Oncologists can give “remarkably accurate” estimates of survival time for women with ovarian cancer, Australian research shows.
Providing best case, worst case and typical scenarios for survival will allow clinicians to offer useful and accurate estimates to women with recurrent ovarian cancer, according to findings presented at ASCO 2019 in Chicago.
In a comparison of expected versus observed survival times for almost 900 women with ovarian cancer, NSW researchers found that oncologists’ estimates were imprecise but could be accurate when provided in terms of single multiples above and below the expected survival time.
Dr Felicia Roncoloto, a medical oncologist at the NHMRC Clinical Trails Centre, University of Sydney led the study into oncologists’ estimates of expected survival time for 898 women with recurrent ovarian cancer enrolled in the multinational GCIG study. Women had platinum resistant/refractory and potentially platinum sensitive (PPS) ovarian cancer and at least two lines of therapy.
Oncologists’ estimates were overall unbiased, in that 55% of women lived longer than their expected survival time. The results were defined as imprecise, since 23% of the women lived within 0.75 to 1.33 times their expected survival time.
But the scenarios for survival time based on oncologists’ estimates were remarkably accurate, as 7% of women died within one quarter of their expected survival time, 13% lived longer than three times their expected survival time, and 53% lived from half to double their expected survival time.
The median expected survival time for the overall group was 12 (3-70) months and the median observed survival time was 12.7months (CI 95% CI: 12-14%).
For women with platinum resistant refractory ovarian cancer the median expected survival time for the overall group was 12 (3-48) months and the median observed survival time was 11 months (CI 95% CI: 9-12%). For women with PPS ovarian cancer the survival rates were 12 (3-70) and 17 months (95% CI: 14-20) respectively.
Oncologists’ estimates of expected time were independently significant predictors of overall survival (HR 0.96, CI 0.94-0.98, p < 0.0001) in Cox models accounting for previously established prognostic factors.
The researchers noted that most with ovarian cancer have advanced disease at diagnosis, and more than 80% will experience recurrent disease despite treatment with doublet platinum-based chemotherapy.
Predicting, formulating and communicating prognosis for women with recurrent ovarian cancer was difficult, they said
“Best-case, worst-case and typical scenarios based on simple multiples of expected survival time were remarkably accurate, and provide a useful approach for predicting, formulating, and explaining prognosis in women with recurrent ovarian cancer,” they concluded.