Oral cancer medical therapy

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Sargun Singh Walia M.B.B.S.[2], Simrat Sarai, M.D. [3]; Grammar Reviewer: Natalie Harpenau, B.S.[4]

Overview[edit | edit source]

The predominant therapy for oral cancer is surgical resection, radiation therapy or a combination of both. Adjunctive chemotherapy, radiation, chemotherapy may be required. Radiation in the form of external-beam radiation therapy (EBRT) or interstitial implantation is used. Advantages of radiotherapy are that normal anatomy or function are maintained and general anesthesia is not needed. Disadvantages of radiotherapy are that it is inefficient to treat large tumors, subsequent surgery is more difficult, oral mucositis, dry mouth (xerostomia), osteoradionecrosis (ORN), etc.

Medical Therapy[edit | edit source]

• Depending on the site and extent of the primary tumor and the status of the lymph nodes, some general considerations for the treatment of lip and oral cavity cancer include the following:
  • Surgery alone
  • Radiation therapy alone
  • A combination of the above

Radiation[edit | edit source]

• External-beam radiation therapy (EBRT) or interstitial implantation can be administered to give radiation therapy for lip and oral cavity cancers.
  • These can be used alone; whereas, combined use of both modalities produce better control and functional results at some sites.
  • Implants of iridium Ir 192 are often used.
• Small, superficial cancers are treated by local implantation using intra-oral cone radiation therapy or by radiation using electrons.
• Larger lesions are managed using EBRT to include the primary site and regional lymph nodes, even if they are not clinically involved.
• interstitial radiation is used to supplement therapy to achieve adequate doses to treat large primary tumors and/or bulky nodal metastases.^[1]
• A review of published clinical results of radical radiation therapy for head and neck cancer suggests a significant loss of local control when the administration of radiation therapy was prolonged; therefore, lengthening of standard treatment schedules should be avoided whenever possible.^[2]

Advantages of radiotherapy[edit | edit source]

• Normal anatomy and function are maintained
• General anesthesia is not needed

Disadvantages of radiotherapy[edit | edit source]

• More adverse effects
• Not efficient to treat large tumors
• Subsequent surgery is more difficult and hazardous and survival is reduced further
• dry mouth
• Difficulty swallowing
• weight loss

• Short-term complications
  • Oral mucositis
    • 40% of patients are affected
    • Can be so severe that treatment has to be stopped sometimes
• Long-term complications
  • Dry mouth (xerostomia)
  • Loss of taste
  • Osteoradionecrosis (ORN)

Treatment of early cancers {stage I and stage II}[edit | edit source]

• Stage I and II cancer of the lip, floor of the mouth, and retromolar trigone can be treated by surgery or radiation therapy.^[3]
• The choice of treatment is decided based on functional and cosmetic results.
• buccal mucosa carcinoma can be treated by radiation therapy.
• T1 and T2 stage cancer of the anterior tongue may be treated radiation therapy alone.
• Radiation therapy has 85% cure rates in early lesions.
• Benefits of using radiation therapy over surgical resection are:
  • Lesser chances of speech disabilities
  • Less chance of aspiration of liquids and solid.
• Cancer involving upper-gingiva or hard palate without bone involvement can be treated by radiation therapy alone.
• Patients who smoke while on radiation therapy appear to have lower response rates and a shorter survival duration than those who do not; therefore, patients should be counseled to stop smoking before beginning radiation therapy.^[4]

Treatment of advanced cancers{stage III and stage IV}[edit | edit source]

• Most patients with stage III or stage IV tumors are candidates for treatment by a combination of surgery and radiation therapy.
• Patients with small T3 lesions,no regional lymph nodes, and no distant metastases (or patients who have no lymph nodes larger than 2 cm in diameter) can be treated by radiation therapy alone.
• Because local recurrence and/or distant metastases are common in this group of patients, they should be considered for clinical trials that are evaluating the following:
  • The potential role of radiation modifiers are to improve local control or decrease morbidity.
  • The role of combinations of chemotherapy with surgery and/or radiation therapy are to both to improve local control and decrease the frequency of distant metastases.

Surgery[edit | edit source]

• For lesions of the oral cavity, surgery must adequately encompass all of the gross, as well as the presumed microscopic extent of the disease.^[5]
  • If regional nodes are positive, cervical node dissection is usually done in continuity.
  • Surgeons ablate large posterior oral cavity tumors using reconstructive methods so that satisfactory functional results can be achieved.
  • Prosthodontic rehabilitation is important, particularly in early-stage cancers, to assure the best quality of life.

References[edit | edit source]

Template:WH Template:WS