Long-term outcomes after an initial experience of computer-navigated resection of primary pelvic and sacral bone tumours: soft-tissue margins must be adequate to reduce local recurrences

Background
Short-term outcomes using navigated surgery reduced surgical time, blood loss, intralesional resection rate and preserved function.

Aims
We investigated the local recurrence rate at extended follow-up in patients following navigated resection of primary pelvic and sacral tumours.

Methods
This prospective cohort study comprised 23 consecutive patients between 2010
and 2012 undergoing primary pelvic and sacral tumour resection using computer navigation. Local recurrence (LR) and mortality rates were calculated
using the Kaplan-Meier method.

Results
Bone resection margins were all clear, with no bony recurrence. At a median
follow-up of 6.0 years, eight patients (34.8%) developed soft-tissue LR with an
overall cumulative LR rate at 6-years of 35.1% (95% CI=19.3-58.1%). Overall
cumulative all-cause mortality rate at 6-years was 26.1% (95% CI = 12.7%-
49.1%).

Conclusion
Despite the positive early experience with computer navigation-assisted resection LR rates remain high. With increasing knowledge of the size of soft tissue margins required to reduce LR and the close proximity of native structures in the pelvis, we advise against compromising resection to preserve function and encourage surgeons to reduce LR by prioritising wide tumour resection margins. Computer navigation remains a useful tool to aid pelvic tumour resection, but adequate soft tissue margins remain essential.