11.1 Introduction

In the Unites States, there are approximately 3,800 patients diagnosed with oral cancer annually. ¹ Patients with oral cancers have a significant risk of dysphagia and speech problems. ^{2 , 3} These deficits can be the result of tumor burden, surgery, and/or adjuvant radiation and chemotherapy. Speech-language pathology (SLP) intervention can be beneficial both pre- and postoperatively, as well as during the course of adjuvant treatments. ^{4 – 6}

The purpose of SLP involvement includes pretreatment counseling and evaluation and posttreatment intervention as indicated. Posttreatment considerations will be discussed in Chapter 44.

Pretreatment counseling has been a standardized part of head and neck cancer teams for many years. Although historically SLP pretreatment involvement began for total laryngectomy, ⁷ the value of pretreatment counseling is well documented for patients with oral cavity cancers as well. ^{4 , 5} Meeting with patients prior to cancer treatment allows the SLP to obtain baseline data on speech and swallowing, ease patients’ and families’ anxiety about what to expect, set appropriate and realistic posttreatment goals, introduce exercises or interventions, and establish rapport with the patient and family. ^{2 , 4 , 5 , 8 , 9}

More recently, involvement of a speech pathologist at the pretreatment stage has become standard for head and neck cancer patients undergoing radiation ± chemotherapy. ^{8 , 10} Introduction to prophylactic swallowing and oral exercises and pretreatment swallowing evaluations are the standard of care in most head and neck cancer centers and increasingly now in smaller, community hospitals providing chemoradiation therapy (CRT) for patients with head and neck cancer. ¹¹ Prehabilitation is now common in cancer treatment and improves functional outcomes and compliance. ^{11 , 12}

Unfortunately, pretreatment evaluations by SLPs are not always standard protocol for patients with oral cancer. While patients undergoing total or subtotal glossectomy (Video 11.1) are referred more often for a pretreatment evaluation, those expected to have partial glossectomyies, floor of mouth resections, and palatal or mandibular resections do not often see an SLP until after surgery. ¹³ We believe the value of SLP involvement at the pretreatment stage can improve outcomes for the majority of patients undergoing surgical or nonsurgical treatment for oral cancer. Similar to patients undergoing CRT for oropharyngeal cancer or those requiring total laryngectomy, patients with oral cancer often have questions regarding posttreatment expected functional outcomes on speech and swallowing. Pretreatment evaluations can establish baseline function, help patients understand possible effects of surgery or CRT on speech and swallowing, and introduce exercises or interventions that may optimize speech and swallowing during and after treatment. ^{4 , 5 , 8 , 9} SLPs are often an important connection to other team members such as dieticians, dentists, prosthodontists, social workers, nurses, physical therapists, and certainly the physicians involved in definitive and adjuvant treatments. Additionally, multidisciplinary teams have been shown to be beneficial for patients with all types of head and neck cancer. ^{14 , 15} There has been an increase in the number of multidisciplinary teams where patients can see all their practitioners in one setting, rather than having individual evaluations. This has been shown to improve patient compliance and understanding of the SLP’s role in their treatment. ^{14 , 15}

11.2 Incidence and Clinical Characteristics

There are few studies assessing the exact incidence of dysphagia and dysarthria in the oral cancer population; however, Colangelo and colleagues suggest that self-reported dysphagia and dysarthria are present in at least 34% of oral cancer patients prior to treatment. ¹³ Most studies combine head and neck cancers without differentiating between oral, oropharyngeal, and other cancers. ^{14 , 16 , 17} Further, since treatments are now often combined modalities, it is similarly hard to specify functional problems related to surgery versus chemoradiation. Additionally, many patients with speech or swallowing problems after oral cancer treatment may go unrecognized or untreated. Regardless, patients with oral cancer treated with surgery, nonsurgical treatment, or combined modalities can have deficits with any of the following: dysarthria or articulation problems, oral and/or pharyngeal dysphagia, resonance disorders, and trismus. ¹⁸

11.3 Clinical Presentation and Anatomic Considerations

Clinical characteristics vary depending on tumor location and tumor size. As suspected, larger tumors result in greater deficits in speech and/or swallowing. ¹⁹ Dysarthria occurs when speech intelligibility is impacted, whereby speech is more difficult to understand, or unintelligible. Patients who have oral tongue tumors tend to experience the greatest speech disturbance of all the oral cancers. ²⁰ This is because the tongue is our primary articulator. Anticipated speech and swallow deficits postoperatively are discussed with the patient during the initial preoperative visit. Patients are educated on likelihood of surgery having an impact on their articulation. The main point of preoperative education is for patients to understand that initial speech quality and articulation postoperatively will change and improve as edema decreases and lingual strength, tone, and range of movement increase. ^{4 , 21 , 22} This is usually gradual over weeks and months, and patients should understand preoperatively that realistic optimism is an ideal goal. Within the oral cavity, there are a variety of tumor locations, each with different potential impact of the tumor and its treatment on speech and swallowing, as briefly outlined below. Specific posttreatment considerations will be discussed further in Chapter 44.

Resection of cancers of the lip(s) will impact articulation of bilabial consonants (/p,b,w,m/), labiodental consonants (/f,v/), and fricatives that rely on lip rounding (/sh/). ^{23 , 24} The oral preparatory or oral phases of swallowing may be affected, resulting in incomplete lip closure and labial leakage. ²¹

Resection of cancers of the alveolus or mandible may affect mastication. Unless severe, it is generally easy to compensate for partial alveolar or mandibular resections with little to no impact on speech and temporary impact on oral preparatory or oral phase of swallowing. ^{24 , 25}

Maxillary tumor resection can impact oral resonance and result in reduced oral pressure for chewing and swallowing. ²⁶ These deficits are often temporary until an obturator can be made by a maxillofacial prosthodontist or a surgical flap is placed by a maxillofacial plastic surgeon. ^{24 , 27} Typically, patients with maxillary and mandibular tumors do not have preoperative dysarthria, with the exception of “muffled or mumbled speech,” as the result of pain when speaking. In this instance, there is sometimes guarding or trying to move articulators minimally and keep mouth in a closed posture when speaking. The resulting impact on intelligibility is usually mild. ²⁷

Floor of mouth cancers and their treatment can affect swallowing since many of the laryngeal elevation muscles originate there. ²⁸ Laryngeal elevation is an important component of airway protection. ²⁵ Anterior and superior movement of the hyolaryngeal musculature allows for epiglottic inversion and airway protection before and during swallowing. ²⁹ This may be seen as problems with thin liquid swallowing in the immediate postoperative period. ²¹

Cancers of the retromolar trigone or areas requiring composite resection with or without adjuvant nonsurgical treatments may result in oral preparatory or oral phase problems. ²⁴ As most of these cancers are unilateral, temporary postures and maneuvers are often helpful. ³⁰

Predicting impact on speech and swallowing for patients requiring partial glossectomy is directly related to the amount and location of tumor and resulting resection. ¹³ Tumors confined to the anterior tongue will result in speech deficits for lingual-alveolar consonants /t,d,n,l,s,z/ and “ʃ, d͡ʒ, t͡ʃ.” ^{24 , 27} Oral preparatory and oral phases may be affected for swallowing. Unilateral deficits up to and including hemiglossectomy will have noticeable effects on consonant production requiring elevation of the lateral portion of the tongue (/s,z,sh,ch,j/). ^{24 – 27} Resulting dysarthria is often characterized by a lateral lisp. Similarly, loss of the bolus during the oral preparatory phase is common as is difficulty forming and transferring the bolus and oral residue after the swallow. ²¹ Large oral tongue tumors may result in significant lingual edema with limited tongue mobility and therefore reduced articulatory precision of lingual, lingua-dental, lingua-alveolar, and velar phonemes, including /t, d, n, l, s, z, k.g/. ²⁴

Total glossectomy results in much greater deficits for speech, with not only most consonants affected (other than bilabials), but impact on vowel production. ³¹ Despite the potentially large impact on specific sounds, speech can be quite intelligible for a patient undergoing total glossectomy. ³² This should be addressed in the preoperative session as many patients assume they “will never be able to speak.” Patients are also educated on the use of augmentative and alternative communication options, which are beneficial in the immediate postoperative period and possibly long term. Similarly, patients can resume complete oral nutrition after total glossectomy with the right combination of reconstruction, speech/swallow therapy, prosthodontic intervention, and use of compensatory utensils and strategies. ^{29 – 33}

Patients who will be undergoing free-flap reconstruction are advised on the anticipated large “bulky” flap ³⁴ and significant postoperative speech disturbances. ^{22 , 31} Regardless of the location of oral tumors, many patients with oral cancer require free-flap reconstruction ³⁵ and therefore at least temporary speech deficits are anticipated.

If a tracheostomy is anticipated in conjunction with the surgery, the patient is educated on the anatomy and changes to physiology with the presence of a tracheostomy tube or cannula. We discuss the anticipated duration of the tracheostomy, downsizing, use of a speaking valve, and potentially the decannulation process. The amount of education, as with everything else during these sessions, varies depending on the patient and their family’s comprehension, level of education, literacy, and emotional state as well as the exact anticipated surgery.

Trismus is tonic contraction of the muscles of mastication, mainly the pyterygoids. ^{36 , 37} It can be the result of tumor burden, surgery, and/or radiation. Intraoral opening is evaluated preoperatively by obtaining an interincisor or oral aperture measurement as discussed below. Trismus is not typically treated preoperatively, but rather only evaluated. Patients are educated on the potential development of trismus and types of treatments that could be expected postoperatively or throughout a course of radiation therapy (RT). As interincisor measurements vary widely, it is important to obtain a baseline measurement in the pretreatment evaluation.