Platinum resistance after neoadjuvant chemotherapy compared to primary surgery in patients with advanced epithelial...

Primary debulking surgery (PDS) has historically been the standard treatment for advanced ovarian cancer. Recent data appear to support a paradigm shift toward neoadjuvant chemotherapy with interval debulking surgery (NACT-IDS) for a subset of women with advanced ovarian cancer. It remains unresolved whether NACT-IDS increases the risk of platinum resistance. We compared response to chemotherapy in patients that received NACT-IDS vs. PDS.

From our Cancer Registry database we identified patients with stages IIIC and IV epithelial ovarian cancer who underwent treatment from January, 2005 to December, 2010. Standard univariate analyses were performed, as were multivariable analysis with logistic regression. The Kaplan-Meier method was used to generate survival data.

The study population consisted of 425 patients, 95 (22.3%) underwent NACT-IDS and 330 (77.6%) PDS. After the initial platinum-based chemotherapy, 42 (44.2%) women in the NACT-IDS group were considered to have platinum resistant disease, compared to 103 (31.2%) in the PDS group (P=0.01). When multivariate logistic regression was used to control for factors independently associated with platinum resistance, NACT-IDS was no longer associated with an initial increased risk. However, in women that had a recurrence and were retreated with platinum-based chemotherapy, 32 (88.8%) in the NACT-IDS group had developed a recurrence within six months and were considered platinum resistant, compared to 62 (55.3%) in the PDS (P<0.001).

In women with EOC that have a recurrence and are treated again with platinum-based chemotherapy, NACT-IDS appears to increase the risk of platinum resistance.