Chemotherapy  Patients on hormone therapy whose tumors have progressed are candidates for cytotoxic chemotherapy.  There are no data suggesting that combination therapy results in an OS benefit over single-agent therapy.  Patients with hormone receptor-negative tumors and those with visceral metastases or symptomatic disease are also candidates for cytotoxic agents.  The selection of therapy in individual patients is influenced by the following:  Rate of disease progression. Presence or absence of comorbid medical conditions. Physician/patient preference.  Decisions regarding the duration of chemo. may consider the following: Patient preference and goals of treatment.  Presence of toxicities from previous therapies.  Availability of alternative treatment options.

Source:  NCI  2019