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

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.

Identification of clinical and pathologic features associated with extranodal extension in patients with HPV-mediated oropharyngeal squamous cell carcinoma

BACKGROUND

Extranodal extension (ENE) is an important prognostic factor that is not ascertainable prior to surgical resection of involved lymph node(s) or may not be available in patients with prior excisional biopsies.

METHODS

This study involved a retrospective analysis of 900 patients diagnosed with HPV(+)OPSCC and treated with primary surgery at a single tertiary care center. Patient demographics, comorbidities, and pathologic characteristics of disease were collected and analyzed. Pathology reports were reviewed to identify ENE. Univariate and multivariate logistic regression models were used to identify factors associated with odds of ENE.

RESULTS

ENE was identified in 506/900 (56.2 %) patients. On univariate analysis, increased Adult Comorbidity Evaluation - 27 (p = 0.013), pathologic T-stage (p = 0.012), pathologic N-stage (p < 0.001), count of involved nodes (p < 0.001), size of largest involved node (p < 0.001), and perineural invasion (p = 0.001) were found to be positively associated with increased odds of ENE. On multivariate analysis, count of involved nodes (p < 0.001), size of largest involved node (p < 0.001), and perineural invasion (p = 0.021) were positively associated with increased odds of ENE. Although PNI improved the model's predictive performance statistically, its exclusion produced similar results. Both predictive models have been made publicly available (https://rtools.mayo.edu/prime_ene_prediction/).

CONCLUSION

Increased count of involved lymph nodes, size of largest involved lymph node, and presence of perineural invasion in patients with HPV(+)OPSCC are strongly associated with increased odds of ENE. These data suggest that ENE presence can be reliably predicted using the number and size of involved nodes. Such a predictive model could prove a useful tool in informing treatment strategies for HPV(+)OPSCC patients prior to surgical resection of involved lymph node(s) and those without sufficient pathologic ENE data from prior excisional biopsies.

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.

Recurrence Detection by Hybrid [ 18F]FDG-PET in Advanced Head and Neck Squamous Cell Carcinoma

BACKGROUND

In the clinical management of advanced stage head and neck squamous cell carcinoma, the use of hybrid [18F]FDG-PET imaging is well established. However, there is ongoing debate regarding the optimal frequency of hybrid PET scans to be included in follow-up protocols, particularly if the initial post-therapeutic scan is negative.

METHODS

We conducted a single-center 10-year retrospective study involving all patients who underwent hybrid PET scans for the follow-up of advanced stage head and neck cancer. A total of 285 patients were included.

RESULTS

Out of 199 patients with a negative 3-month hybrid PET, 15% subsequently developed a recurrence during further follow-up. Notably, 90% of these recurrences were detected by hybrid PET.

CONCLUSION

Fifteen percent of patients with a negative 3-month hybrid PET experienced a recurrence. Given that the majority of recurrences were detected by hybrid PET scans, there is a compelling argument for incorporating regular repetitive scans during follow-up.

Imaging Findings of Human Papillomavirus-Positive and Human Papillomavirus-Negative Oropharyngeal Squamous Cell Carcinoma Associated with Recurrence

Objectives: This study aimed to compare the imaging findings associated with the recurrence of HPV-positive and HPV-negative oropharyngeal squamous cell carcinoma (OPSCC). Methods: In total, 68 patients (51 men; mean age, 64.4 years; age range, 41-86 years; 48 HPV-positive patients and 20 HPV-negative patients) with histopathologically proven OPSCC who underwent CT, MRI, and 18F-FDG-PET/CT before treatment between October 2014 and July 2022 were enrolled in this study. The imaging findings were retrospectively evaluated and statistically compared. Results: HPV-positive OPSCC had a significantly lower recurrence rate compared with that of HPV-negative OPSCC (p < 0.01). Among HPV-positive OPSCCs, patients with recurrence were considerably older than those without recurrence (p < 0.05); however, the T and N categories did not differ between the two groups. Meanwhile, among HPV-negative OPSCCs, the T and N categories were associated with recurrence (p < 0.05). Furthermore, the attenuation on contrast-enhanced CT (p < 0.05) and signal intensity on contrast-enhanced T1-weighted images (p < 0.05) of nodal metastases were significantly lower in recurrence patients compared to those in nonrecurrence patients. Cystic change in nodal metastases in HPV-positive and HPV-negative OPSCCs were similar in patients with and without recurrence. Conclusions: The T and N categories were associated with recurrence in HPV-negative OPSCC but not in HPV-positive OPSCC. Prognostic factors differed significantly between HPV-positive and HPV-negative OPSCC.

[Advances in the diagnosis and prognosis of extranodal extension in head and neck squamous cell carcinoma]

Objective:The extranodal extension（ENE） is widely found in head and neck squamous cell carcinoma（HNSCC）, which displays the aggressiveness of the tumor and increasing the risk of local recurrence and distant metastasis, so the ENE often has been used as an important indicator of prognosis and treatment. Although the pathologic and radiologic tests are currently the main diagnostic techniques for ENE, there is still a lack of uniform standards. The article reviews the prognostic value, pathologic and radiologic diagnosis of ENE in HNSCC over the recent years.

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.

Upfront Neck Dissection for Treatment Selection and Improvement in Quality of Life as a Novel Treatment Paradigm for Deintensification in HPV+ OPSCC

PURPOSE

Locoregionally advanced HPV+ oropharyngeal squamous cell carcinoma (OPSCC) has excellent cure rates, although current treatment regimens are accompanied by acute and long-term toxicities. We designed a phase II deescalation trial for patients with HPV+ OPSCC to evaluate the feasibility of an upfront neck dissection to individualize definitive treatment selection to improve the quality of life without compromising survival.

PATIENTS AND METHODS

Patients with T1-3, N0-2 HPV+ OPSCC underwent an upfront neck dissection with primary tumor biopsy. Arm A included patients with a single lymph node less than six centimeters, with no extracapsular spread (ECS) and no primary site adverse features underwent transoral surgery. Arm B included patients who had two or more positive lymph nodes with no ECS, or those with primary site adverse features were treated with radiation alone. Arm C included patients who had ECS in any lymph node and were treated with chemoradiation. The primary endpoint was quality of life at 1 year compared with a matched historical control.

RESULTS

Thirty-four patients were enrolled and underwent selective neck dissection. On the basis of pathologic characteristics, 14 patients were assigned to arm A, 10 patients to arm B, and 9 to arm C. A significant improvement was observed in Head and Neck Quality of Life (HNQOL) compared with historical controls (-2.6 vs. -11.9, P = 0.034). With a median follow-up of 37 months, the 3-year overall survival was 100% and estimated 3-year estimated progression-free survival was 96% [95% confidence interval (CI), 76%-99%].

CONCLUSIONS

A neck dissection-driven treatment paradigm warrants further research as a deintensification strategy.

The prognostic effect of radiological extranodal extension in HPV-positive oropharyngeal squamous cell carcinomas: a retrospective cohort analysis

PURPOSE

Radiological extranodal extension (rENE) is a well-known negative prognosticator in head and neck squamous cell carcinoma (HNSCC). However, controversy remains regarding the prognostic effect of rENE in HPV-positive oropharyngeal SCCs (OPSCC). This single-center retrospective cohort analysis assessed the prognostic role of rENE in an HPV + OPSCC population and tried to validate a recently proposed modification of the TNM8 N-classification.

METHODS

129 patients with HPV + OPSCC, of whom 106 cN + patients, were included. Radiological imaging (CT, MRI or both) was reanalyzed by a senior head and neck radiologist. Overall survival (OS), disease-free survival (DFS), locoregional recurrence-free survival (LRFS), and disease-specific survival (DSS) were evaluated. Cox proportional hazard models were used for estimating hazard ratios (HR).

RESULTS

A non-significant trend towards better outcomes in the rENE- group, as compared to the rENE + population, was observed for 5 year OS [80.99% vs 68.70%, HR: 2.05, p = 0.160], 5 year RFS [78.81% vs 67.87%, HR: 1.91, p = 0.165], 5 year DFS [77.06% vs 60.16%, HR: 2.12, p = 0.0824] and 5 year DSS [88.83% vs 81.93%, HR: 2.09, p = 0.195]. OS declined with ascending levels of rENE (p = 0.020). Multivariate analysis identified cT-classification and smoking as independent negative predictors for OS/DFS. The proposed modification of the TNM8 N-classification could not be validated.

CONCLUSIONS

Although rENE could not be identified as an independent negative prognosticator for outcome in our HPV + OPSCC population, outcomes tend to deteriorate with increasing rENE.

Extra-Capsular Spread of Lymph Node Metastasis in Oral, Oropharyngeal and Hypopharyngeal Cancer: A Comparative Subsite Analysis

BACKGROUND

The extra-capsular spread (ECS) of lymph node metastasis (LNM) is a hallmark of aggressive primary tumor phenotype in head and neck cancer (HNC); however, the factors influencing ECS are poorly understood.

PATIENTS AND METHODS

This was a retrospective study, including 190 cases of oral tongue cancer (OTC), 148 cases of oropharyngeal cancer (OPC) (118 HPV-positive and 30 HPV-negative), and 100 cases of hypopharyngeal cancer (HPC). Tumor dimension, tumor biological variables (lymphovascular/perineural invasion and histologic grade), and LNM variables (LNM number and size) were analyzed according to the presence of ECS using multivariable logistic regression and receiver operating characteristic (ROC) curve analyses.

RESULTS

LNM variables were significant factors for ECS in all subsites of HNC (p < 0.05), except HPV-positive OPC. In OTC, tumor dimensional variables were significantly related to ECS (p < 0.01). Meanwhile, in OPC and HPC, neither the primary tumor dimension nor the T status were significant factors for ECS occurrence. The predictability of ECS by ROC curve using multiple variables was 0.819 [95% confidence interval: 0.759-0.878] in OTC, 0.687 [0.559-0.815] in HPV-positive OPC, 0.823 [0.642-1.000] in HPV-negative OPC, and 0.907 [0.841-0.973] in HPC.

CONCLUSION

LNM variables were correlated with ECS occurrence for most HNC subsites, and site-dependent primary tumor characteristics might contribute differentially to the ECS development of LNM in HNC.