There are three main parts of the larynx: the glottis (the middle part of the larynx where the vocal cords are located), the supraglottis (the tissue above the glottis) and the subglottis (the tissue below the glottis). The subglottis connects to the trachea, which takes air to the lungs.
Stage 0 (also called carcinoma in situ) is non-invasive cancer limited to the cells that line the larynx, and has not spread to lymph nodes in the area or to distant sites.
Supraglottis: The cancer is only in one area of the supraglottis and the vocal cords are normal.
Glottis: The cancer is in the vocal cords and the vocal cords can move normally.
Subglottis: The cancer has not spread outside the subglottis.
A variety of factors ultimately influence a patient’s decision to receive treatment of cancer. The purpose of receiving cancer treatment may be to improve symptoms through local control of the cancer, increase a patient’s chance of cure, or prolong a patient’s survival. The potential benefits of receiving cancer treatment must be carefully balanced with the potential risks of receiving cancer treatment.
The following is a general overview of the treatment of stage 0 cancer of the larynx. Circumstances unique to your situation and prognostic factors of your cancer may ultimately influence how these general treatment principles are applied. The information on this Web site is intended to help educate you about your treatment options and to facilitate a mutual or shared decision-making process with your treating cancer physician.
Most new treatments are developed in clinical trials. Clinical trials are studies that evaluate the effectiveness of new drugs or treatment strategies. The development of more effective cancer treatments requires that new and innovative therapies be evaluated with cancer patients. Participation in a clinical trial may offer access to better treatments and advance the existing knowledge about treatment of this cancer. Clinical trials are available for most stages of cancer. Patients who are interested in participating in a clinical trial should discuss the risks and benefits of clinical trials with their physician. To ensure that you are receiving the optimal treatment of your cancer, it is important to stay informed and follow the cancer news in order to learn about new treatments and the results of clinical trials.
Surgery
Carcinoma in situ (stage 0) and severe dysplasia (precancer) of the glottis may be treated by surgical stripping of the vocal cords or endoscopic laser surgery. There is a trend toward the exclusive use of laser surgery for this stage of larynx cancer as described below.
Laser Surgery: A laser beam can be used instead of a scalpel to remove stage 0 cancers or severe dysplasia of the larynx.A retrospective review of 12 cases of carcinoma in situ of the glottis treated with laser surgery showed a 100 percent preservation rate of the larynx.1 Initial control rate with laser surgery was 75 percent but with repeat treatment the ultimate control rate was 100 percent. In a study of 19 patients from Italy, the three-year control rate following laser surgery for carcinoma in situ was 100 percent.2 Based on these and other studies, recommended treatment for cancer in situ is laser removal of the cancer in combination with a meticulous follow-up for early recognition of local recurrence.
Radiation Therapy
Until the advent of laser surgery, radiation therapy was frequently used in the initial treatment of carcinoma in situ of the larynx. A Canadian study reported a five-year control rate of 98 percent in 67 patients with carcinoma in situ treated with radiation therapy.3 Twenty-one of these patients had failed surgical stripping. Despite the effectiveness of radiotherapy in treating carcinoma in situ, most guidelines suggest that laser surgery be used first.4
For more information, go to Radiation Therapy for Head & Neck Cancer.
Strategies to Improve Treatment
The progress that has been made in the treatment of early cancer of the larynx has resulted from early diagnosis, improved surgical and radiation therapy techniques, as well as participation in clinical studies. Future progress in the treatment of early cancer of the throat will result from patients and doctors continuing to participate in appropriate studies. Areas of active exploration to improve the treatment of cancer of the larynx include the following:
Photodynamic Therapy: The concept behind photodynamic therapy is that light from a laser, enhanced by photosensitizing agents (agents that make cells sensitive to light), can kill cancer cells without damage to normal cells. The basic technique is over 50 years old, but the past five years have seen the development of reliable, portable lasers and better photosensitizing agents, making the technique quick, effective and relatively free from side-effects. For some patients with head and neck cancer, functional outcomes with photodynamic therapy may be improved over that observed with surgery and radiation therapy.
In one study, complete responses were observed in eight of 10 patients with superficial laryngeal cancers treated with photodynamic therapy.5 In another study, phototherapy was used successfully to treat leukoplakia.6
Cryosurgery: Cryoablation (freezing) is being increasingly used to treat a variety of cancers including laryngeal cancer. In one study, the combination of laser and cryotherapy was used to treat early-stage laryngeal cancer.7
References:
1 De Mones E, Hans S, Hartl DM et al. Carbon dioxide laser transoral microsurgery for glottic carcinoma in situ. Annals Otolaryngol Chir Cervicofac 2002;119:21-30.
2 Gallo A, de Vincentiis M, Manciocco V, et al. CO2 laser cordectomy for early-stage glottic carcinoma: a long-term follow-up of 156 cases. Laryngoscope 2002;112:370-374.
3 Spayne JA, Worde P O’Sullivan B, et al. Carcinoma-in-situ of the glottic larynx: results with treatment with radiation therapy. International Journal of Radiation Oncology Physics 2001;49:1235-1238.
4 Kaanders JH, Hordijk GJ:Dutch Cooperative Head and Neck Oncology Group. Carcinoma of the larynx: the Dutch national guideline for diagnostics, treatment, supportive care and rehabilitation. Radiotherapy Oncology 2002;63:299-307.
5 Schweitzer VG. PHOTOFRIN-mediated photodynamic therapy for treatment of early stage oral cavity and laryngeal malignancies. Lasers Surg Med 2001;29:305-313.
6 Sieron A, Namyslowski G, Misiolek M, et al. Photodynamic therapy of premalignant lesions and local recurrence of laryngeal and hypopharyngeal cancers. Eur Arch Otophinolaryngol 2001;258:349-352.
7 Knott PD, Milstein CF, Hicks DM, et al. Vocal outcomes after laser resection of early-stage glottic cancer with adjuvant cryotherapy. Arch Otolaryngol Head and Neck Surg 2006;132:1226-1230.