Temoporfin mediated photodynamic therapy in patients with local persistent and recurrent nasopharyngeal carcinoma after curative radiotherapy: A feasibility study

Photodynamic therapy in oral cancer: a review of clinical studies

A significant mortality rate is associated with oral cancer, particularly in cases of late-stage diagnosis. Since the last decades, oral cancer survival rates have only gradually improved despite advances in treatment. This poor success rate is mainly due to the development of secondary tumors, local recurrence, and regional failure. Invasive treatments frequently have a negative impact on the aesthetic and functional outcomes of survivors. Novel approaches are thus needed to manage this deadly disease in light of these statistics. In photodynamic therapy (PDT), a light-sensitive medication called a photosensitizer is given first, followed by exposure to light of the proper wavelength that matches the absorbance band of the photosensitizer. The tissue oxygen-induced cytotoxic free radicals kill tumor cells directly, harm the microvascular structure, and cause inflammatory reactions at the targeted sites. In the case of early lesions, PDT can be used as a stand-alone therapy, and in the case of advanced lesions, it can be used as adjuvant therapy. The current review article discussed the uses of PDT in oral cancer therapy based on recent advances in this field.

Treatment of Recurrent Nasopharyngeal Carcinoma: A Sequential Challenge

Simple Summary

Recurrent nasopharyngeal carcinoma is one of the major causes of death among NPC patients. However, there are no international guidelines for the treatment of patients with recurrent NPC now. In this article, we summarize past publications on clinical research and mechanistic studies related to recurrent NPC, combined with the experience and lessons learned by our institutional multidisciplinary team in the treatment of recurrent NPC. We propose an objective protocol for the treatment of recurrent NPC.

Abstract

Recurrent nasopharyngeal carcinoma (NPC), which occurs in 10–20% of patients with primary NPC after the initial treatment modality of intensity-modulated radiation therapy (IMRT), is one of the major causes of death among NPC patients. Patients with recurrent disease without distant metastases still have a chance to be saved, but re-treatment often carries more serious toxicities or higher risks. For this group of patients, both otolaryngologists and oncologists are committed to developing more appropriate treatment regimens that can prolong patient survival and improve survival therapy. Currently, there are no international guidelines for the treatment of patients with recurrent NPC. In this article, we summarize past publications on clinical research and mechanistic studies related to recurrent NPC, combined with the experience and lessons learned by our institutional multidisciplinary team in the treatment of recurrent NPC. We propose an objective protocol for the treatment of recurrent NPC.

From Basic Mechanisms to Clinical Research: Photodynamic Therapy Applications in Head and Neck Malignancies and Vascular Anomalies

Head and neck cancers are largely squamous cell carcinomas derived from the epithelial lining of the structures in the region, and are often classified anatomically into oral, oropharyngeal, nasopharyngeal and laryngeal carcinomas. The region’s component structures serve complex and intricate functions, such as speaking, swallowing and breathing, which are often compromised by these neoplasms. Such lesions may also cause disfigurement, leading to distressing social and psychological issues. Conventional treatments of these neoplasms usually involve surgical intervention with or without chemoradiotherapy. These have shown to be efficacious; however, they can also cause damage to healthy as well as diseased tissue, exacerbating the aforementioned problems. Access to a given region to deliver the treatments is also often a problem, due to the complex anatomical structures involved. The use of photodynamic therapy in the head and neck region has been established for about two decades. In this review, we looked at the basic mechanisms of this intervention, examined its use in common head and neck malignancies and vascular anomalies, and reported on the most recent clinical studies. We further included a clinical guide which can help replicate the use of this technology by any unit. Based on this review, photodynamic therapy has been shown to be efficacious in the treatment of head and neck malignancies and vascular tumours. This therapy can be targeted to the diseased tissue and causes no damage to underlying structures. Recent studies have shown this therapy to be as effective as conventional therapies, without causing major adverse effects.

Novel Therapies Boosting T Cell Immunity in Epstein Barr Virus-Associated Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant tumour of the head and neck affecting localised regions of the world, with the highest rates described in Southeast Asia, Northern Africa, and Greenland. Its high morbidity rate is linked to both late-stage diagnosis and unresponsiveness to conventional anti-cancer treatments. Multiple aetiological factors have been described including environmental factors, genetics, and viral factors (Epstein Barr Virus, EBV), making NPC treatment that much more complex. The most common forms of NPCs are those that originate from the epithelial tissue lining the nasopharynx and are often linked to EBV infection. Indeed, they represent 75–95% of NPCs in the low-risk populations and almost 100% of NPCs in high-risk populations. Although conventional surgery has been improved with nasopharyngectomy’s being carried out using more sophisticated surgical equipment for better tumour resection, recent findings in the tumour microenvironment have led to novel treatment options including immunotherapies and photodynamic therapy, able to target the tumour and improve the immune system. This review provides an update on the disease’s aetiology and the future of NPC treatments with a focus on therapies activating T cell immunity.

Management of locally recurrent nasopharyngeal carcinoma

As a consequence of the current excellent loco-regional control rates attained using the generally accepted treatment paradigms involving intensity-modulated radiotherapy for nasopharyngeal carcinoma (NPC), only 10-20% of patients will suffer from local and/or nodal recurrence after primary treatment. Early detection of recurrence is important as localized recurrent disease is still potentially salvageable, but this treatment often incurs a high risk of major toxicities. Due to the possibility of radio-resistance of tumors which persist or recur despite adequate prior irradiation and the limited tolerance of adjacent normal tissues to sustain further additional treatment, the management of local failures remains one of the greatest challenges in this disease. Both surgical approaches for radical resection and specialized re-irradiation modalities have been explored. Unfortunately, available data are based on retrospective studies, and the majority of them are based on a small number of patients or relatively short follow-up. In this article, we will review the different salvage treatment options and associated prognostic factors for each of them. We will also propose a treatment algorithm based on the latest available evidence and discuss the future directions of treatment for locally recurrent NPC.

Drug-Loaded Polymer-Coated Graphitic Carbon Nanocages for Highly Efficient in Vivo Near-Infrared Laser-Induced Synergistic Therapy through Enhancing Initial Temperature

Graphitic carbon nanocages (GCNCs) have unique geometric structures and physical properties, which have been extensively investigated for various applications. However, no reports focusing on using GCNCs and polymer-coated GCNCs for solid tumor ablation induced by near-infrared laser irradiation under enhanced initial body temperature, or on the biosafety of GCNCs in vivo, have been published. Here, we developed chitosan (CS)-coated GCNCs and showed that both GCNCs and GCNCs/CS in mouse tumors can rapidly convert an 808 nm laser light energy into heat, which efficiently kill nasopharyngeal carcinoma cells and inhibit tumor growth. The tumors are further damaged by the phototoxicity of GCNCs/CS after loading with 5-Fluorouracil (5FU). Tumors are no longer detected after 6 days of 5FU-GCNCs/CS treatment under irradiation, which is due to the synergistic effect of the photothermal response of GCNCs and the chemotherapy of 5FU. None of the tumors reappeared during the following 12 days of no irradiation. Interestingly, increasing the initial body temperature of the mice significantly improved the photothermal effect of GCNCs in vivo and the synergistic effect of photothermal therapy and chemotherapy, thus accelerating the shrinking of tumors. To the best of our knowledge, this is the first study to improve the photothermal ablation of GCNCs and synergetic photothermal-chemotherapy of drug-loaded GCNCs through enhancing the initial body temperature. As the results show that GCNCs, GCNCs/CS, and 5FU-GCNCs/CS are safe in mice after intratumoral injection both with and without laser irradiation, our technique may have great potential for future clinical translation.

Photodynamic therapy in the upper aerodigestive tract. Overview and outlook

The gold standard in the treatment of (pre)malignancies of the upper aerodigestive tract (UADT) is either surgery or (chemo)radiotherapy. Nevertheless, there are special indications where an alternative treatment, such as photodynamic therapy (PDT), might be as effective for and better tolerated by the patients concerned. This article aims to present a contemporary and comprehensive review on the role of photodynamic therapy in the treatment of (pre)malignancies of the UADT. PubMed was searched for "photodynamic therapy larynx/oral cavity/oropharynx/head and neck" in 01/2016. PDT can be efficient in the treatment of recurrent, residual or multiple carcinomas of the UADT without other treatment options. It has also been used with success in the treatment of early oral or laryngeal carcinomas, widespread precancerous lesions or "difficult-to-treat" skin cancer, even though these treatments are off-label. For now, unsolved scientific and economical challenges hinder the methods spread. In special cases, PDT is a highly effective method to treat head and neck (pre)malignancies. Nevertheless, further clinical studies are needed to better define its true value in head and neck oncology.

Photodynamic therapy as salvage therapy for patients with nasopharyngeal carcinoma experiencing local failures following definitive radiotherapy

BACKGROUND

Treating local failures of nasopharyngeal carcinoma (NPC) is a challenge. This study evaluates photodynamic therapy (PDT) in the treatment of residual and recurrent NPC.

METHOD

In this phase II study, patients with local recurrent or residual NPC after curative intent (chemo-) radiation could be included. Exclusion criterion was a tumour depth more than 10mm. Foscan® 0.15mg/kg was administered intravenously. After 96h, the illumination was performed under local anaesthesia with a nasopharyngeal light applicator. Tumour response was measured 10 weeks after illumination by endoscopy, biopsy and CT-scan. Kaplan-Meier method was used for survival analysis.

RESULTS

Twenty-one patients were included. Fourteen patients were treated for residual disease (67%), and two for recurrent (10%). For five patients this distinction could not be made, due to uncertainty about complete response after initial treatment. The median follow-up time was 32 months. Twenty patients (95%) had a complete response 10 weeks post-treatment. Two patients had recurrent local disease at 5 and 7 months post-PDT. They received another course of PDT, one with success. The 2-year local control rate was 75%, progression free survival was 49% and overall survival was 65%. Nine patients (43%) had no evidence of disease and were in a good clinical condition (ECOG Performance Scale 0) at the end of the study period. No serious adverse events were observed.

CONCLUSION

This study showed that PDT is effective in treating local failures of NPC with a depth of less than 10mm. The treatment was easy to perform under local anaesthesia. Especially in regions were other modalities like radiation and surgery are limited PDT can be a good alternative treatment.

Current treatment options for local residual nasopharyngeal carcinoma

OPINION STATEMENT

Local residual disease occurs in 7-13 % after primary treatment for nasopharyngeal carcinoma (NPC). To prevent tumor progression and/or distant metastasis, treatment is indicated. Biopsy is the "gold standard" for diagnosing residual disease. Because late histological regression frequently is seen after primary treatment for NPC, biopsy should be performed when imaging or endoscopy is suspicious at 10 weeks. Different modalities can be used in the treatment of local residual disease. Interestingly, the treatment of residual disease has better outcomes than treatment of recurrent disease. For early-stage disease (rT1-2), treatment results and survival rates are very good and comparable to patients who had a complete response after the first treatment. Surgery (endoscopic or open), brachytherapy (interstitial or intracavitary), external or stereotactic beam radiotherapy, or photodynamic therapy all have very good and comparable response rates. Choice should depend on the extension of disease, feasibility of the treatment, and doctor's and patient's preferences and experience, as well as the risks of the adverse events. For the more extended tumors, choice of treatment is more difficult, because complete response rates are poorer and severe side effects are not uncommon. The results of external beam reirradiation and stereotactic radiotherapy are better than brachytherapy for T3-4 tumors. Photodynamic therapy resulted in good palliative responses in a few patients with extensive disease. Also, chemotherapeutics or the Epstein-Barr virus targeted therapies can be used when curative intent treatment is not feasible anymore. However, their advantage in isolated local failure has not been well described yet. Because residual disease often is a problem in countries with a high incidence of NPC and limited radiotherapeutic and surgical facilities, it should be understood that most of the above mentioned therapeutic modalities (radiotherapy and surgery) will not be readily available. More research with controlled, randomized trials are needed to find realistic treatment options for residual disease.

Primary treatment results of Nasopharyngeal Carcinoma (NPC) in Yogyakarta, Indonesia

Introduction

Nasopharyngeal Carcinoma (NPC) is a major health problem in southern and eastern Asia. In Indonesia NPC is the most frequent cancer in the head and neck area. NPC is very sensitive to radiotherapy resulting in 3-year disease-free and overall survival of approximately 70% and 80%, respectively. Here we present routine treatment results in a prospective study on NPC in a top referral; university hospital in Indonesia.

Methods

All NPC patients presenting from September 2008 till January 2011 at the ear, nose and throat (ENT) department of the Dr. Sardjito General Hospital, Universitas Gadjah Mada, Yogyakarta, Indonesia, were possible candidates. Patients were included if the biopsy was a histological proven NPC without distant metastasis and were assessed during counselling sessions prior to treatment, as being able to complete the entire treatment.

Results

In total 78 patients were included for treatment analysis. The median time between diagnosis and start of radiotherapy is 120 days. Forty-eight (62%) patients eventually finished all fractions of radiotherapy. The median duration of the radiotherapy is 62 days for 66 Gy. Median overall survival is 21 months (95% CI 18–35) from day of diagnosis.

Conclusion

The results presented here reveal that currently the treatment of NPC at an Indonesian hospital is not sufficient and cannot be compared to the treatment results in literature. Main reasons for these poor treatment results are (1) a long waiting time prior to the start of radiotherapy, (2) the extended overall duration of radiotherapy and (3) the advanced stage of disease at presentation.

Self-assembled liposomal nanoparticles in photodynamic therapy

Photodynamic therapy (PDT) employs the combination of non-toxic photosensitizers (PS) together with harmless visible light of the appropriate wavelength to produce reactive oxygen species that kill unwanted cells. Because many PS are hydrophobic molecules prone to aggregation, numerous drug delivery vehicles have been tested to solubilize these molecules, render them biocompatible and enhance the ease of administration after intravenous injection. The recent rise in nanotechnology has markedly expanded the range of these nanoparticulate delivery vehicles beyond the well-established liposomes and micelles. Self-assembled nanoparticles are formed by judicious choice of monomer building blocks that spontaneously form a well-oriented 3-dimensional structure that incorporates the PS when subjected to the appropriate conditions. This self-assembly process is governed by a subtle interplay of forces on the molecular level. This review will cover the state of the art in the preparation and use of self-assembled liposomal nanoparticles within the context of PDT.