Factors correlating with shorter survival after treatment: aiding oncologists to choose who (not) to receive palliative systemic therapy

Abstract

BACKGROUND: A rising number of metastatic cancer patients are receiving palliativesystemic therapy close to end of life. Patients started on such treatment are typically judged by oncologists to have ≤ 12 weeks survival, but accurate survival prediction is difficult on individual patients. Systemic therapy started too late may not benefit patient, but rather, adversely affect patient’s quality of life and may even shorten survival due to treatment side effects. Our study objective is to identify factors correlating with a shorter ( ≤ 6 weeks) non-malignancy related survival in metastatic cancer patients receiving palliative systemic therapy, so as to aid oncologist in the decision-making of starting treatment or not. METHODS: A review of deceased adult metastatic cancer patients treated with palliative systemic therapy from January 2013 to December 2014 in our cancer center in Hong Kong was carried out. They were subcategorized into dying within or after 6 weeks since starting their last line of palliative systemic therapy, and also by their cause of death (malignancy-related or non-malignancy related). Univariable analyses were carried out to determine associations of different variables with non-malignancy related death that happened within 6 weeks of starting their last line of palliative systemic treatment. Multivariable analyses were carried out with significant factors in univariable analyses to determine their independent effect. RESULTS: Seven hundred and fifty-four patients were analyzed. Mean age was 63.6 years old (range 21-102); female 48.7%. Older age ( ≥ 75 years) (p = 0.007) and active liver metastasis (p = 0.042) were significant predictors for early ( ≤ 6 weeks) non-malignancy related death in multivariable analysis. They have 2.012 times and 1.115 times higher chance respectively to die of non-malignant causes within 6 weeks since the start of their last line of palliative systemictreatment. CONCLUSIONS: Oncologists should exercise extra caution when encountering elderly patients with active liver metastasis, especially with regard to the issue of starting palliative systemic therapy.