Revista de carcinogénesis y mutagénesis

Abstracto

Low-Dose Palliative Chemotherapy Compared to Standard-Dose Chemotherapy for Poor-Prognosis Cancers Improves Overall Survival - A Single Institution Retrospective Study

Andrew Dind, Rebecca Kannourakis, George Kannourakis, Jarmila Sterbova

Background: Palliative oncology is a balance between maximising quality and quantity of life. Whilst aggressive chemotherapy is associated with severe side effects, low-dose chemotherapy now plays a role in treating many advanced malignancies with palliative intent. There is a need to compare the survival of patients receiving low-dose with standard-dose chemotherapy.

Methods: Data collected from Ballarat Oncology and Haematology Services (BOHS) records was retrospectively assessed for patients diagnosed between 2004-2010 with advanced ovarian, lung, colorectal and pancreatic cancers. 166 patients were assessed for their chemotherapy doses, classed as low-dose chemotherapy (n=69) or standard-dose chemotherapy (n=97). Survival was assessed using the Kaplan-Meier method and the difference between the groups assessed using log rank tests with hazard ratios created using the Cox proportional hazards model.

Findings: Across all cancers, low-dose chemotherapy patients had a survival advantage (log rank=33•76, p<0•00001, HR 0•38, 95% CI 0•38-0•54, p<0•00001). There was a survival benefit for low-dose therapy in ovarian cancer (log rank=9•91, p=0•0016, HR 0•15, 95% CI 0•04-0•54, p=0•0047), pancreatic cancer (log rank=7•47, p=0•0063, HR 0•2, 95% CI 0•057-0•71, p<0•0001) and lung cancer (log rank=24•72, p<0•0001, HR 0•3, 95% CI 0•18-0•50, p<0•0001). There was no significant survival benefit for colorectal cancer patients receiving low-dose chemotherapy (log rank=1•16, p=0•28, HR 0•72, 95% CI 0•39-1•33, p=0•30), although there was a trend to improved survival.

Interpretation: Low-dose chemotherapy was associated with longer survival compared to standard doses of chemotherapy in this group. This novel study found a survival benefit with low dose chemotherapy in patients with advanced ovarian, pancreatic and lung cancers. However this study was not powered to find benefit in individual cancer groups. Large randomised controlled trials are required in order to adequately assess this effect without the presence of confounders.

Funding: This project was performed as a MBBS (Honours) project and as such did not have funding associated with it. RK and JS volunteered their time to the project to provide assistance, ensuring that data collected was accurate.