Oligometastatic head and neck cancer: Comprehensive review

Future directions in the evaluation and management of newly diagnosed metastatic cancer

There is much debate regarding optimal selection in patients with metastatic cancer who should undergo local treatment (surgery or radiation treatment) to the primary tumor and/or metastases. Additionally, the optimal treatment of newly diagnosed metastatic cancer is largely unclear. Current prognostication systems to best inform these clinical scenarios are limited, as all metastatic patients are grouped together as having Stage IV disease without further incorporation of patient and disease-specific covariates that significantly impact patient outcomes. Therefore, improving current prognostic scoring systems and incorporation of these covariates is essential to best individualize treatment for patients with metastatic cancer. In this narrative review article, we provide a detailed review of prognostication systems that can be used for both the site of metastasis and primary site to best tailor treatment in these patients. Additionally, we discuss the incorporation and ongoing developments in radiographic, genomic, and biostatistical techniques that can be used as prognostication tools.

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.

Cost-minimization analysis of the GORTEC 2014-04 randomized phase II study of stereotactic ablative radiotherapy (SABR) or chemotherapy-SABR in oligometastatic head and neck cancer

PURPOSE

The randomized phase II GORTEC 2014-04 and French Head and Neck Intergroup study showed deeper deterioration of the quality of life (HRQoL) and dramatically higher severe toxicity rates with similar overall survival rates using chemo-SABR compared to SABR alone in oligometastatic head and neck cancer (HNSCC) patients. We evaluated the costs associated with SABR-alone versus chemo-SABR and their associated costs (transportation, hospitalizations, etc).

MATERIALS AND METHODS

69 HNSCC patients with 1-3 oligometastases and a controlled primary were randomized from September 2015 to October 2022. HRQoL by the QLQ-C30, QLQ-HN35, descriptive EQ5D-3L and visual EQ-VAS self-rated questionnaires were completed for clinical benefit and economic utility appraisal. Direct medical treatment-related costs (radiotherapy, anticancer drugs, hospital stays, serious adverse event management, medical imaging, biological surveillance and medical transports) were analyzed from randomization until 12 months (M12, including per protocol and salvage treatments) or death. Utility index scores and deterioration rates were used. Based on equivalent outcomes, a cost-minimization analysis was performed..

RESULTS

Median EQ-5D-3L utility index scores were 0.84 at baseline and 0.87 at M12 for SABR-alone; corresponding to 0.85 and 0.57 for chemo-SABR. Rates of patients free of definitive EQ-VAS deterioration at M12 were 76.9 % and 63.8 % for SABR-alone and chemo-SABR. Mean quality-adjusted PFS was 12.1 and 11.0 months with SABR-alone and chemo-SABR. The mean total costs from the French Public health system perspective were €8,498 ± 3,599 for SABR-alone, and €48,034 ± 58,228 for chemo-SABR (p < 10-4). Sensitivity analyses confirmed cost savings around €35,000-€40,000 per patient using SABR-alone. Anticancer drugs and hospital stays were cost drivers. The economic burden increased by 269 ± 66 % with chemo-SABR compared to SABR-alone (p < 10-4).

CONCLUSIONS

in addition to clinical benefits, SABR-alone appears as the least costly option (by a factor of 5) for the management of oligometastases from HNSCC.

Primary site surgical resection in cM1 oral cavity squamous cell carcinoma

Objective

To investigate primary site surgical resection and overall survival (OS) in clinically distantly metastatic (cM1) oral cavity squamous cell carcinoma (OCSCC).

Methods

The 2006-2018 National Cancer Database was queried for patients presenting with cM1 OCSCC who underwent chemotherapy. Binary logistic, Kaplan-Meier, and multivariable Cox proportional hazards regression models were implemented.

Results

Of 278 patients satisfying inclusion criteria, 139 (50.0%) underwent chemotherapy alone, 80 (28.8%) underwent chemoradiotherapy, 25 (9.0%) underwent surgical resection + adjuvant chemotherapy, and 34 (12.2%) underwent surgical resection + adjuvant chemoradiotherapy; 5-year OS was 9.4%, 15.2%, 8.3%, and 23.8%, respectively (p < .001). Compared with those not undergoing surgical resection, patients undergoing surgical resection underwent radiotherapy more frequently (57.6% vs. 36.5%) but multiple-agent chemotherapy less frequently (40.7% vs. 74.4%) (p < .005). Twenty-one (36.2%) patients undergoing surgical resection had positive surgical margins. Academic facility (adjusted odds ratio [aOR] 3.19, 95% CI 1.54-6.62) and Charlson-Deyo comorbidity score ≥1 (aOR 2.82, 95% CI 1.25-6.32, p < .025) were associated with increased odds of undergoing surgical resection. Compared with chemotherapy alone, chemoradiotherapy (adjusted hazard ratio [aHR] 0.56, 95% CI 0.38-0.83) and surgical resection + adjuvant chemoradiotherapy (aHR 0.37, 95% CI 0.21-0.66) were associated with higher OS (p < .005). Immunotherapy (aHR 0.48, 95% CI 0.28-0.81, p = .006) was also independently associated with higher OS.

Conclusion

A minority of patients with cM1 OCSCC underwent primary site surgical resection. Despite the high rate of positive surgical margins, surgical resection + adjuvant chemoradiotherapy was associated with higher OS than chemotherapy alone, chemoradiotherapy, or surgical resection + adjuvant chemotherapy. Definitive local therapy may benefit select patients with cM1 OCSCC.Level of evidence: 4.

HyperArcTM volumetric modulated arc therapy for hypopharyngeal cancer with solitary recurrence in the cervical vertebra: A case report and literature review

RATIONALE

It is difficult to reirradiate head and neck cancers because of the toxicity from previous radiation dose delivery. Conventional volumetric modulated arc therapy (VMAT) and intensity-modulated radiation therapy often have poor target coverage. The new HyperArcTM VMAT (HA-VMAT) planning approach reportedly has better target coverage, higher conformity, and can spare normal organs compared to conventional VMAT; however, research on recurrent head and neck cancers is limited. Here, we report the clinical outcomes of HA-VMAT for previously irradiated hypopharyngeal cancer with solitary recurrence in the first cervical vertebra (C1).

PATIENT CONCERNS

A 52-year-old Asian male was diagnosed with a hypopharyngeal cancer. The patient received concurrent chemoradiotherapy with a radiation dose of 70 Gy in 33 fractions and achieved complete clinical response. Two years later, solitary recurrence was observed in the C1 vertebra.

DIAGNOSES

Solitary recurrence in the C1 vertebra.

INTERVENTIONS

Owing to concerns regarding the toxicity to adjacent organs, we decided to use HA-VMAT to achieve better tumor coverage and critical organ sparing.

OUTCOMES

Tumor regression was observed on the imaging. At 9 months follow-up, the patient was disease-free and had no late toxicities.

LESSONS

This is the first report regarding the clinical outcomes of HA-VMAT for previously irradiated hypopharyngeal cancer with solitary recurrence over the C1 vertebra. HA-VMAT achieves highly conformal dose distribution and excellent sparing of critical organs. There was a favorable initial clinical response with no toxicity. Long-term follow-up is essential in such cases.

Stereotactic Body Radiotherapy in Recurrent and Oligometastatic Head and Neck Tumours

The treatment of head and neck cancers (HNCs) encompasses a complex paradigm involving a combination of surgery, radiotherapy, and systemic treatment. Locoregional recurrence is a common cause of treatment failure, and few patients are suitable for salvage surgery. Reirradiation with conventional radiation techniques is challenging due to normal tissue tolerance limits and the risk of significant toxicities. Stereotactic body radiotherapy (SBRT) has emerged as a highly conformal modality that offers the potential for cure while limiting the dose to surrounding tissue. There is also growing research that shows that those with oligometastatic disease can benefit from curative intent local ablative therapies such as SBRT. This review will look at published evidence regarding the use of SBRT in locoregional recurrent and oligometastatic HNCs.

Primary Site Surgery in Distantly Metastatic Oropharyngeal Squamous Cell Carcinoma

OBJECTIVES

Determine if intensive local therapy (i.e., local surgery or radiation) has a survival benefit for patients presenting with distantly metastatic oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

Retrospective population-based cohort study of patients in the National Cancer Database presenting with distantly metastatic OPSCC. Overall survival (OS) was compared for patients receiving systemic therapy alone or in combination with local surgery or curative dose radiation, controlling for various clinicodemographic factors.

RESULTS

Between 2010 and 2015, 627 patients presented with newly diagnosed, metastatic OPSCC and an initial treatment course including systemic chemotherapy. Multivariable analysis demonstrated that local radiation therapy was independently associated with improved OS (OR 0.64, CI [0.51-0.81]); local surgery was not independently associated with improved OS (OR 0.99, CI [0.65-1.53]). Higher T stages were associated with worse OS (OR 1.69, CI [1.14-2.50] for T3 and OR 1.77, CI [1.22-2.58] for T4 compared to T1). HPV-positive (HPV+) tumors were associated with improved OS compared to HPV- (OR 0.79, CI [0.64-0.97]). Multiagent chemotherapy was associated with improved OS compared to single-agent (OR 0.78, CI [0.62-1.00]). The best survival for the entire cohort and for HPV+ patients was for radiation with systemic therapy and the worst survival for systemic therapy alone.

CONCLUSIONS

Curative dose local radiotherapy in addition to systemic therapy is associated with improved OS compared to systemic therapy alone in patients presenting with distantly metastatic OPSCC. There is not a significant survival benefit for local surgery in addition to systemic therapy in this patient population, regardless of HPV status.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:2243-2251, 2024.

Identifying optimal candidates for primary tumor surgery in patients with metastatic head and neck cancer

Background

Primary tumor surgery (PTS) may enhance survival among part of patients with metastatic head and neck cancer (mHNC). Herein, a predictive model was needed to construct to identify who can gain benefit remarkably from tumor resection.

Methods

Data of patients with mHNC were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. The best cut-off value of age were analyzed using the X-tile software. One-to-one PSM, Kaplan-Meier method, and log-rank test were performed for survival analysis.The independent factors determined using the multivariate Cox proportional hazard regression were used to construct the nomogram.

Results

A total of 1,614 patients diagnosed with mHNC were included; among them, 356 (22.0%) underwent a surgical procedure for the excision of the primary tumor. cancer-specific survival (CSS) was remarkably prolonged in the PTS group relative to the non-PTS group following PSM [Median:19 months vs. 9 months; hazard ratio (HR) 0.52, P < 0.001]. Patients with mHNC who were younger than 52 years old, had well-differentiated tumors, had T1 and N0 stages, and were married at the time of the study may have significantly benefited from PTS. In addition, we constructed a nomogram based on the factors that independently affect the CSS in multivariate Cox analysis. The nomogram showed excellent discrimination in both the training and validation sets (AUC: 0.732 and 0.738, respectively).

Conclusion

A practical predictive model was constructed to determine the appropriate patients with mHNC, who would benefit from surgical resection.

Clinical implication of neck dissection for metastatic lymph nodes originating from non-head and neck regions

BACKGROUND

Cervical lymph node metastasis (CLNM) from remote primary sites is rare in head and neck cancer. The efficacy of neck dissection is still being investigated for therapeutic benefits of local management in oligometastasis from non-head and neck cancer.

OBJECTIVES

To evaluate the clinical efficacy of neck dissection (ND) in CLNM from distant primary cancers and identify factors contributing to improved survival.

MATERIALS AND METHODS

This retrospective case-control study enrolled patients who underwent ND for CLNM from distant primary cancer at Asan Medical Centre between January 2010 and December 2020. We analysed overall survival and association between clinical covariate and survival.

RESULTS

The study included 31 (14 males, 17 females) among 114 patients. Ovarian cancer was the most common primary malignancy (32.3%). Patients with fewer than three metastatic lymph nodes, without extranodal extension and with adjuvant therapy after surgery had better survival rates.

CONCLUSION AND SIGNIFICANCE

In patients with CLNM from a distant primary cancer, ND is beneficial as local treatment. And adequate selection of patients for ND is pivotal to improve prognosis.

Management of head and neck carcinomas with synchronous or metachronous oligometastatic disease: Role of locoregional radiotherapy and metastasis-directed radiotherapy

Head and neck carcinomas are initially metastatic in about 15% of cases. Radiotherapy is a cornerstone in the multimodal strategy at the locoregional phase. In patients with head and neck cancer, often heavily pretreated and with comorbidities, who relapse locoregionally or at distant sites, radiotherapy has also become increasingly important at the metastatic phase. Data on the optimal sequence of systemic treatments and metastasis-directed treatments including stereotactic irradiation are still lacking. Several randomized head and neck trials have been initiated that should provide important answers, including one recent GORTEC trial.

Correlation Between Oligometastatic Tumor in Two Other Visceral Organs and Prognosis in Patients With Brain Metastases

Background and Objective: A recent report indicated that metastases to other body organs commonly develop after stereotactic body radiation treatment for cure in patients with oligometastases (OGM) confined to one organ. This study was undertaken to determine if the presence of metastatic disease in two other visceral organs (TVO) in patients with conventionally treated brain metastases (BRM) was associated with poorer prognosis. Methods: This retrospective clinical investigation included 26 patients treated for palliation of OGM-BRM between May 1996 and February 2020. These individuals were classified according to the presence (13 patients) or absence (13 patients) of metastases in TVO. Results: With an overall mean follow-up of 16 months, 20 patients were deceased, and 6 patients were alive. The median survivals for the OGM-BRM-TVO and non-OGM-BRM-TVO subsets were 4 and 12 months, respectively; the corresponding crude survival rates at 12 months were 0% and 46% (p < 0.01). Subgroup analysis correlating prognosis to the number of BRM (single vs. multiple) and OGM-BRM categories (synchronous vs. metachronous) failed to reveal a survival advantage favoring a certain subgroup. Conclusion: Although the evidence is speculative, we believe that an aggressive disease condition is more likely present in patients with OGM-BRM-TVO. With the notion of an overall poor survival, we suggest a more tailored, less or nonharmful management approach (i.e., palliative therapy or hospice) for this particular patient cohort.

Novel HPV Associated Oropharyngeal Squamous Cell Carcinoma Surveillance DNA Assay Cost Analysis

OBJECTIVES

We aim to propose a modified surveillance strategy using a novel blood assay that detects plasma circulating tumor-specific HPV DNA with reported 100% NPV and 94% PPV as the main method of detection to understand the cost implications of potentially avoiding routine imaging and surveillance visits at our institution.

METHODS

We performed a retrospective chart review focusing on recurrences in p16+ patients with OPSCC and defined two surveillance strategies: "Strategy A", follow-up visits with flexible laryngoscopy (FL) plus regular imaging studies; "Strategy B", follow-up visits with FL plus regular NavDx assays and imaging used at the discretion of the physician(s) in cases of high clinical suspicion.

RESULTS

Of the p16+ OPSCC patients (n = 214), 23 had confirmed recurrence (11%). Standard work-flow model determined 72 imaging studies and 2198 physical examinations with FL were needed to detect one recurrence. Potential individual patient cost reduction during surveillance was 42%.

CONCLUSION

Implementing NavDx for HPV + OPSCC surveillance would benefit patients by reducing costs and unnecessary diagnostic testing.

LEVEL OF EVIDENCE

Step/Level 3 Laryngoscope, 133:3006-3012, 2023.

Expanding the role of combined immunochemotherapy and immunoradiotherapy in the management of head and neck cancer (Review)

Immunotherapy has become one of the most promising approaches in tumor therapy, and there are numerous associated clinical trials in China. As an immunosuppressive tumor, head and neck squamous cell carcinoma (HNSCC) carries a high mutation burden, making immune checkpoint inhibitors promising candidates in this field due to their unique mechanism of action. The present review outlines a comprehensive multidisciplinary cancer treatment approach and elaborates on how combining immunochemotherapy and immunoradiotherapy guidelines could enhance clinical efficacy in patients with HNSCC. Furthermore, the present review explores the immunology of HNSCC, current immunotherapeutic strategies to enhance antitumor activity, ongoing clinical trials and the future direction of the current immune landscape in HNSCC. Advanced-stage HNSCC presents with a poor prognosis, low survival rates and minimal improvement in patient survival trends over time. Understanding the potential of immunotherapy and ways to combine it with surgery, chemotherapy and radiotherapy confers good prospects for the management of human papillomavirus (HPV)-positive HNSCC, as well as other HPV-positive malignancies. Understanding the immune system and its effect on HNSCC progression and metastasis will help to uncover novel biomarkers for the selection of patients and to enhance the efficacy of treatments. Further research on why current immune checkpoint inhibitors and targeted drugs are only effective for some patients in the clinic is needed; therefore, further research is required to improve the overall survival of affected patients.

Patterns of Distant Metastasis in Head and Neck Cancer in a Tertiary Care Centre

Objectives/Hypothesis To find out the frequency and location of distant metastasis in head and neck malignancies. Our study also aims to find out the most common site leading to distant metastasis and the management of these distant metastasis cases. Methods 1558 patients treated for head and neck malignancy between 2017 and 2021 were retrospectively reviewed. The frequency and proportions were used to produce descriptive statistics. Results The highest number of head and neck malignancy cases were reported in the oral cavity which included 943 cases (60.52%). Patients with distant metastasis (M1) accounted for 4.73 percent of all cases (n = 90). Nasopharyngeal malignancy cases showed the highest M1 frequency (29.03%), whereas oral cavity patients had the lowest frequency (2.75%). The most common site of distant metastasis was in the lung (64%) followed by bone (18%) and the liver (11%). CT scan of the neck and thorax was the most commonly used diagnostic modality. The most common histopathological finding was squamous cell carcinoma (85%). Multimodality treatment was employed for most of the detected cases. Conclusion Distant metastasis at presentation is rare in head and neck cancer. The rate of distant metastasis in the present study was 4.73%, with the lung being the most common site. The overall survival of these patients depends on a variety of factors and more studies are needed in this regard.

Advancing Immunotherapies for HPV-Related Cancers: Exploring Novel Vaccine Strategies and the Influence of Tumor Microenvironment

The understanding of the relationship between immunological responses and cancers, especially those related to HPV, has allowed for the study and development of therapeutic vaccines against these neoplasias. There is a growing number of studies about the composition and influence of the tumor microenvironment (TME) in the progression or establishment of the most varied types of cancer. Hence, it has been possible to structure immunotherapy approaches based on therapeutic vaccines that are even more specific and directed to components of TME and the immune response associated with tumors. Among these components are dendritic cells (DCs), which are the main professional antigen-presenting cells (APCs) already studied in therapy strategies for HPV-related cancers. On the other hand, tumor-associated macrophages are also potential targets since the profile present in tumor infiltrates, M1 or M2, influences the prognosis of some types of cancer. These two cell types can be targets for therapy or immunomodulation. In this context, our review aims to provide an overview of immunotherapy strategies for HPV-positive tumors, such as cervical and head and neck cancers, pointing to TME immune cells as promising targets for these approaches. This review also explores the potential of immunotherapy in cancer treatment, including checkpoint inhibitors, cytokine immunotherapies, immunotherapy vaccines, and cell therapies. Furthermore, it highlights the importance of understanding the TME and its effect on the design and achievement of immunotherapeutic methods.

Durable complete remission with local therapies after neoadjuvant and adjuvant nivolumab in recurrent/metastatic head and neck cancer

Up to 10-15% of patients with first-line recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) present with platinum-refractory disease. The anti-PD1 nivolumab is the first therapeutic option in this setting achieving a 19.2% objective response rate and a 7.7-month median overall survival (OS). Given the poor prognosis of platinum-refractory patients, those showing slow progressive disease with no functional status deterioration should maintain nivolumab beyond progression in the absence of severe or unmanageable toxicities. Another strategy is to use local therapies such as radiotherapy and surgical tumor resection in cases of oligometastatic or oligoprogressive disease. Both strategies may significantly improve disease control and OS in these populations. We present the case of a patient with platinum-refractory disease treated with first-line nivolumab beyond progression who achieved a durable complete response after palliative radiation and surgical resection of five tumor lesions. To our knowledge, this is the first reported case of an R/M HNSCC treated with such a strategy outside a clinical trial and contributes to the evidence for combining anti-PD1 agents and local therapies in selected patients with R/M HNSCC.

The oligometastatic setting in HNSCC: A critical review by the Rete Oncologica Piemonte e Valle d'Aosta multidisciplinary team

INTRODUCTION

The oligometastatic disease is a low burden metastatic disease that might still benefit from curable treatment. Squamous cell carcinoma of the head and neck (HNSCC) is a complex group of malignancies, with high rates of loco-regional recurrences. Distant metastases are less frequent, and a single or few deposits are often observed (oligometastatic disease). The optimal management of oligometastatic HNSCC remains to be defined.

MATERIALS AND METHODS

Key references were derived from a PubMed query. Hand searching and clinicaltrials.gov were also used.

RESULTS

This paper contains a narrative report and a critical discussion of the available evidence on the management of oligometastatic HNSCC patients, with a focus on metastasis-directed therapy (MDT), particularly stereotactic ablative radiotherapy (SABR).

CONCLUSIONS

in line with literature data, the multidisciplinary evaluation emerged as the key element in the management of oligometastatic HNSCC patients.

Clinical outcomes in relapsed oropharyngeal cancer after definitive (chemo) radiotherapy

OBJECTIVES

To report clinical outcomes of relapsed oropharyngeal squamous cell carcinoma (OPSCC) after definitive intensity-modulated (chemo)radiotherapy [(C)RT].

MATERIALS AND METHODS

Data for all relapsed patients treated for OPSCC with definitive (C)RT between 2010 and 2016 were collected. Primary end-point was post-failure survival (PFS).

RESULTS

Overall, 273 OPSCC patients completed definitive (C)RT. Of these, 42 cases (n = 26 human papilloma virus (HPV)-negative; n = 16 HPV-positive) had relapsed (n = 23 persistent disease; n = 19 recurrent disease) and were included in the final analysis. Two-year PFS for the entire population was 30.6%; 20.5% for HPV-negative and 43.8% for HPV-positive patients. Salvage curative surgery was associated with a significantly higher 2 years PFS rate (56.2%) compared with palliative treatment (22.9%) and best supportive care (0%) (p < 0.001). A positive trend in 2 years PFS was recorded in the early complete response cases (49.5%) versus patients who did not achieve a complete response within 3 months of the end of (C)RT (23.0%) (p = 0.11).

CONCLUSION

A higher PFS rate is achieved when relapsed OPSCC cases are treated with salvage curative intent. HPV-positive disease and early complete response within 3 months from the end of (C)RT may be related to better PFS.

Radioimmunotherapy in HPV-Associated Head and Neck Squamous Cell Carcinoma

HPV-associated head and neck squamous cell carcinoma (HNSCC) is a cancer entity with unique biological and clinical characteristics that requires more personalized treatment strategies. As the backbone of conventional therapeutics, radiation is now harnessed to synergize with immunotherapy in multiple malignancies. Accumulating preclinical and clinical data have suggested the potential of radioimmunotherapy in eliciting local and systemic anti-tumor response via direct killing of tumor cells and immunogenic cell death. However, this effect remains uncertain in HPV-associated HNSCC. Owing to its intrinsic radiosensitivity and distinct tumor microenvironment, HPV-associated HNSCC may represent a good candidate for radioimmunotherapy. In this review, we provide a detailed illustration of the biology, the genomic features, and immune landscapes of HPV-associated HNSCC that support the synergism between radiation and immune agents. The interaction between radiotherapy and immunotherapy is described. We also highlight the present evidence as well as ongoing trials using different combination strategies in the recurrent/metastatic or definitive settings. In addition, we have summarized the challenges and outlook for future trial design, with special emphasis on radiotherapy optimization and novel therapeutic options to incorporate.

Definitive local therapy to head and neck squamous cell carcinoma with distant metastasis

Objectives

Data on the efficacy of including definitive local therapy to the primary site for head and neck squamous cell carcinoma (HNSCC) patients with synchronous distant metastasis are lacking. In multiple different solid tumor types, there has been benefit when using systemic therapy followed by local consolidative therapy (stereotactic ablative radiotherapy or surgery) directed at metastases. We proposed to retrospectively evaluate patients at our institution that received definitive treatment to the primary.

Methods

Single institution retrospective study evaluating 40 patients with metastatic HNSCC treated with definitive surgery (55%) or chemoradiation (45%) to the primary site from 2000 to 2020. The major endpoints were overall survival (OS) and progression-free survival (PFS) for the total population and multiple sub-groups. Some variables were evaluated with multiple covariates Cox model.

Results

The median PFS was 8.6 months (95% CI, 6.4-11.6), and OS was 14.2 months (95% CI, 10.9-27.5). In 28% of patients that received induction therapy, there was a twofold increase in median overall survival to 27.5 months. In the 33% of patients that received anti-PD-1 mAb as part of their treatment course, the median OS was significantly increased to 41.7 months (95% CI, 8.7-NR) versus 12.1 months (95% CI, 8.4-14.4) with a 5-year OS of 39%. Multivariate analysis for OS showed significance for age at diagnosis, use of IO, and number of metastatic sites.

Conclusion

We observed impressive survival outcomes in metastatic HNSCC patients treated with definitive local therapy to the primary site in addition to induction and/or immunotherapy. Further study is warranted.Level of Evidence: 3.

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.

Curative intent Stereotactic Ablative Radiation Therapy (SABR) for treatment of lung oligometastases from head and neck squamous cell carcinoma (HNSCC): a multi-institutional retrospective study

OBJECTIVES

The aim of this retrospective study was to assess outcomes of SABR for metachronous isolated lung oligometastases from HNSCC.

METHODS

For patients who developed isolated, 1 or 2 lungs lesions (<5cm) consistent with metastases from HNSCC, the indication of SABR was validated in a multidisciplinary tumor board. All patients were monitored by CT or PET CT after SABR (Stereotactic Ablative Body Radiation) for HNSCC.

RESULTS

Between November 2007 and February 2018, 52 patients were treated with SABR for metachronous lung metastases. The median time from the treatment of the primary HNSCC to the development of lung metastases was 18 months (3-93). The cohort's median age was 65.5 years old (50-83). The vast majority (94.2%) received 60 Gy in three fractions. Forty-one patients (78.5%) presented a solitary lung metastasis, while 11 patients (21.5%) had two lung metastases. With a median follow-up of 45.3 months, crude local and metastatic control rates were 74 and 38%, respectively. 1 year and 2 year Overall Survival (OS) were 85.8 and 65.9%, respectively. The median OS was 46.8 months. About one-fourth of patients were retreated by SABR for distant pulmonary recurrence. The treatment was well tolerated with only one patient who reported ≥ grade 3 toxicity (1.9%).

CONCLUSION

In selected metastatic HNSCC patients, early detection and treatment of lung metastases with SABR is effective and safe. Prospective studies are required to validate this potential shift.

ADVANCES IN KNOWLEDGE

Patients with oligometastases and controlled primary HNSCC seem to benefit from metastasis directed therapies.

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.

Abscopal effect as part of treatment of oligometastatic head and neck cancer: A case report

A 66-year-old man with hypopharyngeal carcinoma with a single bone metastasis was treated with definitive chemo/radiotherapy omitting local treatment of the single bone lesion. He remained relapse-free for 6 years. We have concluded that radiotherapy-dependent abscopal effect might have allowed to avoid ablative treatment of metastatic site.

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.

Prognosis and management of recurrent and/or metastatic head and neck adenoid cystic carcinoma

Adenoid cystic carcinoma (ACC) is a rare tumor, usually arising in the salivary gland, accounting for 1% of all head and neck cancers. ACC may have a long-term poor prognosis, as about 40% of radically treated patients will recur locoregionally and up to 60% will develop distant metastasis. Factors influencing risk of recurrence have been well studied, but few data exist about prognostic factors in Recurrent/Metastatic (RM) setting. Moreover, treatment of RM ACC is often a challenge for clinicians, in the context of a rare disease, which may have an indolent clinical behavior or less frequently a quicker growth and with a paucity of available clinical trials. This review critically analyzes pathological and molecular prognostic factors in RM ACC and make an overview on actual therapeutic choices and future direction of therapy. Recognized prognostic factors in RM ACC are the presence and site of distant metastasis (lung vs other), the presence of nodal metastasis and of extranodal extension, skull base recurrence, disease free interval, lymphovascular invasion, solid histotypes and grading of disease, and the presence of mutation of NOTCH1 family, PI3K, and TP53. Due to disappointing results with chemotherapy, new approaches are under study, also on the basis of biomolecular research. Ongoing clinical trials are evaluating treatment targeting MYB and NOTCH1 alterations, immunotherapy or combination of targeted treatments and immune checkpoint inhibitors.

Radiotherapy and Immunotherapy for Head and Neck Cancer: Current Evidence and Challenges

Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment over the past decade. However, although the immune landscape suggests a strong rationale for the use of these agents in patients with head and neck squamous cell carcinoma, the available clinical evidence indicates that most patients currently do not respond to ICI monotherapy. Radiotherapy is a primary treatment modality for many patients with locally advanced head and neck cancer. While ionizing radiation traditionally has been thought to act in a purely cytotoxic fashion, a growing body of preclinical studies have demonstrated additional profound immunomodulatory effects. Consequently, there has been a surge of interest in the potential synergy between radiotherapy and immunotherapy, both the potential for radiotherapy to augment the systemic anti-tumor immune response and the potential for immunotherapy to improve in-field tumor response to radiation. In this review, we summarize the current preclinical and clinical evidence for radioimmunotherapy, with a particular focus on studies directly relevant to head and neck squamous cell carcinoma, as well as existing challenges and future directions for this emerging field.

Metastasis-directed stereotactic body radiation therapy in the management of oligometastatic head and neck cancer

INTRODUCTION

Recently major efforts have been made to define the oligometastatic setting, but for head and neck cancer (HNC) limited data are available. We aimed to evaluate outcome of oligometastatic HNC treated with Stereotactic body radiotherapy (SBRT) as metastasis-directed therapy.

MATERIALS AND METHODS

We analyzed patients treated with SBRT on a maximum of five oligometastases from HNC, in up to two organs. Concomitant treatment was allowed. End points were toxicity, local control of treated metastases (LC), progression-free survival (PFS) and overall survival (OS).

RESULTS

48 consecutive patients and 71 lesions were treated. With a follow-up of 20.2 months, most common primary tumors were larynx (29.2%) and salivary glands (29.2%), while common site of metastases was lung (59.1%). Median dose was 48 Gy (21-75) in 3-8 fractions. Treatment was well tolerated, with two patients reporting mild pain and nausea. LC rates at 1 and 2 years were 83.1% and 70.2%. Previous local therapy (HR 4.97; p = 0.002), oligoprogression (HR 4.07; p = 0.031) and untreated metastases (HR 4.19; p = 0.027) were associated with worse LC. PFS at 1 and 2 years were 42.2% and 20.0%. Increasing age (HR 1.03; p = 0.010), non-adenoid cystic carcinoma (HR 2.57; p = 0.034) and non-lung metastases (HR 2.20; p = 0.025) were associated with worse PFS. One- and 2-years OS were 81.0% and 67.1%. Worse performance status (HR 2.91; p = 0.049), non-salivary primary (HR 19.9; p = 0.005), non-lung metastases (HR 2.96; p = 0.040) were correlated with inferior OS.

CONCLUSIONS

SBRT can be considered a safe metastasis-directed therapy in oligometastatic HNC. Efficacy of the treatment seems to be higher when administered upfront in the management of metastatic disease; however, selection of patients need to be improved due to the relevant risk of appearance of new metastatic site after SBRT.

Oligometastatic Disease Management: Finding the Sweet Spot

Hematogenous dissemination represents a common manifestation of squamous cell carcinoma of the head and neck, and the recommended therapeutic options usually consist of systemically administered drugs with palliative intent. However, mounting evidence suggests that patients with few and slowly progressive distant lesions of small size may benefit from various local ablation techniques, which have already been established as standard-of-care modalities for example in colorectal and renal cell carcinomas and in sarcomas. In principle, serving as radical approaches to eradicate cancer, these interventions can be curative. Their impact on local control and overall survival has been shown in numerous retrospective and prospective studies. The term oligometastatic refers to the number of distant lesions which should generally not surpass five in total, ideally in one organ. Currently, surgical resection remains the method of choice supported by the majority of published data. More recently, stereotactic (ablative) body radiotherapy (SABR/SBRT) has emerged as a viable alternative. In cases technically amenable to such local interventions, several other clinical variables need to be taken into account also, including patient-related factors (general health status, patient preferences, socioeconomic background) and disease-related factors (primary tumor site, growth kinetics, synchronous or metachronous metastases). In head and neck cancer, patients presenting with late development of slowly progressive oligometastatic lesions in the lungs secondary to human papillomavirus (HPV)-positive oropharyngeal cancer are the ideal candidates for metastasectomy or other local therapies. However, literature data are still limited to say whether there are other subgroups benefiting from this approach. One of the plausible explanations is that radiological follow-up after primary curative therapy is usually not recommended because its impact on survival has not been unequivocal, which is also due to the rarity of oligometastatic manifestations in this disease. At the same time, aggressive treatment of synchronous metastases early in the disease course should be weighed against the risk of futile interventions in a disease with already multimetastatic microscopic dissemination. Therefore, attentive treatment sequencing, meticulous appraisal of cancer extension, refinement of post-treatment surveillance, and understanding of tumor biology and kinetics are crucial in the management of oligometastases.

Immunomodulatory Effects of Radiotherapy

Radiation therapy (RT), an integral component of curative treatment for many malignancies, can be administered via an increasing array of techniques. In this review, we summarize the properties and application of different types of RT, specifically, conventional therapy with x-rays, stereotactic body RT, and proton and carbon particle therapies. We highlight how low-linear energy transfer (LET) radiation induces simple DNA lesions that are efficiently repaired by cells, whereas high-LET radiation causes complex DNA lesions that are difficult to repair and that ultimately enhance cancer cell killing. Additionally, we discuss the immunogenicity of radiation-induced tumor death, elucidate the molecular mechanisms by which radiation mounts innate and adaptive immune responses and explore strategies by which we can increase the efficacy of these mechanisms. Understanding the mechanisms by which RT modulates immune signaling and the key players involved in modulating the RT-mediated immune response will help to improve therapeutic efficacy and to identify novel immunomodulatory drugs that will benefit cancer patients undergoing targeted RT.

Challenges in Combining Immunotherapy with Radiotherapy in Recurrent/Metastatic Head and Neck Cancer

Immunotherapy with immune checkpoint inhibitors (ICI) has recently become a standard part of the treatment of recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC), although the response rates are low. Numerous preclinical and clinical studies have now illuminated several mechanisms by which radiotherapy (RT) enhances the effect of ICI. From RT-induced immunogenic cancer cell death to its effect on the tumor microenvironment and vasculature, the involved mechanisms are diverse and intertwined. Moreover, the research of these interactions is challenging because of the thin line between immunostimulatory and the immunosuppressive effect of RT. In the era of active research of immunoradiotherapy combinations, the significance of treatment and host-related factors that were previously seen as being less important is being revealed. The impact of dose and fractionation of RT is now well established, whereas selection of the number and location of the lesions to be irradiated in a multi-metastatic setting is something that is only now beginning to be understood. In addition to spatial factors, the timing of irradiation is as equally important and is heavily dependent on the type of ICI used. Interestingly, using smaller-than-conventional RT fields or even partial tumor volume RT could be beneficial in this setting. Among host-related factors, the role of the microbiome on immunotherapy efficacy must not be overlooked nor can we neglect the role of gut irradiation in a combined RT and ICI setting. In this review we elaborate on synergistic mechanisms of immunoradiotherapy combinations, in addition to important factors to consider in future immunoradiotherapy trial designs in R/M 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.