictors of the ENE. The gross invasion demonstrated the highest κ value (0.731) among the evaluated imaging criteria.

CONCLUSIONS

In the assessment of ENE, the gross invasion had the highest specificity among imaging features and showed the highest interobserver agreement. Perinodal fat stranding and the longest diameter of greater than 2 cm in a metastatic lymph node were the best predictors of the ENE.

Free-Breathing StarVIBE Sequence for the Detection of Extranodal Extension in Head and Neck Cancer: An Image Quality and Diagnostic Performance Study

(1) Background: This study aims to evaluate the image quality of abnormal cervical lymph nodes in head and neck cancer and the diagnostic performance of detecting extranodal extension (ENE) using free-breathing StarVIBE. (2) Methods: In this retrospective analysis, 80 consecutive head and neck cancer patients underwent StarVIBE before neck dissection at an academic center. Image quality was compared with conventional VIBE available for 28 of these patients. A total of 73 suspicious metastatic lymph nodes from 40 patients were found based on morphology and enhancement pattern on StarVIBE. Sensitivity (SN), specificity (SP), and odds ratios were calculated for each MR feature from StarVIBE to predict pathologic ENE. (3) Results: StarVIBE showed significantly superior image quality, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) for enlarged lymph nodes compared to VIBE. The MR findings of "invading adjacent planes" (SN, 0.54; SP, 1.00) and "matted nodes" (SN, 0.72; SP, 0.89) emerged as notable observations. The highest diagnostic performance was attained by combining these two features (SN, 0.93; SP, 0.89). (4) Conclusions: This study confirms that StarVIBE offers superior image quality for abnormal lymph nodes compared to VIBE, and it can accurately diagnose ENE by utilizing a composite MR criterion in head and neck cancer.

Clinical, Radiological and Histological Features and Their Association with Extranodal Extension in Buccoalveolar Complex Squamous Cell Carcinoma

Jeyashanth RijuObjectives  The study was aimed to (1) evaluate the effectiveness of clinical examination, intraoperative finding, and contrast-enhanced computed tomography (CECT) to detect extranodal extension (ENE) in buccoalveolar complex squamous cell carcinoma (BAOSCC), (2) to know various factors influencing ENE, and (3) to evaluate survival outcome in patients with ENE. Materials and Methods  This was a retrospective cohort study, which included 137 patients with BAOSCC who underwent curative treatment between May 2019 and April 2021. Collaborative findings suggestive of ENE were noted during preoperative clinical examination, CECT, and intraoperatively, and their efficacy was compared with postoperative histopathology. Also, the various factors associated with ENE were evaluated and compared. Statistical Analysis  Univariate and multivariate analysis of parameters was done using multiple logistic regression analysis and significant correlation was determined using chi-square test between ENE positive and negative categories. Analysis of prognosis and survival was done by Kaplan-Meier curve plotting using regression analysis and its significance was compared. Results  The overall prevalence of ENE was 18.98% and that of lymph node involvement was 40.88%. CECT (73.1%) was found to be more sensitive in detecting ENE compared to intraoperative examination (46.2%) and clinical examination (34.6%).In comparison with clinical examination (91.9%) or CECT (78.38%), intraoperative examination (93.7%) showed the highest specificity in detecting ENE. Clinical nodal size ≥ 3 cm ( p ≤ 0.001), fixity ( p ≤ 0.001), and clinical number of nodes ( p ≤ 0.001) had significant association with ENE. The presence of thick nodal walls on CECT increased the probability of predicting ENE 15 times ( p  = 0.180, confidence interval: 0.3-765.4). After a mean follow-up of 18 months, subjects without nodal positivity had a survival advantage over patients with positive lymph nodes (86.4% vs. 53.3%) and those with ENE (86.4% vs. 23.2%), respectively. Conclusion  The results demonstrated that clinical examination can be used as an adjuvant to radiological imaging for prediction of ENE preoperatively. Clinical finding suggesting size of node ≥ 3 cm and ≥ 2 nodes are strong predictor of ENE, in addition to other known predictors. Patients with ENE had an unfavorable prognosis when compared with subjects with metastatic nodes without ENE. Presence of ENE remains one of the strongest factors predicting recurrence and thus poor prognosis.

Diagnostic challenges and prognostic implications of extranodal extension in head and neck cancer: a state of the art review and gap analysis

Extranodal extension (ENE) is a pattern of cancer growth from within the lymph node (LN) outward into perinodal tissues, critically defined by disruption and penetration of the tumor through the entire thickness of the LN capsule. The presence of ENE is often associated with an aggressive cancer phenotype in various malignancies including head and neck squamous cell carcinoma (HNSCC). In HNSCC, ENE is associated with increased risk of distant metastasis and lower rates of locoregional control. ENE detected on histopathology (pathologic ENE; pENE) is now incorporated as a risk-stratification factor in human papillomavirus (HPV)-negative HNSCC in the eighth edition of the American Joint Committee on Cancer (AJCC) and the Union for International Cancer Control (UICC) TNM classification. Although ENE was first described almost a century ago, several issues remain unresolved, including lack of consensus on definitions, terminology, and widely accepted assessment criteria and grading systems for both pENE and ENE detected on radiological imaging (imaging-detected ENE; iENE). Moreover, there is conflicting data on the prognostic significance of iENE and pENE, particularly in the context of HPV-associated HNSCC. Herein, we review the existing literature on ENE in HNSCC, highlighting areas of controversy and identifying critical gaps requiring concerted research efforts.

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.

Assessment of Radiologic Extranodal Extension Using Combinatorial Analysis of Nodal Margin Breakdown and Metastatic Burden in Oropharyngeal Cancer

The importance of risk stratification in the management of oropharyngeal squamous cell carcinoma (OPSCC) is becoming increasingly obvious with the growing evidence of its variable prognosis. We identified and evaluated imaging characteristics predictive of extranodal extension (ENE) in OPSCC. Preoperative computed tomography and histopathologic results of 108 OPSCC patients who underwent neck dissection as primary treatment were analyzed. Imaging characteristics were reassessed for factors associated with nodal margin breakdown and metastatic burden. Moreover, the predictability of pathological ENE (pENE) was analyzed. Univariate and multivariate binomial logistic regression analyses were performed to examine the predictive power of ENE-related radiologic features. Imaging-based characteristics showed variable degrees of association with pENE. Factors associated with nodal margin breakdown (indistinct capsular contour, irregular margin, and perinodal fat stranding) and factors associated with nodal burden (nodal matting, lower neck metastasis, and presence of >4 lymph node metastases) were significantly predictive of ENE (odds ratio (OR) = 11.170 and 12.121, respectively). The combined utilization of the nodal margin and burden factors further increased the predictive ability (OR = 14.710). Factors associated with nodal margin breakdown and nodal burden were associated with pENE, demonstrating the use of combinatorial analysis for more accurate ENE prediction.

Screening for extranodal extension in HPV-associated oropharyngeal carcinoma: evaluation of a CT-based deep learning algorithm in patient data from a multicentre, randomised de-escalation trial

BACKGROUND

Pretreatment identification of pathological extranodal extension (ENE) would guide therapy de-escalation strategies for in human papillomavirus (HPV)-associated oropharyngeal carcinoma but is diagnostically challenging. ECOG-ACRIN Cancer Research Group E3311 was a multicentre trial wherein patients with HPV-associated oropharyngeal carcinoma were treated surgically and assigned to a pathological risk-based adjuvant strategy of observation, radiation, or concurrent chemoradiation. Despite protocol exclusion of patients with overt radiographic ENE, more than 30% had pathological ENE and required postoperative chemoradiation. We aimed to evaluate a CT-based deep learning algorithm for prediction of ENE in E3311, a diagnostically challenging cohort wherein algorithm use would be impactful in guiding decision-making.

METHODS

For this retrospective evaluation of deep learning algorithm performance, we obtained pretreatment CTs and corresponding surgical pathology reports from the multicentre, randomised de-escalation trial E3311. All enrolled patients on E3311 required pretreatment and diagnostic head and neck imaging; patients with radiographically overt ENE were excluded per study protocol. The lymph node with largest short-axis diameter and up to two additional nodes were segmented on each scan and annotated for ENE per pathology reports. Deep learning algorithm performance for ENE prediction was compared with four board-certified head and neck radiologists. The primary endpoint was the area under the curve (AUC) of the receiver operating characteristic.

FINDINGS

From 178 collected scans, 313 nodes were annotated: 71 (23%) with ENE in general, 39 (13%) with ENE larger than 1 mm ENE. The deep learning algorithm AUC for ENE classification was 0·86 (95% CI 0·82-0·90), outperforming all readers (p<0·0001 for each). Among radiologists, there was high variability in specificity (43-86%) and sensitivity (45-96%) with poor inter-reader agreement (κ 0·32). Matching the algorithm specificity to that of the reader with highest AUC (R2, false positive rate 22%) yielded improved sensitivity to 75% (+ 13%). Setting the algorithm false positive rate to 30% yielded 90% sensitivity. The algorithm showed improved performance compared with radiologists for ENE larger than 1 mm (p<0·0001) and in nodes with short-axis diameter 1 cm or larger.

INTERPRETATION

The deep learning algorithm outperformed experts in predicting pathological ENE on a challenging cohort of patients with HPV-associated oropharyngeal carcinoma from a randomised clinical trial. Deep learning algorithms should be evaluated prospectively as a treatment selection tool.

FUNDING

ECOG-ACRIN Cancer Research Group and the National Cancer Institute of the US National Institutes of Health.

Diagnostic performance of computed tomography features in detecting oropharyngeal squamous cell carcinoma extranodal extension

OBJECTIVES

Accurate pre-treatment imaging determination of extranodal extension (ENE) could facilitate the selection of appropriate initial therapy for HPV-positive oropharyngeal squamous cell carcinoma (HPV + OPSCC). Small studies have associated 7 CT features with ENE with varied results and agreement. This article seeks to determine the replicable diagnostic performance of these CT features for ENE.

METHODS

Five expert academic head/neck neuroradiologists from 5 institutions evaluate a single academic cancer center cohort of 75 consecutive HPV + OPSCC patients. In a web-based virtual laboratory for imaging research and education, the experts performed training on 7 published CT features associated with ENE and then independently identified the "single most (if any) suspicious" lymph node and presence/absence of each of the features. Inter-rater agreement was assessed using percentage agreement, Gwet's AC1, and Fleiss' kappa. Sensitivity, specificity, and positive and negative predictive values were calculated for each CT feature based on histologic ENE.

RESULTS

All 5 raters identified the same node in 52 cases (69%). In 15 cases (20%), at least one rater selected a node and at least one rater did not. In 8 cases (11%), all raters selected a node, but at least one rater selected a different node. Percentage agreement and Gwet's AC1 coefficients were > 0.80 for lesion identification, matted/conglomerated nodes, and central necrosis. Fleiss' kappa was always < 0.6. CT sensitivity for histologically confirmed ENE ranged 0.18-0.94, specificity 0.41-0.88, PPV 0.26-0.36, and NPV 0.78-0.96.

CONCLUSIONS

Previously described CT features appear to have poor reproducibility among expert head/neck neuroradiologists and poor predictive value for histologic ENE.

KEY POINTS

• Previously described CT imaging features appear to have poor reproducibility among expert head and neck subspecialized neuroradiologists as well as poor predictive value for histologic ENE. • Although it may still be appropriate to comment on the presence or absence of these CT features in imaging reports, the evidence indicates that caution is warranted when incorporating these features into clinical decision-making regarding the likelihood of ENE.

Unambiguous radiologic extranodal extension determined by MRI could be a biomarker in predicting metastatic prostate cancer

OBJECTIVE

To explore the relationship between unambiguous radiologic extranodal extension (rENE) and M1 staging in patients with metastatic PCa.

METHODS

A respective analysis of 1073 patients of PCa N1 staging from January 2004 to May 2022 was retrospectively enrolled. They were divided into rENE + and rENE -  groups and retrospectively analyzed the M staging with nuclear medicine data. The correlation index between unambiguous rENE and M1b staging was calculated. Logistic regression was used to evaluate the predictive performance of unambiguous rENE in M1b staging. ROC curves were used to investigate the relationship between unambiguous rENE and M staging in patients who underwent ⁶⁸ Ga-PSMA PET/CT.

RESULTS

A total of 1073 patients were included. Seven hundred and eighty patients were classified into the rENE + group (mean age, 69.6 years ± 8.7 [standard deviation]), and 293 were classified into rENE -  group (mean age, 66.7 years ± 9.4 [standard deviation]). Relationship between unambiguous rENE and M1b existed (r = 0.58, 95%CI: 0.52-0.64, P < 0.05). Unambiguous rENE could be an independent predictor for M1b (OR = 13.64, 95%CI: 9.23-20.14, P < 0.05). The AUC of unambiguous rENE in predicting M1b and M staging was 0.835 and 0.915, respectively, in patients who underwent ⁶⁸ Ga-PSMA PET/CT.

CONCLUSIONS

Unambiguous rENE could be a strong biomarker to predict M1b and M staging in patients with PCa. When rENE came up, patients should perform nuclear medicine immediately, and a systematic treatment should be considered.

Prediction of extranodal extension in oropharyngeal cancer patients and carcinoma of unknown primary: value of metabolic tumor imaging with hybrid PET compared with MRI and CT

OBJECTIVES

The aim of this study was to investigate the value of metabolic tumor imaging using hybrid PET for the preoperative detection of extranodal extension (ENE) in lymph node metastases of oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

We performed a retrospective analysis of a consecutive cohort of patients with OPSCC treated with primary surgery with or without adjuvant (chemo-) radiotherapy at the Kantonsspital Sankt-Gallen and the University Hospital Zurich, Switzerland, from 2010 until 2019. Hybrid PET was compared to conventional cross-sectional imaging with MRI and CT. Histopathological presence of ENE of neck dissection specimen served as gold standard.

RESULTS

A total number of 234 patients were included in the study, 95 (40.6%) of which had pathological ENE (pENE). CT has a good specificity with 93.7%; meanwhile, MRI was the most sensitive diagnostic method (72.0%). The nodal metabolic tumor parameters (SUV_max, TLG, MTV) were significantly higher in patients with positive ENE (p < 0.001 for all three parameters) than in patients with negative ENE (p < 0.001, for all three parameters).

CONCLUSIONS

CT achieved the best specificity, while MRI had the best sensitivity to detect ENE. Nodal metabolic tumor parameters differed significantly between ENE-positive/negative and p16-positive/negative patients. Hence, quantitative data obtained by metabolic imaging might predict presence of ENE and, therefore, could be helpful in customizing therapy management.

Optimized decision support for selection of transoral robotic surgery or (chemo)radiation therapy based on posttreatment swallowing toxicity

BACKGROUND

A primary goal in transoral robotic surgery (TORS) for oropharyngeal squamous cell cancer (OPSCC) survivors is to optimize swallowing function. However, the uncertainty in the outcomes of TORS including postoperative residual positive margin (PM) and extranodal extension (ENE), may necessitate adjuvant therapy, which may cause significant swallowing toxicity to survivors.

METHODS

A secondary analysis was performed on a prospective registry data with low- to intermediate-risk human papillomavirus-related OPSCC possibly resectable by TORS. Decision trees were developed to model the uncertainties in TORS compared with definitive radiation therapy (RT) and chemoradiation therapy (CRT). Swallowing toxicities were measured by Dynamic Imaging Grade of Swallowing Toxicity (DIGEST), MD Anderson Dysphagia Inventory (MDADI), and the MD Anderson Symptom Inventory-Head and Neck (MDASI-HN) instruments. The likelihoods of PM/ENE were varied to determine the thresholds within which each therapy remains optimal.

RESULTS

Compared with RT, TORS resulted in inferior swallowing function for moderate likelihoods of PM/ENE (>60% in short term for all instruments, >75% in long term for DIGEST and MDASI) leaving RT as the optimal treatment. Compared with CRT, TORS remained the optimal therapy based on MDADI and MDASI but showed inferior swallowing outcomes based on DIGEST for moderate-to-high likelihoods of PM/ENE (>75% for short-term and >40% for long-term outcomes).

CONCLUSION

In the absence of reliable estimation of postoperative PM/ENE concurrent with significant postoperative PM, the overall toxicity level in OPSCC patients undergoing TORS with adjuvant therapy may become more severe compared with patients receiving nonsurgical treatments thus advocating definitive (C)RT protocols.

Correlation between radiologic and pathologic extranodal extension in HPV-associated oropharyngeal cancer: Systematic review

Pretreatment determination of extranodal extension (ENE) has significant clinical implications in human papillomavirus positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC). Unfortunately there is no gold-standard imaging modality for radiological assessment of ENE in HPV+ OPSCC, leading to subjective assessments and complex decision making concerning ENE. A systematic review of diagnostic test accuracy was therefore undertaken, with five databases systemically searched to evaluate the diagnostic performance of an imaging modality for detection of ENE in HPV+ OPSCC. A meta-analysis was conducted on four CT studies using a random-effects model. While a narrative synthesis was provided for the studies using PET/CT and "CT and MRI." Out of 1772 hits, six studies were included in the review. Meta-analysis on four CT studies showed CT had an overall sensitivity of 77% and specificity of 60%. PET/CT had a sensitivity of 37.5% and specificity of 97%. "CT and MRI" had a sensitivity of 62% and specificity of 78%. Further diagnostic studies involving CT, PET/CT and MRI are ultimately required.

Prognostic Value of Radiological Extranodal Extension Detected by Computed Tomography for Predicting Outcomes in Patients With Locally Advanced Head and Neck Squamous Cell Cancer Treated With Radical Concurrent Chemoradiotherapy

Objective

Extra Nodal Extension (ENE) assessment in locally advanced head and neck cancers (LAHNCC) treated with concurrent chemo radiotherapy (CCRT) is challenging and hence the American Joint Committee on Cancer (AJCC) N staging. We hypothesized that radiology-based ENE (rENE) may directly impact outcomes in LAHNSCC treated with radical CCRT.

Materials and Methods

Open-label, investigator-initiated, randomized controlled trial (RCT) (2012–2018), which included LAHNSCC planned for CCRT. Patients were randomized 1:1 to radical radiotherapy (66–70 grays) with concurrent weekly cisplatin (30 mg/m²) [cisplatin radiation arm (CRT)] or same schedule of CRT with weekly nimotuzumab (200 mg) [nimotuzumab plus CRT (NCRT)]. A total of 536 patients were accrued and 182 were excluded due to the non-availability of Digital Imaging and Communications in Medicine (DICOM) computed tomography (CT) data. A total of 354 patients were analyzed for rENE. Metastatic nodes were evaluated based on five criteria and further classified as rENE as positive/negative based on three-criteria capsule irregularity with fat stranding, fat invasion, and muscle/vessel invasion. We evaluated the association of rENE and disease-free survival (DFS), loco-regional recurrence-free survival (LRRFS), and overall survival (OS).

Results

A total of 244 (68.9%) patients had radiologically metastatic nodes (rN), out of which 140 (57.3%) had rENE. Distribution of rENE was balanced in the two study groups CRT or NCRT (p-value 0.412). The median follow-up period was 39 months (ranging from 35.5 to 42.8 months). Complete response (CR) was seen in 204 (57.6%); incomplete response (IR), i.e., partial response plus stable disease (PR + SD), in 126 (35.6%); and progressive disease (PD) in 24 (6.8%). rENE-positive group had poor survival compared to rENE-negative group 3-year OS (46.7% vs. 63.6%), poor DFS (48.8% vs. 87%), and LRRFS (39.9% vs. 60.4%). rENE positive had 1.71 times increased risk of IR than rENE negative. Overall stage, site, clinical metastatic node (cN), response, and rENE were the significant factors for predicting OS, DFS, and LRRFS on univariate analysis. After making adjustment on multivariate analysis, rENE was an independent prognostic factor for DFS and trending to be significant for OS.

Conclusion

Pre-treatment rENE is an independent prognostic marker for survival in patients with LAHNSCC treated radically with CCRT that can be used as a potential predictive marker for response to treatment and hence stratify patients into responders vs. non-responders. We propose the mahajan rENE grading system applicable on CT, magnetic resonance imaging, positron emission tomography–contrast-enhanced CT, and ultrasound.

Prognostic impact of matted lymphadenopathy in patients with oropharyngeal squamous cell carcinoma treated with definitive chemoradiotherapy

OBJECTIVE

To determine whether cervical matted lymphadenopathy (ML) is associated with outcomes in patients with oropharyngeal squamous cell carcinoma (OPSCC) treated with definitive chemoradiotherapy (CRT).

MATERIALS AND METHODS

OPSCC patients treated at our institution with CRT were included (n = 417). ML was defined by three adjacent nodes without an intervening fat plane. Patients were stratified into favorable OPSCC (p16 + with ≤ 10 pack-years smoking history) or unfavorable OPSCC (p16- and/or > 10 pack years). Primary outcomes were overall survival (OS) and progression-free survival (PFS) and the cumulative incidences of regional recurrence (RR) and distant metastasis (DM).

RESULTS

The median follow-up time for the surviving cohort was 49.9 months. In favorable OPSCC (n = 220), there were no significant associations between ML and any outcome. In unfavorable OPSCC (n = 197), ML had a significant negative impact on OS and PFS, with 3-year OS for patients without and with matted nodes at 74% and 56% (HR, 1.61, 95% CI 1.01-2.58). On multivariable Cox regression, patients with ML experienced significantly worsened OS (HR 1.65, 95% CI 1.03-2.65) and PFS (HR 1.94, 95% CI 1.28-2.93). The cumulative incidence of DM was also higher with ML (31% vs. 9%, adjusted HR 3.3, 95% CI 1.71-6.48).

CONCLUSION

ML carries no prognostic importance in patients with favorable OPSCC. However, ML portends significantly worse outcomes in individuals with HPV-negative disease or a significant smoking history. Thus, ML may help risk-stratify this latter population for treatment intensification, but does not seem to be a contraindication for treatment de-escalation in the former.

Risk of Pathologic Extranodal Extension and Other Adverse Features After Transoral Robotic Surgery in Patients With HPV-Positive Oropharynx Cancer

Importance

Understanding patient-specific risk of adverse histopathologic findings after primary surgery for human papillomavirus (HPV)-positive oropharynx squamous cell carcinoma (OPSCC) may help guide patient consultations.

Objective

To determine the likelihood of adverse histopathologic features that may indicate adjuvant radiotherapy or chemoradiotherapy after primary surgery for HPV-positive OPSCC according to 2021 National Comprehensive Cancer Network guidelines.

Design, Setting, and Participants

This retrospective cohort study was performed at a single academic tertiary care center. Of 258 patients who underwent transoral robotic surgery (TORS) from March 1, 2012, to March 1, 2021, 136 consecutive, treatment-naive patients with HPV-positive OPSCC without obvious clinical extranodal extension (ENE) who underwent definitive TORS and neck dissection were included in the analysis. Indications for surgical treatment included non-deeply infiltrative oropharynx tumors, minimal soft palate involvement, and low suspicion for pathologic ENE.

Exposures

Primary site TORS with neck dissection.

Main Outcomes and Measures

The primary outcomes were the adverse histopathologic features of pathologic ENE and positive surgical margins (PSM) that are indications for possible adjuvant chemoradiotherapy. Outcomes were compared among varying American Joint Committee on Cancer 7th edition (AJCC-7) T and N categories and patient clinical characteristics.

Results

Of the 136 patients included in the analysis (113 men [83.1%]; median age, 63 [interquartile range, 55-70] years), 109 (80.1%) had at least 1 indication for possible adjuvant radiotherapy. Twenty-seven patients (19.9%) had pathologic ENE and 10 (7.3%) had PSM. Thirty-four patients (25.0%) had pathologic ENE and/or PSM, whereas 3 (2.2%) had both. Age, smoking history, history of alcohol consumption, and clinical T category were not associated with pathologic ENE, PSM, lymphovascular invasion, perineural invasion, or pN2 category or greater. The proportion of pathologic ENE varied by clinical N category: 0 of 16 for cN0, 8 of 48 (16.7%) for cN1, 3 of 23 (13.0%) for cN2a, and 16 of 45 (35.6%) for cN2b. Compared with patients with cN1-cN2a disease, patients with cN2b disease had higher odds of pathologic ENE (odds ratio, 3.01; 95% CI, 1.14-8.10). Clinical and pathologic N category were concordant in 77 patients (56.6%), whereas 42 (30.9%) were upstaged and 17 (12.5%) were downstaged.

Conclusions and Relevance

In this cohort study, approximately one-quarter of carefully selected patients with HPV-positive OPSCC without obvious clinical ENE undergoing primary surgery had pathologic ENE and/or PSM. Patients with AJCC-7 cT0-cT2 cN0-cN2b disease, especially cN0-cN2a, without signs of clinical ENE may represent appropriate candidates for primary surgery when avoidance of adjuvant chemotherapy and/or reduction of adjuvant radiotherapy dose/extent are the goals.

Advances in Imaging for HPV-Related Oropharyngeal Cancer: Applications to Radiation Oncology

While there has been an overall decline of tobacco and alcohol-related head and neck cancer in recent decades, there has been an increased incidence of HPV-associated oropharyngeal cancer (OPC). Recent research studies and clinical trials have revealed that the cancer biology and clinical progression of HPV-positive OPC is unique relative to its HPV-negative counterparts. HPV-positive OPC is associated with higher rates of disease control following definitive treatment when compared to HPV-negative OPC. Thus, these conditions should be considered unique diseases with regards to treatment strategies and survival. In order to sufficiently characterize HPV-positive OPC and guide treatment strategies, there has been a considerable effort to diagnose, prognose, and track the treatment response of HPV-associated OPC through advanced imaging research. Furthermore, HPV-positive OPC patients are prime candidates for radiation de-escalation protocols, which will ideally reduce toxicities associated with radiation therapy and has prompted additional imaging research to detect radiation-induced changes in organs at risk. This manuscript reviews the various imaging modalities and current strategies for tackling these challenges as well as provides commentary on the potential successes and suggested improvements for the optimal treatment of these tumors.

Assessment Criteria and Clinical Implications of Extranodal Extension in Head and Neck Cancer

Tumor breaching the capsule of a lymph node is termed extranodal extension (ENE). It reflects aggressiveness of a tumor, creates anatomic challenges for disease clearance, and increases the risk of distant metastasis. Extranodal extension can be assessed on a pathology specimen, by radiology studies, and by clinical examination. Presence of ENE in a pathology specimen has long been considered a high-risk feature of disease progression and would ordinarily benefit from the addition of chemotherapy to adjuvant radiotherapy. Although the eighth edition of the Union for International Cancer Control/American Joint Committee on Cancer stage classification dichotomizes pathologic ENE according to its presence or absence, emerging evidence suggests that the extent of a pathologic ENE may provide additional value for risk stratification to guide adjuvant therapy. Recent data suggest that the prognostic importance of pathologic ENE is also applicable for HPV-associated head and neck squamous cell carcinoma. In addition, compelling data demonstrate that indisputable radiologic ENE is a powerful risk stratification tool to identify patients at high risk for treatment failure, especially distant metastasis, applicable for both HPV-positive and HPV-negative head and neck squamous cell carcinoma. However, the definition and taxonomy of radiologic ENE requires standardization. The goal of this review is to clarify the contemporary understanding of the prognostic implications of ENE in head and neck squamous cell carcinoma, present the nuances of what is presently known and unknown, and elucidate how to classify ENE pathologically and radiologically with an understanding of the strengths and weaknesses of each approach. Finally, with the development of several risk stratification methods, the relative role of ENE and other prognostic schema will be explored.

Accuracy of the Anatomage Table in detecting extranodal extension in head and neck cancer: a pilot study

Purpose: To assess whether the three-dimensional reconstructions of preoperative computed tomography (CT) scans are helpful for establishing extranodal extension (ENE) in head and neck carcinoma. Approach: Patients with a histological diagnosis of ENE ( pENE + ) were considered "cases" and patients with negative histological examination for ENE ( pENE - ) were considered "controls." Cases and controls were divided into two groups: a major nodes (MaN) group (lymph nodes on CT > 15    mm ) and a minor nodes (MiN) group (lymph nodes on CT ≤ 15    mm ). The preoperative CT scans were uploaded to the Anatomage Table and were randomly and blindly provided to the radiologist for assessment. The findings at the Anatomage Table were compared with those of CT and magnetic resonance imaging (MRI) scans. Results: Analysis of data from the MaN group showed that the Anatomage Table had a higher percentage of concordance with histopathological examination (90%) than the CT and MRI scans. The Anatomage Table had 100% sensitivity in identifying all pENE + patients, associated with a lower specificity. The negative predictive value of 100% allowed identification of pENE - patients. In the MiN group, on the other hand, sensitivity was lower, related to a high number of false-negative results. Conclusions: The Anatomage Table could represent a useful tool for preoperatively establishing the extranodal extension of cervical lymph node metastasis.

Prognostic value of clinical and radiologic extranodal extension and their role in the 8th edition TNM cN classification for HPV-negative oropharyngeal carcinoma

BACKGROUND/OBJECTIVES

We evaluate the performance between the TNM-8 versus TNM-7 cN-classification and explore the relative prognostic contribution of radiologic extranodal extension (rENE) for HPV-negative oropharyngeal cancer (HPV-OPC).

MATERIALS/METHODS

All HPV- OPC treated with IMRT between 2005 and 2016 were included. cENE was defined as unambiguous "fixation" of a neck mass or "skin involvement" on clinical examination. rENE was recorded by re-reviewing pre-treatment CT/MR. Disease-free survival (DFS) stratified by cENE or rENE were compared. Multivariable analyses (MVA) calculated the adjusted hazard ratio (aHR) for the separate cENE and rENE attributes and their combination. A refined cN-category incorporating both cENE and rENE parameters was proposed. The performance of the revision was compared to TNM-8 and TNM-7.

RESULTS

Of 361 HPV- OPC, 97 were cN0 and 264 were cN+ with 48 cENE+ and 72 rENE+ respectively. Median follow-up was 5.4 years. The 3-year DFS was lower in cENE+ vs cENE-negative (cENE-) (23% vs 45%; aHR = 1.68, p = 0.008) and rENE+ vs rENE-negative (rENE-) patients (29% vs 45%; aHR = 1.44, p = 0.037). The cENE+/rENE+ subset had the worse DFS vs cENE-/rENE+ or cENE-/rENE- (24%/37%/46%, p = 0.005). We propose a refined cN-category wherein any cENE-/rENE+ case is reclassified one N-stratum higher while any cENE+ case remains cN3b. The stage schema with the refined N-categorization outperformed TNM-8, and both outperformed TNM-7.

CONCLUSIONS

cENE and rENE are both prognostic but the cENE+/rENE+ subset has the worst outcome. The TNM-8 cN-categories improves outcome prediction compared to the TNM-7. Incorporation of rENE into TNM-8 cN-categories may further augment performance.

Predicting Adverse Histopathology and Need for Postsurgical Adjuvant Therapy for Human Papilloma Virus-Associated Oropharynx Carcinoma

OBJECTIVE

For human papillomavirus-associated oropharynx carcinoma treated with definitive surgery, we aimed to find predictors of adverse histopathology indicating the possible need for adjuvant therapy.

STUDY DESIGN

Retrospective review.

SETTING

National Cancer Database.

METHODS

We analyzed 2347 eligible patients from 2010 to 2015. We evaluated (1) the ability of clinical nodal staging and extranodal extension designation per the AJCC, seventh edition (American Joint Committee on Cancer), to predict histopathology and (2) the likelihoods for adverse postsurgery histopathology by common clinical stages.

RESULTS

Clinical nodal staging predicted pathologic nodal staging 65% of the time, with 24% (569/2347) being upstaged and 11% (251/2347) being downstaged. In patients with cN+ disease, clinical extranodal extension distinction had the following accuracy for pathologic extranodal extension: positive predictive value, 81% (88/109); negative predictive value, 73.1% (505/691); sensitivity, 32.1% (88/274); and specificity, 96.0% (505/526). Patients with cT1-2, N0-N2c, without clinical extranodal extension had the following proportions of pN2+ without pathologic extranodal extension (indicating consideration for adjuvant radiation): cN0, 11%; cN1, 31%; cN2a, 67% (8% downstaged); cN2b, 66% (6% downstaged); and cN2c, 35% (17% downstaged). From this group, patients had the following proportions of pathologic extranodal extension (indicating consideration for adjuvant chemoradiation): cN0, 6%; cN1, 20%; cN2a, 27%; cN2b, 28%; and cN2c, 48%.

CONCLUSION

For human papillomavirus-associated oropharynx carcinoma, nodal clinical staging per the American Joint Committee on Cancer, seventh edition, predicts pathologic stage about two-thirds of the time, leading to up- and downstaging. Clinical extranodal extension assessment has low sensitivity and moderate predictive capability. With careful selection, definitive surgery can allow patients to often avoid adjuvant chemotherapy and sometimes avoid adjuvant radiation.

The diagnostic performance of CT and MRI for detecting extranodal extension in patients with head and neck squamous cell carcinoma: a systematic review and diagnostic meta-analysis

OBJECTIVE

To review the diagnostic performance of CT and MRI for detecting extranodal extension (ENE) in head and neck squamous cell carcinoma (HNSCC) patients.

METHODS

MEDLINE and EMBASE databases were searched up to October 7, 2019. Studies that evaluated the diagnostic performance of CT and/or MRI for detecting ENE in HNSCC patients were included. A 2 × 2 table was reconstructed for each study. Pooled sensitivity and specificity were calculated using the bivariate model and hierarchical summary receiver operating characteristic (HSROC) model. Subgroup analyses were performed according to HPV status and radiological features. Pooled correlation coefficient for interobserver agreement was calculated.

RESULTS

Twenty-two studies including 2478 patients were included. The pooled sensitivity and specificity for detecting ENE were 73% (95% CI, 62-82%) and 83% (95% CI, 75-89%), respectively, for CT, and 60% (95% CI, 49-70%) and 96% (95% CI, 85-99%), respectively, for MRI. There was substantial heterogeneity for both CT and MRI. A threshold effect was present for MRI. On subgroup analysis, the pooled specificity of CT was significantly lower in patients with HPV+ OPSCC than in patients with HPV‑ oral cavity cancer or all HNSCC (74% vs. 87%; p = 0.01). Central node necrosis showed significantly higher pooled sensitivity (81% vs. 51%; p = 0.02), while infiltration of adjacent planes showed significantly higher pooled specificity (94% vs. 65%; p = 0.03). The pooled correlation coefficient was 0.72 (95% CI, 0.60-0.81).

CONCLUSION

Both CT and MRI show reasonable diagnostic performance for detecting ENE in HNSCC patients and interobserver agreement was substantial.

KEY POINTS

• Pooled sensitivity and specificity were 73% and 83% for CT and 60% and 96% for MRI without significant difference. • Pooled specificity was lower for HPV+ OPSCC than for HPV‑ oral cavity cancer or all HNSCC (74% vs. 87%, p = 0.01), likely due to central node necrosis. • Central node necrosis showed higher sensitivity (81% vs. 51%; p = 0.02), while infiltration of adjacent planes showed higher specificity (94% vs. 65%; p = 0.03).

Prognostic Value of Nodal Matting on MRI in Nasopharyngeal Carcinoma Patients

BACKGROUND

Nodal (N) stage is one of the most important predictors for distant metastasis in nasopharyngeal carcinoma (NPC) patients. It may ignore potentially useful nodal features, such as nodal matting (three or more lymph nodes abutting together with the absence of intervening fat planes).

PURPOSE

To explore the prognostic value of nodal matting in NPC patients and construct a nomogram with nodal matting for predicting distant metastasis-free survival (DMFS).

STUDY TYPE

Retrospective.

POPULATION

In all, 792 NPC patients treated with intensity modulated radiation therapy from 2010 to 2013 were enrolled with 2:1 training (n = 527) and validation (n = 65) cohorts.

FIELD STRENGTH/SEQUENCE

T₁ - and T₂ -weighted imaging at 1.5 or 3.0T.

ASSESSMENT

Nodal matting and other nodal characteristics were assessed with MRI. MR images were evaluated separately by three radiologists. The association between nodal matting and DMFS was analyzed.

STATISTICAL TESTS

Univariate and multivariate analyses were performed using the Cox proportional hazards regression model. Nomograms were constructed from a multivariate logistic regression model with and without nodal matting. The predictive accuracy and discriminative ability of the nomograms were determined by concordance index (C-index) and calibration curves. The results were validated using bootstrap resampling and validation cohort.

RESULTS

The incidence of nodal matting was 24.6% (195/792) in all patients. In the training cohort, nodal matting was independently associated with DMFS (hazard ratio [HR] = 1.97 [1.05-3.69], P < 0.05). N1 patients with nodal matting had worse DMFS than N1 patients without (P < 0.05). However, no significant difference was observed when comparing N1 patients with nodal matting to N2 patients (P = 0.464). The C-index of the nomogram with nodal matting was higher than the nomogram without (0.717 vs. 0.699, P = 0.084).

DATA CONCLUSION

Nodal matting was an independent prognostic factor for DMFS in NPC patients. It may help to select patients at high risk of distant metastasis.

Significance of Extranodal Extension in Surgically Treated HPV-Positive Oropharyngeal Carcinomas

Squamous cell carcinomas of the head and neck are the subject of numerous current studies, especially in view of the increasing incidence of tumors induced by human papillomavirus (HPV) and the latest changes to the TNM classification of oropharyngeal squamous cell carcinoma (OPSCC). In addition to HPV status, the presence of extranodal extension of lymph node metastases represents an important risk and prognostic factor, which has now been integrated into the staging algorithm of the eighth edition of TNM classification for HPV-negative OPSCC. In the past numerous studies had shown a lack of prognostic significance of extranodal extension in HPV-associated tumors. However, extranodal extension–as a possible risk factor even in HPV-positive OPSCC–remains an important subject of current studies, which are now particularly characterized by high numbers of cases. In this paper, diagnostic methods and the prognostic significance of extranodal extension in surgically treated HPV-positive OPSCC are presented and discussed based on relevant literature, and the results of current publications are summarized. Further development of diagnostic criteria and procedures as well as international standardization of clinical diagnostics of extranodal extension should be encouraged. Several studies demonstrate that extranodal extension results in worse survival outcomes even in HPV-positive tumors, in contrast to results of previous studies. Consequently, whether the prognostic significance of extranodal extension is not actually relevant to outcome and the staging algorithm of HPV-positive OPSCC should be questioned and further analyzed.