Correlation between progression-free survival and overall survival in patients with ovarian cancer after cytoreductive surgery: a systematic literature review

The value of PFS36 as a primary endpoint for radiotherapy trials in patients with LACC: individual patient data from the Chinese NCC and validation from 26 RCTs

Objective

A conventional endpoint for locally advanced cervical cancer (LACC) clinical trials is overall survival (OS) with five years of follow-up. The primary hypothesis was that progression-free survival (PFS) with three years of follow-up (PFS36) would be an appropriate primary surrogate endpoint.

Materials and methods

The primary hypothesis, which was developed from our data, was further investigated using phase III randomized controlled trials and then externally validated using retrospective studies up to 2023. Correlation analysis at the treatment-arm level was performed between 2-, 3-, 4-, and 5-year PFS rates and 5-year OS.

Results

A total of 613 patients with histologically confirmed cervical cancer who underwent radiotherapy or chemoradiation at our institute between January 2010 and December 2013 were eligible. The recurrence rates for years 1 through 5 were 12.9%, 7.3%, 3%, 2.3%, and 1.8%, respectively. Patients who did not achieve PFS36 had a 5-year OS rate of 30.3%. However, patients who achieved PFS36 had a 5-year OS rate of 98.2%. Further data were extracted from 26 randomized phase III trials on LACC. The trials included 55 arms, with a pooled sample size of 7,281 patients. Trial-level surrogacy results revealed that PFS36 (r2, 0.732) was associated with 5-year OS. The correlation between PFS36 and OS was externally validated using independent retrospective data.

Conclusion

A significant positive correlation was found between PFS36 and OS at 5 years of follow-up both within patients and across trials. These results suggest that PFS36 is an appropriate endpoint for LACC clinical trials of radiotherapy-based regimens.

Real-life treatment patterns and time to next treatment among patients with ovarian cancer in the pre-PARP inhibitor era: the OCRWE-Finland Study

BACKGROUND

As the treatment landscape for advanced ovarian cancer (OC) evolves, it is important to understand patient outcomes in real-world clinical practice. OCRWE-Finland was an observational cohort study investigating OC outcomes, including treatment patterns, time to next treatment 1 (TTNT1), overall survival and healthcare resource utilisation, in Finland during the pre-PARPi era.

MATERIALS AND METHODS

Patients included in OCRWE-Finland were diagnosed with OC between 2014 and 2019. Here, we report treatment patterns and TTNT1 outcomes (as a surrogate for progression-free survival) for patients in the high-grade serous ovarian carcinoma (HGSOC) cohort.

RESULTS

In OCRWE-Finland, there were 867 patients with HGSOC. Of the 811 patients who received first-line treatment, the most common regimen was surgery and adjuvant chemotherapy (53%), and 227 patients also received first-line bevacizumab. Median TTNT1 among 623 patients with stage III/IV disease was 19 months (95% confidence interval, 18-21 months), with no difference between patients with stage III or IV disease (p = 0.24). The presence versus absence of visible residual disease post-debulking surgery was associated with shorter TTNT1 among patients with stage III tumours (p = 0.031) but showed no impact for stage IV tumours (p = 0.55). First-line versus no first-line bevacizumab was associated with shorter TTNT1 among stages I-IV (p < 0.0001) but did not affect patients with stage III/IV tumours (p = 0.45).

INTERPRETATION

In the pre-PARPi era, prognosis for advanced OC was poor, particularly for patients with stage III tumours and visible residual disease or stage IV tumours regardless of the presence of residual disease. The increasing use of PARPis will hopefully help address the need for effective treatments in advanced OC.

The impact of varying levels of residual disease following cytoreductive surgery on survival outcomes in patients with ovarian cancer: a meta-analysis

BACKGROUND

Residual disease following cytoreductive surgery in patients with ovarian cancer has been associated with poorer survival outcomes compared with no residual disease. We performed a meta-analysis to assess the impact of varying levels of residual disease status on survival outcomes in patients with ovarian cancer who have undergone primary cytoreductive surgery or interval cytoreductive surgery in the setting of new therapies for this disease.

METHODS

Medline, Embase, and Cochrane databases (January 2011 - July 2020) and grey literature, bibliographic and key conference proceedings, were searched for eligible studies. Fixed and random-effects meta-analyses compared progression and survival by residual disease level across studies. Heterogeneity between comparisons was explored via type of surgery, disease stage, and type of adjuvant chemotherapy.

RESULTS

Of 2832 database and 16 supplementary search articles screened, 50 studies were selected; most were observational studies. The meta-analysis showed that median progression-free survival and overall survival decreased progressively with increasing residual disease (residual disease categories of 0 cm, > 0-1 cm and > 1 cm). Compared with no residual disease, hazard ratios (HR) for disease progression increased with increasing residual disease category (1.75 [95% confidence interval: 1.42, 2.16] for residual disease > 0-1 cm and 2.14 [1.34, 3.39] for residual disease > 1 cm), and also for reduced survival (HR versus no residual disease, 1.75 [ 1.62, 1.90] for residual disease > 0-1 cm and 2.32 [1.97, 2.72] for residual disease > 1 cm). All comparisons were significant (p < 0.05). Subgroup analyses showed an association between residual disease and disease progression/reduced survival irrespective of type of surgery, disease stage, or type of adjuvant chemotherapy.

CONCLUSIONS

This meta-analysis provided an update on the impact of residual disease following primary or interval cytoreductive surgery, and demonstrated that residual disease was still highly predictive of progression-free survival and overall survival in adults with ovarian cancer despite changes in ovarian cancer therapy over the last decade. Higher numerical categories of residual disease were associated with reduced survival than lower categories.

Impact of Pre-Diagnostic Risk Factors on Short- and Long-Term Ovarian Cancer Survival Trajectories: A Longitudinal Observational Study

Tumor- and treatment-related factors are established predictors of ovarian cancer survival. New studies suggest a differential impact of exposures on ovarian cancer survival trajectories (i.e., rapidly fatal to long-term disease). This study examined the impact of pre-diagnostic risk factors on short- and long-term ovarian cancer survival trajectories in the Canadian context. This population-based longitudinal observational study included women diagnosed with invasive epithelial ovarian cancer from 1995 to 2004 in Ontario. Data were obtained from medical records, interviews, and the provincial cancer registry. Extended Cox proportional hazard models estimated the association between risk factors and all-cause and ovarian cancer-specific mortality by survival time intervals (<3 years (i.e., short-term survival), 3 to <6 years, 6 to <10 years, and ≥10 years (i.e., long-term survival)). Among 1421 women, histology, stage, and residual disease were the most important predictors of all-cause mortality in all survival trajectories, particularly for short-term survival. Reproductive and lifestyle factors did not strongly impact short-term overall survival but were associated with long-term overall survival. As such, among long-term survivors, history of breastfeeding significantly decreased the risk of all-cause mortality (HR 0.65; 95% CI 0.46, 0.93; p < 0.05), whereas smoking history (HR 1.75; 95% CI 1.27, 2.40; p < 0.05) and obesity (HR 1.81; 95% CI 1.24, 2.65; p < 0.05) significantly increased the risk of all-cause mortality. The findings were consistent with ovarian cancer-specific mortality. These findings suggest that pre-diagnostic exposures differentially influence survival time following a diagnosis of ovarian cancer.

Front-line chemo-immunotherapy for treating epithelial ovarian cancer: Part I CA125 and anti-CA125

The current standard therapy of epithelial ovarian cancer (EOC) is the combination of surgery (primary cytoreductive surgery or interval cytoreductive surgery) and platinum-based chemotherapy (mainly using paclitaxel and carboplatin either by neoadjuvant chemotherapy and/or by postoperative adjuvant chemotherapy) with/without adding targeted therapy (mainly using anti-angiogenesis agent- bevacizumab). After front-line chemotherapy, the advanced-stage EOC can be successfully controlled and three-quarters of patients can achieve a complete clinical remission. Unfortunately, nearly all patients will recur and progression-free survival (PFS) of these patients is seldom more than 3 years with a dismal median PFS of 12-18 months. With each recurrence, patients finally develop resistance to standard chemotherapy regimen, contributing to fewer than half of women who survive for more than 5 years after diagnosis with a median overall survival (OS) of 40.7 months. Due to the lower PFS and OS, particularly for those advanced-stage patients, novel therapeutic options during the front-line therapy are desperately needed to decrease the occurrence of recurrence, and the majority of them are still under investigation. It is well-known that overexpression of CA125 has been associated with attenuated cellular apoptosis, platinum chemotherapy resistance, tumor proliferation and disease progression, suggesting that anti-CA125 may play a role in the management of patients with EOC. The current review is a Part I which will focus on development of anti-CA125 monoclonal antibody, hoping that alternation of the front-line therapy by chemo-immunotherapy will be beneficial for prolonged survival of patients with EOC.