Surveillance imaging following treatment of head and neck cancer

Imaging of the Posttreatment Head and Neck: Expected Findings and Potential Complications

Interpretation of posttreatment imaging findings in patients with head and neck cancer can pose a substantial challenge. Malignancies in this region are often managed through surgery, radiation therapy, chemotherapy, and newer approaches like immunotherapy. After treatment, patients may experience various expected changes, including mucositis, soft-tissue inflammation, laryngeal edema, and salivary gland inflammation. Imaging techniques such as CT, MRI, and PET scans help differentiate these changes from tumor recurrence. Complications such as osteoradionecrosis, chondroradionecrosis, and radiation-induced vasculopathy can arise because of radiation effects. Radiation-induced malignancies may occur in the delayed setting. This review article emphasizes the importance of posttreatment surveillance imaging to ensure proper care of patients with head and neck cancer and highlights the complexities in distinguishing between expected treatment effects and potential complications. Keywords: CT, MR Imaging, Radiation Therapy, Ear/Nose/Throat, Head/Neck, Nervous-Peripheral, Bone Marrow, Calvarium, Carotid Arteries, Jaw, Face, Larynx © RSNA, 2024.

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.

Ultrasound Is Beneficial to Determine Lymphadenopathy in Oral Cancer Patients after Radiotherapy

The present study aimed to investigate whether the addition of ultrasound (US) +/- fine needle aspiration (FNA) to magnetic resonance imaging (MRI) or computed tomography (CT) improves the diagnostic accuracy in assessing neck lymphadenopathy in oral cancer patients after neck irradiation. We retrospectively reviewed oral cancer patients who had neck lymphadenopathy after radiotherapy (RT) or chemoradiation therapy (CRT) from February 2008 to November 2019. The following diagnostic modalities were assessed: (1) MRI/CT, (2) MRI/CT with a post-RT US predictive model, and (3) MRI/CT with US + FNA. The receiver operating characteristic (ROC) curves were used to assess the diagnostic performance. A total of 104 irradiation-treated oral cancer patients who subsequently had neck lymphadenopathy were recruited and analyzed. Finally, there were 68 (65%) malignant and 36 (35%) benign lymphadenopathies. In terms of the diagnostic performance, the area under the ROC curves (C-statistics) was 0.983, 0.920, and 0.828 for MRI/CT with US + FNA, MRI/CT with a post-RT US predictive model, and MRI/CT, respectively. The addition of US to MRI/CT to evaluate cervical lymphadenopathy could achieve a better diagnostic accuracy than MRI/CT alone in oral cancer patients after neck irradiation.

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.

Ultrasound examination supporting CT or MRI in the evaluation of cervical lymphadenopathy in patients with irradiation-treated head and neck cancer

In this study, we determined the diagnostic performance of adding ultrasound (US) with/without fine-needle aspiration cytology (FNAC) to computed tomography (CT)/magnetic resonance imaging (MRI) in evaluating neck lymphadenopathy (LAP) in patients with head and neck cancer treated with irradiation. We included 269 patients who had neck LAP after radiotherapy (RT) or concurrent chemoradiotherapy (CCRT) resulting from cancers of the head and neck region between October 2008 and September 2018. The diagnostic methods consisted of the following: 1) CT/MRI alone, 2) CT/MRI combined with a post-RT US predictive model, and 3) CT/MRI combined with US + FNAC. We compared their diagnostic performance using receiver operating characteristic (ROC) curves. In total, 141 (52%) malignant and 128 (48%) benign LAPs were observed. Regarding the diagnostic accuracy, the area under the ROC curves was highest for the combined CT/MRI and US + FNAC (0.965), followed by the combined CT/MRI and post-RT US predictive model (0.906) and CT/MRI alone (0.836). Our data suggest that the addition of a US examination to CT/MRI resulted in higher diagnostic performance than CT/MRI alone in terms of diagnosing recurrent or persistent nodal disease during the evaluation of LAP in patients with irradiation-treated head and neck cancer.

Systematic review and meta-analysis of the diagnostic effectiveness of positron emission tomography-computed tomography versus magnetic resonance imaging in the post-treatment surveillance of head and neck squamous cell carcinoma

OBJECTIVE

There is currently no consensus on the ideal protocol of imaging for post-treatment surveillance of head and neck squamous cell carcinoma. This study aimed to consolidate existing evidence on the diagnostic effectiveness of positron emission tomography-computed tomography versus magnetic resonance imaging.

METHOD

Systematic electronic searches were conducted using Medline, Embase and Cochrane Library (updated February 2021) to identify studies directly comparing positron emission tomography-computed tomography and magnetic resonance imaging scans for detecting locoregional recurrence or residual disease for post-treatment surveillance.

RESULTS

Searches identified 3164 unique records, with three studies included for meta-analysis, comprising 176 patients. The weighted pooled estimates of sensitivity and specificity for scans performed three to six months post-curative treatment were: positron emission tomography-computed tomography, 0.68 (95 per cent confidence interval, 0.49-0.84) and 0.89 (95 per cent confidence interval, 0.84-0.93); magnetic resonance imaging, 0.72 (95 per cent confidence interval, 0.54-0.88) and 0.85 (95 per cent confidence interval, 0.79-0.89), respectively.

CONCLUSION

Existing studies do not provide evidence for superiority of either positron emission tomography-computed tomography or magnetic resonance imaging in detecting locoregional recurrence or residual disease following curative treatment of head and neck squamous cell carcinoma.

Pulmonary Screening Practices of Otolaryngology-Head and Neck Surgeons Across Saudi Arabia in the Posttreatment Surveillance of Squamous Cell Carcinoma: Cross-sectional Survey Study

Background

With respect to patients with head and neck squamous cell carcinoma (HNSCC), posttreatment surveillance for distant disease has mostly focused on the lungs, as HNSCC distant metastasis occurs in this organ in 90% of HNSCC cases. Additionally, the incidence rate of primary tumors in the lungs is high due to the field cancerization of the entire upper aerodigestive tract.

Objective

Our cross-sectional survey study aims to evaluate the current beliefs and pulmonary screening practices of otolaryngology–head and neck surgeons across Saudi Arabia with respect to the posttreatment surveillance of HNSCC.

Methods

This nationwide cross-sectional survey was conducted among head and neck surgeon members of the Saudi Society of Otolaryngology from June 1 to June 30, 2020. A predesigned questionnaire was used for data collection, and a descriptive analysis was carried out.

Results

This study included 22 participants and had a 78% (22/28) response rate. This study found that the majority of participants (9/22, 41%) used lung radiography for routine lung screening during posttreatment follow-ups, whereas 32% (7/22) used low-dose computed tomography (CT; 7/22, 32%). With regard to the number of years for which participants perform lung screening during follow-ups, the majority of participants (17/22, 77%) reported 5 years, and only 9% (2/22) have performed lifelong lung screening. With regard to the frequency of lung screening, 77% (17/22) of participants conduct screening annually, 18% (4/22) conduct screening half-yearly, and 5% (1/22) conduct screening biennially. With regard to beliefs about the effectiveness of screening procedures in reducing lung cancer mortality rates during follow-ups, 36% (8/22) of participants believed them to be very effective or somewhat effective, 18% (4/22) did not know, and only 9% (2/22) believed that they were not effective.

Conclusions

The participants mainly used lung radiography (9/22, 41%), low-dose CT (7/22, 32%), or positron emission tomography/CT (6/22, 27%) as a routine lung screening method during the posttreatment follow-up of patients with head and neck cancer for 5 years (17/22, 77%) or 10 years (3/22, 14%), and only a small percentage of participants have performed lifelong lung screening (2/22, 9%). Lung screening was mostly conducted annually or half-yearly. Such screening was believed to be very effective or somewhat effective.

Diagnostic performance of core needle biopsy for nodal recurrences in patients with head and neck squamous cell carcinoma

This study investigated the diagnostic accuracy and affecting factors of ultrasound (US)-guided core-needle biopsy (CNB) in patients with treated head and neck squamous cell carcinoma (HNSCC). We retrospectively reviewed patients with treated HNSCC who received US-guided CNB from January 2011 to December 2018 with corresponding imaging. Pathological necrosis and fibrosis of targeted lymph nodes (LNs) were evaluated. We analyzed the correlation between CNB accuracy and clinical and pathological characteristics. In total, 260 patients were included. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of CNB for nodal recurrence were 84.47%, 100%, 100%, 54.67%, and 86.92%, respectively. CNB of fibrotic LNs had significantly worse sensitivity, NPV, and accuracy than that of non-fibrotic LNs. Similarly, CNB of necrotic LNs had significantly worse sensitivity, NPV, and accuracy than non-necrotic LNs. Multivariate regression revealed that fibrotic LN was the only independent factor for a true positive rate, whereas both necrotic LN and fibrotic LN were independent factors for a false negative rate. The diagnostic accuracy of CNB in treated HNSCC patients is affected by LN necrosis and fibrosis. Therefore, CNB results, particularly for necrotic or fibrotic LNs, should be interpreted carefully.

Longitudinal detection of somatic mutations in saliva and plasma for the surveillance of oral squamous cell carcinomas

Purposes

Although clinical and radiological examinations can be used to diagnose oral cancer, and surgical pathology remains the gold standard, these conventional methods have limitations. We evaluated the feasibility of longitudinal next-generation sequencing-based liquid biopsy for oral squamous cell carcinoma surveillance.

Materials and methods

Eleven patients were enrolled, and plasma and saliva were collected before, and 1, 3, and 6 months after surgery. Tumor-specific mutations were selected using paired, whole-exome analyses of tumor tissues and whole blood. Genes frequently mutated in head and neck cancer were identified using the Cancer Genome Atlas (TCGA) and Catalogue of Somatic Mutations in Cancer (COSMIC) databases to design targeted deep sequencing panels.

Results

In five of the six patients with recurrent cancer, circulating tumor DNA (ctDNA) was detected earlier with liquid biopsy than with conventional monitoring techniques. Moreover, patients without recurrence exhibited decreased ctDNA allele frequency post-treatment.

Conclusions

Longitudinal liquid biopsy of plasma and saliva may be feasible for detecting somatic mutations associated with oral squamous cell carcinomas. It might be attributable to determine early tumor recurrence through genetic analysis of ctDNA.

Digital Workflow in Maxillofacial Prosthodontics—An Update on Defect Data Acquisition, Editing and Design Using Open-Source and Commercial Available Software

Background: A maxillofacial prosthesis, an alternative to surgery for the rehabilitation of patients with facial disabilities (congenital or acquired due to malignant disease or trauma), are meant to replace parts of the face or missing areas of bone and soft tissue and restore oral functions such as swallowing, speech and chewing, with the main goal being to improve the quality of life of the patients. The conventional procedures for maxillofacial prosthesis manufacturing involve several complex steps, are very traumatic for the patient and rely on the skills of the maxillofacial team. Computer-aided design and computer-aided manufacturing have opened a new approach to the fabrication of maxillofacial prostheses. Our review aimed to perform an update on the digital design of a maxillofacial prosthesis, emphasizing the available methods of data acquisition for the extraoral, intraoral and complex defects in the maxillofacial region and assessing the software used for data processing and part design. Methods: A search in the PubMed and Scopus databases was done using the predefined MeSH terms. Results: Partially and complete digital workflows were successfully applied for extraoral and intraoral prosthesis manufacturing. Conclusions: To date, the software and interface used to process and design maxillofacial prostheses are expensive, not typical for this purpose and accessible only to very skilled dental professionals or to computer-aided design (CAD) engineers. As the demand for a digital approach to maxillofacial rehabilitation increases, more support from the software designer or manufacturer will be necessary to create user-friendly and accessible modules similar to those used in dental laboratories.

Comparative effectiveness of posttreatment imaging modalities for Medicare patients with advanced head and neck cancer

BACKGROUND

Persistent controversy exists with regard to how and when patients with head and neck cancer should undergo imaging after definitive therapy. The current study was conducted to evaluate whether the type of imaging modality used in posttreatment imaging impacts cancer-specific survival for patients with advanced head and neck squamous cell carcinoma.

METHODS

A retrospective study of National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) program-Medicare-linked data in patients with an advanced stage of the 3 most common head and neck malignancies (oral cavity, oropharynx, and larynx) was conducted. Hazard ratios and 95% CIs for cancer-specific survival were estimated for patients diagnosed with any of these cancers between 2006 and 2015.

RESULTS

Significant improvement with regard to cancer-specific survival was observed among patients with American Joint Committee on Cancer stage III and stage IVA laryngeal cancer who underwent positron emission tomography (PET) and/or computed tomography (CT) imaging during the first 6 months after receipt of definitive treatment (hazard ratio, 0.517; 95% CI, 0.33-0.811) compared with those who underwent CT. There was a trend toward an improvement in cancer-specific survival among patients with oral cavity or oropharyngeal malignancies who underwent PET/CT imaging, but it did not reach statistical significance.

CONCLUSIONS

Compared with CT imaging, posttreatment imaging with PET was associated with improved survival in patients with advanced laryngeal carcinoma.

Imaging of the post-treatment neck

Post-treatment imaging of the neck is complex. It is important to have an understanding of the expected treatment related appearances as well as the possible complications. Common findings after radiation therapy include generalised soft-tissue oedema and thickening of the skin and platysma muscle. There are a number of complications of radiation that may be seen on imaging, including osteoradionecrosis, chondronecrosis, and accelerated atherosclerosis. Surgical procedures are variable depending on the primary tumour site and extent. The use of flap reconstructions can further complicate the imaging appearances. Any new nodule of enhancement or bone/cartilage erosion should raise concern for tumour recurrence. It is also important to assess for nodal recurrence. A standardised approach to reporting may help to increase accuracy and guide treatment decisions.

Surveillance imaging for patients with head and neck cancer treated with definitive radiotherapy: A partially observed Markov decision process model

BACKGROUND

A possible surveillance model for patients with head and neck cancer (HNC) who received definitive radiotherapy was created using a partially observed Markov decision process. The goal of this model is to guide surveillance imaging policies after definitive radiotherapy.

METHODS

The partially observed Markov decision process model was formulated to determine the optimal times to scan patients. Transition probabilities were computed using a data set of 1508 patients with HNC who received definitive radiotherapy between the years 2000 and 2010. Kernel density estimation was used to smooth the sample distributions. The reward function was derived using cost estimates from the literature. Additional model parameters were estimated using either data from the literature or clinical expertise.

RESULTS

When considering all forms of relapse, the model showed that the optimal time between scans was longer than the time intervals used in the institutional guidelines. The optimal policy dictates that there should be less time between surveillance scans immediately after treatment compared with years after treatment. Comparable results also held when only locoregional relapses were considered as relapse events in the model. Simulation results for the inclusive relapse cases showed that <15% of patients experienced a relapse over a simulated 36-month surveillance program.

CONCLUSIONS

This model suggests that less frequent surveillance scan policies can maintain adequate information on relapse status for patients with HNC treated with radiotherapy. This model could potentially translate into a more cost-effective surveillance program for this group of patients.