Erratum to “Fractionated stereotactic body radiotherapy for up to five prostate cancer oligometastases: Interim outcomes of a prospective clinical trial”

The authors would like to correct an error in the reporting of one of the secondary outcomes—treatment escalation free survival (TE-FS)—in the originally published interim results of the TRANSFORM phase II trial.

This error affects N = 17 participants who were censored from the Kaplan-Meier analysis of TE-FS. In brief, the censor dates for these N = 17 participants erroneously defaulted to the data cut-off date for the interim analysis, rather than the true (earlier) date that these participants should have been considered censored.

Consequently, the originally reported median TE-FS of 27.1 months (95% CI 21.8-29.4) was 6 months longer than the true median length of TE-FS, 21.1 months (95% CI 18.3-26.9). Minor and insignificant differences in the subgroup analysis of TE-FS were found, with no change in the interpretation of these results. None of the other outcomes, including the primary outcome, were affected.

The authors sincerely apologise for this error.

The corrected text (top right-hand paragraph, page 164) is below:

• At the time of last follow-up, 105 patients had treatment escalation. The median TE-FS for the cohort was 21.1 months (95% CI 18.3-26.9 months). Increasing age (hazard ratio [HR] = 1.36, 95% CI 1.28-1.46, P < .001) was a statistically significant predictor for treatment escalation. Prior ADT (HR = 2.23, 95% CI 1.40-3.57, P = .001) but not concurrent ADT (HR = 1.49, 95% CI 0.75-2.96, P = .25) was also associated with poorer TE-FS compared to hormone naïve patients (Figure 1A). Patients with both bone and nodal lesions were at increased risk of treatment escalation compared to bone only (HR = 1.83, 95% CI 0.96-3.50, P = .066) (Figure 1B); however, the association was not statistically significant. There was no significant difference in TE-FS when comparing the node only and bone only groups (HR = 0.78, 95% CI 0.49-1.24, P = .296) or when comparing patients with 4-5 vs 1-3 initial lesions (HR = 1.11, 95% CI 0.71-1.73, P = .646) (Figure 1C).

Below is the corrected Figure 1A-D.

REFERENCE

Bowden P, See AW, Frydenberg M, et al. Fractionated stereotactic body radiotherapy for up to five prostate cancer oligometastases: interim outcomes of a prospective clinical trial. Int J Cancer. 2020;146:161-168. doi:10.1002/ijc.32509