Temozolomide

INTRODUCTION

Indications

Refractory anaplastic astrocytoma progressing despite treatment with a nitrosourea and procarbazine. Glioblastoma multiforme (with or after radiation).

Action

Temozolomide is not active until converted at physiologic pH to 3-methyl-(triazen-1-yl)imidazole-4-carboxamide (MTIC), which alkylates DNA, disrupting its synthesis. Therapeutic Effects: Death of rapidly replicating cells, especially malignant ones, resulting in regression or slowed tumor growth.

Adverse Reactions/Side Effects

CNS: SEIZURES, fatigue, headache, abnormal coordination, anxiety, depression, dizziness, drowsiness, mental status changes, weakness. EENT: abnormal vision, diplopia. Resp: cough. CV: peripheral edema. GI: nausea, vomiting, abdominal pain, anorexia, constipation, diarrhea, dysphagia. Derm: pruritus, rash. Endo: adrenal hypercorticism. Hemat: leukopenia, thrombocytopenia, anemia. Metab: ↑ weight. MS: abnormal gait, back pain. Neuro: hemiparesis, myalgia. Misc: breast pain (women), fever, secondary malignancies (rare).

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Be alert for new seizures or increased seizure activity, especially at the onset of drug treatment. Document the number, duration, and severity of seizures, and report these findings to the physician or nursing staff immediately.

• Instruct patient to report signs of leukopenia (fever, sore throat, signs of infection), thrombocytopenia (bruising, nose bleeds, and bleeding gums), or unusual weakness and fatigue that might be due to anemia. Report these signs to the physician or nursing staff.

• Assess coordination problems, gait abnormalities, or hemiparesis that affects balance and functional activities. Report balance problems and functional limitations to the physician and nursing staff, and caution the patient and family/caregivers to guard against falls and trauma.

• Assess any back or muscle pain to rule out musculoskeletal pathology; that is, try to determine if pain is drug induced rather than caused by anatomic or biomechanical problems.

• Assess dizziness and drowsiness that might affect gait, balance, and other functional activities (See Appendix C). Report balance problems and functional limitations to the physician and nursing staff, and caution the patient and family/caregivers to guard against falls and trauma.

• Assess peripheral edema using girth measurements, volume displacement, and measurement of pitting edema (See Appendix N). Report increased swelling in feet and ankles or a sudden increase in body weight due to fluid retention.

• Monitor changes in mood or behavior such as anxiety, depression, or other alterations in mental status. Notify health care professional promptly if these symptoms develop.

• Monitor signs of increased adrenal cortex activity (adrenal hypercorticism). Signs include cushingoid appearance, including puffiness in the face (moon face), increased abdominal fat, thin arms and legs, abdominal skin striations, changes in skin pigmentation, bruising, and deposition of fat behind the base of the neck (buffalo hump). Report these signs to the physician or nursing staff.

• Periodically assess body weight and other anthropometric measures (body mass index, body composition). ...