Block 10 Antineoplastic MCQ's Prt1

The correct answer is "It is highly lipid soluble and therefore can easily enter the brain." Carmustine is a chemotherapy drug that is commonly used to treat CNS neoplasms because it is highly lipid soluble. This means that it can easily cross the blood-brain barrier and enter the brain, where it can target and kill cancer cells. Its ability to penetrate the brain makes it an effective treatment option for tumors in the central nervous system.

Cyclophosphamide is known to cause hemorrhagic cystitis, which is characterized by bleeding and inflammation in the bladder. MESNA (2-mercaptoethane sulfonate) is a drug that is commonly used to counteract this specific adverse effect. It works by binding to and inactivating the toxic metabolites of cyclophosphamide that are responsible for causing bladder damage. By administering MESNA along with cyclophosphamide, the risk of developing hemorrhagic cystitis is reduced.

Rescue therapy is the concept that underlies the therapeutic strategy of giving leucovorin along with high dose methotrexate in the treatment of acute lymphoblastic leukemia. Methotrexate is a chemotherapy drug that works by inhibiting the growth of cancer cells, but it can also affect normal cells. Leucovorin is given to "rescue" the normal cells from the toxic effects of methotrexate by providing a source of folic acid, which is necessary for normal cell function. This allows for the selective targeting of cancer cells while minimizing damage to normal cells.

Bleomycin could have caused the pulmonary disorder in this patient. Bleomycin is known to cause pulmonary toxicity, which can present as dyspnea, cough, and infiltrates on chest x-ray. The lung biopsy findings of inflammation and fibrosis are consistent with bleomycin-induced lung injury. This adverse effect is dose-dependent and can occur at any time during treatment, but is more common with prolonged use. Other drugs in the regimen, such as cyclophosphamide, doxorubicin, vincristine, and prednisone, are not typically associated with this type of pulmonary toxicity.

Dactinomycin binds to double-stranded DNA, which inhibits the process of DNA transcription. This means that it prevents the DNA from being used as a template to produce RNA, which is an essential step in protein synthesis. By inhibiting DNA transcription, dactinomycin interferes with the ability of cancer cells to replicate and divide, ultimately leading to cell death. This mechanism of action is particularly effective against rapidly dividing cells, such as those found in Wilms' tumor.

The patient is most likely to suffer from nausea and vomiting during the first day of treatment with the given combination chemotherapeutic regimen. Chemotherapy drugs such as cyclophosphamide, vincristine, doxorubicin, and prednisone are known to cause gastrointestinal side effects, including nausea and vomiting, in many patients. These side effects are commonly experienced shortly after starting chemotherapy and can be managed with antiemetic medications.

Cisplatin is a platinum-based chemotherapy drug that is known to cause kidney damage. The elevated levels of creatinine and BUN suggest impaired kidney function, which is a common side effect of cisplatin. Additionally, the low level of magnesium in the plasma is also consistent with cisplatin-induced kidney damage, as the kidneys play a role in maintaining magnesium levels in the body. Therefore, cisplatin is the most likely drug to have caused these laboratory abnormalities.

Doxorubicin is the most likely drug that has caused the findings described. Doxorubicin is known to have cardiotoxic effects, which can lead to tachycardia, shortness of breath, neck vein distension, pulmonary rales, and ankle edema. These symptoms are consistent with congestive heart failure, which can be a side effect of doxorubicin treatment. The other drugs listed do not typically cause these specific symptoms.

Cisplatin is a chemotherapy drug known to cause ototoxicity, which can manifest as tinnitus and hearing loss. The symptoms of tinnitus and hearing loss in the 10-year-old boy are likely caused by cisplatin, as it is a known side effect of this specific drug.

Doxorubicin is a chemotherapy drug that works by intercalating between DNA strands and inhibiting topoisomerase II. Topoisomerase II is an enzyme that helps to unwind and separate DNA strands during replication and transcription. By inhibiting this enzyme, doxorubicin prevents DNA from being properly replicated and transcribed, leading to cell death. This mechanism of action is particularly effective against rapidly dividing cancer cells, as they rely heavily on DNA replication and transcription for their growth and survival.

Cyclophosphamide is a chemotherapy drug that can cause bladder irritation and inflammation, leading to symptoms such as hematuria (blood in the urine) and pain during urination. These symptoms are consistent with the child's presentation. Prednisone is a corticosteroid and does not typically cause these urinary symptoms. Vincristine, cisplatin, and doxorubicin are other chemotherapy drugs that can have various side effects, but they are not typically associated with hematuria and pain during urination.

The most likely drugs included in the woman's combination chemotherapy regimen are cisplatin and paclitaxel. These drugs are commonly used in the treatment of ovarian carcinoma. Cisplatin is a platinum-based chemotherapy drug that works by damaging the DNA of cancer cells, preventing their replication and growth. Paclitaxel is a taxane chemotherapy drug that works by disrupting the microtubules in cancer cells, inhibiting their division and growth. The combination of these drugs is often used to target different aspects of cancer cell growth and increase the effectiveness of treatment.

Chlorambucil is an alkylating agent, which means it forms covalent bonds with nucleophile groups on DNA bases. This leads to the cross-linking of DNA strands and prevents their separation and replication. By interfering with DNA structure and function, chlorambucil inhibits the growth and division of cancer cells, ultimately leading to their death.

The patient's presentation, including fatigue, malaise, and nosebleeds, along with the findings of normochromic, normocytic anemia and lymphoblasts in the blood and bone marrow, are consistent with acute lymphoblastic leukemia (ALL). Vincristine and prednisone are commonly used in the induction phase of treatment for ALL. Vincristine is a vinca alkaloid that disrupts cell division, while prednisone is a corticosteroid that helps to kill lymphoblasts. Therefore, Vincristine and prednisone are the most likely drugs included in the therapeutic management of this boy.

Granulocytes are a type of white blood cell that includes neutrophils, eosinophils, and basophils. They are responsible for fighting infections and are highly sensitive to chemotherapy drugs. Therefore, it is expected that the granulocytes will decrease first in this patient as a result of the chemotherapy treatment. Lymphocytes, monocytes, platelets, and erythrocytes may also be affected by chemotherapy, but the granulocytes are typically the most sensitive and will decrease first.