Oncologists Miscalculate Patient Survival

Oncologists may often provide imprecise survival estimates for patients with advanced cancer, according to a study published in JNCI Cancer Spectrum.

The oncologists studied “were equally likely to overestimate survival time as they were to underestimate it,” researchers reported.

For this study, the researchers pooled data from 1211 patients with advanced cancer who were enrolled in 7 prospective studies published between 2006 and 2022.

The patients’ median age was 66 (range, 16-92) years, and 61% were men. Cancer types included lung (40%), upper gastrointestinal (16%), colorectal (9%), breast (6%), and other (30%) cancers.

Overall, the median estimated survival time was 9 months, and the median observed survival time was 8 months.

The oncologists’ survival estimates met the definition of well-calibrated, as 50% of patients had an estimated survival time longer than their observed survival time.

The researchers noted that the calibration of oncologists’ estimates “did not vary greatly” according to the length of the estimated survival time. The exception was for patients with an estimated survival time exceeding 20 months. For these patients, 60% of estimated times were longer than the observed survival time.

The researchers also found that 28% of patients had a precise estimated survival time, which was defined as an estimate within 0.67 to 1.33 times the observed survival time. The precision of the oncologists’ estimates “did not very greatly” according to the length of the estimated survival time, the researchers noted.

Lastly, the researchers found that 8% of patients lived shorter than one-quarter of their oncologist’s estimate, 56% of patients lived within half to double their oncologist’s estimate, and 11% of patients lived longer than 3 times their oncologist’s estimate.

The researchers concluded that oncologists’ estimates “were well-calibrated but imprecise.” The researchers recommend that oncologists estimate a patient’s expected survival time (defined as the median survival time in a group of similar patients) and explain 3 scenarios for survival based on results provided by a free online tool the researchers developed.

Disclosures: One study author is a deputy editor of JNCI Cancer Spectrum. Please see the original reference for a full list of disclosures.

Reference

Nahm SH, Martin AJ, Clayton JM, et al. Accuracy of oncologists’ estimates of expected survival time in advanced cancer. JNCI Cancer Spectr. Published online November 14, 2023. doi:10.1093/jncics/pkad094

This article originally appeared on Cancer Therapy Advisor