Dental and swallowing evaluations are also part of the pretreatment workup. Such evaluations help identify a patient’s risk for dysphagia and aspiration, which can affect treatment choice, and provide a guide for post-treatment rehabilitation. Like vocal function tests, a thorough swallowing evaluation will help determine which treatment might cure the disease while best preserving function. Testing should be completed before treatment decisions are made, as pretreatment swallowing abilities are often helpful in predicting long-term swallowing abilities beyond 1 year after treatment. Treatment choices Radiation therapy For laryngeal cancers, radiation is typically deliv-
Early-Stage Laryngeal Cancer: Primary Treatment Options
Variables considered for each patient
Outcome-based, standard treatment options
Partial laryngectomy • Open/conventional surgery, or • Endoscopic surgery
• General health • Comorbidities
• Treatment length • Functional status (voice and swallowing) • Patient preferences
Surgery
Diagnosis: Early-Stage Laryngeal Cancer
(transoral laser microsurgery)
OR
External-beam radiation (3-dimensional conformal or intensity-modulated radiation therapy)
Radiation Therapy
rect laryngoscopy using a surgical carbon dioxide (CO 2 ) laser beam and aided by a microscope. The use of a CO 2 laser is par- ticularly important; water in the body absorbs the light energy in a way that minimizes collateral injury to adjacent neurovas- cular, mucosal, and muscular structures. According to Dr. Holsinger, TLM represents a truly mini- mally invasive alternative for some patients. The larynx is ac- cessed via a laryngoscope inserted through the patient’s mouth, so a surgical incision is not needed. The surgeon “follows the tumor” along its anatomic boundaries to assess its margins. The laser vaporizes tissue so that the margins can be seen without carbonization from cautery. For selected patients, Dr. Holsinger points out, the tumor may be divided to identify the depth of invasion and to help the surgeon determine the appropriate extent of resection. This approach certainly challenges the long-held “en bloc” tenet of oncologic surgery, but it allows TLM to be used for larger tumors than would be possible with en bloc resection, given the restricted anatomical spaces of the neck and throat. It should be clarified that TLM is not an ablative procedure but rather a true resection. The tumor can be studied patholog- ically—an advantage over radiation therapy. TLM offers many other advantages: it is usually a one-time treatment, and it can successfully cure early-stage cancer, but it does not preclude future treatment options—patients can have radiation or additional surgery if the tumor recurs. “It does not burn a bridge,” Dr. Holsinger explained. Also, the recovery time is minimal compared to conventional surgeries; TLM is usually done as a day surgery when used as a primary treatment for early-stage cancers. Most patients are able to speak and eat immediately after surgery and can return to normal activities within a week. Today, most TLM procedures for laryngeal cancer are per- formed for tumors that have recurred after primary radiation treatment; in such cases, TLM may be an alternative to total laryngectomy. Unfortunately, 70% of the patients with early- and intermediate-stage larynx cancer who have a recurrence after radiation will require a total laryngectomy. 1,2 Because of its significant advantages, TLM is now consid- ered a primary treatment option for early-stage laryngeal cancer at M. D. Anderson, said Randal S. Weber, M.D., a
ered by external beam. At M. D. Anderson, three-dimensional (3-D) conformal or intensity-modulated radiation therapy (IMRT) is used. Both technologies finely focus radiation to a tar- get area, sparing surrounding normal tissues and allowing the tumor tissue to receive higher doses of radiation. The 3-D confor- mal technique shapes the beam to the tumor target, while IMRT can vary (or modulate) the intensity of the beam as best suited to the target and surrounding normal structures. These technologies are particularly useful for patients whose tumors are near impor- tant structures that might be damaged by radiation. Damage to the salivary glands, for example, can result in long-term xerosto- mia. According to David I. Rosenthal, M.D., a professor in the Division of Radiation Oncology, the radiation oncologist se- lects the delivery method based on the location and size of the tumor as well as patient factors, with the aim of optimizing tumor treatment while minimizing long-term effects. Patients typically have radiation treatments once, or in some cases twice, each day over a period of 5½–7 weeks. Radiation therapy is considered a standard primary treat- ment for early-stage laryngeal cancer because it can cure 80%–90% of such tumors while preserving a high-quality voice. Also, patients who have a recurrence after radiation therapy can usually be treated successfully with surgery, boost- ing the overall cure rate for patients who receive primary radiation therapy to 95%. Surgery The standard surgical treatment for early-stage laryngeal cancer is partial laryngectomy with resection of the entire tumor. Conventional procedures include vertical partial laryn- gectomy and supraglottic laryngectomy; the choice of the spe- cific procedure depends on tumor location. The preparation for and recovery from partial laryngectomy procedures are similar those for total laryngectomy, but partial laryngectomy requires only a temporary tracheostomy. Conservation techniques that can preserve laryngeal function may also be an option. Supra- cricoid partial laryngectomy is one such technique. Another type of conservation surgery—transoral laser microsurgery (TLM)—has recently gained acceptance as an alternative to conventional surgery for early-stage (and inter- mediate-stage) laryngeal cancer. TLM is performed under di-
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www.mdanderson.org/oncolog • OncoLog 5
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