Goroll_Primary Care Medicine, 8e

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SECTION XIV Ear, Nose, and Throat Problems

radiation. They are more common on the lower lip of fair skinned individuals with chronic sun exposure and less com mon in women, in part probably due to the protective effect of lipstick. The presence of actinic cheilitis appears to double the risk of developing lip cancer. Malignant Disease Early, localized oral cancer may be only mildly symptomatic, presenting as a small “bump” or “sore” in the oral cavity; it has a 5-year survival rate of over 80%, which drops to as low as 50% once lymph node involvement develops and to less than 30% with distant metastases. The overall 5-year survival rate is 61%, though in black men the survival rate is less than 40%, likely due to the presence of a more advanced stage of disease at time of diagnosis. Oral carcinoma metastasizes most commonly to ipsilateral cervical lymph nodes , but metastasis to the contralateral side— especially from primary lesions of the tongue or floor of the mouth—occurs frequently. The lungs are the most frequently involved extranodal metastatic site. Local recurrence is common. More than 50% have recur rence within 3 years. Many instances may actually represent new primary disease, suggesting a susceptibility of the entire oral mucosa to malignant change in affected patients. Those who have recurrence or progression within 6 months of plat inum-based chemotherapy have a median survival of less than 6 months. Treatment Surgery , radiation therapy (external beam and/or brachytherapy), and coadjuvant chemotherapy (e.g., cisplatin, carboplatin) encom pass the treatment options for oral cancer. One or a combina tion of modalities is utilized depending on the stage of disease, location, and the patient’s overall condition (nutritional status, comorbidities, willingness to undergo treatment). As noted, early-stage disease, occurring in about one third of patients, has a good prognosis; cure rates of 80% (stage I) and 65% (stage II) are reported. Surgical resection is the first line of therapy and the most effective. Radiotherapy is often added, given the radio sensitivity of squamous cell cancers and the risk of multifocality. A common dilemma is whether to conduct localized neck dissec tion (which entails additional treatment morbidity) for localized node-negative oral cancer. Randomized trial finds elective neck dissection achieves better outcomes than does waiting for recurrence to initiate neck dissection. Because the majority of these cancers are diagnosed in advanced stages of disease (III or IV), cure rates fall, as noted, to 30% and 5-year survival to less than 50%. Metastatic disease has a survival of about 4 months, especially when it becomes resistant to chemotherapy. In those with platinum-refractory disease, immunotherapy with nivolumab , a monoclonal anti body which blocks programmed death 1 (PD-1) and enhances immune response to tumor, has been shown to nearly double the rate of 1-year survival to 36%.

people with a lifestyle, occupational, or residential exposure to sun or other sources of ultraviolet A and B radiation . Pipe smoking also increases risk for cancer of the lip.

NATURAL HISTORY AND RESPONSE TO TREATMENT (1,4,8–11)

Asymptomatic dysplastic lesions typically precede the develop ment of oral cancer. The onset of pain, the symptom that most commonly leads patients to seek medical attention, usually indicates advanced disease. Since early disease is often asymp tomatic or easily overlooked, disease at time of diagnosis may be more advanced than if picked up by screening. Premalignant Disease The most important premalignant conditions to consider are leukoplakia, erythroplasia, and actinic cheilitis. Leukoplakia Leukoplakia—a potentially premalignant “white patch” on the oral mucosa—demonstrates dysplastic features on biopsy in 10% of cases. It can present either homogenously with uniform white appearance and flat surface or heterogeneously with a mixed red-white appearance and irregularly flat or nodular texture. It is difficult to differentiate completely benign from premalignant leukoplakia except by biopsy; however, patients demonstrat ing a speckled red-white pattern interspersed with areas of ulceration or erosion are more likely to have dysplastic disease. Lesions may occur anywhere on the oral mucosa, but those on the tongue have the greatest risk of malignant transformation. Such transformation may take anywhere from 1 to 20 years to occur. In addition to premalignant dysplasias and squamous cell carcinoma, the differential diagnosis of oral leukoplakia includes a host of additional conditions (see Table 211-1). Erythroplasia Erythroplasia—a red, hyperplastic area of mucosa—is highly suggestive of an early carcinoma. Although most cancer screen ing protocols have emphasized a search for white lesions, the predominant color in premalignant or early lesions is red, not white. In fact, whereas some white lesions may only be “premalignant,” the red lesions must be considered to be true malignancies unless proven otherwise by biopsy. Actinic Cheilitis Actinic cheilitis lesions are areas of dryness, scaliness, atro phy, ulceration, and color variation of the lips caused by solar

Table 211-1 Important Causes of Leukoplakia

Premalignant dysplasia Squamous cell carcinoma

SCREENING AND DIAGNOSTIC PROCEDURES (1,4,12,13) Traumatic irritation (from malposed teeth or ill-fitting dentures) Chemical irritation (typically from aspirin dissolved in the oral cavity) Viral infection (so-called hairy leukoplakia seen in HIV infection) Lichen planus Oral candidiasis Discoid lupus Pemphigus vulgaris Copyright © 2020 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. The challenge to primary care physicians is to recognize pre malignant and early malignant lesions of the oral cavity. The greatest hope for improved outcome is detection before the appearance of grossly invasive disease. The ready accessibility of the oral cavity to inspection and the appearance of premalig nant mucosal changes facilitate early detection. Incisional biopsy of suspicious lesions should follow.