Surgery, but not chemo, may benefit patients with rare ovarian neoplasms

Good quality surgery conferred a progression-free survival (PFS) benefit for women with ovarian sex cord stromal tumours (SCST) in the first-line setting and on first and second relapse. Chemotherapy, on the other hand, had no impact on survival in the first-line or relapse setting.

 

These were the main findings from the multicentre SALOMÉ study developed by the TMRG/GINECO group, which assessed the impact of surgery and chemo on ovarian SCST.

 

On multivariate analysis of PFS2, prognostic factors were peritoneal relapse (hazard ratio [HR], 3.34; p=0.003), surgery (HR, 0.37; p=0.009), and quality of surgery (HR, 3.19; p=0.004). The significant effect with surgery (HR, 0.34; p<0.001) and quality of surgery (HR, 3.57; p=0.025) were also evident on univariate analysis of PFS3. [ESMO Sarcoma and Rare Cancers 2023, abstract 13O]

 

These imply that performing a complete surgery improves PFS, noted Dr Helene Vanacker from the Centre Léon Bérard, Lyon, France, at ESMO Sarcoma and Rare Cancers 2023.

 

However, adjuvant chemo for FIGO* stage IC/II disease did not appear to deliver a PFS1 benefit (HR, 1.14; p=0.7), nor did perioperative chemo for PFS2 (HR, 1.07; p=0.77) and PFS3 (HR, 0.80; p=0.54).

 

“BEP** chemo also did not seem to improve efficacy compared with other chemo regimens in the first-line setting,” said Vanacker. However, at relapse, BEP seemed to have an advantage over other regimens, as reflected by the numerically improved PFS2 (HR, 0.57; multivariate analysis) and PFS3 (HR, 0.44; univariate analysis).

 

This retrospective descriptive analysis enrolled 469 women with malignant ovarian SCST (median age 49 years, 88 percent stage 1) from the parent SALOMÉ cohort who had initial surgery. The most common tumour subtypes were adult granulosa cell tumour (75 percent) and Sertoli Leydig cell tumour (13 percent). The rest had rarer subtypes***.

 

After a median follow-up of 6.4 years, a third of women developed first recurrence. Seventeen percent had a second relapse, while a tenth went on to have a third relapse.

 

Almost all surgeries were complete, with only about 2 percent receiving incomplete surgery. At the initial diagnosis, ~15 percent had adjuvant chemo, primarily with BEP (75 percent) followed by carboplatin/paclitaxel (16 percent).

 

In the relapse setting, 93, 72, and 60 percent of patients underwent surgery in the first, second, and third relapse, respectively.

 

Perioperative chemo was administered in ~60 percent of patients on first relapse. The rates dwindled at the second (28 percent) and third relapse (24 percent). Seven percent had chemo alone on first relapse, but this increased for the second and third relapse (17 percent and 31 percent, respectively).

 

At 5 years, PFS1 was 76 percent. PFS2 and PFS3 were 33 percent and 17 percent, respectively. Median follow-up for PFS2 was 40 months; for PFS3, it was 25 months. Overall survival was 97 percent.

 

“Ovarian SCST are very rare nonepithelial tumours representing 3–5 percent of ovarian neoplasms,” said Vanacker. Although surgery is the cornerstone of treatment for ovarian SCST, there is still a need to define which surgical modality^# would be the best standard of care for these patients.

 

The role of adjuvant therapies such as chemo or hormone therapy, and postop chemo for relapse, also needs to be addressed, Vanacker continued.

 

Another important challenge is the identification of these patients. “We need quality and accurate diagnosis in expert centres. We also need to better define their prognosis,” she added.

 

“Identifying prognostic factors and measuring the impact of adjuvant chemo in patients with SCST are challenging and must be addressed with large cohorts,” Vanacker continued. The current data support the need for randomized trials to ascertain the role of postop chemo in the advanced stages or during relapse.