106IN - If and When to Start Systemic Therapy As Palliation for People with Advanced Cancer

Abstract

ABSTRACT To benefit patients, treatment must improve either duration or quality of survival. For patients with minimal symptoms, one should only start palliative systemic treatment if there is strong evidence that (i) treatment improves the duration of survival, and (ii) that this effect will be lost if treatment is delayed until symptoms occur. You cannot make a well patient feel better but you can make them feel worse because of side-effects of treatment. If a patient is symptomatic, then treatment should be initiated provided that probability of benefit is greater than probability of increasing symptoms from effects of treatment. These principles will be illustrated by case scenarios of metastatic prostate and breast cancer. Androgen deprivation therapy (ADT) is not necessary for an asymptomatic man with slowly-rising PSA (doubling time >3 months) and low-volume metastatic prostate cancer. ADT has subtle but sometimes serious side effects. Often the main symptom is anxiety due to knowledge of PSA; this requires counselling rather than drug treatment. For symptomatic men or those with rapidly-rising PSA, ADT is effective palliation, and benefits of ADT have increased with availability of abiraterone and enzalutamide. For men with castrate-resistant prostate cancer similar principles apply to initiating chemotherapy with docetaxel. Chemotherapy generally has more side-effects than ADT, but can improve quality of life and prolong survival; however benefits are less and toxicity greater for men with comorbidity. Similar principles apply to treatment of metastatic breast cancer. In women with slowly-progressive non-visceral ER+ disease and minimal symptoms, hormonal therapy is usually appropriate. Chemotherapy should only be commenced to combat symptoms that cannot be treated by simpler means, including local radiotherapy. Women with triple negative or HER2+ve breast cancer have more rapid progression and are more likely to have visceral metastases: chemotherapy (+/-HER2 targeted therapy) can prevent or relieve symptoms but needs to be planned in relation to age and comorbidity. Performance status and patient-assessed quality of life are predictive of benefit from chemotherapy. Disclosure: The author has declared no conflicts of interest.