Association Between Pathologic Chemotherapy Response Score and Pattern of Recurrence in Advanced High-Grade Serous Ovarian Cancer
Abstract
Background
Chemotherapy Response Score (CRS) is a three-tier histopathologic system evaluating response to neoadjuvant chemotherapy (NACT) in high-grade serous ovarian cancer (HGSOC).
Methods
We evaluated recurrence patterns and survival outcomes in advanced-stage HGSOC patients treated with NACT and interval debulking surgery (IDS) between 2015 and 2024.
Results
Among 238 patients, CRS3 was most frequent (43.3%) and was associated higher complete cytoreduction (CC0) rates (93%) compared to CRS2 (81%) and CRS1 (57%) (p < 0.001). Median follow-up was 35 months (IQR 12.6–42.2). Median progression-free survival (PFS) was 40.4 months for CRS3, 23.4 for CRS2, and 21.5 for CRS1 (p = 0.001). Among 109 (45.7%) patients who relapsed, 25 (23%) presented with oligometastatic disease (≤5 lesions), more frequently in CRS3 (46%) than CRS2 (8.9%) or CRS1 (15%) (p < 0.001). Specifically, peritoneal (p = 0.002) and nodal (p = 0.05) oligorecurrences were more common in the CRS3 group. CRS3 predicted oligometastatic recurrence (OR = 4.89; p = 0.008) and was associated with increased use of locoregional therapies (surgery or radiotherapy) at relapse (p = 0.014). Median overall survival (OS) was 93.9, 37.2, and 31.7 months for CRS3, CRS2, and CRS1, respectively (p < 0.001).
Conclusions
CRS3 predicts lower recurrence risk, increased rates of oligometastatic relapse, and greater use of locoregional treatments in patients with recurrent HGSOC after NACT and IDS.