Adjuvant chemotherapy for the "oldest old" ovarian cancer patients: can we anticipate toxicity-related treatment failure in a vulnerable population?

Background: Patients aged > or = 80 years who are diagnosed with advanced ovarian cancer (OC) have been reported to have a poor prognosis. In the current study, chemotherapy-related toxicity data were evaluated between patients aged > or = 80 years and those aged < 80 years.

Methods: Patients with OC who underwent cytoreductive surgery with chemotherapy were included. Self-reported toxicity data were obtained from National Cancer Institute Common Toxicity Criteria (CTC) forms. Objective indicators of status including albumin level, weight, and creatinine clearance were abstracted both before and after therapy. Data were compared between patients by decade of age.

Results: A total of 246 patients were included. A presenting Karnofsky performance status >2 was recorded in 17% of patients aged > or = 80 years versus 0% to 4% of patients aged < 80 years (P = .002). Platinum-based chemotherapy was used in all patients. For patients aged < 80 years, combination chemotherapy was used in > 90% versus 69% in those aged > or = 80 years (P < .0001). Standard-dose combination therapy was used in 72% to 86% of patients aged <80 years versus 28% of patients aged > or =80 years (P < .0001). Patients aged > or =80 years completed > or =6 cycles of therapy approximately 57% of the time versus 84% to 97% of the time for those aged < 80 years (P = .0001). CTC forms identified no self-reported toxicities to be more common among patients aged > or =80 years. Multivariate logistic regression identified creatinine clearance < 65 mL/minute (odds ratio [OR] of 4.6), 5% weight loss (OR of 2.5), prechemotherapy albumin level of < 2 g/dL (OR of 3.65), and initiation of therapy with a single agent (OR of 3.9) as independent predictors of failure to complete chemotherapy.

Conclusions: Despite initial treatment modifications as well as toxicity assessment, only 57% of patients aged > or =80 years completed planned chemotherapy. It was confirmed that further studies into the pharmacokinetics of chemotherapy in the elderly and more sensitive assessment of therapy-related toxicity are required.