Objectives
Cancer of Unknown Primary (CUP) is histologically-confirmed metastatic cancer with no primary site identified during diagnostic workup(1). Prognosis for patients with CUP is poor(2). The 2020 CUP Optimal Care Pathway (OCP) defined an approach to managing CUP(3). Our objective was to assess uptake of OCP recommendations and patient survival outcomes before and after OCP publication.
Sample and setting
Using South Australian Cancer Registry data, we identified adult patients treated for suspected or confirmed CUP at Flinders Medical Centre from 1 January 2010-31 December 2012 and 1 January 2020-31 December 2022.
Procedures
We reviewed case notes, electronic medical records and pharmacy records to extract data regarding demographics, investigations, treatments, and survival.
Results
52 patients were included for analysis (2010-12 n=33; 2020-22 n=19). Median age at diagnosis was 71 years (range 40-93); the majority (62%) were male. Median interval from referral to oncology specialist review was 15.5 days in 2010-12 and 19.0 days in 2020-22 (p=0.80, OCP target within 2 weeks). 93% of patients in 2010-12 and 95% in 2020-22 completed diagnostic workup within 2 weeks of specialist review (p=1.0). Proportion of patients discussed at a multi-disciplinary meeting was similar across cohorts (59% in 2010-12 vs. 63% in 2020-22, p=1.0). Proportion who had any PET scan or any molecular test rose over time (27% in 2010-12 vs. 53% in 2020-22 (p=0.08) and 3% vs. 21% (p=0.05), respectively). There was no difference in 24-month survival between cohorts (27.3% (95% CI 15.6-47.6) in 2010-12 vs. 26.3% (95% CI 12.4-55.8) in 2020-22, p=0.7).
Conclusion
Adherence to key OCP recommendations was similar pre- and post-OCP publication. Survival outcomes for CUP remain poor. Prospective research is ongoing.