Breast Cancer Palliative Treatment

Introduction
This section covers palliative therapy of disseminated disease incurable by surgery (stage IV).

Radiotherapy
Palliative radiotherapy may be advised for primary treatment of locally advanced cancers with distant metastases to control ulceration, pain, and other manifestations in the breast and regional nodes. Irradiation of the breast and chest wall and the axillary, internal mammary, and supraclavicular nodes should be undertaken in an attempt to cure locally advanced and inoperable lesions when there is no evidence of distant metastases. A small number of patients in this group are cured in spite of extensive breast and regional node involvement.

Palliative irradiation is of value also in the treatment of certain bone or soft tissue metastases to control pain or avoid fracture. Radiotherapy is especially useful in the treatment of isolated bony metastasis, chest wall recurrences, brain metastases, and acute spinal cord compression.

Hormone & Targeted Therapy
Disseminated disease may shrink - or grow less rapidly - after endocrine therapy such as administration of hormones (eg, estrogens, androgens, progestins; see Table 17-5); ablation of the ovaries, adrenals, or pituitary; or administration of drugs that block hormone receptor sites (eg, antiestrogens) or drugs that block the synthesis of hormones (eg, aromatase inhibitors). Hormonal manipulation is usually more successful in postmenopausal women even if they have received estrogen replacement therapy. Treatment should be based on the presence of estrogen receptor protein in the primary tumor or metastases. The rate of response is nearly equal in premenopausal and postmenopausal women with ER-positive tumors. A favorable response to hormonal manipulation occurs in about one-third of patients with metastatic breast cancer. Of those whose tumors contain estrogen receptors, the response is about 60% and perhaps as high as 80% for patients whose tumors contain progesterone receptors as well. Because only 5-10% of women whose tumors do not contain estrogen receptors respond, they should not receive hormonal therapy except in unusual circumstances, eg, in an older patient who cannot tolerate chemotherapy. Because the quality of life during a remission induced by endocrine manipulation is often superior to a remission following cytotoxic chemotherapy, it is usually best to try endocrine manipulation first in cases in which the estrogen receptor status is unknown. Additionally, women with ER-positive tumors who fail hormone therapy or experience progression should be placed on a different form of hormonal manipulation. Women who have failed tamoxifen and gone on to a third-generation aromatase inhibitor have shown equal if not better response than those who respond to tamoxifen. When receptor status is unknown but the disease is progressing rapidly or involves visceral organs, however, endocrine therapy is rarely successful, and introducing it may waste valuable time.