McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 1 4  Antineoplastic agents

CANCER CELL–SPECIFIC AGENTS bortezomib erlotinib everolimus

MISCELLANEOUS ANTINEOPLASTICS arsenic trioxide hydroxyurea

mitomycin mitoxantrone

anastrazole bicalutamide cabazitaxel degarelix exemestane flutamide fulvestrant

MITOTIC INHIBITORS docetaxel etoposide paclitaxel teniposide vinblastine vincristine vinorelbine

irinotecan topotecan tretinoin

gefitinib imatinib lapatinib nilotinib sorafenib sunitinib temsirolimus

goserelin letrozole

ANTINEOPLASTIC ADJUNCTIVE THERAPY

megestrol nilutamide tamoxifen toremifene triptorelin

amifostine leucovorin mesna rasburicase

HORMONES AND HORMONE MODULATORS abiraterone

T he use of the term chemotherapy implies cancer treat­ ment to most people. However, only one branch of chemotherapy involves drugs developed to act on and kill or alter human cells—the antineoplastic agents , which are designed to fight neoplasms , or cancers. Antineoplastic drugs alter human cells in a variety of ways. Their action is intended to target the abnormal cells that compose the neoplasm or cancer, having a greater impact on them than on normal cells. Unfortu­ nately, normal cells also are affected by antineoplastic agents. This area of pharmacology, which has grown tre­ mendously in recent years, now includes many drugs that act on or are part of the immune system. These substances fight the cancerous cells using components of the immune system instead of destroying cells directly (see Chapter 15). This chapter discusses the classic anti­ neoplastic agents and includes those drugs that are used in cancer chemotherapy. CANCER Cancer is a disease that can strike a person at any age and is one of the leading causes of death in Australia and New Zealand. Treatment of cancer can be pro­ longed and often debilitating. The person can experience numerous and wide-ranging complications and effects. All cancers start with a single cell that is geneti­ cally different from the other cells in the surrounding tissue. This cell divides, passing along its abnormalities to daughter cells, eventually producing a tumour or neoplasm that has characteristics quite different from those of the original tissue (see Figure 14.1). As the abnormal cells continue to divide, they lose more and more of their original cell characteristics. The cancerous cells exhibit anaplasia —a loss of cellular differentiation and organisation, which leads to a loss of their ability to

Cancer cells

Precancerous cells

Normal cells

FIGURE 14.1  Malignant tumours develop from one cell, with somatic mutations occurring during cell division as the tumour grows.

function normally. They also exhibit autonomy , growing without the usual homeostatic restrictions that regulate cell growth and control. This loss of control allows the cells to form a tumour. Over time, these neoplastic cells grow uncontrol­ lably, invading and damaging healthy tissue in the area and even undergoing metastasis , or travelling from the place of origin to develop new tumours in other areas of the body where conditions are favourable for cell growth (see Figure 14.2). The abnormal cells release enzymes that generate blood vessels ( angiogenesis ) in the area to supply both oxygen and nutrients to the cells, thus contributing to their growth. Overall, the cancer­ ous cells rob the host cells of energy and nutrients and block normal lymph and vascular vessels as the result of pressure and intrusion on normal cells, leading to a loss of normal cellular function. The body’s immune system can damage or destroy some neoplastic cells. T cells, which recognise the