Surveillance radiologic imaging after treatment of oropharyngeal cancer: a review

Factors associated with detection of oligometastatic recurrence and outcome following definitive (Chemo)radiotherapy for oropharyngeal carcinoma

PURPOSE/BACKGROUND

We aim to describe characteristics and patterns of detection of distant metastasis (DM) and subsequent outcomes following definitive (chemo)radiotherapy [(C)RT] for oropharyngeal cancer (OPC).

MATERIAL/METHODS

OPC patients who developed DM after initial complete response to (C)RT from 2010 to 2020 were included. DM were classified as oligometastases (≤5 lesions) vs polymetastases. Interval from prior normal surveillance imaging to DM detection was recorded. Multivariable analysis (MVA) was performed for overall survival (OS) after DM.

RESULTS

A total of 124 patients were eligible. Most (116/124, 94 %) developed DMs within the thorax, of whom 72 (58 %) had thorax only DM. Oligometastases (n = 46) vs polymetastases (n = 78) were more commonly detected without DM-related symptoms (76 % vs 55 %, p = 0.003) and identified with shorter interval from previous normal imaging (median 7.9 vs 12.7 months, p = 0.030). Median follow-up from DM diagnosis was 31.5 months. Three-year OS after DM was higher for patients with oligometastases vs polymetastases (32 % vs 5 %, p < 0.001). Patients with oligometastases who received salvage therapy had a longer 3-year OS (vs not) (63 % vs 7 %, p < 0.001). On MVA, salvage therapy (Hazard Ratio [HR) 0.32, p = 0.005), HPV + status (HR 0.50, p = 0.002) and thorax only distant metastases (HR 0.64, p = 0.034) were associated with longer OS.

CONCLUSIONS

Nearly one-third of first DM in OPC following initial complete response to (C)RT are oligometastases and most occur within the thorax. Most oligometastases are asymptomatic and more commonly detected following a shorter surveillance scan interval. DM-targeted salvage therapy for oligometastases is associated with longer OS. Prospective studies refining surveillance algorithms to increase detection of oligometastases in asymptomatic high-risk OPC patients are indicated.

Risk and Clinical Risk Factors Associated With Late Lower Cranial Neuropathy in Long-term Oropharyngeal Squamous Cell Carcinoma Survivors

Importance

Lower cranial neuropathy (LCNP) is a rare, but permanent, late effect of radiotherapy and other cancer therapies. Lower cranial neuropathy is associated with excess cancer-related symptoms and worse swallowing-related quality of life. Few studies have investigated risk and clinical factors associated with late LCNP among patients with long-term survival of oropharyngeal squamous cell carcinoma (OPSCC survivors).

Objective

To estimate the cumulative incidence of and identify clinical factors associated with late LCNP among long-term OPSCC survivors.

Design, Setting, and Participants

This single-institution cohort study included disease-free adult OPSCC survivors who completed curative treatment from January 1, 2000, to December 31, 2013. Exclusion criteria consisted of baseline LCNP, recurrent head and neck cancer, treatment at other institutions, death, and a second primary, persistent, or recurrent malignant neoplasm of the head and neck less than 3 months after treatment. Median survival of OPSCC among the 2021 eligible patients was 6.8 (range, 0.3-18.4) years. Data were analyzed from October 12, 2019, to November 13, 2020.

Main Outcomes and Measures

Late LCNP events were defined by neuropathy of the glossopharyngeal, vagus, and/or hypoglossal cranial nerves at least 3 months after cancer therapy. Cumulative incidence of LCNP was estimated using the Kaplan-Meier method, and multivariable Cox proportional hazards models were fit.

Results

Among the 2021 OPSCC survivors included in the analysis of this cohort study (1740 [86.1%] male; median age, 56 [range, 28-86] years), 88 (4.4%) were diagnosed with late LCNP, with median time to LCNP of 5.4 (range, 0.3-14.1) years after treatment. Cumulative incidence of LCNP was 0.024 (95% CI, 0.017-0.032) at 5 years, 0.061 (95% CI, 0.048-0.078) at 10 years, and 0.098 (95% CI, 0.075-0.128) at 15 years of follow-up. Multivariable Cox proportional hazards regression identified T4 vs T1 classification (hazard ratio [HR], 3.82; 95% CI, 1.85-7.86) and accelerated vs standard radiotherapy fractionation (HR, 2.15; 95% CI, 1.34-3.45) as independently associated with late LCNP status, after adjustment. Among the subgroup of 1986 patients with nonsurgical treatment, induction chemotherapy regimens including combined docetaxel, cisplatin, and fluorouracil (TPF) (HR, 2.51; 95% CI, 1.35-4.67) and TPF with cetuximab (HR, 5.80; 95% CI, 1.74-19.35) along with T classification and accelerated radiotherapy fractionation were associated with late LCNP status after adjustment.

Conclusions and Relevance

This single-institution cohort study found that, although rare in the population overall, cumulative risk of late LCNP progressed to 10% during the survivors' lifetime. As expected, clinical factors associated with LCNP primarily reflected greater tumor burden and treatment intensity. Further efforts are necessary to investigate risk-reduction strategies as well as surveillance and management strategies for this disabling late effect of cancer treatment.

Head and neck imaging surveillance strategy for HPV-positive oropharyngeal carcinoma following definitive (chemo)radiotherapy

PURPOSE

To describe the utilization pattern of head and neck (HN) surveillance imaging and explore the optimal strategy for radiologic "residual" lymph node (LN) surveillance following definitive (chemo)radiotherapy (RT/CRT) in human papillomavirus (HPV)+ oropharyngeal carcinoma (OPC).

METHODS

All HPV+ OPC patients who completed RT/CRT from 2012 to 2015 were included. Schedule and rationale for post-treatment HN-CT/MRI were recorded. Imaging findings and oncologic outcomes were evaluated.

RESULTS

A total of 1036 scans in 412 patients were reviewed: 414 scans for first post-treatment response assessment and 622 scans for the following reasons: follow-up of radiologic "residual" LN(s) (293 scans/175 patients); local symptoms (227/146); other (17/16); unknown (85/66). Rate of scans with "unstated" reason varied significantly among clinicians (3-28%, p < 0.001) and none of them yielded any positive imaging findings. First post-treatment scans identified 192 (47%) patients with radiologic "residual" LNs. Neck dissection (ND) was performed in 28 patients: 16 immediately (6/16 positive), 10 after one follow-up scan (2/10 positive), and 2 after 2nd follow-up scan (1/2 positive). Thirty patients had >2 consecutive follow-up scans at 2-3-month intervals, and none showed subsequent imaging progression or regional failure.

CONCLUSIONS

Pattern of HN imaging utilization for surveillance varied significantly among clinicians. Imaging surveillance reduces the need for ND. However, routine HN-CT/MR surveillance without clinical symptoms/signs does not demonstrate proven value in identifying locoregional failure or toxicity. Radiologic "residual" LNs without adverse features are common. If two subsequent follow-up scans demonstrate stable/regressing radiologic "residual" LNs, clinical surveillance without further imaging appears to be safe in this population.

Association of Fludeoxyglucose F 18-Labeled Positron Emission Tomography and Computed Tomography With the Detection of Oropharyngeal Cancer Recurrence

Importance

No guidelines at present describe when fludeoxyglucose F 18-labeled positron emission tomography and computed tomography (FDG PET-CT) should be used in the initial posttreatment period for evaluation of oropharyngeal squamous cell carcinoma treatment outcome and recurrence.

Objective

To compare accuracies of the initial posttreatment PET-CT between primary treatment groups and to define indicators of false-positive findings.

Design, Setting, and Participants

This retrospective cohort study identified adults with a new diagnosis of oropharyngeal squamous cell carcinoma who received treatment with curative intent from October 1, 2006, through November 30, 2016, using the Alberta Cancer Registry (n = 380). Patients who underwent PET-CT within 1 year of treatment completion were included (n = 190). Of these, 103 patients (54.2%) had PET-CT findings positive for residual or recurrent disease, and 61 (32.1%) had false-positive findings. Among the 61 patients, 42 (68.9%) had received chemoradiotherapy (CRT) and 19 (31.1%) had primary surgery. Forty-two patients had true-positive findings, indicating a prevalence rate of disease of 22.1%. Data were analyzed from July through October 2017.

Exposures

One of 2 primary treatment modalities (surgery with or without adjuvant therapy vs CRT). All patients had posttreatment FDG PET-CT.

Main Outcomes and Measures

Primary outcome measures included the diagnostic odds ratio, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of PET-CT for detecting residual and/or recurrent disease. A multivariate analysis determined indicators of false-positive findings. Discriminative ability was assessed using receiver operating characteristic curve analysis of maximum standardized uptake value (SUVmax) metabolic data.

Results

Of the 190 participants, 77.9% were men, with a mean (SD) age at diagnosis of 58.5 (8.5) years. The diagnostic odds ratio was 19.3 (95% CI, 5.7-65.1); pooled sensitivity, 93.3% (95% CI, 80.7%-98.3%); and pooled specificity, 57.9% (95% CI, 49.4%-66.0%). The PPV of detecting disease was 54.7% (95% CI, 38.8%-69.8%) for primary surgery and 31.1% (95% CI, 20.2%-44.4%) for CRT. The NPV was 100% (95% CI, 94.7%-100%) for primary surgery and 96.6% (95% CI, 89.5%-99.1%) for CRT. Multivariate analysis identified treatment type, p16 disease, and smoking status as indicative of false-positive findings. In the receiver operating characteristic curve analysis for primary tumors, the optimal cutoff SUVmax for indicating true- vs false-positive results was 5.1 for surgically treated patients (area under the curve, 0.729; 95% CI, 0.570-0.888) and 5.3 for patients treated with CRT (area under the curve, 0.844; 95% CI, 0.700-0.989).

Conclusions and Relevance

The results indicate a higher specificity for FDG PET-CT for initial posttreatment surveillance imaging among patients treated with primary surgery compared with nonsurgical management. Both sets of patients with posttreatment FDG PET-CT findings with an SUVmax greater than 5.0 should undergo close evaluation for possible residual or recurrent disease.

EUS of the neck: A comprehensive anatomical reference for the staging of head and neck cancer (with videos)

The use of EUS has application in the nodal staging of head and neck cancer. The technique and the anatomy of head and neck region using EUS have not been described. EUS from three stations in thoracic esophagus, cervical esophagus, and hypopharynx can allow imaging of head and neck. In this article we describe the normal structures from the three stations. The EUS imaging of head and neck can give relevant and additional information in malignancies of head and neck.

De-escalation of post-treatment surveillance in oropharyngeal cancer

BACKGROUND

The majority of new oropharyngeal squamous cell carcinoma (OPSCC) cases are associated with human papillomavirus and favorable prognosis. Post-treatment follow-up should be targeted to patients at greatest risk for disease recurrence.

METHODS

To assess the benefits of routine clinical surveillance in OPSCC, we reviewed all follow-up visits conducted in 2014 at Helsinki University Hospital Department of Otorhinolaryngology.

RESULTS

Of 366 visits, 26 (7%) were from patients presenting with a new symptom, and disease recurrence was detected in four. The presence of a new symptom was significantly associated with disease recurrence (P < 0.001). Of 366 visits, 340 (93%) were from patients presenting without new symptoms, and not a single recurrence was found during these visits.

CONCLUSIONS

Based on our findings, and previous studies assessing the prognosis and pattern of recurrent OPSCC, we concluded that the number of routine post-treatment visits can be reduced. Follow-up should rather focus on symptom-directed examinations.

Posttreatment surveillance PET/CT for HPV-associated oropharyngeal cancer

BACKGROUND

Surveillance positron emission tomography-computed tomography (PET/CT) is commonly used for treatment assessment of radiation therapy in head and neck cancer. However, human papillomavirus-associated oropharyngeal squamous cell carcinoma (HPV+OPSCC) patients represent a unique subpopulation, for which the utility of surveillance PET/CT has not been well studied.

METHODS

In this retrospective chart review comprising 233 HPV+OPSCC patients, we evaluated surveillance PET/CT for diagnostic accuracy, downstream clinical impact, and survival.

RESULTS

Surveillance PET/CT demonstrated 100% negative predictive value and sensitivity, 59.9% specificity, and 13.4% positive predictive value. Surveillance PET/CT led to 90 imaging studies and 31 biopsies; 91.1% and 77.4% were negative for recurrence, respectively. Surveillance PET/CT led to meaningful salvage therapy in 1.6% of cases. PET/CT-detected recurrences did not have improved survival compared to clinically detected recurrences.

CONCLUSION

For HPV+OPSCC patients, surveillance PET/CTs frequently lead to unnecessary testing and rarely to meaningful disease salvage. They have no demonstrated survival benefit and should be interpreted cautiously to prevent patient harm.

Trends in Risks for Second Primary Cancers Associated With Index Human Papillomavirus-Associated Cancers

IMPORTANCE

In the last 4 decades, survival among patients with human papillomavirus (HPV)-associated cancers has improved, while the incidence of these cancers has increased among younger cohorts. Among survivors of HPV-associated cancers, persistent HPV infection may remain a risk factor for preventable HPV-associated second primary cancers (HPV-SPCs).

OBJECTIVES

To investigate the risk of HPV-SPCs among survivors of HPV-associated index cancers and to test the hypothesis that the HPV-SPC risk among these persons has increased over the last 4 decades.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study of 9 cancer registries of the Surveillance, Epidemiology, and End Results (SEER) database was conducted to identify patients with HPV-associated (cervical, vaginal, vulvar, oropharyngeal, anal, and penile) cancers diagnosed from January 1, 1973, through December 31, 2014. The dates of analysis were July 1, 2017, to January 31, 2018.

MAIN OUTCOMES AND MEASURES

The HPV-SPC risk was quantified by calculating standard incidence ratios (SIRs) and excess absolute risks (EARs) per 10 000 person-years at risk (PYR). The HPV-SPC risk by time was estimated using Poisson regression.

RESULTS

From 113 272 (73 085 female and 40 187 male) survivors of HPV-associated cancers, 1397 women and 1098 men developed HPV-SPCs. The SIRs for HPV-SPCs were 6.2 (95% CI, 5.9-6.6) among women and 15.8 (95% CI, 14.9-16.8) among men. The EARs were 18.2 per 10 000 PYR for women and 53.5 per 10 000 PYR for men. Among both women and men, those who had index oropharyngeal cancers had the highest HPV-SPC risk (SIR, 19.8 [95% CI, 18.4-21.4] and EAR, 80.6 per 10 000 PYR among women; SIR, 18.0 [95% CI, 16.9-19.1] and EAR, 61.5 per 10 000 PYR among men). Women who had index cervical cancers and men who had index anal cancers had the lowest HPV-SPC risk (SIR, 2.4 [95% CI, 2.2-2.7] and EAR, 4.5 per 10 000 PYR among women; SIR, 6.5 [95% CI, 4.7-8.8] and EAR, 18.5 per 10 000 PYR among men). Both women and men who had index HPV-associated cancers of any kind had a significantly higher risk of oropharyngeal HPV-SPCs. Over the last 4 decades, the risk of developing most types of HPV-SPCs after index cervical, vaginal, and vulvar cancers increased.

CONCLUSIONS AND RELEVANCE

According to this study, the HPV-SPC risk among survivors of HPV-associated cancers is significant, implying that persistent HPV infection at multiple sites may be associated with HPV-SPCs. These findings have the potential to inform surveillance recommendations for survivors of HPV-associated cancers.

The interobserver agreement in the detection of recurrent HNSCC using MRI including diffusion weighted MRI

INTRODUCTION

For the detection of local recurrences of head and neck squamous cell carcinomas (HNSCC) after (chemo)radiation, diagnostic imaging is generally performed. Diffusion weighted magnetic resonance imaging (DW-MRI) has been proven to be able to adequately diagnose the presence of cancer. However evaluation of DW-MR images for recurrences is difficult and could be subject to individual interpretation.

AIM

To determine the interobserver agreement, intraobserver agreement and influence of experience of radiologists in the assessment of DW-MRI in patients clinically suspected of local recurrent HNSCC after (chemo)radiation.

METHODS

Ten experienced head and neck radiologists assessed follow-up MRI including DW-MRI series of 10 patients for the existence of local recurrence on a two point decision scale (local recurrence or local control). Patients were clinically suspected for a recurrence of laryngeal (n = 3), hypopharyngeal (n = 3) or oropharyngeal (n = 4) cancer after (chemo)radiation with curative intent. Fleiss' and Cohen's Kappa were used to determine interobserver agreement and intraobserver agreement, respectively.

RESULTS

Interobserver agreement was κ = 0.55. Intraobserver agreement was κ = 0.80. Prior experience within the field of radiology and with DW-MRI had no significant influence on the scoring.

CONCLUSION

For the assessment of HNSCC recurrence after (chemo)radiation by DW-MRI, moderate interobserver agreement and substantial intraobserver agreement was found.

AHNS Series: Do you know your guidelines? Evidence-based management of oral cavity cancers

Oral cavity squamous cell carcinoma (OCSCC) is the most common nonmelanoma head and neck cancer in the world, with an estimated 405 000 new cases expected each year. Subsites of the oral cavity include the alveolar ridge, buccal mucosa, anterior tongue, tonsillar pillar, retromolar trigone, hard palate, gingiva, and floor of the mouth. In this issue of the AHNS "Do you know your guidelines?" series, we review the evidence-based approach to the management of oral cavity carcinomas based on the framework provided by the National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology.

Positron emission tomography/computed tomography after primary transoral robotic surgery for oropharyngeal squamous cell carcinoma

OBJECTIVES/HYPOTHESIS

To assess the first post-treatment positron emission tomography/computed tomography (PET/CT) in prediction of disease-free survival after primary transoral robotic surgery (TORS) for oropharyngeal squamous cell carcinoma (OPSCC) with or without adjuvant chemoradiation.

STUDY DESIGN

Retrospective review.

METHODS

Ninety-five patients with OPSCC treated with primary TORS from 2010 to 2014 at a single tertiary academic center were evaluated with PET/CT. Imaging was performed between 2 and 7 months after completing all treatment. Radiology findings were categorized as 1) negative, noting either complete resolution of foci without evidence of disease or anatomical changes likely attributed to treatment; 2) equivocal, noting equal likelihood of malignancy versus treatment-related changes; or 3) positive, noting either findings concerning for malignancy or new hyperactivity not attributed to treatment-related changes. The median follow-up time was 31 months (range, 23-63 months). Recurrence was defined as biopsy-proven invasive malignancy or clinical suspicion sufficient to initiate treatment occurring within 3 years of the completion of all treatment.

RESULTS

Of 95 total patients with at least 2 years of follow-up records, 26 had positive post-treatment PET/CT results, with five experiencing actual recurrences. Of 69 patients with negative post-treatment PET/CT results, none experienced recurrences. These results indicate a sensitivity of 100%, specificity of 77%, positive predictive value of 19%, and negative predictive value of 100%.

CONCLUSIONS

A majority of TORS patients (73%) will have a negative first post-treatment PET/CT. A single negative post-treatment PET/CT is strongly correlated with 2-year disease-free survival in patients treated with primary TORS and may warrant decreased surveillance imaging.

LEVEL OF EVIDENCE

4 Laryngoscope, 127:2050-2056, 2017.

Follow-up in Head and Neck Cancer: Do More Does It Mean Do Better? A Systematic Review and Our Proposal Based on Our Experience

As the patients population ages, cancer screening increases, and cancer treatments improve, millions more head and neck carcinoma (HNC) patients will be classified as cancer survivors in the future. Change in epidemiology with human papillomavirus related HNC leads to a number of young treated patients. After treatment for HNC intensive surveillance, including ear, nose and throat (ENT) endoscopy, imaging, and serology, confers a survival benefit that became less evident in unresectable recurrence. We performed a comprehensive revision of literature and analyzed the experience of our centre. We revised publications on this topic and added data derived from the interdisciplinary work of experts within medical oncology, ENT, and radiation oncology scientific societies. We retrospectively collected local and distant recurrence of chemoradiation treated patients at Santa Croce and Carle University Hospital. A HNC follow-up program is not already codified and worldwide accepted. There is a need of scheduled follow-up. We suggest adopting a standardized follow-up guideline, although a multidisciplinary approach is frequently requested to tailor surveillance program and treatment on each patient.

Imaging of spaces of neck and mediastinum by endoscopic ultrasound

Endoscopic ultrasound (EUS) of the mediastinum was pioneered by gastroenterologists, and it was taken up by pulmonologists when the smaller-diameter endobronchial ultrasound (EBUS) scope was designed after a few years. The pulmonologists’ approach remained largely confined to entry from the trachea, but they soon realized that the esophagus was an alternative route of entry by the EBUS scope. The new generations of interventionists are facing the challenge of learning two techniques (EUS and EBUS) from two routes (esophagus and trachea). The International Association for the Study of Lung Cancer (IASLC) proposed a classification of mediastinal lymph nodes at different stations that lie within the boundaries of specific spaces. These interventionists need clear definitions of landmarks and clear techniques to identify the spaces. There are enough descriptions of spaces of the neck and the mediastinum in the literature, yet the topic mentioned above has never been discussed separately. The anatomical structures, landmarks, and boundaries of spaces will be important to interventionists in the near future during performances of endosonography. This article combines the baseline anatomy of the spaces with the actual imaging during EUS.