Chemotherapy Side Effects and Gene Expression

Study Notes

Taxanes are associated with hypersensitivity reactions, peripheral neuropathy, myalgias, and arthralgias for a few days following the infusion.
Cyclophosphamide is associated with hemorrhagic cystitis, myelosuppression, nausea/vomiting, and alopecia.
Alkylating agents are associated with a risk of secondary leukemia.

Gene expression assays (Oncotype DX and MammaPrint) can identify patients who could avoid chemotherapy without altering the disease prognosis.
Genomic analyses may play an important role in improving risk stratification and determining chemotherapy benefit.

Trastuzumab is indicated for treatment of breast cancer in patients who have tumors that overexpress HER-2.
Trastuzumab should not be given concurrently with the anthracyclines due to increased risk of cardiotoxicity.
Common adverse effects of trastuzumab include infusion-related reactions (e.g., chills).
Rare adverse effects of trastuzumab include pulmonary reactions (dyspnea, pulmonary infiltrates, non-cardiogenic pulmonary edema, and hypoxia).

Hormonal therapies studied in the treatment of early breast cancer include SERMs, oophorectomy, ovarian irradiation, LHRH agonists, and aromatase inhibitors (AIs).
Tamoxifen is a SERM that is anti-estrogenic in breast cancer cells but has estrogenic properties in other tissues and organs.
Administration of tamoxifen should begin after completion of chemotherapy.
Patients receiving tamoxifen should be counseled about warning signs of endometrial cancer and thromboembolism.

In premenopausal women, the use of LHRH agonists or other means of ovarian ablation have been shown beneficial in the adjuvant setting.
AIs are recommended as the endocrine therapy of choice for postmenopausal women.
Anastrozole and letrozole are non-steroidal compounds that exhibit reversible, competitive inhibition of aromatase.
Exemestane is a steroidal compound that binds irreversibly to aromatase, forming a covalent bond.

Treatment of stage III breast cancer generally consists of a combination of surgery, radiation, and systemic therapy administered in an aggressive approach with the treatment goal of a cure.
Systemic relapse and death are common.
Neo-adjuvant chemotherapy is used to render inoperable tumors resectable, even with the possibility of breast-conserving surgery.
Chemotherapy regimens used in stage III breast cancer are similar to those used in the adjuvant setting.