Laryngeal cancer is a type of cancer that affects the vocal cords, sound production, and even difficulty in breathing. Although it is a relatively rare form of cancer, it can be a debilitating and life-threatening disease if not treated promptly and effectively. While numerous treatment alternatives are available, one innovative and promising approach is photodynamic therapy. This non-invasive, light-based therapy has demonstrated great potential in the treatment of laryngeal cancer, giving patients a new hope .
In this blog, we will delve into the world of photodynamic therapy, along with the mechanism of action, effectiveness, and the role of photodynamic therapy in laryngeal cancer treatment.
Insight on laryngeal cancer
Laryngeal cancer originates in the larynx, the organ responsible for producing sound and controlling voice. It mostly affects those who smoke, drink too much alcohol, or are exposed for an extended period to other risk factors, like viruses and environmental toxins. Hoarseness of voice, difficulty in swallowing, throat pain, and prolonged coughing are all signs of laryngeal cancer. For increasing the likelihood of a favorable outcome from treatment, early diagnosis and intervention are crucial [1,2].
Traditional treatment approaches
Laryngeal cancer treatment typically comprises a combination of surgery, radiation therapy, and chemotherapy. Surgery may include partial or total laryngectomy, where a part or the entire larynx is removed. Although these conventional therapies have a history of success, they often come with severe side effects, such as speech and swallowing difficulties, reduced quality of life, and considerable physical and psychological distress for the patient.
Moreover, additional adjuvant therapies like chemotherapy and radiation therapy are frequently required after surgical resection. Both of these treatments have several side effects, including nausea, vomiting, fatigue, weight loss, and hair loss [1,2].
What is photodynamic therapy?
Due to its potential for high cancer selectivity, photodynamic therapy has emerged as a promising alternative cancer therapy. Photodynamic therapy is based on three key elements including photosensitizers, a specific light wavelength, and a sufficient amount of molecular oxygen.
Photosensitizer is a drug that is administered into the patient's bloodstream and then absorbed by the cancer cells. When the cancer cells are exposed to a specific wavelength of light, the photosensitizing agent becomes activated and produces a cytotoxic reactive oxygen species leading to tumor destruction [3,4].
Is photodynamic therapy reshaping laryngeal cancer care?
Even though the precise mechanisms underlying the selective tumor localization of photodynamic therapy in cancer are not fully understood, characteristics specific to tumors, such as leaky vasculature, lowered pH, overexpressed low-density lipoproteins, and inadequate lymphatic drainage, are thought to enhance the selectivity .
Numerous clinical studies and trials have revealed the effectiveness of photodynamic therapy in treating laryngeal cancer. Photodynamic therapy has a high success rate in early-stage patients, often comparable to or even better than traditional treatments. Phase Ib clinical trial has demonstrated the efficacy of photodynamic therapy to treat early-stage patients with squamous cell carcinoma of the larynx with a complete response rate of 82% at the maximum tolerated dose .
The unique benefits of photodynamic therapy
Photodynamic therapy has several advantages over traditional cancer treatments in addition to its cancer selectivity, such as:
It offers a less invasive method of treatment, which reduces the physical and psychological trauma for patients.
Photodynamic therapy can reduce harm to the surrounding healthy tissue, maintaining laryngeal function and raising the patient’s quality of life.
It can be repeated as required due to fewer side effects, low recurrence rates, and high success rates, compared to chemotherapy and radiation therapy.
Photodynamic therapy easily synergizes with numerous other cancer treatments, increasing their efficacy while maintaining other treatment modalities.
It frequently leaves little to no significant scarring or sequelae.
It offers shorter treatment times, more patient convenience, reduced hospital stays, and the associated costs.
As a result, photodynamic therapy has surfaced as an appealing and promising alternative for cancer treatment [3,4].
Challenges and considerations
Even though photodynamic therapy has a lot of potential for treating laryngeal cancer, the following aspects must be taken into account:
Tumor size and stage: Photodynamic therapy is most effective in treating early-stage laryngeal cancer or small, localized tumors. Cancers in advanced stages may need a combination of therapeutic modalities.
Location of the tumor: The location of the tumor within the larynx is an important consideration in determining the feasibility of photodynamic therapy.
Photosensitizer choice: The effectiveness of photodynamic therapy may vary depending on the type of photosensitizing agent used. The best agent for each case will be chosen by healthcare professionals.
Adverse effects: Photodynamic therapy usually has fewer side effects, but patients may experience light sensitivity and skin reactions to the photosensitizing agent [3,4].
Is the future of photodynamic therapy promising?
Photodynamic therapy represents a shining beacon of hope in the treatment of laryngeal cancer. With its non-invasive nature, minimal side effects, and the potential for preserving vital laryngeal function, photodynamic therapy is revolutionizing the approach to laryngeal cancer treatment. As research in this field continues to progress, photodynamic therapy may offer new hope for improved outcomes and a higher quality of life.
1. Koroulakis, A. et al. 'Laryngeal Cancer' [https://www.ncbi.nlm.nih.gov/books/NBK526076/]. In: StatPearls, StatPearls Publishing, Treasure Island (FL) (2023) [cited 2023 Oct 20].
2. 'Laryngeal Cancer Treatment - NCI' [https://www.cancer.gov/types/head-and-neck/hp/adult/laryngeal-treatment-pdq]. (2023).
3. Kim, T.E. et al. 'Recent Studies in Photodynamic Therapy for Cancer Treatment: From Basic Research to Clinical Trials'. Pharmaceutics. (2023) 15(9), 2257. DOI: 10.3390/pharmaceutics15092257.
4. Shafirstein, G. et al. 'Photodynamic therapy with 3-(1′-hexyloxyethyl) pyropheophorbide-a for early-stage cancer of the larynx: Phase Ib study'. Head & Neck. (2016) 38(S1), E377–E383. DOI: 10.1002/hed.24003.