Kumar A, et al. - The benefit of chemotherapy in the high-grade, serous subtype relative to the line of therapy was investigated using etoposide as the example. This retrospective study showed a similar degree of benefit from etoposide, as defined by the percentage remaining progression free at 3 months, in all lines of therapy.

Methods

• Researchers performed a retrospective review of women treated with oral etoposide at the British Columbia Cancer Agency upon recurrence/progression in the years 2000 to 2010.
• They used Kaplan-Meier and Cox regression methods to correlate line of therapy with overall survival, progression-free survival, and interval between etoposide initiation and next progression or death (EPFS).

Results

• Researchers reviewed a total of 219 women [median age 61].
• These women were administered etoposide as second (17%), third (30%), fourth (26%), fifth (17%), and sixth to eighth (11%) lines of therapy.
• They noted that the median number of cycles was 2 to 4.
• A significantly longer median overall survival and initial progression-free survival (from diagnosis to first relapse) was observed among patients who received etoposide as fourth-line to eighth-line treatment when compared with those who received it as second-line to third-line treatment (47.8 vs 25.8 mo, P < 0.0001; and 16.1 vs 12.1 mo, P < 0.0001, respectively); that is, a selected population of survivors received it later in the course of their disease.
• Univariate analysis revealed no significant difference in median EPFS (range, 2 to 2.9 mo) on the basis of line of therapy.
• Multivariate analysis showed that the hazard ratios improved through the third, fourth, and fifth lines (hazard ratios: 0.82, 0.77, and 0.34, respectively), and was statistically significant in the fifth line.
• In this study, the a priori-defined endpoint of clinical benefit was the “percentage not progressing at 3 months,” and this was achieved in 32% to 48%.