Impact of care by gynecologic oncologists on primary ovarian cancer survival: A population-based study

The role of surgeon specialty in management and survival of malignant ovarian germ cell tumors: A population-based study

OBJECTIVES

The aim of this study is to describe management and survival in adult patients with malignant ovarian germ cell tumors (MOGCT) undergoing surgery by general gynecologists (GG) versus gynecologic oncologists (GO).

METHODS

This is a population-based retrospective cohort study, including patients (age ≥ 18 years old) with MOGCT identified in the provincial cancer registry of Ontario, (1996-2020). Baseline characteristics, surgical and chemotherapy treatment were compared between those with surgery by GG or GO. Cox proportional hazards (CPH) model was used to determine if surgeon specialty was associated with overall survival (OS).

RESULTS

Overall, 363 patients were included. One-hundred and sixty (44%) underwent surgery by GO and 203 (56%) by GG. There were higher rates of stage II-IV in the GO group (27.5% vs 3.9%, p < 0.001, and higher proportion of chemotherapy (64.4% vs 37.4%, p < 0.0001). Five-year OS was 90% and 93% in the GO vs GG groups, respectively (p = 0.39). CPH model showed factors associated with increased risk of death were older age at diagnosis (HR 1.09, 95% CI 1.07-1.12) and chemotherapy (HR 3.12, 95% CI 1.44-6.75). Surgeon specialty was not independently associated with all-cause death (HR 1.04, 95% 0.51-2.15, p = 0.91).

CONCLUSIONS

In this group of MOGCT, 5-year OS was not significantly different between patients having surgery by GO compared to GG. Nevertheless, survival rates were lower than expected in the GG group despite their low-risk features. Further exploration is warranted regarding the reasons for this and whether patients with suspected MOGCT may benefit from early assessment by GO for optimal management.

Impact of obesity on chemotherapy dosing of carboplatin and survival of women with ovarian cancer

BACKGROUND

The study objective is to examine the impact of obesity on frontline carboplatin dosing in the neoadjuvant and adjuvant settings and to evaluate the association of dosing with survival among epithelial ovarian cancer (EOC) patients.

METHODS

We selected 1527 women diagnosed with EOC from January 1, 2011 to October 20, 2021 from a nationwide electronic health record-derived de-identified database. The dose reduction of frontline carboplatin was defined as a relative dose intensity (RDI) < 0.85. Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of RDI with survival overall and by histology.

RESULTS

Women with a BMI ≥ 30 kg/m2 versus <30 kg/m2 were more likely to be underdosed (RDI < 0.85) with frontline carboplatin. Underdosing of carboplatin in the neoadjuvant setting was associated with worse survival among women with serous tumours (HR = 1.98, 95% CI = 1.15, 3.42). Underdosing of carboplatin in the adjuvant setting was not associated with survival.

DISCUSSION

In the real-world setting, underdosing of carboplatin in the neoadjuvant setting was associated with inferior survival among women with serous tumours. With the increasing utilisation of neoadjuvant chemotherapy in EOC, actual weight-based dosing of carboplatin may be important to improve outcomes in this patient population.

Patterns of First-Line Systemic Therapy Delivery and Outcomes in Advanced Epithelial Ovarian Cancer in Ontario

Background: First-line treatment of epithelial ovarian cancer (EOC) consists of a combination of cytoreductive surgery and platinum-based chemotherapy. Recently, targeted therapies such as bevacizumab have been shown to improve oncologic outcomes in a subset of a high-risk population. The objective of this study is to evaluate the patterns of practice and outcomes of first-line systemic treatment of advanced EOC, focusing on the adoption of bevacizumab. Methods: A population cohort study was conducted using administrative data in Ontario, Canada. Patients diagnosed with advanced stage non-mucinous EOC between 2014 and 2018 were identified. Datasets were linked to obtaining information on first-line treatment including surgery, systemic therapy, providers of care, systemic therapy facilities, and acute care utilization (emergency department (ED) visits and hospitalizations) during systemic treatment. Multivariate logistic regression was used to determine factors associated with systemic therapy utilization. Results: Among 3726 patients with advanced EOC, 2838 (76%) received chemotherapy: 1316 (47%) received neoadjuvant chemotherapy, 1060 (37%) underwent primary cytoreductive surgery followed by chemotherapy, and 462 (16%) received chemotherapy only. The median age was 67 (range: 20–100). Most chemotherapies were prescribed by gynecologic oncologists (60%) and in level 1 academic cancer centres (58%). Only 54 patients (3.1%) received bevacizumab in the first-line setting after its approval in Ontario in 2016. Bevacizumab was more likely to be administered by medical oncologists compared to gynecologic oncologists (OR 3.95, 95% CI 2.11–7.14). In total, 1561 (55%) and 1594 (56%) patients had at least one ED visit and/or hospitalization during systemic treatment, respectively. The most common reasons for ED visits were fever and bowel obstruction. Conclusion: Patterns of care for EOC in Ontario differed between care providers. The uptake of bevacizumab for first-line treatment of EOC was low. Acute care utilization related to EOC was high.