Oligometastatic status as predictor of survival in metastatic human papillomavirus-positive oropharyngeal carcinoma

Oligometastatic Head and Neck Cancer: Challenges and Perspectives

Simple Summary

Oligometastasis represents a disease state and an opportunity for cure when metastases emerge. Emerging evidence supports that most head and neck cancer patients with oligometastatic disease are likely to benefit from curative intent local ablative therapy if appropriate selection criteria are applied. Biomarkers to predict development of oligometastasis, as well as to identify which patients could benefit from a radical intent approach, are under investigation. This review summarizes recent knowledge about the characteristics, investigational efforts, and evidence for local ablation regarding oligometastasis in head and neck cancer. We also describe the challenges and opportunities in patient selection and discuss the role of radiotherapy and immunotherapy combinations to enhance anti-tumor immunity.

Abstract

A minority of patients with metastatic head and neck squamous cell carcinoma (HNSCC) present with oligometastatic disease. Oligometastasis not only reflects a disease state, but might also present an opportunity for cure in the metastatic setting. Radical ablation of all oligometastatic sites may confer prolonged survival and possibly achieve cure in some patients. However, substantial debate remains about whether patients with oligometastatic disease could benefit from curative intent therapy or whether aggressive treatments expose some patients to futile toxicity. Optimal selection of patients, carefully balancing the currently known prognostic factors against the risks of toxicity is critical. Emerging evidence suggests that patients with a limited burden of disease, viral-related pharyngeal cancer, metachronous metastasis and lung-only metastasis may benefit most from this approach. Efforts are underway to identify biomarkers that can detect oligometastasis and better select patients who would derive the maximum benefit from an aggressive radical approach. The combination of radiotherapy and immunotherapy promises to enhance the anti-tumoral immune response and help overcome resistance. However, optimization of management algorithms, including patient selection, radiation dose and sequencing, will be critical in upcoming clinical trials. This review summarizes recent knowledge about the characteristics and investigational efforts regarding oligometastasis in HNSCC.

Assessing plasma circulating tumor human papillomavirus (HPV) DNA in determining treatment response in HPV-associated oropharyngeal cancer

BACKGROUND

Human papillomavirus (HPV)-mediated oropharyngeal squamous cell carcinoma is a subset of head and neck cancer with a unique mechanism of carcinogenesis. Local disease is treated definitively with a multimodal approach. Navigating recurrences can be challenging, as they are sometimes indiscernible from de novo primary malignancies. Identification of dynamic biomarkers that are specific to HPV-mediated disease may assist in disease monitoring. We present a 78-year-old man who developed a squamous cell carcinoma in the lung 7 years after completing definitive chemoradiation for his p16+ head and neck squamous cell carcinoma.

METHODS

A novel assay for plasma circulating tumor HPV DNA was employed and provided a tool for longitudinal disease monitoring during therapy.

CONCLUSION

We bring attention to a novel assay and highlight its potential for use in the treatment paradigm of HPV-mediated oropharyngeal carcinoma.

Prognostic factors for bone metastases from head and neck squamous cell carcinoma: A case series of 97 patients

Although bone is the second-most frequent site of distant metastases of head and neck squamous cell carcinoma (HNSCC), variable prognostic factors in patients with bone metastases from HNSCC have not been fully investigated. The aim of the present study was to assess the prognostic factors affecting overall survival (OS) in these patients. The medical records of 97 patients at two institutions who developed bone metastases from HNSCC between January 2010 and December 2020 were retrospectively reviewed. A multivariate analysis using a Cox proportional hazards model was performed to identify potential clinical predictive factors for longer OS. The median OS was 7 months, and the 1- and 2-year OS rates for all patients were 35.4 and 19.2%, respectively. The independent predictive factors for longer OS were single bone metastasis, good performance status and administration of systemic chemotherapy. The median OS with each predictor was 10, 10 and 10.5 months, respectively. In a selected group of patients with these three factors, the OS was 14.5 months. In conclusion, single bone metastasis, a good performance status and systemic chemotherapy were independent predictors of longer OS in patients with HNSCC, but their contributions were limited.

Distinct Outcomes of Oropharyngeal Squamous Cell Carcinoma Patients after Distant Failure According to p16 Status: Implication in Therapeutic Options

Introduction: Recent modifications in the epidemiology of oropharyngeal squamous cell carcinoma (OSCC) have led to the increase of Human papillomavirus (HPV) related metastatic head and neck cancer patients with high life expectancy even at advanced stage, low comorbidity and still restricted systemic therapy opportunities. In the recent era of ablative therapies’ development, oligometastatic HPV OSCC patients are indubitably good candidates for intensified treatment. However, data related to outcomes after optimised management of metastatic sites are dramatically missing. Materials and patients: In our cohort of 186 unselected consecutive OSCC patients treated with curative intent at our institution between 2009 and 2013, we analysed the incidence, treatment and outcomes of distant metastatic (DM) failure according to p16 status. Results: After a median follow-up of 4.2 years (95% CI: 3.8–4.4) from primary diagnosis of OSCC, 21/95 p16− patients (22.1%) vs. 8/91 (8.8%) p16+ patients presented DM failure with a median interval of 11 (range 0–46) and 28 months (range 0–71), respectively (p = 0.10). Overall survival (OS) after DM failure was significantly higher in p16+ patients with a two-year OS rate of 75% and 15% for p16+ and p16−, respectively (p = 0.002). In eight HPV-related metastatic patients, three underwent ablative lung metastasis treatment and are still complete responders four to five years later. Conclusion: This study highlights distinct outcomes of metastatic HPV-related OSCC patients emphasised by three long-term complete responders after lung ablative treatment. In patients with high life expectancy and limited tumour burden, the question of ablative treatment such as metastasectomy or stereotactic ablative radiotherapy (SBRT) should be addressed.

Oligometastases in head and neck carcinoma and their impact on management

Historically, patients with head and neck squamous cell carcinoma (HNSCC) with distant metastases were regarded as palliative. Oligometastasis (OM) refers to patients with a limited number of distant metastatic deposits. Treatment of patients with OMs has been reported in patients with lung, colon, breast, prostate and brain malignancies. Selected patients with oligometastatic HNSCC have a higher probability of durable disease control and cure and these patients should be treated aggressively. Treatment options for patients with HNSCC OMs include single or combinations of the three arms of cancer treatment, that is surgery, radiotherapy and chemotherapy/immunotherapy. To date, there are limited studies reporting the management of OM with head and neck malignancy. This review will give insights into the management of OMs in HNSCC.

Prognostic Impact of Metastatic Site and Pattern in Patients with Metastatic Head and Neck Cancer

OBJECTIVES/HYPOTHESIS

Investigate the relationship between site and pattern of distant metastasis (DM) and overall survival (OS) in a multi-institutional cohort of patients with DM head and neck cancer (HNC).

STUDY DESIGN

Retrospective review.

METHODS

283 patients treated at 4 academic centers in the Midwest HNC Consortium between 2000 and 2015 were retrospectively reviewed. Disease patterns were divided between solitary metastatic versus polymetastatic (≥2 sites) disease. Survival functions for clinically relevant variables were estimated using Kaplan-Meier and Cox proportional hazards models.

RESULTS

Median OS for all patients was 9.0 months (95% confidence interval [CI]: 7.4-10.6). Lung (n = 220, 77.7%) was the most common site of DM, followed by bone (n = 90, 31.8%), mediastinal lymph nodes (n = 55, 19.4%), liver (n = 41, 14.5%), and brain (n = 17, 6.0%). Bone metastases were independently associated with the worst prognosis (hazard ratio [HR] = 1.6, 95% CI: 1.3-2.1). On univariate analysis, brain metastases were associated with improved prognosis (HR = 0.5, 95% CI: 0.3-0.9), although this was not statistically significant on the multivariate analysis. Polymetastatic disease was present in the majority of patients (n = 230, 81.3%) and was associated with a worse prognosis compared to solitary metastatic disease (HR = 1.4, 95% CI: 1.0-2.0).

CONCLUSION

Our large, multi-institutional review indicates that both the metastatic pattern and site of DM impact OS. Polymetastatic disease and bone metastasis are associated with worse prognosis, independent of treatment received.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E1838-E1846, 2021.

Definition of locally recurrent head and neck squamous cell carcinoma: a systematic review and proposal for the Odense-Birmingham definition

PURPOSE

The objectives of this study were (1) to systematically review current definitions of head and neck squamous cell carcinoma (HNSCC) recurrence and (2) to propose a definition of locally recurrent HNSCC.

METHODS

A systematic literature review was performed according to the 'Preferred Reporting Items for Systematic Reviews and Meta-Analyses' statement in Medline, Embase, and Cochrane databases guided by the study question "What is the definition of local recurrence for patients with HN:SCC?". All retrieved studies were reviewed and qualitatively analyzed.

RESULTS

The systematic literature search resulted in 3467 publications after removal of duplicates. Forty studies were examined as full text, and a total of five were found suitable for inclusion. All five included studies dealt with definitions of second primary HNSCC and were based on the Warren and Gates Criteria; (1) each of the tumors are malignant, (2) each must be distinct, and (3) the probability of one being a metastasis of the other must be excluded. Each of the included studies added specific anatomical and/or temporal separation measures to the criteria of second primary HNSCC. We propose the definition of locally recurrent HNSCC to be: (1) Same anatomical subsite or adjacent subsite within 3 cm of the primary lesion, (2) time-interval no more than 3 years (from completed treatment of the primary lesion), and (3) same p16-status for oropharyngeal carcinomas.

CONCLUSIONS

No uniform definition of locally recurrent HNSCC currently exists. We propose the Odense-Birmingham definition based on the anatomical subsite combined with a specific measurable distance and a temporal separation of three years.

Metastatic disease in head & neck oncology

The head and neck district represents one of the most frequent sites of cancer, and the percentage of metastases is very high in both loco-regional and distant areas. Prognosis refers to several factors: a) stage of disease; b) loco-regional relapses; c) distant metastasis. At diagnosis, distant metastases of head and neck cancers are present in about 10% of cases with an additional 20-30% developing metastases during the course of their disease. Diagnosis of distant metastases is associated with unfavorable prognosis, with a median survival of about 10 months. The aim of the present review is to provide an update on distant metastasis in head and neck oncology. Recent achievements in molecular profiling, interaction between neoplastic tissue and the tumor microenvironment, oligometastatic disease concepts, and the role of immunotherapy have all deeply changed the therapeutic approach and disease control. Firstly, we approach topics such as natural history, epidemiology of distant metastases and relevant pathological and radiological aspects. Focus is then placed on the most relevant clinical aspects; particular attention is reserved to tumours with distant metastasis and positive for EBV and HPV, and the oligometastatic concept. A substantial part of the review is dedicated to different therapeutic approaches. We highlight the role of immunotherapy and the potential effects of innovative technologies. Lastly, we present ethical and clinical perspectives related to frailty in oncological patients and emerging difficulties in sustainable socio-economical governance.

Modern radiotherapy for head and neck cancer

Radiation therapy (RT) plays a key role in curative-intent treatments for head and neck cancers. Its use is indicated as a sole therapy in early stage tumors or in combination with surgery or concurrent chemotherapy in advanced stages. Recent technologic advances have resulted in both improved oncologic results and expansion of the indications for RT in clinical practice. Despite this, RT administered to the head and neck region is still burdened by a high rate of acute and late side effects. Moreover, about 50% of patients with high-risk disease experience loco-regional recurrence within 3 years of follow-up. Therefore, in recent decades, efforts have been dedicated to optimize the cost/benefit ratio of RT in this subset of patients. The aim of the present review was to highlight modern concepts of RT for head and neck cancers considering both the technological advances that have been achieved and recent knowledge that has informed the biological interaction between radiation and both tumor and healthy tissues.