Paclitaxel Health Dictionary

A group of CYTOTOXIC drugs administered intravenously for the treatment of advanced ovarian cancer (see OVARIES, DISEASES OF) and secondary spread of breast cancer (see BREASTS, DISEASES OF). Given under specialist supervision in hospital, taxanes are not e?ective for all patients but results are encouraging when they do respond. Side-effects include HYPERSENSITIVITY, MYELOSUPPRESSION, cardiac ARRHYTHMIA, and peripheral NEUROPATHY. Examples of the taxanes are PACLITAXEL and DOCETAXEL.... taxanes

Cytotoxic means destructive to living cells. Cytotoxic drugs possess anti-cancer properties but also have the potential to damage normal tissue. Their use is twofold: to eliminate a cancer and so prolong life; or to alleviate distressing symptoms, especially in patients whose prospects of a cure are poor. In many cases CHEMOTHERAPY with cytotoxic drugs is combined with surgery, RADIOTHERAPY or both. Chemotherapy may be used initially to reduce the size of the primary TUMOUR (a process called neoadjuvant therapy) before using radiotherapy or surgery to eliminate it. Cytotoxic drugs may also be used as adjuvant treatment to prevent or destroy secondary spread of the primary tumour that has either been removed by surgery or treated with radiotherapy. All chemotherapy causes side-effects: the ONCOLOGIST – a specialist in cancer treatment – has to strike a balance between hoped-for bene?ts and acceptable (for the patient) toxic effects, which include nausea and vomiting, BONE MARROW suppression, ALOPECIA (hair loss) and teratogenic effects (see TERATOGENESIS).

Cytotoxic drugs are used either singly or in combination, when an enhanced response is the aim. Chemotherapy of cancer is a complex process and should be supervised by an oncologist in co-operation with physicians, surgeons, radiotherapists and radiologists as appropriate.

The cytotoxic drugs include:

(1) The alkylating agents which act by damaging DNA, thus interfering with cell reproduction. Cyclophosphamide, ifosfamide, chlorambucil, kelphalan, busulphan, thiotepa and mustine are examples of alkylating agents.

(2) There are a number of cytotoxic antibiotics used in the treatment of cancer – doxorubicin, bleomycin, dactinomycin, mithramycin and amsacrine are examples. They are used primarily in the treatment of acute leukaemia and lymphomas.

(3) Antimetabolites – these drugs combine irreversibly with vital enzyme systems of the cell and hence prevent normal cell division. Methotrexate, cytarabine, ?uorouracil, mercaptopurine and azathioprine are examples.

(4) Another group of cytotoxic drugs are the vinca alkaloids such as vincristine, vinblastine and vindesima.

(5) Platinum compounds such as carboplatin, cisplatin and oxaliplatin are e?ective. All of them are given intravenously, but the latter two tend to have more unpleasant side-effects. Carboplatin and cisplatin are useful in the treatment of solid tumours. Carboplatin, a derivative of cisplatin, is given intravenously in ovarian cancer and in small-cell lung cancer. Better tolerated than cisplatin, the drug causes less nausea and vomiting, nephrotoxicity, neurotoxicity and ototoxicity. Where platinum-containing therapy has failed, intravenous treatment with paclitaxel may be tried. With only a limited success rate, it is relatively toxic and should be carefully supervised; responses, however, are sometimes prolonged.

Also of increasing importance in treating cancer are interferons. These are naturally occurring proteins with complex effects on immunity and cell function. Although toxic, with numerous adverse effects, they have shown some anti-tumour e?ect against certain lymphomas and solid tumours.... cytotoxic

A member of the group of antitumour drugs known as TAXANES, docetaxel is used to treat advanced or metastatic cancer arising in the breast (see BREASTS, DISEASES OF). It is also used to treat non-small cancer of the LUNGS. The NATIONAL INSTITUTE FOR CLINICAL EXCELLENCE (NICE) has recommended that both docetaxel and PACLITAXEL should be available for the treatment of advanced breast cancer where initial anticancer CHEMOTHERAPY (including one of the ANTHRACYCLINES) has failed or is inappropriate.... docetaxel

Oöphoritis (infection of the ovaries) rarely occurs alone, except in viral infections such as mumps. Usually it is associated with infection of the FALLOPIAN TUBES (SALPINGITIS). It may occur as a complication of a miscarriage, a therapeutic abortion, or the birth of a baby. Cases not associated with pregnancy typically result from sexual activity: the most common organisms involved are Chlamydia, E. coli, and Neisseria gonorrhoea. Cervical swabs should be sent for culture and analgesics given, together with the appropriate antibiotics.

Failure of OVULATION is the cause of INFERTILITY in around a third of couples seeking help with conception. It may also lead to menstrual problems (see MENSTRUATION), such as an irregular menstrual cycle or MENORRHAGIA. An uncommon cause of failure of ovulation is POLYCYSTIC OVARY SYNDROME, often associated with acne, hirsutism, and obesity. Treatment depends on the symptoms. Early ovarian failure is the cause of premature MENOPAUSE. Treatment consists of hormone replacement therapy using a combination of oestrogen and progestogen.

Ovarian cysts (for example, follicular cysts) result from ovulation. They may be symptomless but sometimes cause abdominal pain, pain during intercourse or disturbances in menstruation. Twisting or rupture can cause severe pain, pyrexia (fever) and nausea, and explorative surgery – endoscopic laparotomy – may be needed to establish a diagnosis (symptoms of ECTOPIC PREGNANCY are similar). The ovary may have to be removed. Simple cysts often disappear of their own accord but a large cyst can cause pressure on surrounding structures and therefore should be surgically removed.

In young women the most common benign tumour is a dermoid cyst, while in older women, ?broma (see under UTERUS, DISEASES OF) is more common. All benign tumours should be removed surgically in order to be sure they are not malignant.

Malignant tumours may be primary (arising in the ovary) or secondary (metastases from a cancer developing in another organ). Treatment depends upon the site and type of the primary tumour.

Around 5,000 women a year are diagnosed as having ovarian cancer in England and Wales. Unfortunately it is not readily detected in its early stages; around 85 per cent of women do not see a doctor until after the tumour has spread. Early tumours present with symptoms similar to benign tumours, while late ones present with abdominal distension, pain and vague gastrointestinal symptoms. The disease is most common in menopausal women. Earlier diagnosis and treatment can be achieved by ULTRASOUND screening. Treatment is surgical, aimed at totally removing the tumour mass. Nowadays RADIOTHERAPY is only used for palliation. CHEMOTHERAPY is often given to patients with ovarian metastases, or who have residual disease after surgery. The most active cytotoxic agent is the taxane, PACLITAXEL – especially when it is combined with cisplatin.... ovaries, diseases of

n. any of a group of *cytotoxic drugs formerly extracted from a species of yew tree (Taxus) but now synthesized or produced by biotechnological methods. These drugs interact with tubulin, a protein involved in cell division, and have been found to exercise control on the growth of certain cancers, particularly breast and ovarian tumours. Taxanes include *docetaxel and *paclitaxel.... taxane

n. see paclitaxel.... taxol