Exploring the prognostic impact of tumor sidedness in ovarian cancer: A population-based survival analysis of over 10,000 patients

Very recently, emerging evidence demonstrated that laterality might be an independent prognostic factor in patients with advanced ovarian cancer (OC). Based on preliminary provocative observations, our study aimed to investigate the prognostic impact of sidedness in a large cohort of women with OC. Survival was estimated based on Kaplan-Meier method and survival curves were compared using Log-rank test. Cox proportional-hazards model was used to study the association between survival and covariates. A total of 10,177 women with OC were included. Mean age at diagnosis was 59.58 years (±13.5); 36.7% OC right-sided, 36.9% were left- sided, and 26.4% had bilateral OC. The median overall survival (OS) for the entire population was 77 months, with the lowest median OS observed in bilateral OC (median OS: 34 months). The prognostic value of OC sidedness was not confirmed at the univariable analysis (HR = 0.958; 95% CI: 0.888-1.033, p = 0.268). However, women with bilateral OC has a 45% higher risk of death as compared with unilateral diagnosis (HR = 1.453; 95% CI: 1.410-1.497; p< 0.001). The independent prognostic value was further confirmed on multivarible analysis after adjusting for covariates including age, marital status, histological type, CA-125 at diagnosis, grade, stage, chemotherapy and surgery (HR = 1.087; 95% CI: 1.043-1.136, p = 0.02). However, the ultimate prognostic significance appeared less prominent, with bilateral OC conferring a relative increase of 8.7% of mortality. Our real-world study demonstrated that impact of tumor sidedness has no prognostic implication (right vs left OC) but bilateral OCs might be marginally more prognostically unfavorable. Prospective validation might be warranted, to confirm the prognostic significance of OC sidedness, including for the presence of key genetic alterations and lymph nodes asymmetry, to better stratify patients with OC and predict outcomes according to tumor sidedness at diagnosis.

The attributive value of comprehensive surgical staging in clinically early-stage epithelial ovarian carcinoma: A systematic review and meta-analysis

BACKGROUND

Tumor positivity and upstaging rates from various surgical staging steps performed in clinically early-stage epithelial ovarian carcinoma (EOC) vary widely in literature.

AIM

To quantify tumor positivity and upstaging rates for all staging surgery steps in EOC patients. Differences between subgroups based on their clinical and histological characteristics are explored.

METHODS

A systematic search using synonyms of 'ovarian cancer', 'neoplasm staging', and 'neoplasm metastasis' was conducted in PubMed, Embase, and the Cochrane Library. Meta-analysis was performed on 23 included studies, comprising 5194 clinical stage I or II EOC patients who underwent comprehensive surgical staging. Studies were assessed using the Newcastle-Ottawa Scale risk-of-bias tool. Pooled proportions and 95% confidence intervals were calculated using an inverse variance weighted random-effects model.

RESULTS

Overall upstaging rate of clinically early-stage EOC patients was 18.7% (95%CI: 14.1-23.4%). Serous histology or high grade EOC showed the highest upstaging rate at 35.3% (95%CI: 21.8-48.7%) and 40.9% (95%CI: 35.6-46.2%). Lymph node involvement resulted in an upstaging rate of 8.7% (95%CI: 6.2-11.3%). Tumor was identified in uterus, cytology, peritoneal biopsies, omentum and appendix in 6.2% (95%CI: 1.8-10.7%), 18.4% (95%CI: 13.8-22.9%), 9.7% (95%CI: 3.8-15.6%), 5.2% (95%CI: 1.7-8.8%) and 3.6% (95%CI: 0.0-7.5%) of EOC patients. The corresponding upstaging rates were 5.9% (95%CI: 1.4-10.4%), 8.5% (95%CI: 1.8-15.2%), 3.5% (95%CI: 1.0-6.0%), 3.9% (95%CI: 1.4-6.3%) and 1.6% (95%CI: 0.0-3.4%), respectively.

CONCLUSION

The attributive value of comprehensive surgical staging in clinically early-stage EOC patients remains substantial, particularly in serous and high grade tumors.