Chapter 081. Principles of Cancer Treatment (Part 23)

Mucositis Irritation and inflammation of the mucous membranes particularly afflicting the oral and anal mucosa, but potentially involving the gastrointestinal tract, may accompany cytotoxic chemotherapy. Mucositis is due to damage to the proliferating cells at the base of the mucosal squamous epithelia or in the intestinal crypts. Topical therapies, including anesthetics and barrier-creating preparations, may provide symptomatic relief in mild cases. Palifermin or keratinocyte growth factor, a member of the fibroblast growth factor family, is effective in preventing severe mucositis in the setting of high-dose chemotherapy with stem celltransplantation for hematologic malignancies. It may also prevent mucositis from radiation....
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Chapter 081. Principles of Cancer Treatment (Part 23) Chapter 081. Principles of Cancer Treatment (Part 23) Mucositis Irritation and inflammation of the mucous membranes particularly afflictingthe oral and anal mucosa, but potentially involving the gastrointestinal tract, mayaccompany cytotoxic chemotherapy. Mucositis is due to damage to theproliferating cells at the base of the mucosal squamous epithelia or in the intestinalcrypts. Topical therapies, including anesthetics and barrier-creating preparations,may provide symptomatic relief in mild cases. Palifermin or keratinocyte growthfactor, a member of the fibroblast growth factor family, is effective in preventingsevere mucositis in the setting of high-dose chemotherapy with stem celltransplantation for hematologic malignancies. It may also prevent mucositis fromradiation. Alopecia Chemotherapeutic agents vary widely in causing alopecia, withanthracyclines, alkylating agents, and topoisomerase inhibitors reliably causingnear-total alopecia when given at therapeutic doses. Antimetabolites are morevariably associated with alopecia. Psychological support and the use of cosmeticresources are to be encouraged, and chemo caps that reduce scalp temperature todecrease the degree of alopecia should be discouraged, particularly duringtreatment with curative intent of neoplasms such as leukemia or lymphoma, or inadjuvant breast cancer therapy. The richly vascularized scalp can certainly harbormicrometastatic or disseminated disease. Gonadal Dysfunction and Pregnancy Cessation of ovulation and azoospermia reliably result from alkylatingagent– and topoisomerase poison–containing regimens. The duration of theseeffects varies with age and sex. Males treated for Hodgkins disease withmechlorethamine- and procarbazine-containing regimens are effectively sterile,whereas fertility usually returns after regimens that include cisplatin, vinblastine,or etoposide and after bleomycin for testicular cancer. Sperm banking beforetreatment may be considered to support patients likely to be sterilized bytreatment. Females experience amenorrhea with anovulation after alkylating agenttherapy; they are likely to recover normal menses if treatment is completed beforeage 30 but unlikely to recover menses after age 35. Even those who regain mensesusually experience premature menopause. As the magnitude and extent ofdecreased fertility can be difficult to predict, patients should be counseled tomaintain effective contraception, preferably by barrier means, during and aftertherapy. Resumption of efforts to conceive should be considered in the context ofthe patients likely prognosis. Hormone replacement therapy should be undertakenin women who do not have a hormonally responsive tumor. For those patients whohave had a hormone-sensitive tumor primarily treated by a local modality,conventional practice would counsel against hormone replacement, but this issueis under investigation. Chemotherapy agents have variable effects on the success of pregnancy(Chap. 7). All agents tend to have increased risk of adverse outcomes whenadministered during the first trimester, and strategies to delay chemotherapy, ifpossible, until after this milestone should be considered if the pregnancy is tocontinue to term. Patients in their second or third trimester can be treated withmost regimens for the common neoplasms afflicting women in their childbearingyears, with the exception of antimetabolites, particularly antifolates, which havenotable teratogenic or fetotoxic effects throughout pregnancy. The need foranticancer chemotherapy per se is infrequently a clear basis to recommendtermination of a concurrent pregnancy, although each treatment strategy in thiscircumstance must be tailored to the individual needs of the patient. Chroniceffects of cancer treatment are reviewed in Chap. e13. Biologic Therapy The goal of biologic therapy is to manipulate the host-tumor interaction infavor of the host. Theoretically, biologic approaches should reflect a bell-shapeddose-response curve where the maximum biologic effect is less than the MTD.However, empirical trial and error has led to the discovery that a number ofbiologic treatment approaches may produce antitumor effects, but nearly all ofthem are most active at their MTD. As a class, biologic therapies may bedistinguished from molecularly targeted agents in that many biologic therapiesrequire an active response (e.g., reexpression of silenced genes, or antigenexpression) on the part of the tumor cell or on the part of the host (e.g.,immunologic effects) to allow therapeutic effect. This may be contrasted with themore narrowly defined antiproliferative or apoptotic response tha ...