Many malignant lesions have their predecessors. The status of any lesion, whether benign or malignant, can only be confirmed by histologic examination. The American Cancer Society guidelines suggest that lesions which have an unknown source and that fail to heal within two weeks undergo biopsy. Unfortunately, patients may dismiss lesions which are asymptomatic as harmless. Yet squamous cell carcinoma, the most frequent oral malignancy, can appear in various shapes, sizes, locations, and colors. Despite this pleomorphism, certain lesions have a higher potential for malignant transformation.
Erythroplakic (red) lesions and leukoplakic (white) lesions can occur anywhere within the oral cavity. While the erythroplakic lesions occur less frequently, a higher proportion are found to be dysplastic. Some even have carcinoma in situ. Dysplasia refers to atypical cell formation and/or arrangement, while carcinoma in situ features dysplastic cells which are limited to one tissue layer only and no further infiltration.
Without medical intervention, this single layer will usually form a malignant lesion capable of metastasis. Most cancers including oral cancer are rarely diagnosed at this early stage.
A premalignant lesion which commonly affects the lower lip is Actinic Cheilitis. These lesions can be localized or diffuse. The ultraviolet component of solar radiation has been identified as a risk factor, but is not the only cause. Initial damage is done in the subepithelial connective tissues. Elastic fibers are irreversibly damaged. This precedes swelling, disintegration, and the formation of an acellular matrix of material. The anatomic manifestation of this process is thickened skin which can blur the usually distinct border between the skin and the vermillion junction of the lip. Hyperkeratosis, with or without cellular dysplasia, may occur. There is a moderate to high chance of squamous cell carcinoma development in these lesions. Individuals with fair complexions and less melanin have a higher incidence of actinic cheilitis. Melanin has the protective feature of absorbing ultraviolet radiation.
Biopsies of areas of actinic cheilitis are needed as the clinical appearance cannot be correlated with a malignant or benign condition. An ulcerated tissue surface may not indicate a malignant transformation while smooth tissue surface may not be benign.
Surgically, a vermillionectomy procedure is performed. Tissue is excised to a depth of 2-3 mm. inferior to and parallel to the vemillion border of the lip. A continuous incision into the commissures and labial vestibules produces a tissue section for histopathologic examination.
Lichen planus is usually a white, but sometimes a red and white lesion which accounts for approximately 9% of all leukoplakic lesions. he classic presentation is multiple papules which coalesce to form striae. Involvement of the buccal mucosa, tongue, and gingiva are the most common sites. There is no cure for these lesions with treatment being palliative. Studies have shown that the malignant transformation for these lesions is 2.3-3.0%. An erosive form of lichen planus can cause severe pain. There is a higher potential for malignant transformation with this erosive form. Although the potential for squamous cell carcinoma arising from both forms of these lesions is low, they must be monitored carefully.
Red lesions within the mouth, which are not secondary to any other disease process, are called erythroplakias. These are uncommon lesions especially when compared to their leukoplakic counterparts. Increased vascularity accounts for their red appearance and a tendency for easy bleeding. Biopsy of these lesions may reveal cellular dysplasia, carcinoma in situ, or even invasive carcinoma more frequently than leukoplakic lesions.
Some lesions may be ulcerated or elevated above the mucosal surface. DESPITE THEIR RARITY, THEIR MALIGNANT POTENTIAL SHOULD CAUSE ANY SUCH LESION TO BE BIOPSIED IF IT DOES NOT HEAL WITHIN A TWO WEEK PERIOD. Differential diagnosis by histological examination is needed to distinguish a potential malignancy from erosive forms of lichen planus or candidiasis, autoimmune lesions, viral lesions, or lesions of some sexually transmitted diseases.
External Beam radiation therapy (radiotherapy) is an adjunctive treatment for the postsurgical cancer patient. Clusters of malignant cells which may remain after the removal of the primary tumor are destroyed with this procedure.
A radiation oncologist will plan the treatment type and dosage of radiation to be used. High-energy (megavoltage) is used as this type of radiation does not gain full strength until it has attained some depth into the tissue. The part of the body through which the radiation beam will be directed is called the radiation port and is outlined in semipermanent ink. The tumor size, type, location, and stage will determine the total radiation dosage which will be tumorcidal. Since this dosage is very high, the total dosage is divided into a daily dose (fractionated) which will be tumorcidal and which will minimze the negative side effects.
The current dosage of radiation is measured in units called the Gray (Gy). One Gray equals 100 rads, so one cGy is equal to one rad of dosage. A cumulative dosage of 5,000-7,000 cGy (50-70 Gy) is fractionated over a five to seven week period. One treatment per day is given five days per week. Unfortunately, dosages above 4,500 cGy are usually associated with deleterious side effects to healthy tissue. Most oral cancers are treated with a cumulative dosage which exceeds this amount.
The damage which radiotherapy causes both malignant cells and normal cells is by direct action with the DNA molecule. Indirectly, ionizing radiation can react with water or oxygen molecules within the tissue. The reactive metabolites formed are called hydroxyl (OH) and superoxide (H2O2) free radicals. These compounds can then react with the DNA molecule and cause damage which prevents further cellular replication.
Effects of Radiotherapy
Tumors which originate within the oral cavity, nasopharynx, and head and neck are removed surgically. After a healing period of two to three weeks, external beam radiation (radiotherapy) is utilized to destroy remaining cancer cells that have strayed from the primary lesion.
The postsurgical course of radiotherapy usually involves five treatments per week for a period of five to seven weeks. Unfortunately, the tumorcidal doses of ionizing radiation can have deleterious effects upon the adjacent healthy tissues.
The most common side effect of radiotherapy is mucositis. The cells which comprise the basal layer of the oral epithelium have a high degree of mitotic activity which is similar to actively dividing malignant cells. The cells which comprise the surface layer of the oral mucosa originate from the basal layer. Ionizing radiation interrupts the proper mitotic sequence at the basal epithelium with the result that the cellsof the surface layer are not replenished. The cells of the mucosal tissues are four layers deep with an average turnover of three days. Thus, mucositis is not apparent for nearly ten days after the initiation of radiotherapy.
Mucositis: Clinical Manifestations
The interruption of cellular replication and the renewal of surface cells is observed as areas of blanching, erythema, or denuded patches which can be extremely painful. At times, radiotherapy must be discontinued while the lesions heal.
Fortunately, once radiotherapy stops, the tissues will heal and cellular renewal will begin anew. During therapy, the patient can do many things to ameliorate the symptoms. A soft, bland, but nutritionally balanced diet must be maintained. Surgical treatment may have produced areas which have not yet healed completely.
Swallowing solids may prove very difficult for these patients. Numerous liquid nutritional supplements can be utilized successfully in these situations. Any food which has sharp edges and which has the potential to lacerate tissue which is already inflamed should be avoided. Foods which are hot, spicy, and acidic should also be avoided. Alcoholic beverages and mouth rinses that contain alcohol should not be consumed or used, as the dehydrating effect of alcohol can exacerbate the pain of mucositis. Tartar control toothpaste can cause tissue sloughing even in healthy mucosa and should not be used.
Pain can be severe with patches of mucosal tissues denuded and erythemic. Ice water rinses, topical anesthetics such as viscous lidocaine and newer modalities such as sucralfate can provide temporary relief. Sucralfate, in suspension form, is sucrose in an aluminum base. This compound was originally designed to treat duodenal ulcers and can help relieve mucositis by the development of an insulating film over affected areas.
Salivary Gland Atrophy
The cells that comprise the salivary glands are highly susceptible to ionizing radiation. The tissues of the parotid glands are very radiosensitive. The acinar cells, which actually produce saliva, and the adjacent vascular tissues are both damaged. Tumor location and the angle and degree of irradiation can produce different degrees of damage. Radiotherapy for tumors within the nasopharynx produces permanent and irreversible damage to all major salivary and minor salivary glands. The resultant decrease in salivary flow is known as xerostomia. Unfortunately, most radiotherapy treatment produces varying degrees of xerostomia. Previous levels of salivary production are never fully realized again.
The composition of saliva is adversely affected. A decrease in the bicarbonate ion production causes a decrease in salivary pH with a proportionate increase in salivary acidity. The decreased volume of saliva, coupled with an increase in salivary pH, can have deleterious effects on the dentition. The self-cleansing action of saliva is reduced to a minimum. Plaque has a greater tendency to adhere to tooth surfaces and gingival tissues. An increase in caries and periodontal disease can ensue. The immunoglobulin content within the saliva markedly decreases. The oral microflora increases in the population of Streptococcus mutans, the bacterium most associated with dental caries.
Collectively, these factors can contribute to a serious and rapid form of decay known as radiation caries. Decay on the cusp tips, smooth surfaces, and the cementoenamel junction can produce decay so destructive that the teeth may need endodontic treatment or extraction. Dental consultation prior to the initiation of radiotherapy is essential. Instruction in oral hygiene and nutritional counseling can decrease the risk of radiation caries. Custom trays in which fluoride gels can be placed can be utilized on a daily basis to strengthen exposed tooth structure which is subject to demineralizaton.
The decreased lubricating function of saliva can be problematic for those patients who wear removable prostheses. An increase in tissue dryness predisposes the oral mucosa to ulcerations. Dentures and partials may be difficult to wear. Mastication and deglutition can become an extraordinarily difficult task at a time when the demands of the postsurgical and radiotherapy phase mandate appropriate nutrtion. Liquid nutritional supplements are needed during these times when the prostheses cannot be worn. Saliva substitutes can help and can be purchased over-the-counter. Cholinergic medications that stimulate salivary flow may be prescribed, but salivary flow rarely returns to preradiotherapy levels.
The radiotherapy-induced complication with the greatest severity is osteoradionecrosis. The exposure of necrotic bone through ulcerated mucosal tissue has a mean incidence of 10-15% among radiotherapy patients. Ionizing radiation produces a hyalinization among the vasculature with a corresponding decrease in blood perfusion. The resultant hypoxia causes necrosis to the affected osseous sites. The mandible has a higher incidence of osteoradionecrosis compared to the maxillary arch. The maxilla and premaxilla contain bone which is less compact and has a better vascular supply than does the mandible. Predisposing factors include a higher total dosage of radiotherapy, an immunocompromised status, tissue irritation, and malnutrition. Treatment is conservative since more than 50% of these cases resolve spontaneously. Gentle debridement with sterile saline solution and gentle removal of bony sequestra which do not exfoliate by themselves should be the extent of interceptive treatment. Since these areas are avascular, systemic antibiotics lack the hematogenous route for efficacy. Topical antibiotics can have a better, local effect. Hygiene must be maintained meticulously. The use of Chlorhexidine (0.12%) as an antimicrobial mouth rinse is an excellent adjunct as this compound has the ability to adhere to hard and soft tissues after rinsing. Patients who wear complete or partial dentures may need frequent adjustments, soft-tissue liners, or may need to refrain from their use until healing occurs. A nutritional diet must be maintained to provide the resources for healing.
Miscellaneous Effects of Radiotherapy
Most patients experience some degree of loss of the sensation of taste during radiotherapy. he decreased volume and increased viscosity of saliva decreases the ability of all foods to be appropriately dissolved in a salivary medium. The sensation of taste is usually restored, in part, after the cessation of radiotherapy.
The muscles, tendons, and ligaments that aid in mastication and movement of the temporomandibular joint can become fibrotic. Jaw movements can be difficult and even painful during functional excursions. Physical therapy can decrease the progressive damage of fibrosis.
Many of the oral complications associated with chemotherapy and radiotherapy can be minimized with a complete clinical and radiographic dental examination before any cancer treatment starts. Any tooth with necrotic pulpal tissue should be evaluated for endodontic therapy or extraction. Teeth with a poor prognosis periodontally should be extracted. Patients undergoing chemotherapy can have a decreased immune response due to myelosuppression. Infections of endodontic or periodontal origin can become very serious in such patients. Treatment to eliminate this pathosis can only be done when the lymphocyte numbers are restored to appropriate levels, and only upon clearance from the oncologist. Teeth that can be restored should be saved with restorations promoting excellent hygiene. Patients must receive instructions for oral hygiene and nutritional counseling. A diet that promotes appropriate nutrition for post-surgical healing without providing a cariogenic substrate for the oral microflora should be developed. Custom trays for fluoride application should be made preoperatively. The daily application of fluoride gels can decrease the incidence and severity of radiation caries. Any teeth with sharp edges should be smoothed to avoid the potential laceration of tissues inflamed by mucositis.
Edentulous patients should receive a complete soft-tissue examination and a panographic radiograph. Impacted teeth or residual roots can be detected and removed prior to active cancer treatment. Any tooth which needs to be extracted should be extracted at least three weeks before cancer surgery. After surgery is completed, patients should have the fit of their prostheses evaluated. Extensive soft-tissue and osseous resection may require the fabrication of new prostheses by an oral and maxillofacial prosthodontist. Patients should be encouraged to report any areas of ulceration promptly as these areas can become infected easily when chemotherapeutic agents induce myelosuppression. Patients should understand that the pain accompanying mucositis can make prosthesis retention difficult. There may be periods of time when complete or partial dentures cannot be worn. The inability to masticate properly, especially for those with complete dentures, would require the use of liquid nutritional supplements. Tissue changes may require relining or remaking the prostheses.
If emergency treatment such as endodontics or oral surgery is needed during chemotherapy or radiotherapy, prophylactic antibiotic coverage may be needed. Any invasive procedure should be cleared by the oncologist.
Oral Effects of Chemotherapy
Approximately half of the patients diagnosed with malignant disease require chemotherapy or radiation therapy. Chemotherapeutic drugs interfere with the replication of malignant cells by interaction with their nuclei. Unfortunately, this is a nonspecific cytotoxic effect which can affect the nuclei of the cells of normal tissue. Deleterious side effects can occur in any organ of the body. The following are those which present in and around the oral cavity.
The normal range for platelet production is between 150,000 and 400,000/mm3. Chemotherapeutic agents can cause a severe suppression of the hemopoietic cells of the bone marrow. The platelet production can drop below the minimal surgical therapeutic quantity of 50,000/mm3. Petechiae on the oral mucosa can be the first sign of thrombocytopenia. Platelet quantity and quality can both be adversely affected. Patients with a higher degree of periodontal pocketing can experience spontaneous bleeding episodes with clots that are poorly formed. Patients should refrain from elective dental treatment until the platelet count returns to normal levels as substantiated by laboratory analysis. Emergency treatment such as extractions performed during chemotherapy may need to be done in a hospital setting for the establishment of hemostasis.
nfections which can easily be controlled by antibiotic therapy in patients withcompetent immune systems can become life-threatening in the immunocompromisedcancer patient. The stem cells within the bone marrow which normally mature intogranular and agranular leukocytes can be severely depleted by the cytotoxic effect of chemotherapy. Phagocytic activity, B-Lymphocyte antibody production, and impairment of the lymphocytic response during the inflammatory reaction are all decreased. This can be a great concern systemically as opportunistic infections cause about 50% of deaths in the overall cancer population. Most infections are of fungal origin, usually with candida albicans. Oral infection with the herpes simplex virus, gram-negative bacilli, and gram-negative cocci can also occur.
The type of cancer and it’s treatment can influence the emergence and progression of infection. Leukemic patients receive more potent chemotherapy than do patients with solid tumors and have proportionately more myelosuppression and more problems with opportunistic infections. Infections within the oral cavity can be a portal for systemic dissemination, therefore they must be treated quickly and aggressively with antibiotics. Fungal infections are a special concern as their fatality rate once disseminated is double that of disseminated bacterial infections.
Viral infections can also plague the myelosuppressed patient. Infections with herpes simplex virus and herpes zoster (varicella zoster virus) are among the most common. The lesions of HSV infection cover much more mucosa than lesions seen in otherwise healthy patients. There is intense pain with these lesions and secondary infection is possible. Mastication and normal excursions of the jaw can be very difficult. Nutrition may be via liquid supplements. Chlorhexidine (0.12%) may be used as an adjunct for oral hygiene, however the alcohol content may irritate the herpetic lesions. Lesions of herpes zoster can cover large areas of tissue which is innervated by the trigeminal nerve. These lesions can last for weeks or months before resolution and are extremely painful for their duration. Acyclovir administered orally or applied as a cream can decrease the duration of both types of herpetic lesons.
The basal epithelium of the oral mucosa is adversely affected by the nonspecific cytotoxic effect of chemotherapy. The mucositis seen with radiotherapy for malignant lesions which originate within the oral cavity is due to the location of the primary lesion. The histological pattern of mucositis from either modality of therapy is similar. An important consideration is that many systemic cancers are treated with chemotherapy and mucositis can develop from their treatment. Clinicians should advise patients of these potential oral complications even though a completely different organ system may be the source of the malignant lesion. The clinical presentation of mucositis secondary to chemotherapy can range from focal erythema to large areas of desquamated, painful mucosa. his range can vary with the type of malignancy and the type and duration of chemotherapy.
Treatment is similar to that for mucositis induced by radiotherapy. However, the potential for secondary infection is greater here as chemotherapy also causes immuno-suppression. The combination of ulcerated mucosa and a decreased immune response can lead to a potentially fatal septicemia.
Some chemotherapeutic agents such as vincristine sulfate are more apt to cause neuropathies than others. Cranial nerve involvement occurs infrequently, but oral manifestations from affected trigeminal, facial, and glossopharyngeal nerves are those usually involved. Symptoms include paresthesia, pain of odontogenic or periodontal origin. Neural involvement of the facial nerve, the great motor nerve of the many facial muscles, can manifest as weakness of these muscles.
Clinical Classifications of Carcinomas
Standard international rules have been designed for the staging of carcinomas with the TMN system utilized. The size of the primary tumor and the degree of infiltration of the lip or oral cavity is indicated by the letter “T.” The evaluation can range from “TX,” ( the primary tumor cannot be evaluated ) to “T3,” ( the primary tumor has a size of 4 cm or larger at it’s greatest diameter.) The designation of “T4” indicates that a primary tumor of the lip or oral cavity has infiltrated muscular or osseous components.
Involvement of lymph nodes is designated by “N.” An evaluation of “NX” indicates that the regional lymph nodes cannot be evaluated. No metastasis to the regional lymph nodes is indicated by the “NO” designation. If bilateral lymph node involvement beyond 6 cm from the primary tumor is noted, the “N3” designation is used. The letter “M” is assigned for the categorization of metastasis. If metastasis cannot be evaluated, “MX” is utilized. The absence of distant metastasis is indicated by “MO,” while it’s presence is indicated by “M1.” These individual categories are combined into a stage grouping tumor formula. The stages are assigned numerical values of 0-4 which reflect the progressive nature of malignant disease. A “Stage 0” formula would be TisNOMO. This would indicate a primary lesion with only carcinoma in situ and without lymph node involvement or metastasis. A “Stage 4” lesion can be a composite of a T4 with or without metastasis and with or without lymph node involvement.
Higher numbers indicate a more progressive malignancy with a proportionately poorer prognosis. Unfortunately, many patients with oral cancer do not present for treatment at a point when the numbers associated with a minimally advanced malignancy are present. The five-year survival rate of 54% for oral cancers reflects this trend.
Squamous Cell Carcinoma
The oral malignancy which presents as the most aggressive lesion and which is responsible for over 90% of all oral malignancies is squamous cell carcinoma. The epithelium of the oral mucosa is composed of a flat, outer layer of cells called squamous cells. The transformation from healthy cells to dysplastic cells, and ultimately to carcinoma in situ, may take many years. Once malignant transformation occurs, nests of malignant cells descend through the basement membrane and infiltrate the underlying connective tissue. Early metastasis through the rich lymphatic and vascular supply in the floor of the mouth and the ventrolateral surface of the tongue can make the prognosis for the patient very poor. Early diagnosis and treatment are essential if a favorable prognosis is desired.
Oral cancers, as with all cancers, can be multifactorial in origin. However, a common thread among oral cancer patients is that 90% have used tobacco products habitually. Among these, cigarettes are the most common. Many patients within this group also consume alcoholic beverages on a regular basis. These dual habits can have a negative synergistic effect. The dehydrating nature of alcohol can desiccate the oral mucosa and cause a prolonged exposure to the carcinogens within tobacco products. Years of this repeated practice have proven to increase the risk of the development of oral cancer.
Prolonged mucosal trauma such as seen with poorly fitting dentures can produce chronically inflamed tissue which may undergo malignant transformation. Many long-term denture patients will experience occasional ulcerative sore spots that can be resolved by adjustments done by the dentist. Some patients assume chronic sore spots are a normal response to wearing prostheses and may not realize that areas which fail to heal may be a malignancy. Edentulous patients should report any sore spots that do not heal after the corresponding portion of the prosthesis has been adjusted professionally.
There are instances in which squamous cell carcinoma has developed in the absence of known risk factors. Regardless of the etiology, this carcinoma usually strikes people beyond the age of 45 and is twice as prevalent in men than women.
Sites of Occurrence
Squamous cell carcinoma can occur anywhere in the oral cavity, however, there is a predilection for some sites over others. The ventral and lateral surfaces of the tongue account for nearly half of the reported cases of squamous cell carcinomas. he dorsum of the tongue is rarely involved. The initial stages of malignancy are usually asymptomatic and difficult to visualize. Once symptoms such as pain, dsyphagia, paresthesia, or tumor size prompts the patient to seek medical attention, metastasis has usually occurred. The actual muscular contractions of the tongue during function are a major factor in the metastasis of malignant cells to adjacent lymph nodes and to distant sites. The prominent vascular supply to the tongue and the floor of the mouth affords excellent access for metastasis.
The floor of the mouth represents the site for about 15% of this malignancy. The tongue can easily prevent direct vision of this area. The alveolar mucosa, palate, and buccal mucosa follow in the frequency of occurrence.
There is no uniformity or consistency among the clinical features of squamous cell lesions. Any suspect lesion should be biopsied, especially if known risk factors are present and the lesion has remained unhealed for two weeks.
Treatment and Prognosis
Most squamous cell lesions are discovered at an advanced stage, so the treatment is usually more invasive and the prognosis less favorable. Surgery is the primary modality of treatment. Larger lesions within the oral cavity and oropharnyx may require radiotherapy preoperatively to shrink the lesion and to facilitate surgery. Radiotherapy postoperatively will be a reflection of tumor size and lymph node involvement. Chemotherapy is usually not used as an adjunctive treatment for squamous cell lesions.
Patients can face many challenges during the postoperative phase. Larger lesions, which require radical resection of mucosa, muscular and osseous tissue, can completely alter a patient’s life. Speaking, eating, and swallowing can be forever changed especially if the removal of the malignancy has caused nerve damage. Speech and physical therapy can be required to restore these functions to the patient, some of which may never return to their former levels. The patient should be emotionally and psychologically prepared for cosmetic alterations from surgery and for the lasting effects of radiotherapy.
A recall protocol is established with the surgeon or oncologist to assess the soft tissues for any recurrence of the primary lesion. Chest radiographs may be taken on an annual basis to evaluate the lungs for evidence of metastasis from the primary oral lesion.
Counseling for smoking cessation should be offered, as some patients will continue this habit postsurgically. Nutritional assessments may be needed as some patients must use stomach tubes for feeding as swallowing food is a function forever lost.
Basal Cell Carcinoma
This malignant lesion develops on the exposed surfaces of the skin, face, and scalp usually of persons middle-aged and beyond. Usually people of fairer complexion with less melanin pigmentation are at a higher risk of basal cell development. The head and the neck account for the location of nearly 90% of all of these lesions.60 The lips and the skin which surround them can be involved. Basal cell carcinomas grow slowly and metastasize infrequently. Growth of such lesions will continue until surgical excision.
The clinical presentation of a basal cell carcinoma is much more consistent, especially when compared to the pleomorphic squamous cell carcinoma. A centrally ulcerated area is surrounded by a rolled border. The latter represents malignant cells infiltrating laterally beneath the tissue. The central area of ulceration can bleed and form a scab, but does not heal. People may dismiss these lesions since they are usually small and painless. Basal cell carcinomas rarely originate within the oral cavity. However, a basal cell lesion, which starts on the skin and is not removed, can perforate into the oral cavity by direct extension.
The ultraviolet radiation of the sun is the predominant factor in the development of basal cell lesions. Repetitive mechanical, thermal, or chemical irritation can also cause their development. A cigarette, held in the same position for many years, is such an example.
Treatment and Prognosis
The treatment for basal cell carcinomas is surgical excision with radiation used as adjunctive treatment for larger lesions. Most people can see these lesions easily and seek medical attention promptly so the prognosis is usually excellent. Patients must be advised to minimize exposure to sunlight and/or discontinue the habit which has caused a long-term chronic irritation. Recall appointments should be made to examine the area for recurrence and for the emergence of new lesions.
Kaposi’s sarcoma is a malignancy associated with the terminal phases of HIV infection. Prior to the discovery of the causative agent of HIV infection and the course of the disease process itself, Kaposi’s sarcoma was extremely rare in the United States. This is a vascular malignancy which can occur anywhere in the body with oral manifestations common. This disease may reflect the oncogenic potential of the AIDS virus. The color of the lesions are red, purple, or brown. They may not blanch with the application of pressure. The hard palate is the most common site of occurrence although any intraoral tissue may be affected.
Treatment and Prognosis
Smaller lesions of Kaposi’s sarcoma are usually left untreated unless they interfere with comfort or function. Larger lesions in the oropharynx may compromise breathing and need surgical removal. A preoperative assessment must be made of the platelet count as patients in this stage of HIV infection have depressed bone marrow function. Since the CD4+ lymphocyte count is usually low at this phase, opportunistic postsurgical infection is always a risk. Some lesions may be treated with radiation, electrosurgery, laser therapy, or cryotherapy to decrease these risks. Radiotherapy may cause an intense mucositis with all of the side effects inherent with this treatment modality. Such tissue can be extremely painful and subject to opportunistic infection due to the decreased immune competence.
The prognosis once Kaposi’s sarcoma appears is poor. The numbers of those patients with HIV infection have increased since the discovery of this disease in the early 1980s. Despite many public health efforts to educate the public, many people still engage in behaviors that place them at risk of contracting HIV infection. Many individuals who are HIV seropositive are unaware of their status and are infectious to others when high risk behaviors are practiced. Such events will only increase the number of patients seropositive for HIV infection. Many of these will develop lesions of Kaposi’s Sarcoma.
Most dental treatment of patients at this phase of HIV infection will be limited to emergency treatment. Clearance from the primary care physician should be obtained even before emergency treatment as problems with bleeding and immunocompetence could be detrimental to the patient’s health.
Miscellaneous Neoplasms of the Oral Cavity
While squamous cell and basal cell carcinomas are the primary malignant lesions which originate within and around the oral cavity, any structure in this area can undergo malignant transformation.
Approximately 80% of neoplasms of salivary gland origin are initiated in the parotid glands. The remaining tumors are distributed among the submandibular, sublingual, and minor salivary glands.
The pleomorphic adenoma is the most common tumor of all the salivary glands. The lesion is derived from the epithelial and glandular components of the salivary gland. This is usually a benign lesion, but malignant transformation is possible. Orally, these lesions appear as firm, painless growths. Surgically, complete removal is required to minimize the chance for a recurrence. Any lesion which affects the parotid gland could put pressure on the facial nerve which courses through part of this gland. The muscles supplied by this large motor nerve may exhibit weakness and/or paresthesia. Swelling and tissue distention of the skin and tissues which overlie the parotid gland may also occur.
The aggressive malignant melanoma, whether as a primary or metastatic secondary lesion, may be seen orally. This malignancy of epidermal melanocytes is among the most deadly of all cancers. Lesions colored blue, purple, brown, or black, which may be flat or nodular, usually are seen on the palate or maxillary gingiva. Similar lesions are usually seen on the skin. Treatment can be a combination of surgery, radiotherapy, and chemotherapy with the prognosis usually poor.
Since tobacco usage has been identified as a high risk factor in the development of oral cancer, many public health programs and educational programs attempt to prevent teenagers from starting this habit. Smokeless tobacco is popular among young people and may be perceived as a product whose usage has no carcinogenic potential. This group must be educated that the contrary is true. Many older adults who have smoked for decades will find it difficult to stop. With this group within our population living longer and continuing their smoking habits, oral cancer will be a health problem that will continue. All patients should receive comprehensive soft tissue exams as part of dental examinations. Patients must be educated and motivated to seek early treatment for suspicious lesions and for symptoms within the oral cavity and oropharynx which do not disappear. Patients and clinicians should understand that oral cancer can still affect those in whom no major risk factors are identified. That which will never change is that early diagnosis and the corresponding treatment will increase the chances for a favorable prognosis.
Great strides have been made in the treatment of various cancers. Despite this, the five-year survival rate for oral cancers has not improved as have all other major cancers. Late diagnosis and subsequent metastasis usually leave oral cancer patients with an advanced malignancy that can be difficult to treat. Radiation therapy can leave a patient very weak and with permanent damage to the salivary glands. Surgery can remove the tumor, but the patient may be faced with a lifetime of functional problems and cosmetic disfigurement.
Dental professionals have a unique opportunity for screening patients for premalignant and malignant lesions. Those patients who are edentulous, especially those who use tobacco products, should promptly report non-healing denture sore spots. All patients who use tobacco products should receive information on the various medications and programs which offer an opportunity for those who want to eliminate this habit.
Patients that have been diagnosed with oral cancer should receive a complete dental exam prior to the initiation of surgery and radiotherapy. The extraction of periodontally borderline or hopeless teeth, treatment of necrotic pulps with endodontics or extractions, nutritional counseling, and the fabrication of custom trays for fluoride application will minimize emergency problems developing postoperatively. Clinicians should develop and maintain excellent diagnostic skills so that early identification and treatment of oral malignancies gives the patient the best prognosis possible.