Photoimmunotherapy for Managing Recurrent Laryngeal Cancer Cervical Lesions: A Case Report

Near-infrared photoimmunotherapy for salivary duct carcinoma

In Japan, near-infrared photoimmunotherapy (NIR-PIT) was introduced in 2021 as a treatment option for unresectable recurrent head and neck cancer. The treatment targets the epidermal growth factor receptor (EGFR), which is overexpressed in 80-90 % of head and neck squamous cell carcinoma (HNSCC). NIR-PIT should theoretically show therapeutic efficacy if EGFR is expressed, even in nonsquamous cell carcinomas (non-SCC). To the best of our knowledge, there are no case reports of NIR-PIT for non-SCC. We performed NIR-PIT in a patient with non-SCC of the head and neck region. After performing two NIR-PIT treatments, small free clusters of residual tumor cells were observed. Immunostaining in this specimen revealed EGFR expression in residual tumor cells. The residual tumor cells had been irradiated sufficiently to achieve necrosis. It is suggested that not only laser irradiation and expression of EGFR but also other factors are involved in the efficacy of this treatment. Further investigation for these other factors is warranted.

Radiation therapy, tissue radiosensitization, and potential synergism in the era of novel antibody-drug conjugates

Antibody-drug conjugates (ADCs) represent a therapeutic class of agents designed to selectively deliver cytotoxic payloads to cancer cells. With the increasingly positioning of ADCs in the clinical practice, combinations with other treatment modalities, including radiation therapy (RT), will open new opportunities but also challenges. This review evaluates ADC-RT interactions, examining therapeutic synergies and potential caveats. ADC payloads can be radiosensitizing, enhancing cytotoxicity when used in combination with RT. Antigens targeted by ADCs can have various tissue expressions, resulting in possible off-target toxicities by tissue radiosensitization. Notably, the HER-2-directed ADC trastuzumab emtansine has appeared to increase the risk of radionecrosis when used concomitantly with brain RT, as glial cells can express HER2, too. Other possible organ-specific effects are discussed, such as pulmonary and cardiac toxicities. The lack of robust clinical data on the ADC-RT combination raises concerns regarding specific side effects and the ultimate trade-off of toxicity and safety of some combined approaches. Clinical studies are needed to assess ADC-RT combination safety and efficacy.

Near-infrared photoimmunotherapy and anti-cancer immunity

The activation of the anti-cancer immune system is an important strategy to control cancer. A new form of cancer phototherapy, near-infrared photoimmunotherapy (NIR-PIT), was approved for clinical use in 2020 and uses IRDye® 700DX (IR700)-conjugated antibodies and NIR light. After irradiation with NIR light, the antibody-IR700 conjugate forms water-insoluble aggregations on the plasma membrane of target cells. This aggregation causes lethal damage to the plasma membrane, and effectively leads to immunogenic cell death (ICD). Subsequently, ICD activates anti-cancer immune cells such as dendritic cells and cytotoxic T cells. Combination therapy with immune-checkpoint blockade has synergistically improved the anti-cancer effects of NIR-PIT. Additionally, NIR-PIT can eliminate immunosuppressive immune cells in light-irradiated tumors by using specific antibodies against regulatory T cells and myeloid-derived suppressor cells. In addition to cancer-cell-targeted NIR-PIT, such immune-cell-targeted NIR-PIT has shown promising results by activating the anti-cancer immune system. Furthermore, NIR-PIT can be used to manipulate the tumor microenvironment by eliminating only targeted cells in the tumor, and thus it also can be used to gain insight into immunity in basic research.

Two Cases of Emergency Tracheostomy After Head and Neck Photoimmunotherapy

Background/Aim

Head and neck photoimmuno-therapy (HN-PIT) has been an insured treatment in Japan for approximately three years. The number of treatments has gradually increased to over 350 cases. However, there are still various questions in actual clinical practice, including laryngeal edema. Therefore, it is vital to carefully explain in advance to patients the possibility of laryngeal edema occurring and obtaining consent for tracheostomy as a prophylactic or emergency measure. At our institution, 44 HN-PIT cycles were performed in 23 patients between January 2021 and October 2023. Of these, we experienced two cases in which preventive tracheostomy was not performed because the risk of laryngeal edema was considered low; however, laryngeal edema developed after treatment, and an emergency tracheostomy had to be performed.

Case Report

Case 1 was a patient in his 70s with a local recurrence of mandibular gingival carcinoma. HN-PIT using cylindrical diffusers was performed on the target lesion, extending from the lateral wall of the oropharynx to the soft palate. Case 2 was also a patient in his 70s with carcinoma of the mid-pharynx. HN-PIT was performed using a frontal diffuser to target lesions extending from the soft palate to the buccal mucosa. Notably, both patients developed laryngeal edema after HN-PIT, and an emergency tracheostomy had to be performed.

Conclusion

HN-PIT treatment is still being established through a trial-and-error method and is still incomplete.

A Case of Successful Treatment with an Immune Checkpoint Inhibitor after Head and Neck Photoimmunotherapy

Introduction

Head and neck photoimmunotherapy (HN-PIT) has been conditionally approved by the Japanese government for the treatment of unresectable locally advanced or locally recurrent head and neck cancer since January 2021. HN-PIT makes local treatment of locally recurrent disease possible in cases where systemic drug therapy would have previously been the only option. However, when treatment is ineffective and the disease progresses, it is necessary to shift to conventional drug therapies. We report a case in which an immune checkpoint inhibitor (ICI) was successfully administered to a patient with advanced disease following HN-PIT.

Case Presentation

A 75-year-old male patient presented with local recurrence of mandibular gingival cancer. The primary treatment consisted of mandibular segmentectomy and reconstruction with a scapulohumeral and vastus lateralis skin valve. Post-operative radiotherapy was administered. Local recurrence was found in the mid-pharynx adjacent to the reconstruction. HN-PIT was performed for the local recurrence. After three cycles of HN-PIT, the local lesion increased, and the disease was evaluated as advanced. Therefore, the patient was switched to pembrolizumab, an ICI.

Conclusion

The recurrent lesions disappeared 2 months after the first dose of pembrolizumab, and the patient remained in clinical remission at 1 year. To the best of our knowledge, there are no other reports of successful ICI therapy after HN-PIT.

Lemierre's Syndrome after Head and Neck Photoimmunotherapy for Local Recurrence of Nasopharyngeal Carcinoma

Introduction

Head and neck photoimmunotherapy (HN-PIT) uses a combination of drugs and laser illumination to specifically destroy tumor cells. Lemierre's syndrome is an infectious disease with severe systemic symptoms caused by prior infection in the pharyngeal region, leading to thrombophlebitis. Here, we report a case of Lemierre's syndrome that developed after HN-PIT for recurrent nasopharyngeal carcinoma.

Case Presentation

A 68-year-old male with nasopharyngeal carcinoma (squamous cell carcinoma) underwent HN-PIT after local recurrence with chemoradiation therapy. Three months after HN-PIT, the patient developed fever and neck pain, which led to a diagnosis of Lemierre's syndrome. The patient was treated with antibiotics and anticoagulants for at least 1 month. The patient's general condition and inflammatory findings on blood sampling showed gradual improvement, and a follow-up cervicothoracic computed tomography imaging showed that the venous thrombus had been obscured and the patient was doing well.

Conclusion

HN-PIT is a high-risk procedure for the development of Lemierre's syndrome due to irradiation-induced mucositis, and anticipating the development of Lemierre's syndrome during HN-PIT is important.

Eligibility for Photoimmunotherapy in Patients with Unresectable Advanced or Recurrent Head and Neck Cancer and Changes before and after Systemic Therapy

Photoimmunotherapy is a novel cancer treatment that recently became covered by national health insurance in Japan, but treatment decision-making remains challenging for unresectable advanced or recurrent head and neck cancer. We aimed to clarify the characteristics of patients for whom photoimmunotherapy was indicated by a retrospective chart review. Patients aged ≥20 years diagnosed with advanced or recurrent head and neck cancer who started receiving systemic therapy at the National Cancer Center Hospital East from January 2016 through December 2020 were retrospectively analyzed. Before and after first-line systemic therapy, patients were classified into 3 groups according to eligibility for photoimmunotherapy: eligible, potentially eligible, and ineligible. In total, of 246 patients evaluated-194 after exclusions were analyzed-108 were deemed ineligible for treatment. Of the remaining 86 patients, 8 were considered potentially eligible and 9 eligible. Of the nine eligible patients, four became ineligible after receiving first-line systemic therapy due to disease progression. Our results suggest that the indication of photoimmunotherapy should be considered before, during, and after systemic therapy for unresectable locally advanced or recurrent head and neck cancer.

Quality-of-Life Evaluation of Patients with Unresectable Locally Advanced or Locally Recurrent Head and Neck Carcinoma Treated with Head and Neck Photoimmunotherapy

Simple Summary

Head and neck photoimmunotherapy (HN-PIT) is a new treatment developed for local control of head and neck carcinoma. This study assessed the quality of life (QOL) of nine patients with unresectable locally advanced or locally recurrent head and neck carcinoma (LA/LR-HNC) treated with HN-PIT. QOL was compared before and 4 weeks after HN-PIT. There were no significant changes in all the QOL assessment parameters after treatment with HN-PIT. For patients with unresectable LA/LR-HNC, HN-PIT provided good local control without decreasing the QOL.

Abstract

Head and neck photoimmunotherapy (HN-PIT), a new treatment developed for local control of head and neck carcinoma, uses cetuximab sarotalocan sodium with a laser system to specifically destroy only tumor cells. No studies have examined the impact of HN-PIT on the quality of life (QOL) of patients with head and neck cancer. This study assessed the QOL of patients with unresectable locally advanced or locally recurrent head and neck carcinoma (LA/LR-HNC) treated with HN-PIT. Nine eligible patients with unresectable LA/LR-HNC who underwent HN-PIT at our institution between 20 January 2021 and 30 April 2022 were included in the study. They completed a QOL evaluation form. The primary endpoint was QOL assessment. The secondary endpoints were overall response rate, overall survival (OS), progression-free survival, and adverse events. QOL was compared before and 4 weeks after HN-PIT. There were no significant changes in all QOL assessment parameters after treatment with HN-PIT. The overall response rate was 89%, and safety was acceptable. For patients with unresectable LA/LR-HNC, HN-PIT provided good local control without decreasing the QOL. The addition of HN-PIT to conventional head and neck carcinoma treatment may lead to the prolongation of OS in head and neck carcinoma.

Transnasal photoimmunotherapy with cetuximab sarotalocan sodium: Outcomes on the local recurrence of nasopharyngeal squamous cell carcinoma

Photoimmunotherapy for head and neck cancer (HNC-PIT) is a newly developed locoregional treatment targeting the epidermal growth factor. This treatment consists in administering cetuximab sarotalocan sodium that conjugates cetuximab with the dye IRdye700DX, which is activated by near-infrared ray illumination at 690 nm. HNC-PIT has been conditionally approved in Japan in September 2020 for the treatment of unresectable locally advanced or unresectable locoregionally recurrent HNC. However, its outcomes on the local recurrence of the nasopharyngeal squamous cell carcinoma (NPSCC) remain undetermined. In this report, we assessed the effects of HNC-PIT assisted by transnasal endoscopy on the local recurrence of NPSCC. A 77-year-old male presented with a local recurrence of NPSCC. The initial diagnosis revealed a squamous cell carcinoma, T2N2M0 stage III, positive for Epstein-Barr virus-encoded small RNA by in situ hybridization, which was treated with concurrent chemoradiotherapy (CRT). However, local recurrence was detected 14 months after CRT. We performed HNC-PIT under transnasal endoscopy. Seven months have passed since the HNC-PIT treatment, and the patient is alive without delayed adverse events and evidence of recurrence. Local recurrence of NPSCC, which is difficult to treat with minimally invasive surgery, is considered a potential candidate for HNC-PIT.

Near-Infrared Photoimmunotherapy (NIR-PIT) in Urologic Cancers

Near-infrared photoimmunotherapy (NIR-PIT) is a novel molecularly-targeted therapy that selectively kills cancer cells by systemically injecting an antibody-photoabsorber conjugate (APC) that binds to cancer cells, followed by the application of NIR light that drives photochemical transformations of the APC. APCs are synthesized by selecting a monoclonal antibody that binds to a receptor on a cancer cell and conjugating it to IRDye700DX silica-phthalocyanine dye. Approximately 24 h after APC administration, NIR light is delivered to the tumor, resulting in nearly-immediate necrotic cell death of cancer cells while causing no harm to normal tissues. In addition, NIR-PIT induces a strong immunologic effect, activating anti-cancer immunity that can be further boosted when combined with either immune checkpoint inhibitors or immune suppressive cell-targeted (e.g., regulatory T cells) NIR-PIT. Currently, a global phase III study of NIR-PIT in recurrent head and neck squamous cell carcinoma is ongoing. The first APC and NIR laser systems were approved for clinical use in September 2020 in Japan. In the near future, the clinical applications of NIR-PIT will expand to other cancers, including urologic cancers. In this review, we provide an overview of NIR-PIT and its possible applications in urologic cancers.