A novel classification of residual disease after interval debulking surgery for advanced-stage ovarian cancer to better distinguish oncologic outcome

BACKGROUND

Complete surgical resection affords the best prognosis at the time of interval debulking surgery. When complete surgical resection is unachievable, optimal residual disease is considered the next best alternative. Despite contradicting evidence on the survival benefit of interval debulking surgery if macroscopic residual disease remains, the current definition of "optimal" in patients undergoing interval debulking surgery is defined as largest diameter of disease measuring ≤1.0 cm, independent of the total volume of disease.

OBJECTIVE

To examine the relationship between volume and anatomic distribution of residual disease and oncologic outcomes among patients with advanced-stage epithelial ovarian/fallopian tube/primary peritoneal carcinoma undergoing neoadjuvant chemotherapy then interval debulking surgery. For patients who did not undergo a complete surgical resection, a surrogate for volume of residual disease was used to assess oncologic outcomes.

STUDY DESIGN

Patient demographics, operative characteristics, anatomic site of residual disease, and outcome data were collected from medical records of patients with International Federation of Gynecology and Obstetrics stage IIIC and IV epithelial ovarian cancer undergoing interval debulking surgery from January 2010 to July 2015. Among patients who did not undergo complete surgical resection but had ≤1 cm of residual disease, the number of anatomic sites (single location vs multiple locations) with residual disease was used as a surrogate for volume of residual disease. The effect of residual disease volume on progression-free survival and overall survival was evaluated.

RESULTS

Of 270 patients undergoing interval debulking surgery, 173 (64.1%) had complete surgical resection, 34 (12.6%) had ≤1 cm of residual disease in a single anatomic location, 47 (17.4%) had ≤1 cm of residual disease in multiple anatomic locations, and 16 (5.9%) were suboptimally debulked. Median progression-free survival for each group was 14, 12, 10, and 6 months, respectively (P<.001). Median overall survival for each group was: 58, 37, 26, and 33 months, respectively (P<.001).

CONCLUSION

Following interval debulking surgery, patients with complete surgical resection have the best prognosis, followed by patients with ≤1 cm single-anatomic location disease. In contrast, despite being considered "optimally debulked," patients with ≤1 cm multiple-anatomic location disease have a survival similar to suboptimally debulked patients.

Outcome of Epithelial Ovarian Cancer: Time for Strategy Trials to Resolve the Problem of Optimal Timing of Surgery

INTRODUCTION

The standard treatment of ovarian cancer is the combination of debulking surgery and chemotherapy. There is an ongoing discussion on which treatment is best: primary debulking surgery (PDS) or neoadjuvant chemotherapy with interval debulking (NACT-IDS). Even a large randomized trial has not settled this issue. We examined whether comparing a specified treatment protocol would not be a more logical approach to answer this type of discussions.

METHODS

A retrospective study of 142 consecutively treated patients according to a fixed protocol between 2000 and 2012 was conducted. Disease-free survival and overall survival were calculated by univariate and multivariate analyses for the whole group and for advanced stages separately. Specific differences between PDS and NACT-IDS were studied. Comparison of results from large databases was made.

RESULTS

Disease-free survival and overall 5-year survival for the whole group were 35% and 50%. For the advanced stages, disease-free survival and overall 5-year survival were 14% and 36%, with a median disease-free and overall survival of 16 and 44 months. Of the 98 women with advanced ovarian carcinoma, 54% of operable patients underwent PDS and 44% underwent NACT-IDS. More patients in the PDS group were optimally (<1 cm) debulked: 80% vs 71%. There was no significant difference in survival between PDS or NACT-IDS. Optimally debulked patients had a significant better overall survival in multivariate analysis with a hazard ratio of 2.1.

DISCUSSION

Outcome of treatment according to a fixed protocol with a mixture of PDS and NACT-IDS was similar to results from large databases. We hypothesize that comparison of a specific strategy may yield more useful results than awaiting the perfect randomized trial.

Interval debulking surgery for advanced epithelial ovarian cancer

BACKGROUND

Interval debulking surgery (IDS), following induction or neoadjuvant chemotherapy, may have a role in treating advanced epithelial ovarian cancer (stage III to IV) where primary debulking surgery is not an option.

OBJECTIVES

To assess the effectiveness and complications of IDS for women with advanced stage epithelial ovarian cancer.

SEARCH METHODS

We searched the Cochrane Gynaecological Cancer Group's Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) 2012, Issue 6, MEDLINE and EMBASE for the original review in to June 2012. We updated the searches in June 2009, 2012 and 2015 for the review updates.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing survival of women with advanced epithelial ovarian cancer, who had IDS performed between cycles of chemotherapy after primary surgery with survival of women who had conventional treatment (primary debulking surgery and adjuvant chemotherapy).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Searches for additional information from study authors were attempted. We performed meta-analysis of overall and progression-free survival (PFS), using random-effects models.

MAIN RESULTS

Three RCTs randomising 853 women, of whom 781 were evaluated, met the inclusion criteria. Meta-analysis of three trials for overall survival (OS) found no statistically significant difference between IDS and chemotherapy alone (hazard ratio (HR) = 0.80, 95% confidence interval (CI) 0.61 to 1.06, I² = 58%). Subgroup analysis for OS in two trials, where the primary surgery was not performed by gynaecologic oncologists or was less extensive, showed a benefit of IDS (HR = 0.68, 95% CI 0.53 to 0.87, I² = 0%). Meta-analysis of two trials for PFS found no statistically significant difference between IDS and chemotherapy alone (HR = 0.88, 95% CI 0.57 to 1.33, I² = 83%). Rates of toxic reactions to chemotherapy were similar in both arms (risk ratio = 1.19, 95% CI 0.53 to 2.66, I² = 0%), but little information was available for other adverse events or quality or life (QoL).

AUTHORS' CONCLUSIONS

We found no conclusive evidence to determine whether IDS between cycles of chemotherapy would improve or decrease the survival rates of women with advanced ovarian cancer, compared with conventional treatment of primary surgery followed by adjuvant chemotherapy. IDS appeared to yield benefit only in women whose primary surgery was not performed by gynaecologic oncologists or was less extensive. Data on QoL and adverse events were inconclusive.

Neoadjuvant chemotherapy in gynaecological cancers - Implications for staging

The management of advanced gynaecological cancers remains a therapeutic challenge. Neoadjuvant chemotherapy has been used to reduce tumour size, thus facilitating subsequent local treatment in the form of surgery or radiation. For advanced epithelial ovarian cancer, data from several non-randomized and one randomized studies indicate that neoadjuvant chemotherapy followed by interval debulking surgery is a reasonable approach in patients deemed inoperable. Such an approach results in optimum debulking (no visible tumour) in approximately 40% of the patients with reduced operative morbidity. Overall and progression free-survival is comparable to the group treated with primary debulking surgery followed by chemotherapy. Neoadjuvant chemotherapy followed by surgery is associated with improved survival for women with stage IB2-IIA cervix cancer. There is a resurgence of interest for using short-course neoadjuvant chemotherapy prior to concurrent chemo-radiation. Currently, this is being tested in randomized trials.