Cetuximab

INTRODUCTION

Indications

Locally or regionally advanced squamous cell carcinoma of the head and neck with radiation. Recurrent or metastatic squamous cell carcinoma of the head and neck progressing after platinum-based therapy. Epidermal growth factor receptor (EGFR)–expressing metastatic colorectal cancer in patients who have not responded to irinotecan and oxaliplatin. Metastatic colorectal cancer (with irinotecan) when tumors express EGFR and have not responded to or are intolerant of irinotecan alone.

Action

Binds specifically to EGFR, thereby preventing the binding of endogenous epidermal growth factor (EGF). This prevents cell growth and differentiation processes. Combination with irinotecan enhances antitumor effects of irinotecan. Therapeutic Effects: Decreased tumor growth and spread.

Adverse Reactions/Side Effects

Most adverse reactions reflect combination therapy with irinotecan CNS: malaise, depression, headache, insomnia. EENT: conjunctivitis. Resp: dyspnea, ↑ cough, interstitial lung disease. CV: PULMONARY EMBOLISM. GI: abdominal pain, constipation, diarrhea, nausea, vomiting, anorexia, stomatitis. GU: renal failure. Derm: acneform dermatitis, alopecia, nail disorder, pruritus, skin desquamation. F and E: dehydration, hypomagnesemia, peripheral edema. Hemat: anemia, leukopenia. MS: back pain. Metab: weight loss. Misc: INFUSION REACTIONS, fever, desquamation of mucosal epithelium.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Monitor signs of pulmonary embolism, including sudden shortness of breath, chest pain, cough, and bloody sputum. Notify physician immediately, and request objective tests (Doppler ultrasound, lung scan, others) if thromboembolism is suspected.

• Report allergy-like responses (wheezing, laryngeal edema, urticaria, other skin reactions) that occur during and after administration (infusion-related reactions).

• Assess any breathing problems or signs of interstitial lung disease such as dry cough, wheezing, chest pain, shortness of breath, and difficult or labored breathing. Monitor pulse oximetry and perform pulmonary function tests (See Appendices I, J, K) to quantify suspected changes in ventilation and respiratory function.

• Watch for signs of leukopenia (fever, sore throat, mucosal lesions, other signs of infection) and anemia (unusual fatigue, weakness, pallor). Report these signs to the physician immediately.

• Monitor signs of renal failure, including decreased urine output, increased blood pressure, muscle cramps/twitching, edema/weight gain from fluid retention, yellowish brown skin, and confusion that progresses to seizures and coma. Report these signs to the physician immediately.

• Watch for signs of low magnesium levels (hypomagnesemia), such as lethargy, irritability, insomnia, muscle tremors, and confusion. Notify physician of these signs.

• 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.

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

• Monitor ...