Antineoplastics

Question 1

how do antineoplastic drugs work

Answer 1

• drugs treat various types of cancers or neoplasms: abnormally growing cells; also treated by surgery and/or radiation therapy
• work on neoplasms: may be benign or malignant (chance to metastasize)

Question 2

how does cancer chemotherapy work

Answer 2

• complex process
• use of chemical agents that act by different mechanisms
• cycles of treatment

Question 3

what do antineoplastics do

Answer 3

• kill cancer cells through damaging cell DNA or interfering with DNA synthesis
• toxic: affect normal cells -> high incidence of adverse events, toxicity and teratogenicity

Question 4

what are side effects of antineoplastics

Answer 4

• most common adverse side effects: nausea and vomiting
• other toxic effects: bone marrow suppression, leukopenia -> predisposes patients to serious infections and thrombocytopenia -> serious bleeding problems
• examples: cyclophosphamide, methotrexate, paxitaxel, bleomycin, tamoxifen

Question 5

what are cell cycle specific antineoplastic agents

Answer 5

• primarily affect cells that are actively multiplying

Question 6

what are cell-cyclic nonspecific agents

Answer 6

• kill cells that are actively multiplying or at rest

- more toxic to normal cells than the CCS agents, but good for slow-forming neoplasms

Question 7

what is a major cause of cancer treatment failure

Answer 7

• drug resistance, resulting in drugs that do not work on the cells

Question 8

how often are there dental complications with patients being treated with chemotherapy and all patients receiving radiation

Answer 8

• in about 40%

Question 9

how is xerostomia treated in patients with chemo

Answer 9

• due to suppression of salivary function, usually not permanent so treatment is usually palliative
• uncomfy because there is no salivary lubrication and the mucosal tissues get ‘sticky’ – dry mucosa may also be more prone to bleeding

Question 10

what are patients taking chemo more at risk for

Answer 10

• candidiasis and dental/root caries

Question 11

how can we prevent caries in patients taking chemo

Answer 11

• neutral sodium fluoride rinse such as prevident rinse

Question 12

what is mucositis

Answer 12

• stomatitis
• inflammation and ulceration
• small areas of the ulceration quickly become large areas due to the direct toxic effect of the antimetabolites
• difficult to prevent as well as treat: viscous lidocaine; chlorhexidine rinse

Question 13

what is oral candidiasis

Answer 13

• aka thrush
• common due to an overgrowth of fungi because of reduced white blood cell count
• it may be more important to prevent rather than treat
• anesthetic solution will help reduce the pain

Question 14

what are bacterial infections

Answer 14

• the primary concern with high bacteria levels is the increased incidence of bacteremia
• ## thus, the patient may be placed on antibiotics as a prophylaxis for effective endocarditis

Question 15

why are bacterial infections see more common in cancer patients

Answer 15

• seen due to bone marrow suppression, which reduces the white blood cell count

Question 16

how does chlorhexidine oral rinse help with cancer ptes

Answer 16

• reduce bacterial levels and helps with oral hygiene

Question 17

what causes taste alterations in cancer ptes

Answer 17

• alterations in taste are commonly seen in the cancer patient
• .this may occur due to the drug’s ability to affect sensitive taste buds

Question 18

what are limitations to dental tx for chemo ptes

Answer 18

• the majority of patients will have depressed white blood cells (neutrophils), which an increase the incidence of infections
• patients may also have low platelets, which may increase the incidence of bleeding
• antibiotics may be necessary when blood cell counts fall below 1500 mm3
• bleeding becomes significant when platelets fall below 100,000mm3
• there are some drug interactions with antineoplastic agents but there are not any dental drug interactions
• nausea and vomiting may be complication treatment of the patient

Question 19

what are immunosuppressant drugs

Answer 19

• used in patients after receiving an organ transplant from another human being to prevent rejection of the organ
• these drugs are usually given together with glococorticosteroids
• immunosuppressant drugs include azathioprine, cyclosporine, and tacrolimus
• patients taking immunosuppressants will most likely develop hypertension and subsequently will also be taking an antihypertensive drug such as a calcium channel blocker (eg nifedipine), which may also cause gingival enlargement
• pretransplant dentistry: critical part for the pmts, evaluate for the dental infections before placed on the ‘list’
• cyclosporine causes gingival enlargement
• patient taking this drug will be taking it forever
• gingival enlargement can be controlled by frequent gingivectomy/gingivoplasty procedures and meticulous home care
• drugs that alter cytochrome P450 isoenzymes in the liver may alter the plasma levels of the cyclosporine