Refining Patient Selection for Reirradiation of Head and Neck Squamous Carcinoma in the IMRT Era: A Multi-institution Cohort Study by the MIRI Collaborative

Re-irradiation versus systemic therapy for the management of local-regionally recurrent head and neck cancer

PURPOSE

The optimal management of local-regionally recurrent head and neck cancer that is not amenable to surgical resection is uncertain. We sought to compare outcomes among patients treated with and without re-irradiation in this setting.

METHODS AND MATERIALS

A review of institutional registries identified 65 patients with local-regionally recurrent squamous cell carcinoma of the head and neck who were ineligible for surgery. Forty patients (62 %) opted for re-irradiation with the remaining 25 patients (38 %) undergoing initial systemic therapy alone. All patients had measurable disease. Forty-three patients (66 %) were male and twenty-two (33 %) were female. The median age at the time of recurrence was 59 years (range, 39-84 years). The most common primary sites of disease were the oropharynx, (n = 25), oral cavity (N = 19), and nasopharynx (n = 11). The median interval from completion of prior radiation to the diagnosis of recurrent disease was 35 months (range, 2-102 months).

RESULTS

Re-irradiation improved 2-year overall survival, (32 % versus 11 %), progression-free survival (31 % versus 7 %), and local-regional control (39 % versus 3 %) compared to systemic therapy alone (p < 0.05, for both). The likelihood of developing any new grade 3+ toxicity was significantly higher among patients treated by re-irradiation compared to those treated by systemic therapy (53 % vs. 28 %, p < 0.001). There were 3 treatment-related fatalities, all of which occurred in the re-irradiation group. The incidence of grade 3+ late toxicity was 48 % and 12 % for patients in the re-irradiation and systemic therapy cohorts, respectively (p < 0.001).

CONCLUSION

Although re-irradiation improved overall survival compared to systemic therapy for appropriately selected patients with local-regionally recurrent head and neck cancer, the relatively high risk of toxicity must be considered.

Intensity-Modulated Reirradiation Therapy With Nivolumab in Recurrent or Second Primary Head and Neck Squamous Cell Carcinoma: A Nonrandomized Controlled Trial

Importance

Intensity-modulated radiation therapy (IMRT) reirradiation of nonmetastatic recurrent or second primary head and neck squamous cell carcinoma (HNSCC) results in poor progression-free survival (PFS) and overall survival (OS).

Objective

To investigate the tolerability, PFS, OS, and patient-reported outcomes with nivolumab (approved standard of care for patients with HNSCC) during and after IMRT reirradiation.

Design, Setting, and Participants

In this multicenter nonrandomized phase 2 single-arm trial, the treatment outcomes of patients with recurrent or second primary HNSCC who satisfied recursive partitioning analysis class 1 and 2 definitions were evaluated. Between July 11, 2018, and August 12, 2021, 62 patients were consented and screened. Data were evaluated between June and December 2023.

Intervention

Sixty- to 66-Gy IMRT in 30 to 33 daily fractions over 6 to 6.5 weeks with nivolumab, 240 mg, intravenously 2 weeks prior and every 2 weeks for 5 cycles during IMRT, then nivolumab, 480 mg, intravenously every 4 weeks for a total nivolumab duration of 52 weeks.

Main Outcomes and Measures

The primary end point was PFS. Secondary end points included OS, incidence, and types of toxic effects, including long-term treatment-related toxic effects, patient-reported outcomes, and correlatives of tissue and blood biomarkers.

Results

A total of 62 patients were screened, and 51 were evaluable (median [range] age was 62 [56-67] years; 42 [82%] were male; 6 [12%] had p16+ disease; 38 [75%] had salvage surgery; and 36 [71%.] had neck dissection). With a median follow-up of 24.5 months (95% CI, 19.0-25.0), the estimated 1-year PFS was 61.7% (95% CI, 49.2%-77.4%), rejecting the null hypothesis of 1-year PFS rate of less than 43.8% with 1-arm log-rank test P = .002 within a 1-year timeframe. The most common treatment-related grade 3 or higher adverse event (6 [12%]) was lymphopenia with 2 patients (4%) and 1 patient each (2%) exhibiting colitis, diarrhea, myositis, nausea, mucositis, and myasthenia gravis. Functional Assessment of Cancer Therapy-General and Functional Assessment of Cancer Therapy-Head and Neck Questionnaire quality of life scores remained stable and consistent across all time points. A hypothesis-generating trend favoring worsening PFS and OS in patients with an increase in blood PD1+, KI67+, and CD4+ T cells was observed.

Conclusions and Relevance

This multicenter nonrandomized phase 2 trial of IMRT reirradiation therapy and nivolumab suggested a promising improvement in PFS over historical controls. The treatment was well tolerated and deserves further evaluation.

Trial Registration

ClinicalTrials.gov Identifier: NCT03521570.

Human papillomavirus circulating tumor DNA assays as a mechanism for head and neck cancer equity in rural regions of the United States

The rates of human papillomavirus-positive oropharyngeal cancer (HPV-OPC) are rising worldwide and in the United States, particularly in rural regions including Appalachia. Rural areas face unique health challenges resulting in higher cancer incidence and mortality rates, and this includes HPV-OPC. The recent advent of highly sensitive liquid biopsies for the non-invasive detection of HPV-OPC recurrence (circulating tumor HPV DNA, HPV ctDNA) has been swiftly adopted as part of surveillance paradigms. Though knowledge gaps persist regarding its use and clinical trials are ongoing, the ease of collection and cost-effectiveness of HPV ctDNA make it more accessible for HPV-OPC survivors than usual surveillance methods of frequent exams and imaging. Herein, we discuss how implementing HPV ctDNA assays in rural regions of the United States provide one poignant example of how liquid biopsies can improve cancer care equity.

Re-irradiation of recurrent head and neck cancers using pulsed reduced dose rate radiotherapy: An institutional series

PURPOSE/OBJECTIVE(S)

Pulsed reduced dose rate (PRDR) radiation (RT) is a re-irradiation (Re-RT) technique that potentially overcomes dose/volume constraints in the setting of previous RT. There is minimal data for its use for recurrent or secondary primary head and neck squamous cell carcinoma (HNSCC). In this study, we report preliminary data from our institution of a consecutive cohort of HNSCC patients who received PRDR Re-RT.

MATERIALS/METHODS

Nine patients received PRDR Re-RT from August 2020 to January 2023 and had analyzable data. Intensity modulated RT was used for treatment delivery and a wait time between 20 cGy arc/helical deliveries was used to achieve the effective low dose rate. Data collected included patient demographic information, prior interventions, diagnosis, radiation therapy dose and fractionation, progression free survival, overall survival, and toxicity rates.

RESULTS

The median time to PRDR-RT from completion of initial RT was 13 months (range, 6-50 months). All but one patient underwent salvage surgery prior to PRDR-RT. The median follow-up after Re-RT was 7 months. The median OS from PRDR-RT was 7 months (range, 1-32 months). Median PFS was 7 months (range, 1-32 months). One patient (11.1 %) had acute grade 3 toxicity, and two patients (22.2 %) had late grade 3 toxicities. There were no grade 4+ toxicities.

CONCLUSION

PRDR Re-RT is a feasible treatment strategy for patients with recurrent or second primary HNSCC. Initial findings from this retrospective review suggest reasonable survival outcomes and potentially improved toxicity; prospective data is needed to establish the safety and efficacy of this technique.

Stereotactic ablative radiotherapy for treating primary head and neck cancer and locoregional recurrence: A comprehensive review of the literature

Introduction

Although stereotactic ablative radiotherapy (SABR) has advance to standard-of-care for many different indications like lung and liver malignancies, it still remains in its infancy for treating head and neck cancer. Nevertheless there is a growing body of experience and evidence, which is summarized in this review Methods A thorough search of the literature was performed and critically reviewed both for SABR as a primary treatment as well as for treating locoregionally recurrent disease in a pre-irradiated field.

Results

There exist only few prospective data published so far for treating head and neck cancer with SABR. In the primary situation especially implementing SABR as a boost after definitive radiotherapy or a single-modality for locally limited, small glottic cancer appear promising. On the other hand, SABR can be a useful modality for treating local recurrence in a pre-irradiated field. However, caution is needed in the case of proximity to a pre-irradiated carotid artery or other serial organs at risk. Usually only limited gross volumes are treated with 3-6 fractions every other day and a cumulative dose of 24-44 Gy in dedicated radiosurgery platforms or modern linacs with the possibility of online image-guidance and adequate immobilsation.

Conclusions

SABR is an innovative, effective and promising treatment modality for small targets, especially in near proximity to organs at risk or in a pre-irradiated region. Prospective trials are further needed for this technique to become standard-of care.

Clinical Results and Prognostic Factors in Boron Neutron Capture Therapy for Recurrent Squamous Cell Carcinoma of the Head and Neck Under the Japan National Health Insurance System: A Retrospective Study of the Initial 47 Patients

PURPOSE

Recurrent head and neck cancer presents a therapeutic challenge because of cumulative toxicity from initial radiation therapy, limiting reirradiation options. Boron neutron capture therapy (BNCT) offers a promising alternative, selectively delivering a radical dose to tumors while sparing adjacent normal tissue. This study investigates the initial clinical outcomes and prognostic factors associated with BNCT for recurrent squamous cell carcinoma of the head and neck.

METHODS AND MATERIALS

This retrospective analysis investigated the initial 47 patients treated with BNCT between May 2020 and February 2021 in Japan. All patients had received radiation therapy with a median dose of 70 Gy (range, 44-176) before BNCT. Median tumor size was 11 cm3 (range, 1-117 cm3), with 23% of tumors larger than 30 cm3, and 87% of patients had prior systemic therapy. The most common prescribed dose to the pharyngeal mucosa was 15 Gy-Eq (36%), followed by 18 Gy-Eq (34%). The minimum dose given to tumor was 27.4 Gy-Eq (range, 13.3-45.2). In 23 patients, 18F-fluoro-borono-phenylalanine positron emission tomography was performed within 1 week before BNCT, and the tumor-to-blood 10B ratio was 3.5 (range, 2.0-8.7).

RESULTS

Efficacy analysis revealed a 51% complete response rate and a 74% overall response rate. Disease-free survival rates at 1 and 2 years were 34.6% and 26.6%, respectively. Overall survival rates at 1 and 2 years were 86.1% and 66.5%, respectively. Multivariate analysis revealed that, among the patient characteristics, whether the lesion was mucosal had a significant effect on achieving complete response.

CONCLUSIONS

This study provided valuable insights into the early integration of BNCT into routine clinical practice, highlighting its efficacy and safety. Technical improvements are needed to ensure precise dose administration. Ongoing prospective studies, such as the phase II REBIVAL study, will further elucidate the role of BNCT in recurrent head and neck cancer.

Re-irradiation for isolated neck recurrence in head and neck tumor: impact of rN category

Unresectable, isolated lymph node recurrence after radiotherapy is rare but a candidate for re-irradiation. However, severe toxicity is anticipated. Therefore, this study aimed to explore the efficacy and toxicity of re-irradiation in isolated lymph node recurrence of head and neck lesions. We analyzed 46 patients who received re-irradiation for lymph node recurrence without local progression. The primary tumor sites included the oral cavity in 17 patients, the hypopharynx in 12, the oropharynx in seven, the larynx in three, the nasopharynx in two, and other sites. During a median follow-up time of 10 months, the median survival time was 10.6 months, and the 1-year overall survival rate was 45.5%. The 1-year local control and progression-free survival rates were 49.8% and 39.3%, respectively. According to univariate analysis, age (≥ 65 years), the interval between treatment (≥ 12 months), rN category (rN1), and gross tumor volume (GTV < 25 cm3) were predisposing factors for better survival. In the multivariate analysis, the rN category and interval were identified as statistically significant predictors. Late toxicity grade ≥ 3 occurred in four patients (8.6%). These were all Grade 5 carotid blowout syndrome, which associated with tumor invasion of the carotid artery and/ or high doses administration for the carotid artery. Small-volume rN1 tumor that recur after a longer interval is a feasible candidate for re-irradiation. However, strict patient selection and meticulous care for the carotid are required.

Multimodality treatment in recurrent/metastatic squamous cell carcinoma of head and neck: current therapy, challenges, and future perspectives

Squamous cell carcinoma of the head and neck is a complex group of diseases that presents a challenge to the clinician. The prognosis in the recurrent/metastatic disease is particularly dismal, with a median survival of approximately 12 months. Recently, the personalized and multimodal approach has increased prognosis by integrating locoregional strategies (salvage surgery and stereotactic radiotherapy) and systemic treatments (chemotherapy, immunotherapy, and target therapy). Malnutrition is a significant clinical problem that interferes with dose intensity, and thus, feeding supplementation is critical not only to increase the quality of life but also to improve overall survival. With this review, we want to emphasize the importance of the multidisciplinary approach, quality of life, and nutritional supportive care and to integrate the latest updates of predictive biomarkers for immunotherapy and future therapeutic strategies.

Stereotactic reirradiation in the treatment of head and neck cancers: A retrospective study on the long-term experience of the Oscar Lambret Center

BACKGROUND AND PURPOSE

Stereotactic radiotherapy potentially treats unresectable recurrences of previously irradiated head and neck (H&N) cancer. This study aimed to assess its efficacy and safety and evaluate prognostic factors.

MATERIALS AND METHODS

We conducted a large retrospective series that included 110 patients who had undergone 36-Gy, six-fraction stereotactic reirradiation (CyberKnife®) for recurrent/secondary H&N cancer between 2007 and 2020 at the Oscar Lambret Center. Patient characteristics and toxicities were assessed. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method.

RESULTS

Median follow-up time was 106.3 months. The 2-year OS rate was 43.8 % (95 % confidence interval, 95 % CI, 34.3-52.9) and the median survival was 20.8 months (95 % CI, 16.5-26.3). The cumulative 2-year local-recurrence, regional-recurrence, and distant-metastasis rates were 52.2 % (95 % CI, 42.4-61.1 %), 12.8 % (95 % CI, 7.4-19.8 %), and 11 % (95 % CI, 6.0-17.6 %), respectively. 73 patients received concomitant cetuximab, and it was not significantly beneficial (HR = 1.34; 95 % CI, 0.80-2.26; p = 0.26). The cumulative incidences of grade ≥ 2 late toxicity was 42 % (CI95%: 33-51) at 24 months. Two grade 4 bleedings and no treatment-related deaths were reported.

CONCLUSION

In a large retrospective series of SBRT reirradiation for recurrent or second primary H&N cancers, we observed a median OS of 20.8 months, with a cumulative incidence of grade ≥ 2 late toxicity of 42 % at 24 months. Such a treatment is feasible. However, local recurrence rates remain non-negligible, warranting further research. Radiosensitizer use is currently under study. Therefore, establishing a balance between therapeutic modifications and toxicity is essential.

Reirradiation of head and neck squamous cell carcinomas: a pragmatic approach-part I: prognostic factors and indications to treatment

INTRODUCTION

Reirradiation (reRT) of locally recurrent/second primary tumors of the head and neck region is a potentially curative treatment for patients not candidate to salvage surgery. Aim of the present study is to summarize available literature on both prognostic factors and indications to curative reRT in this clinical setting.

MATERIALS AND METHODS

A narrative review of the literature was performed on two topics: (1) patients' selection according to prognostic factors and (2) dosimetric feasibility of reRT. Postoperative reRT and palliative intent treatments were out of the scope of this work.

RESULTS

Patient-tumor and treatment-related prognostic factors were analyzed, together with dosimetric parameters concerning target volume and organs at risk. Based on available evidence, a stepwise approach has been proposed aiming to provide a useful tool to identify suitable candidates for curative reRT in clinical practice. This was then applied to two clinical cases, proposed at the end of this work.

CONCLUSION

A second course of RT in head and neck recurrence/second primary tumors is a personalized approach that can be offered to selected patients only in centers with expertise and dedicated equipment following a multidisciplinary team discussion.

Recurrent Oropharyngeal Squamous Cell Carcinomas Maintain Anti-tumor Immunity and Multinucleation Levels Following Completion of Radiation

OBJECTIVE

Oropharyngeal squamous cell carcinoma (OPSCC) recurrence is almost universally fatal. Development of effective therapeutic options requires an improved understanding of recurrent OPSCC biology.

METHODS

We analyzed paired primary-recurrent OPSCC from Veterans treated at the Michael E. DeBakey Veterans Affairs Medical Center between 2000 and 2020 who received curative intent radiation-based treatment (with or without chemotherapy). Patient tumors were analyzed using standard immunohistochemistry and automated imaging of infiltrating lymphocytes and multinucleated tumor cells coupled to machine learning algorithms.

RESULTS

Primary and recurrent tumors demonstrated high concordance via p16 and p53 immunohistochemistry, with comparable levels of multinucleation. In contrast, recurrent tumors demonstrated significantly higher levels of CD8+ tumor infiltrating lymphocytes (p<0.05) and higher levels of PD-L1 expression (p<0.05).

CONCLUSION

Exposure to chemo-radiation and recurrence following treatment preserves critical features of intrinsic tumor biology and the tumor immune microenvironment suggesting that novel treatment regimens may be as effective in the salvage setting as in the definitive intent setting.

[Therapy of tumor recurrences or secondary carcinomas in pretreated area is not compatible with the primary therapy in non-previously treated tissue - an overview]

There are different initial situations in the treatment of local or locoregional recurrences, secondary carcinomas or residual squamous cell carcinomas of the head and neck region after primary therapy. The majority of patients with locoregional recurrences have had prior treatment consisting of surgery and/or postoperative radiotherapy or radiochemotherapy or primary radiotherapy or radiochemotherapy. In any case, it is a matter of new tumor growth in a previously treated area, which must be taken into account for the therapy decision. The biological backgrounds are diverse and are described in more detail and clinically classified in the present work.

Targeting M-MDSCs enhances the therapeutic effect of BNCT in the 4-NQO-induced murine head and neck squamous cell carcinoma model

Purpose

Malignant head and neck squamous cell carcinoma (HNSCC) is characterized by a poor prognosis and resistance to conventional radiotherapy. Infiltrating myeloid-derived suppressive cells (MDSCs) is prominent in HNSCC and is linked to immune suppression and tumor aggressiveness. This study aimed to investigate the impact of boron neutron capture therapy (BNCT) on the MDSCs in the tumor microenvironment and peripheral blood and to explore the potential for MDSCs depletion combined with BNCT to reactivate antitumor immunity.

Methods and materials

Carcinogen, 4-NQO, -induced oral tumors were irradiated with a total physical dose of 2 Gy BNCT in Tsing Hua Open Reactor (THOR). Flow cytometry and immunohistochemistry accessed the dynamics of peripheral MDSCs and infiltrated MDSCs within the tumor microenvironment. Mice were injected with an inhibitor of CSF-1 receptor (CSF-1R), PLX3397, to determine whether modulating M-MDSCs could affect mice survival after BNCT.

Results

Peripheral CD11b+Ly6ChighLy6G- monocytic-MDSCs (M-MDSCs), but not CD11b+Ly6CloLy6Ghigh polymorphonuclear-MDSCs (PMN-MDSCs), increased as tumor progression. After BNCT treatment, there were temporarily decreased and persistent increases of M-MDSCs thereafter, either in peripheral blood or in tumors. The administration of PLX-3397 hindered BNCT-caused M-MDSCs infiltration, prolonged mice survival, and activated tumor immunity by decreasing tumor-associated macrophages (TAMs) and increasing CD8+ T cells.

Conclusion

M-MDSCs were recruited into 4-NQO-induced tumors after BNCT, and their number was also increased in peripheral blood. Assessment of M-MDSCs levels in peripheral blood could be an index to determine the optimal intervention window. Their temporal alteration suggests an association with tumor recurrence after BNCT, making M-MDSCs a potential intervention target. Our preliminary results showed that PLX-3397 had strong M-MDSCs, TAMs, and TIL (tumor-infiltrating lymphocyte) modulating effects that could synergize tumor control when combined with BNCT.

Phase 1 Dose Escalation of Stereotactic Body Radiation Therapy and Concurrent Cisplatin for Reirradiation of Unresectable, Recurrent Squamous Cell Carcinoma of the Head and Neck

PURPOSE

Patients with locoregional recurrence of squamous cell carcinoma of the head and neck (SCCHN) have relatively poor outcomes; therefore, stereotactic body radiation therapy (SBRT) has been investigated for this patient population. We performed a phase 1 clinical trial to establish a maximum tolerated dose of SBRT with concurrent cisplatin in previously irradiated locoregional SCCHN.

METHODS AND MATERIALS

Patients with recurrent SCCHN who had previously undergone radiation therapy to doses ≥45 Gy to the area of recurrence ≥6 months before enrollment and who were not surgical candidates or refused surgery were eligible. SBRT was delivered every other day for 5 fractions. Starting dose level was 6 Gy × 5 fractions, followed by 7 Gy × 5 fractions and 8 Gy × 5 fractions. Chemotherapy consisted of cisplatin given before every SBRT fraction at a dose of 15 mg/m2. Patients were monitored for dose-limiting toxicities (DLT) that occurred within 3 months from the start of SBRT. Secondary endpoints included locoregional failure, distant metastasis, and overall survival.

RESULTS

Twenty patients were enrolled, with 18 patients evaluable for endpoints. One patient at dose level 1 (30 Gy) died of unknown causes 2 weeks following completion of treatment. Therefore, an additional 3 patients were accrued to the 30-Gy dose level, with no further DLTs observed. Three patients were then accrued at dose level 2 (35 Gy) and 9 patients at dose level 3 (40 Gy) without DLTs. At a median follow-up of 9.5 months, cumulative incidence of locoregional failure at 2 years was 61% (95% confidence interval [CI], 12%-66%), cumulative incidence of distant metastasis was 11% (95% CI, 74%-100%) at 2 years, and overall survival was 22% (95% CI, 9%-53%) at 2 years.

CONCLUSIONS

Concurrent cisplatin and reirradiation with an SBRT dose of ≤40 Gy was safe and feasible in patients with locoregionally recurrent or second primary SCCHN.

Predictors of toxicity after curative reirradiation with intensity modulated radiotherapy or proton therapy for recurrent head and neck carcinoma: new dose constraints for pharyngeal constrictors muscles and oral cavity

BACKGROUND

Our study aims to identify predictive factors of moderate to severe (grade ≥ 2) late toxicity after reirradiation (reRT) of recurrent head and neck carcinoma (HNC) and explore the correlations between dose organs at risk (OAR) and grade ≥ 2 toxicity.

MATERIAL AND METHODS

Between 09/2007 and 09/2019, 55 patients were re-irradiated with IMRT or proton therapy with curative intent for advanced HNC. Our study included all patients for whom data from the first and second irradiations were available. Co-variables, including interval to reRT, size of re-irradiated PTV, and dose to OAR, were analyzed as potential predictors for developing moderate to severe long-term toxicity with death as a competing risk. Receiver-operator characteristics (ROC) analysis assessed the association between dose/volume parameters and the risk of toxicity.

RESULTS

Twenty-three patients participated in our study. After a median follow-up of 41 months, 65% of the patients experienced grade ≥ 2 late toxicity. The average dose to pharyngeal constrictor muscles (PCM) at the time of reRT showed an association with the risk of grade ≥ 2 dysphagia: AUC = 0.78 (95% CI: 0.53-1), optimal cut-off value = 36.7 Gy (sensitivity 62%/specificity 100%). The average dose to the oral cavity at the time of reRT showed an association with the risk of grade ≥ 2 dysgeusia: AUC = 0.96 (0.89-1), optimal cut-off value = 20.5 Gy (sensitivity 100%/specificity 88%).

CONCLUSION

Our analysis depicted an association between the dose to OAR and the risk of developing moderate to severe dysphagia and dysgeusia and proposed new dose constraints for PCM (36.7 Gy) and oral cavity (20.5 Gy).

Patterns of recurrence in head and neck squamous cell carcinoma to inform personalized surveillance protocols

BACKGROUND

Development of evidence-based post-treatment surveillance guidelines in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) is limited by comprehensive documentation of patterns of recurrence and metastatic spread.

METHODS

A retrospective analysis of patients diagnosed with R/M HNSCC at a National Cancer Institute-designated cancer center between 1998- 2019 was performed (n = 447). Univariate and multivariate analysis identified patterns of recurrence and predictors of survival.

RESULTS

Median overall survival (mOS) improved over time (6.7 months in 1998-2007 to 11.8 months in 2008-2019, p = .006). Predictors of worse mOS included human papillomavirus (HPV) negativity (hazard ratio [HR], 1.8; 95% confidence interval [CI], 1.2-2.6), high neutrophil/lymphocyte ratio (HR, 2.1 [1.4-3.0], disease-free interval (DFI) ≤6 months (HR, 1.4 [1.02-2.0]), and poor performance status (Eastern Cooperative Oncology Group, ≥2; HR, 1.91.1-3.4). In this cohort, 50.6% of recurrences occurred within 6 months of treatment completion, 72.5% occurred within 1 year, and 88.6% occurred within 2 years. Metachronous distant metastases were more likely to occur in patients with HPV-positive disease (odds ratio [OR], 2.3 [1.4-4.0]), DFI >6 months (OR, 2.4 [1.5-4.0]), and body mass index ≥30 (OR, 2.3 [1.1-4.8]). Oligometastatic disease treated with local ablative therapy was associated with improved survival over polymetastatic disease (HR, 0.36; 95% CI, 0.24-0.55).

CONCLUSION

These data regarding patterns of distant metastasis in HNSCC support the clinical utility of early detection of recurrence. Patterns of recurrence in this population can be used to inform individualized surveillance programs as well as to risk-stratify eligible patients for clinical trials.

PLAIN LANGUAGE SUMMARY

After treatment for head and neck cancer (HNC), patients are at risk of recurrence at prior sites of disease or at distant sites in the body. This study includes a large group of patients with recurrent or metastatic HNC and examines factors associated with survival outcomes and recurrence patterns. Patients with human papillomavirus (HPV)-positive HNC have good survival outcomes, but if they recur, this may be in distant regions of the body and may occur later than HPV-negative patients. These data argue for personalized follow-up schedules for patients with HNC, perhaps incorporating imaging studies or novel blood tests.

An Overview of Head and Neck Tumor Reirradiation: What Has Been Achieved So Far?

The recurrence rate of head and neck cancers (HNCs) after initial treatment may reach 70%, and poor prognosis is reported in most cases. Curative options for recurrent HNCs mainly depend on the treatment history and the recurrent tumor localization. Reirradiation for HNCs is effective and has been included in most guidelines. However, the option remains clinically challenging due to high incidence of severe toxicity, especially in cases of quick infield recurrence. Recent technical advances in radiation therapy (RT) provide the means for upgrade in reirradiation protocols. While the majority of hospitals stay focused on conventional and widely accessible modulated RTs, the particle therapy options emerge as tolerable and providing further treatment opportunities for recurrent HNCs. Still, the progress is impeded by high heterogeneity of the data and the lack of large-scale prospective studies. This review aimed to summarize the outcomes of reirradiation for HNCs in the clinical perspective.

Impact of hyperfractionated re-irradiation on quality of life in patients with recurrent or second primary head and neck cancer, a prospective single institutional study

Purpose

Describe the clinical outcome of hyperfractionated re-irradiation (HFRT) in patients with recurrent or second primary (SP) head and neck cancer (HNC).

Methods

This prospective observational study included HNC patients eligible for HFRT. Inclusion criteria: age ≥18 years, recurrent or SP HNC, planned re-irradiation and ability to respond to questionnaires. Patients received 1.5 Gy twice daily, five days a week for three (palliative) or four (curative/local control) weeks, total dose 45/60 Gy. Toxicity was scored with CTCAE v3 at baseline, end of treatment, at three, six, 12 and 36 months follow-up. Health-related quality of life (HRQoL) was measured with EORTC QLQ-C30 and EORTC QLQ-H&N35, pre-treatment and eight times until 36 months. In the main outcome (Global quality of life and H&N Pain), a change score of ≥10 was considered clinically significant, and p-values < 0.05 (two-sided) statistically significant. The Kaplan-Meier method was used for survival analyses.

Results

Over four years from 2015, 58 patients were enrolled (37 recurrent and 21 SP). All, but two patients completed treatment as planned. Toxicity (≥grade 3) increased from pre-treatment to end of treatment with improvement in the follow-up period. The mean Global quality of life (QoL) and H&N Pain scores were stable from pre-treatment to three months. Maintained/ improved Global QoL was reported by 60% of patients at three months and 56% of patients at 12 months. For patients with curative, local control and palliative intent, the median survival (range) was 23 (2-53), 10 (1-66) and 14 (3-41) months respectively. Of those alive, the proportion of disease-free patients at 12 and 36 months, were 58% and 48%, respectively.

Conclusion

Most HNC patients reported maintained HRQoL at three and 12 months after HFRT despite serious toxicity observed in many patients. Long-term survival can be achieved in a limited proportion of the patients.

Curative high-dose reirradiation for patients with recurrent head and neck adenoid cystic carcinomas: outcomes and analysis of patterns of failure

BACKGROUND

To investigate the outcomes of patients who underwent curative reirradiation (reRT), with intensity-modulated radiation therapy (IMRT) or proton therapy (PT) for unresectable recurrent or second primary head and neck adenoid cystic carcinoma (HNACC).

METHODS

Ten patients, mostly KPS 90%, were reirradiated (3/10 with IMRT and 7/10 with PT) at a median maximum dose to the CTV of 64.2 Gy from July 2011 to November 2021. Locations at the time of reRT were mainly the sinus (4/10) and the salivary glands (including the parotid and submandibular gland, 3/10). CTCAEv5 was used to assess acute and late toxicities. Follow-up was the time between the end of reRT and the date of last news.

RESULTS

The median time between the two irradiations was 53.5 months (IQR: 18-84). After a median follow-up of 26 months (range, 12.5-51.8 months), six patients had developed a locoregional recurrence (LR), of which four occurred within the previously irradiated volume. Two and three-year locoregional failure-free survival (LFFS) and overall survival (OS) were 55.6% [95%CI: 31-99.7%], and 41% [18.5-94%] and 66.7% [42-100%] and 44.4% [21.4-92.3%], respectively. LFFS and OS were significantly better in the subgroup of sinus tumors (p = .013) and the subgroup of patients re-irradiated more than two years after the first course of irradiation (p = .01). Seven patients had impairments before the start of reRT, including hearing impairment (3/10) and facial nerve impairment (3/10). The most severe late toxicities were brain necrosis (2/10), osteoradionecrosis (1/10) and vision decreased (1/10).

CONCLUSION

Curative reRT for HNACC is possible for selected cases, but the LR rate in the irradiated field and the risk of severe toxicity remain high. Improved selection criteria and more carefully defined target volumes may improve outcome in these patients. A further study including larger cohort of patients would be useful to confirm these results.

Recurrent oropharyngeal squamous cell carcinomas maintain anti-tumor immunity and multinucleation levels following completion of radiation

Objective

Oropharyngeal squamous cell carcinoma (OPSCC) recurrence is almost universally fatal. Development of effective therapeutic options requires an improved understanding of recurrent OPSCC biology.

Methods

We analyzed paired primary-recurrent OPSCC from Veterans treated at the Michael E. DeBakey Veterans Affairs Medical Center between 2000 and 2020 who received curative intent radiation-based treatment (with or without chemotherapy). Patient tumors were analyzed using standard immunohistochemistry and automated imaging of infiltrating lymphocytes and multinucleated tumor cells coupled to machine learning algorithms.

Results

Primary and recurrent tumors demonstrated high concordance via p16 and p53 immunohistochemistry, with comparable levels of multinucleation. In contrast, recurrent tumors demonstrated significantly higher levels of CD8+ tumor infiltrating lymphocytes (p<0.05) and higher levels of PD-L1 expression (p<0.05).

Conclusion

Exposure to chemo-radiation and recurrence following treatment does not appear deleterious to underlying biological characteristics and anti-tumor immunity of oropharyngeal cancer, suggesting that novel treatment regimens may be as effective in the salvage setting as in the definitive intent setting.

Dosimetric and clinical aspects of head and neck cancer reirradiation with intensity modulated radiotherapy techniques over the last decade

PURPOSE

Tumor recurrence in head and neck cancer (HNC) is very common, given that locoregional disease relapse occurs in up to 50% of patients. The clinical approach towards cancer recurrence is either by surgery and/or chemo-radiotherapy. Irrespective of the treatment, the management of HNC recurrence is highly challenging and often administered with palliative intent only. The aim of this work was to analyze clinical and dosimetric aspects, such as dose prescription, organ at risk sparing, overall survival and locoregional control of HNC after reirradiation with intensity modulated radiotherapy techniques based on studies published over the last decade, due to the wide clinical implementation of the intensity modulated radiotherapy and particularly of volumetric modulated arc therapy (VMAT) for this malignancy.

METHODS

A systematic search of the literature was conducted within Pub-med/Medline databases to find relevant studies. Of the 130 articles fulfilling the initial search criteria, 15 were selected for final analysis that encompassed all set requirements.

RESULTS

Clinical studies revealed the multitude of factors influencing treatment outcome, including anatomical location, histological tumor type, patient-related factors (smoking / comorbidities), cumulative dose and fractionation schedule, reirradiated volume and time between the irradiation of primary and recurrent tumor.

CONCLUSIONS

Since the literature reports no specific data related to the type of intensity modulation used in reirradiation or any correlation with treatment outcome, IMRT and VMAT might offer comparable result after HNC reirradiation. Patient selection is potentially the main factor leading to an efficient outcome.

Proton Bragg Peak FLASH Enables Organ Sparing and Ultra-High Dose-Rate Delivery: Proof of Principle in Recurrent Head and Neck Cancer

Proton pencil-beam scanning (PBS) Bragg peak FLASH combines ultra-high dose rate delivery and organ-at-risk (OAR) sparing. This proof-of-principle study compared dosimetry and dose rate coverage between PBS Bragg peak FLASH and PBS transmission FLASH in head and neck reirradiation. PBS Bragg peak FLASH plans were created via the highest beam single energy, range shifter, and range compensator, and were compared to PBS transmission FLASH plans for 6 GyE/fraction and 10 GyE/fraction in eight recurrent head and neck patients originally treated with quad shot reirradiation (14.8/3.7 CGE). The 6 GyE/fraction and 10 GyE/fraction plans were also created using conventional-rate intensity-modulated proton therapy techniques. PBS Bragg peak FLASH, PBS transmission FLASH, and conventional plans were compared for OAR sparing, FLASH dose rate coverage, and target coverage. All FLASH OAR V40 Gy/s dose rate coverage was 90-100% at 6 GyE and 10 GyE for both FLASH modalities. PBS Bragg peak FLASH generated dose volume histograms (DVHs) like those of conventional therapy and demonstrated improved OAR dose sparing over PBS transmission FLASH. All the modalities had similar CTV coverage. PBS Bragg peak FLASH can deliver conformal, ultra-high dose rate FLASH with a two-millisecond delivery of the minimum MU per spot. PBS Bragg peak FLASH demonstrated similar dose rate coverage to PBS transmission FLASH with improved OAR dose-sparing, which was more pronounced in the 10 GyE/fraction than in the 6 GyE/fraction. This feasibility study generates hypotheses for the benefits of FLASH in head and neck reirradiation and developing biological models.

Lessons and Opportunities for Biomarker-Driven Radiation Personalization in Head and Neck Cancer

Head and neck cancer is notoriously challenging to treat in part because it constitutes an anatomically and biologically diverse group of cancers with heterogeneous prognoses. While treatment can be associated with significant late toxicities, recurrence is often difficult to salvage with poor survival rates and functional morbidity.^1,2 Thus, achieving tumor control and cure at the initial diagnosis is the highest priority. Given the differing outcome expectations (even within a specific sub-site like oropharyngeal carcinoma), there has been growing interest in personalizing treatment: de-escalation in selected cancers to decrease the risk of late toxicity without compromising oncologic outcomes, and intensification for more aggressive cancers to improve oncologic outcomes without causing undue toxicity. This risk stratification is increasingly accomplished using biomarkers, which can represent molecular, clinicopathologic, and/or radiologic data. In this review, we will focus on biomarker-driven radiotherapy dose personalization with emphasis on oropharyngeal and nasopharyngeal carcinoma. This radiation personalization is largely performed on the population level by identifying patients with good prognosis via traditional clinicopathologic factors, although there are emerging studies supporting inter-tumor and intra-tumor level personalization via imaging and molecular biomarkers.

Repeat re-irradiation with interstitial HDR-brachytherapy for an in-field isolated nodal recurrence in a patient with HPV-positive squamous cell carcinoma of the head and neck

PURPOSE

Locoregionally recurrent head and neck cancer is a complex clinical scenario that often requires multimodality treatment. These patients have often previously received definitive treatment with a combination of surgery, radiation therapy, and systemic therapy, which can make further management difficult. A second isolated locoregional failure is rare and clinicians are faced with a challenge to optimize disease control while minimizing treatment-related toxicity.

METHODS AND MATERIALS

In this report, we present the diagnosis, management, and outcomes of a patient with an isolated locoregional recurrence who was previously treated with two courses of radiation. The patient was treated with a second course of reirradiation using interstitial brachytherapy as well as a discussion regarding patient selection and optimal management for recurrent head and neck cancer.

RESULTS

Repeat reirradiation using interstitial HDR-brachytherapy with the use of an alloderm spacer was successfully delivered to the patient for an in-field right neck nodal recurrence. He received a total EQD2/BED dose of 127.70/153.24 Gy. At 1-year followup, the patient was without evidence of recurrent disease or new significant side effects.

CONCLUSION

Recurrent head and neck cancer should be managed with a multidisciplinary approach given the complex clinical scenario. Reirradiation is a commonly used salvage measure for recurrent head and neck cancer that requires careful planning and patient selection due to prior treatment-related effects and dose constraints. We reported a case of a second course of reirradiation using interstitial HDR-brachytherapy for locoregionally recurrent head and neck cancer and showed no recurrence of disease or worsening long term side effects at 1 year.

Re-irradiation for head and neck cancer: outcome and toxicity analysis using a prospective single institution database

Purpose

Re-irradiation (re-RT) in head and neck cancer is challenging. This study prospectively explored the feasibility of re-RT in patients with loco-regionally recurrent or second primary head and neck cancer (LRR/SP HNC).

Methods

From 2004 to 2021, 61 LRR/SP HNC patients were treated with re-RT, defined as having a second course of RT with curative intent resulting in a cumulative dose of ≥100 Gy in an overlapping volume. Postoperative or definitive dynamic intensity-modulated and/or volumetric modulated re-RT was administered using twice daily hyperfractionation to 60 Gy combined with cisplatin or carboplatin/5-fluorouracil. Overall survival (OS), progression-free survival (PFS), locoregional control (LRC) and distant metastasis control (DMC) were analyzed and prognostic factors evaluated. Toxicity was prospectively recorded and graded.

Results

The median follow-up was 9.8 months. In 41 patients (67.1%), complete administration of the intended treatment was not feasible. In 9 patients (15%) re-RT was interrupted prematurely and in other 9, the complete re-RT dose was lower than 60 Gy, and 37 patients (61%) could not receive or complete chemotherapy. Two-year OS, PFS and LRC rates were 19%, 18% and 30%, respectively. 20 patients (33%) received the complete intended treatment, and 1- and 2-year OS rates were 70% and 47%, respectively. Charlson comorbidity index was an important predictor for treatment completion. Multivariate analysis revealed recurrent N stage 0-1, age, chemotherapy administration and re-RT dose of 60 Gy as prognostic factors for clinical outcomes. No grade 5 re-RT-related toxicity was observed. The most common new grade ≥3 acute toxicities were dysphagia (52%) and mucositis (46%). Late toxicity included grade ≥3 dysphagia in 5% and osteoradionecrosis in 10% of evaluable patients, respectively. 6 patients (10%) were alive after 9 years without progression and no late toxicity grade ≥3, except for 2 patients presenting with osteoradionecrosis.

Conclusion

Hyperfractionated re-RT with 60 Gy combined with platinum-based chemotherapy was a curative treatment option with acceptable toxicity in LRR/SP patients. Patients with higher comorbidity had a higher probability of failing to receive and complete the intended therapy. Consequently, they derived unsatisfactory benefits from re-RT, highlighting the importance of patient selection.

Re-Irradiation for Recurrent Head and Neck Cancer: Freedom from Cancer Recurrence Rate

Salvage re-irradiation (rRT) for patients with locoregionally recurrent head and neck cancer (rHNC) remains challenging. A retrospective analysis was performed on 49 patients who received rRT between 2011 and 2018. The co-primary endpoint of the study was 2-year freedom from cancer recurrence rate (FCRR) and overall survival (OS), and secondary endpoints were 2-year disease-free survival (DFS), local failure (LF), regional failure (RF), distant metastases (DM), and RTOG grade 3 ≥ late toxicities. Adjuvant and definitive rRT were delivered to 22 and 27 patients, respectively. A total of 91% of patients were managed with conventional re-RT and 71% of patients received concurrent chemotherapy. The median follow-up after rRT was 30 months. The 2-year FCRR, OS, DFS, LF, RF, and DM were 64%, 51%, 28%, 32%, 9%, and 39% respectively. MVA showed that poor performance status (PS: 1-2 vs. 0) and age > 52 years were predictive of worse OS. In comparison, poor PS (1-2 vs. 0) and total dose of rRT < 60 Gy were predictive of worse DFS. Late RTOG toxicity of grade 3 ≥ was reported in nine (18.3%) patients. FCRR at 2 years after salvage rRT for rHNC was higher than other traditional endpoints and could be an important endpoint to be included in future rRT studies. rRT for rHNC at our cohort was relatively successful, with a manageable level of late severe toxicity. Replacing this approach in other developing countries is a viable option.

Dose-escalated re-irradiation improves outcome in locally recurrent head and neck cancer - Results of a large multicenter analysis

To determine efficacy and prognostic parameters of definitive re-irradiation of locoregionally recurrent squamous cell carcinoma of the head and neck (HNSCC).

MATERIALS AND METHODS

Patients with locoregionally recurrent or second primary HNSCC undergoing re-irradiation with modern radiotherapy technique were eligible for this multicentric retrospective analysis. Main endpoints were overall survival (OS), progression-free survival (PFS) and locoregional control (LC). Univariate analyses were performed using the Kaplan Meier Method (log-rank). For multivariable analysis, Cox regression was used.

RESULTS

A total of 253 patients treated between 2009 and 2020 at 16 university hospitals in Germany were included. The median follow up was 27.4 months (range 0.5-130). The median OS and PFS were 13.2 (CI: 10.7 - 15.7) months and 7.9 (CI: 6.7 - 9.1) months, respectively, corresponding to two-year OS and PFS rates of 29 % and 19 %. Rates of locoregional progression and "in-field-failure" were 62 % and 51 % after two years. Multivariable Cox regression analysis identified good ECOG performance status and high radiation dose as independent prognostic parameters for OS. Doses above 50 Gy (EQD2) achieved longer median OS of 17.8 months (vs 11.7 months, p < 0.01) and longer PFS of 9.6 months (vs 6.8 months, p < 0.01). In addition, there was a trend for worse survival in patients with tracheostomy (multivariable, p = 0.061). Concomitant systemic therapy did not significantly impact PFS or OS.

CONCLUSION

Re-irradiation of locally recurrent or second primary HNSCC is efficient, especially if doses above 50 Gy (EQD2) are delivered. ECOG performance score was the strongest prognostic parameter for OS and PFS.

Adjuvant PD-1 Antibody in Recurrent, Previously Irradiated Oral Cavity Cancer Treated with Salvage Surgery

Objectives

The role of re-irradiation after salvage surgery for recurrent oral cavity cancer (OCC) is controversial. We evaluated the efficacy and safety of adjuvant toripalimab (PD-1 antibody) in this patient setting.

Materials and methods

In this phase II study, patients after salvage surgery with OCC occurring in an area of previously irradiated were enrolled. Patients received toripalimab 240 mg once every 3 weeks for 12 months, or combined with S-1 orally for 4-6 cycles. The primary endpoint was 1-year progression-free survival (PFS).

Results

Between April 2019 and May 2021, 20 patients were enrolled. Sixty percent patients had ENE or positive margins, 80% were restaged as stage IV, and 80% were previously treated with chemotherapy. The 1-year PFS and overall survival (OS) were 58.2%, and 93.8%, respectively, for patients with CPS ≥ 1, which was significantly better than those of the real-world reference cohort (p = 0.001 and 0.019). No grade 4-5 toxicities were reported, and only one patient experienced grade 3 immune related adrenal insufficiency and discontinued treatment. The 1-year PFS and OS were significantly different for patients with CPS < 1, CPS 1-19 and CPS ≥ 20 (p = 0.011 and 0.017, respectively). The peripheral blood B cell proportion was also correlated with PD in 6 months (p = 0.044).

Conclusion

Adjuvant toripalimab or combine with S-1 after salvage surgery showed improved PFS compared with a real-world reference cohort in recurrent, previously irradiated OCC, and favorable PFS were observed in patients with a higher CPS and peripheral B cell proportion. Further randomized trials are warranted.

Reirradiation for local recurrence of oral, pharyngeal, and laryngeal cancers: a multi-institutional study

This study aimed to examine the efficacy and toxicity of reirradiation in patients with locally recurrent oral, pharyngeal, and laryngeal cancers. We conducted a retrospective, multi-institutional analysis of 129 patients with previously irradiated cancer. The most frequent primary sites were the nasopharynx (43.4%), oral cavity (24.8%), and oropharynx (18.6%). With a median follow-up duration of 10.6 months, the median overall survival was 14.4 months and the 2-year overall survival rate was 40.6%. For each primary site, the 2-year overall survival rates were 32.1%, 34.6%, 30%, 60.8%, and 5.7% for the hypopharynx, oral cavity, larynx, nasopharynx, and oropharynx, respectively. Prognostic factors for overall survival were primary site (nasopharynx versus other sites) and gross tumor volume (GTV) (≤ 25 cm³ versus > 25 cm³). The 2-year local control rate was 41.2%. Twenty-four patients (18.6%) presented with grade ≥ 3 toxicities, including nine with hemorrhages that led to grade 5 toxicities in seven patients. All nine tumors that caused hemorrhage showed tumor encasement of the carotid ≥ 180 degrees and eight of nine tumors had larger GTV > 25 cm³. Reirradiation is a feasible treatment option for small local recurrence of oral, pharyngeal, and laryngeal cancers, with the requirement of a strict eligibility assessment for large tumors with carotid encasement.

Quality of Life in Patients With Recurrent and Second Primary Head and Neck Cancer

OBJECTIVE

In the setting of similar outcomes, quality of life (QOL) measures can be utilized to compare treatment modalities in head and neck squamous cell carcinoma (HNSCC). We evaluate QOL and symptoms in patients treated for primary, second primary, and recurrent HNSCC.

STUDY DESIGN

Retrospective cohort study.

SETTING

Head and neck cancer survivorship clinic.

METHODS

We identified patients seen between 2016 and 2019. QOL and symptoms were assessed with the University of Washington Quality of Life (UW-QOL) questionnaire, 10-item Eating Assessment Tool, 8-item Patient Health Questionnaire, 7-item Generalized Anxiety Disorder, and Neck Disability Index. Regression analysis was utilized to explore associations and compare QOL outcomes.

RESULTS

Our cohort comprised 662 patients: 546 with primary HNSCC, 34 with second primary HNSCC, and 82 with recurrent HNSCC. Multimodality therapy was associated with lower UW-QOL Physical Subscale (UW-QOL-PS) vs single modality: chemoradiation therapy (-12.17 [95% CI, -16.57 to -7.78]) and surgery + postadjuvant treatment (-12.11 [-16.06 to -8.16]). Multimodality therapy was also associated with lower UW-QOL Social-Emotional Subscale (UW-QOL-SS): chemoradiation therapy (-6.70 [-11.41 to -1.99]) and surgery + postadjuvant treatment (-7.41 [-11.63 to -3.19]). Recurrence (-14.42 [-18.80 to -10.04]) and second primary (-11.15 [-17.71 to -4.59]) demonstrated lower UW-QOL-PS vs primary. Radiation for recurrence or second primary had worse UW-QOL-PS (-10.43 [-19.27 to -1.59]) and UW-QOL-SS (-10.58 [-18.76 to -1.54]) and higher Eating Assessment Tool (6.08 [1.39-10.77]) than surgery alone. Surgery + postadjuvant treatment showed worse UW-QOL-PS (-12.65 [-23.76 to -1.54]) and UW-QOL-SS (-12.20 [-22.38 to -2.03]).

CONCLUSION

Multimodality therapy, particularly with recurrent and second primary HNSCC, is more likely to contribute to diminished QOL and symptoms. This important consideration should play a role in framing informed discussions with patients regarding treatment.

Combined Hyperthermia and Re-Irradiation in Non-Breast Cancer Patients: A Systematic Review

PURPOSE

This systematic literature review summarizes clinical studies and trials involving combined non-ablative hyperthermia and re-irradiation in locoregionally recurrent cancer except breast cancer.

METHODS

One database and one registry, MEDLINE and clinicaltrials.gov, respectively, were searched for studies on combined non-ablative hyperthermia and re-irradiation in non-breast cancer patients. Extracted study characteristics included treatment modalities and re-irradiation dose concepts. Outcomes of interest were tumor response, survival measures, toxicity data and palliation. Within-study bias assessment included the identification of conflict of interest (COI). The final search was performed on 29 August 2022.

RESULTS

Twenty-three articles were included in the final analysis, reporting on 603 patients with eight major tumor types. Twelve articles (52%) were retrospective studies. Only one randomized trial was identified. No COI statement was declared in 11 studies. Four of the remaining twelve studies exhibited significant COI. Low study and patient numbers, high heterogeneity in treatment modalities and endpoints, as well as significant within- and across-study bias impeded the synthesis of results.

CONCLUSION

Outside of locoregionally recurrent breast cancer, the role of combined moderate hyperthermia and re-irradiation can so far not be established. This review underscores the necessity for more clinical trials to generate higher levels of clinical evidence for combined re-irradiation and hyperthermia.

Evaluation of Proton Therapy Reirradiation for Patients With Recurrent Head and Neck Squamous Cell Carcinoma

Importance

Use of proton therapy reirradiation (PT-ReRT) for head and neck cancer is increasing; however, reports are heterogenous and outcomes can be difficult to interpret.

Objective

To evaluate outcomes and toxic effects following PT-ReRT in a uniform and consecutive cohort of patients with head and neck squamous cell carcinoma.

Design, Setting, and Participants

This retrospective cohort study included patients with recurrent primary head and neck squamous cell carcinoma who were treated with PT-ReRT from January 1, 2013, to December 31, 2020, at a single institution. Patient, clinical, and treatment characteristics were obtained, and multidisciplinary review was performed to record and grade early and late toxic effects.

Exposures

Proton therapy reirradiation.

Main Outcomes and Measures

Follow-up was defined from the start of PT-ReRT. The Kaplan-Meier method was used for outcomes of interest, including local control (LC), locoregional control, distant metastatic control, progression-free survival, and overall survival (OS). Cox proportional hazards regression modeling was used to assess associations of covariates with OS.

Results

A total of 242 patients (median [range] age, 63 [21-96] years; 183 [75.6%] male) were included. Of these patients, 231 (95.9%) had a Karnofsky performance status score of 70 or higher, and 145 (59.9%) had at least a 10-pack-year smoking history. Median (range) follow-up was 12.0 (5.8-26.0) months for all patients and 24.5 (13.8-37.8) months for living patients. A total of 206 patients (85.1%) had recurrent disease vs second primary or residual disease. The median (range) interval between radiation courses was 22 (1-669) months. Median PT-ReRT dose was 70 cobalt gray equivalents (CGE) for the fractionated cohort and 44.4 CGE for the quad shot cohort. For the fractionated cohort, the 1-year LC was 71.8% (95% CI, 62.8%-79.0%) and the 1-year OS was 66.6% (95% CI, 58.1%-73.8%). For the quad shot cohort, the 1-year LC was 61.6% (95% CI, 46.4%-73.6%) and the 1-year OS was 28.5% (95% CI, 19.4%-38.3%). Higher Karnofsky performance status scores (hazard ratio [HR], 0.50; 95% CI, 0.25-0.99; P = .046) and receipt of salvage surgery prior to PT-ReRT (HR, 0.57; 95% CI, 0.39-0.84; P = .005) were associated with improved OS, whereas receipt of quad shot (HR, 1.97; 95% CI, 1.36-2.86; P < .001) was associated with worse OS. There were a total of 73 grade 3 and 6 grade 4 early toxic effects. There were 79 potential grade 3, 4 grade 4, and 5 grade 5 late toxic effects.

Conclusions and Relevance

The findings of this cohort study suggest that, compared with previous reports with photon-based reirradiation, patients are living longer with aggressive PT-ReRT; however, surviving patients remain at risk of early and late complications.

[18F]-FDG PET and MRI radiomic signatures to predict the risk and the location of tumor recurrence after re-irradiation in head and neck cancer

PURPOSE

To evaluate whether radiomics from [18F]-FDG PET and/or MRI before re-irradiation (reRT) of recurrent head and neck cancer (HNC) could predict the occurrence and the location "in-field" or "outside" of a second locoregional recurrence (LR).

METHODS

Among the 55 patients re-irradiated at curative intend for HNC from 2012 to 2019, 48 had an MRI and/or PET before the start of the reRT. Thirty-nine radiomic features (RF) were extracted from the re-irradiated GTV (rGTV) using LIFEx software. Student t tests and Spearman correlation coefficient were used to select the RF that best separate patients who recurred from those who did not, and "in-field" from "outside" recurrences. Principal component analysis involving these features only was used to create a prediction model. Leave-one-out cross-validation was performed to evaluate the models.

RESULTS

After a median follow-up of 17 months, 40/55 patients had developed a second LR, including 18 "in-field" and 22 "outside" recurrences. From pre-reRT MRI, a model based on three RF (GLSZM_SZHGLE, GLSZM_LGLZE, and skewness) predicted whether patients would recur with a balanced accuracy (BA) of 83.5%. Another model from pre-reRT MRI based on three other RF (GLSZM_ LZHGE, NGLDM_Busyness, and GLZLM_SZE) predicted whether patients would recur "in-field" or "outside" with a BA of 78.5%. From pre-reRT PET, a model based on four RF (Kurtosis, SUVbwmin, GLCM_Correlation, and GLCM_Contrast) predicted the LR location with a BA of 84.5%.

CONCLUSION

RF characterizing tumor heterogeneity extracted from pre-reRT PET and MRI predicted whether patients would recur, and whether they would recur "in-field" or "outside".

Phase I study of nab-paclitaxel-based induction followed by nab-paclitaxel-based concurrent chemotherapy and re-irradiation in previously treated head and neck squamous cell carcinoma

BACKGROUND

Recurrent head and neck squamous cell carcinoma (HNSCC) is associated with poor overall survival (OS). Prior studies suggested incorporation of nab-paclitaxel (A) may improve outcomes in recurrent HNSCC.

METHODS

This Phase I study evaluated induction with carboplatin and A followed by concomitant FHX (infusional 5-fluorouracil, hydroxyurea and twice-daily radiation therapy administered every other week) plus A with cohort dose escalation ranging from 10-100 mg/m2 in recurrent HNSCC. The primary endpoint was maximally tolerated dose (MTD) and dose-limiting toxicity (DLT) of A when given in combination with FHX (AFHX).

RESULTS

Forty-eight eligible pts started induction; 28 pts started AFHX and were evaluable for toxicity. Two DLTs occurred (both Grade 4 mucositis) at a dose level 20 mg/m2. No further DLTs were observed with subsequent dose escalation. The MTD and recommended Phase II dose (RP2D) of A was 100 mg/m2.

CONCLUSIONS

In this Phase I study, the RP2D of A with FHX is 100 mg/m2 (AFHX). The role of re-irradiation with immunotherapy warrants further investigation.

CLINICAL TRIAL INFORMATION

This clinical trial was registered with ClinicalTrials.gov identifier: NCT01847326.

Transoral Robotic Surgery for Recurrent Tumors of the Upper Aerodigestive Tract (RECUT): An International Cohort Study

BACKGROUND

Transoral robotic surgery (TORS) is an emerging minimally invasive surgical treatment for residual, recurrent, and new primary head and neck cancers in previously irradiated fields, with limited evidence for its oncological effectiveness.

METHODS

A retrospective observational cohort study of consecutive cases performed in 16 high-volume international centers before August 2018 was conducted (registered at clinicaltrials.gov [NCT04673929] as the RECUT study). Overall survival (OS), disease-free survival, disease-specific survivals (DSS), and local control (LC) were calculated using Kaplan-Meier estimates, with subgroups compared using log-rank tests and Cox proportional hazards modeling for multivariable analysis. Maximally selected rank statistics determined the cut point for closest surgical resection margin based on LC.

RESULTS

Data for 278 eligible patients were analyzed, with median follow-up of 38.5 months. Two-year and 5-year outcomes were 69.0% and 62.2% for LC, 71.8% and 49.8% for OS, 47.2% and 35.7% for disease-free survival, and 78.7% and 59.1% for disease-specific survivals. The most discriminating margin cut point was 1.0 mm; the 2-year LC was 80.9% above and 54.2% below or equal to 1.0 mm. Increasing age, current smoking, primary tumor classification, and narrow surgical margins (≤1.0 mm) were statistically significantly associated with lower OS. Hemorrhage with return to theater was seen in 8.1% (n = 22 of 272), and 30-day mortality was 1.8% (n = 5 of 272). At 1 year, 10.8% (n = 21 of 195) used tracheostomies, 33.8% (n = 66 of 195) used gastrostomies, and 66.3% (n = 53 of 80) had maintained or improved normalcy of diet scores.

CONCLUSIONS

Data from international centers show TORS to treat head and neck cancers in previously irradiated fields yields favorable outcomes for LC and survival. Where feasible, TORS should be considered the preferred surgical treatment in the salvage setting.

Salvage (re) radiation in oligometastatic and oligorecurrent cervical cancer

INTRODUCTION

In patients with recurrent or metastatic cervical cancer, the median survival is 13-24 months based on the choice of palliative systemic chemotherapy. Evolving evidence suggests that the addition of radiation may lead to improved survival.

MATERIAL AND METHODS

Consecutive patients treated with radiation+/- systemic chemotherapy for oligometastatic or oligo-recurrent disease between 2017-2020 were included. All patients received systemic chemotherapy consultation and radiation to relapsed or metastatic sites. Progression-free survival (PFS) was determined as the period between diagnosis of relapse or metastasis and the last progression of the disease. Overall survival was defined as the time between the date of diagnosis of relapse or metastasis and follow-up or death. The impact of various prognostic and predictive factors was estimated using the Kaplan Meier and log-rank method.

RESULTS

Fifty-eight consecutive patients were included. The median time to relapse was 18 months (8-205 months). At the time of first relapse, 34.4% patients (n=20) had locoregional relapse, 32.8% (n=19) patients had distant nodal metastases and 32.8% (n=19) had visceral metastases. The relapse was within previously irradiated portals in 34.5%(n=20), out of field in 50% (n=29), and both in 15.5% (n=9) of patients. Overall, 56%(n=33) of patients received systemic chemotherapy. Radiotherapy dose in equivalent doses of 2 Gy (EQD2Gy) at the time of retreatment was 44 Gy (31- 68 Gy). The median PFS and OS from the date of first relapse were 16 (12-19) and 28 months (2-108). Grade ≥ 3 toxicity was observed in 19% of patients. No patient or treatment-related factor was identified as predictive of OS on univariate analysis.

CONCLUSION

The use of potentially radical doses of radiation, including reirradiation at locoregional or distant oligo-relapse or metastasis, is associated with encouraging PFS and OS in patients with cervical cancer.

Survival and disease progression following solitary locoregional recurrence after head and neck radiotherapy

PURPOSE

The management of solitary locoregional recurrence (sLRR) of head and neck squamous cell carcinoma (HNSCC) previously treated with radiotherapy (RT) is challenging. We aimed to identify characteristics associated with improved outcome.

METHODS

We identified patients treated with non-sinus, mucosal HNSCC who initially received IMRT. We characterized overall survival (OS) and locoregional control (LRC). Multivariable analysis (MVA) on survival and patterns-of-failure were performed using Cox and Fine-Gray competing risks analysis.

RESULTS

We identified 90 patients with available follow-up. In total, 67 (74%) patients received curative-intent salvage, while 23 (26%) received palliative care. On MVA, significantly improved OS and LRC were associated with lower initial N-classification and use of salvage total laryngectomy (TL) or neck dissection (ND).

CONCLUSION

A nontrivial number of patients with sLRR cannot undergo salvage. Among patients treated with curative intent, TL or ND were clearly associated with improved OS and LRC.

Retreatment of Recurrent or Second Primary Head and Neck Cancer After Prior Radiation: Executive Summary of the American Radium Society® (ARS) Appropriate Use Criteria (AUC): Expert Panel on Radiation Oncology - Head and Neck Cancer

BACKGROUND

Re-treatment of recurrent or second primary head and neck cancers occurring in a previously irradiated field is complex. Few guidelines exist to support practice.

METHODS

We performed an updated literature search of peer-reviewed journals in a systematic fashion. Search terms, key questions, and associated clinical case variants were formed by panel consensus. The literature search informed the committee during a blinded vote on the appropriateness of treatment options via the modified Delphi method.

RESULTS

The final number of citations retained for review was 274. These informed five key questions, which focused on patient selection, adjuvant re-irradiation, definitive re-irradiation, stereotactic body radiation (SBRT), and re-irradiation to treat non-squamous cancer. Results of the consensus voting are presented along with discussion of the most current evidence.

CONCLUSIONS

This provides updated evidence-based recommendations and guidelines for the re-treatment of recurrent or second primary cancer of the head and neck.

Multicenter study of re-irradiation using carbon-ions for head and neck malignancies after photon radiotherapy

Purpose

The goal of this multicenter retrospective study of patients with head and neck malignancies was to evaluate the efficacy and safety of carbon‐ion (C‐ion) radiotherapy (RT) after photon RT.

Methods

We enrolled 56 patients with head and neck malignancies who underwent re‐irradiation (re‐RT) using C‐ions between November 2003 and March 2019, treated previously with photon RT. The tumors at re‐RT were located in the sinonasal cavities (n = 20, 35.7%), skull base (n = 12, 21.4%), and orbit (n = 7, 12.5%). The tumors at the initial RT were located in the sinonasal cavities (n = 13, 23.2%), skull base (n = 9, 16.1%), and orbit (n = 9, 16.1%). The median period between the initial RT and re‐RT was 41 (4–568) months. The most common histology of re‐RT was squamous cell carcinoma (n = 11, 19.6%). The most commonly used protocol was 57.6 Gy (relative biological effectiveness) in 16 fractions (n = 23, 41.1%). Surgery preceded re‐RT in three patients (5.4%). One patient with malignant melanoma received concurrent chemotherapy.

Results

The 2‐year local control, progression‐free survival, and overall survival rates were 66.5%, 36.9%, and 67.9%, respectively. The median follow‐up time was 28 months. Two patients (3.6%) developed grade ≥ 3 acute toxicities, and 14 (25.0%) developed grade ≥ 3 late toxicities. A single patient had confirmed grade 5 dermatitis with infection.

Conclusion

Re‐RT using C‐ions for head and neck malignancies after photon RT is an effective treatment with tolerable toxicity.

Outcomes of Primary Mucosal Head and Neck Squamous Cell Carcinoma in Solid Organ Transplant Recipients

Introduction Patients who undergo solid organ transplants have a higher risk of developing malignancies and subsequent recurrences. Clinical outcomes in transplant recipients with primary mucosal head and neck squamous cell carcinoma (HNSCC) are not well described in the published literature. Therefore, we retrospectively studied the outcomes in this group of patients.  Methods This Institutional Review Board (IRB)-approved analysis included patients who had previously undergone solid organ transplants and subsequently were diagnosed with primary mucosal HNSCC between 2006 and 2021. Our institutional database of solid organ transplant recipients was cross-referenced with our head and neck cancer database to identify the patients included in this cohort. In addition, Kaplan-Meier analyses were performed to calculate overall and disease-free survival. Results Of 1,221 patients, 20 met the inclusion criteria. The median time from organ transplant to HNSCC diagnosis was 5.9 years (range: 0.5-18.5 years). A total of 11 (55.0%) and 9 (45.0%) patients presented with localized and locally advanced disease, respectively. Two-year overall and disease-free survivals were 59.1% and 73.5%, respectively. After initial treatment, six (30.0%) patients experienced a recurrence. All patients who developed a recurrence died within the follow-up period. The median time of death after recurrence for all six patients was 11.5 months (range: 2-22 months).  Conclusion This series highlights a high mortality rate following recurrence among patients with primary mucosal HNSCC and a solid organ transplant history. A better understanding of how solid organ transplant history adversely impacts the course of HNSCC could help properly guide treatment, follow-up, and survivorship decisions.

Reirradiation of Recurrent and Second Primary Cancers of the Head and Neck: a Review of the Contemporary Evidence

OPINION STATEMENT

Recurrent and second primary head and neck cancers represent a clinical challenge due to frequently unresectable and/or locally advanced disease. Given that many of these patients have received definitive doses of radiation previously, reirradiation is associated with significant morbidity. Use of modern approaches such as conformal photon-based planning and charged particle therapy using protons or carbon ions allows for greater sparing of normal tissues while maintaining or escalating doses to tumor volumes. While the reirradiation data has consistently shown benefits to local control and even survival from escalation of radiotherapy dose, excessive cumulative doses can result in severe toxicities, including fatal carotid blowout syndrome. For all modalities, appropriate patient selection is of utmost importance. Large-scale trials and multi-institutional registry data are needed to standardize treatment modalities, and to determine optimal doses and volumes for reirradiation.

Neoadjuvant and Adjuvant Nivolumab and Lirilumab in Patients with Recurrent, Resectable Squamous Cell Carcinoma of the Head and Neck

PURPOSE

Surgery often represents the best chance for disease control in locoregionally recurrent squamous cell carcinoma of the head and neck (SCCHN). We investigated dual immune-checkpoint inhibition [anti-PD-1, nivolumab (N), and anti-KIR, lirilumab (L)] before and after salvage surgery to improve disease-free survival (DFS).

PATIENTS AND METHODS

In this phase II study, patients received N (240 mg) + L (240 mg) 7 to 21 days before surgery, followed by six cycles of adjuvant N + L. Primary endpoint was 1-year DFS; secondary endpoints were safety, pre-op radiologic response, and overall survival (OS). Correlatives included tumor sequencing, PD-L1 scoring, and immunoprofiling.

RESULTS

Among 28 patients, the median age was 66, 86% were smokers; primary site: 9 oral cavity, 9 oropharynx, and 10 larynx/hypopharynx; 96% had prior radiation. There were no delays to surgery. Grade 3+ adverse events: 11%. At the time of surgery, 96% had stable disease radiologically, one had progression. Pathologic response to N + L was observed in 43% (12/28): 4/28 (14%) major (tumor viability, TV ≤ 10%) and 8/28 (29%) partial (TV ≤ 50%). PD-L1 combined positive score (CPS) at surgery was similar regardless of pathologic response (P = 0.71). Thirteen (46%) recurred (loco-regional = 10, distant = 3). Five of 28 (18%) had positive margins, 4 later recurred. At median follow-up of 22.8 months, 1-year DFS was 55.2% (95% CI, 34.8-71.7) and 1-year OS was 85.7% (95% CI, 66.3-94.4). Two-year DFS and OS were 64% and 80% among pathologic responders.

CONCLUSIONS

(Neo)adjuvant N + L was well tolerated, with a 43% pathologic response rate. We observed favorable DFS and excellent 2-year OS among high-risk, previously treated patients exhibiting a pathologic response. Further evaluation of this strategy is warranted.See related commentary by Sacco and Cohen, p. 435.

Re-irradiation for recurrent or second primary head and neck cancer

Purpose

To investigate the efficacy and safety of intensity-modulated radiotherapy (IMRT)-based re-irradiation (reRT) for recurrent or second primary head and neck cancer (HNC).

Materials and Methods

Patients who underwent IMRT-based reRT for recurrent or second primary HNC between 2007 and 2019 at two institutions were included. Medical records and dosimetric data were retrospectively reviewed. Overall survival (OS), progression-free survival (PFS), severe late toxicities, and clinicopathological prognostic factors were analyzed.

Results

A total of 42 patients were analyzed. With a median follow-up of 15.1 months (range, 3.7 to 85.8 months), the median OS was 28.9 months with a 2-year OS rate of 54.6%. The median PFS and 2-year PFS rates were 10.0 months and 30.9%, respectively. Multivariate analysis showed that good performance (Eastern Cooperative Oncology Group [ECOG] 0 or 1), a longer time interval (≥24 months) between radiotherapy courses, and higher reRT dose (>60 Gy) were significantly favorable factors for OS (all p < 0.05). Higher reRT dose and salvage surgery were significantly associated with improved PFS (all p < 0.05). Regarding the Multi‐Institution Reirradiation (MIRI) Collaborative RPA classification, the 2-year OS rates of each class were 87.5% in class I, 51.8% in class II, and 0% in class III (p = 0.008). Grade ≥3 late toxicity was reported in 10 (23.8%) patients. There was no significant factor associated with increased late toxicities.

Conclusion

IMRT-based reRT should be considered as a treatment option for patients with recurrent or second primary HNC. Further trials are needed to establish a subset of patients who may benefit from reRT without severe late toxicity.

Management of oropharyngeal squamous cell carcinoma

This article reviews the various treatment options, by primary or postoperative external radiotherapy and by brachytherapy for the p16-negative oropharyngeal squamous cell carcinoma. Dose levels, fractionation and association with systemic treatments are presented. The need for neck node dissection post local treatment is discussed, as well as specificities for the management of p16-positive tumours. Guidelines for target volume selection and delineation are thoroughly elaborated. Last, the management by radiotherapy of locoregional recurrences is discussed.

Feasibility, SAR Distribution, and Clinical Outcome upon Reirradiation and Deep Hyperthermia Using the Hypercollar3D in Head and Neck Cancer Patients

(1) Background: Head and neck cancer (HNC) patients with recurrent or second primary (SP) tumors in previously irradiated areas represent a clinical challenge. Definitive or postoperative reirradiation with or without sensitizing therapy, like chemotherapy, should be considered. As an alternative to chemotherapy, hyperthermia has shown to be a potent sensitizer of radiotherapy in clinical studies in the primary treatment of HNC. At our institution, we developed the Hypercollar3D, as the successor to the Hypercollar, to enable improved application of hyperthermia for deeply located HNC. In this study, we report on the feasibility and clinical outcome of patients treated with the Hypercollar3D as an adjuvant to reirradiation in recurrent or SP HNC patients; (2) Methods: We retrospectively analyzed all patients with a recurrent or SP HNC treated with reirradiation combined with hyperthermia using the Hypercollar3D between 2014 and 2018. Data on patients, tumors, and treatments were collected. Follow-up data on disease specific outcomes as well as acute and late toxicity were collected. Data were analyzed using Kaplan Meier analyses; (3) Results: Twenty-two patients with recurrent or SP HNC were included. The average mean estimated applied cfSAR to the tumor volume for the last 17 patients was 80.5 W/kg. Therefore, the novel Hypercollar3D deposits 55% more energy at the target than our previous Hypercollar applicator. In patients treated with definitive thermoradiotherapy a complete response rate of 81.8% (9/11) was observed at 12 weeks following radiotherapy. Two-year local control (LC) and overall survival (OS) were 36.4% (95% CI 17.4-55.7%) and 54.6% (95% CI 32.1-72.4%), respectively. Patients with an interval longer than 24 months from their previous radiotherapy course had an LC of 66.7% (95% CI 37.5-84.6%), whereas patients with a time interval shorter than 24 months had an LC of 14.3% (95% CI 0.7-46.5%) at 18 months (p = 0.01). Cumulative grade 3 or higher toxicity was 39.2% (95% CI 16.0-61.9%); (4) Conclusions: Reirradiation combined with deep hyperthermia in HNC patients using the novel Hypercollar3D is feasible and deposits an average cfSAR of 80.5 W/kg in the tumor volume. The treatment results in high complete response rates at 12 weeks post-treatment. Local control and local toxicity rates were comparable to those reported for recurrent or SP HNC. To further optimize the hyperthermia treatment in the future, temperature feedback is warranted to apply heat at the maximum tolerable dose without toxicity. These data support further research in hyperthermia as an adjuvant to radiotherapy, both in the recurrent as well as in the primary treatment of HNC patients.

Contemporary radiotherapy: present and future

Oncology care is increasingly a multidisciplinary endeavour, and radiation therapy continues to have a key role across the disease spectrum in nearly every cancer. However, the field of radiation oncology is still one of the most poorly understood of the cancer disciplines. In this Review, we attempt to summarise and contextualise developments within the field of radiation oncology for the non-radiation oncologist. We discuss advancements in treatment technologies and imaging, followed by an overview of the interplay with advancements in systemic therapy and surgical techniques. Finally, we review new frontiers in radiation oncology, including advances within the metastatic disease continuum, reirradiation, and emerging types of radiation therapy.