Two-stage revision for infection of oncological megaprostheses

Aims The aim of this study was to assess the incidence of reinfection in patients after two-stage revision of an infected megaprosthesis (MPR) implanted after resection of a bone tumour. Methods A retrospective study was carried out of 186 patients from 16 bone sarcoma centres treated between January 2010 and December 2020.The median age at the time of tumour diagnosis was 26 years (IQR 17 to 33); 69 (37.1%) patients were female, and 117 (62.9%) were male. Results A total of 186 patients with chronic MPR infections were included. Median follow-up was 68 months (IQR 31 to 105).The most represented sites of MPR were distal femur in 93 cases (50.0%) and proximal tibia in 53 cases (28.5%). Polymicrobial infections were seen in 34 cases (18.3%).The most frequent isolated pathogens were staphylococci. Difficult-to-treat (DTT) pathogens were isolated in 50 cases (26.9%).The estimated infection recurrence (IR) rate was 39.1% at five years and 50.0% at ten years. A higher IR rate was found in DTT PJI compared to non-DTT infections (p = 0.019). Polymicrobial infections also showed a higher rate of infection recurrence (p = 0.046). Conclusion This study suggests that an infected MPR treated by two-stage revision and ultimately reimplantation with a MPR can be successful, but the surgeon must be aware of a high recurrence rate compared to those seen with infected conventional implants.