Study Links COVID-19 Pandemic to Rise in Neoadjuvant Chemotherapy for Ovarian Cancer in US

The COVID-19 pandemic was associated with an increased use of neoadjuvant chemotherapy in US patients with advanced ovarian cancer (OC), according to a study published in Frontiers in Oncology.

The researchers explained that the COVID-19 pandemic caused delays in cancer diagnosis and treatment initiation. In terms of gynecologic cancers, there were cervical cancer screening service discontinuations, treatment initiation delays, and surgical procedure postponements; the pandemic also caused reductions in emergency visits and urgent referrals among patients with suspected cancer.

Because of pandemic-related shortages, the researchers explained that the American College of Surgeons categorized gynecological cancer cases as semi-urgent. Simultaneously, to reduce harm and accommodate delays in ovarian cancer surgery, the Society of Gynecologic Oncology recommended using neoadjuvant chemotherapy during the pandemic.

The researchers explained that although primary cytoreductive surgery is the first-line treatment choice for patients with ovarian cancer, another treatment option is neoadjuvant chemotherapy followed by interval cytoreductive surgery. However, evidence on the impact of neoadjuvant chemotherapy use among US patients with OC during the pandemic has not yet been reported. Consequently, the researchers aimed to assess the association of the COVID-19 pandemic with neoadjuvant chemotherapy use in patients with diagnosed OC.

To reduce harm and accommodate for delays in ovarian cancer surgery, the Society of Gynecologic Oncology recommended using neoadjuvant chemotherapy during the COVID-19 pandemic | Image Credit: catinsyrup - stock.adobe.com

To do so, the researchers analyzed patients who received a diagnosis of incident epithelial OC between January 1, 2017, and June 30, 2021, at Kaiser Permanente Southern California (KPSC), an integrated health care delivery system; they included patients aged 18 to 89 years whose cancer was diagnosed at stage II through stage IV and who were active members of the KPSC health plan at the time of diagnosis.

The researchers identified patients with epithelial type OC between 2017 and 2020 through KPSC’s Surveillance, Endpoints, & End Results–affiliated cancer registry. Conversely, they identified patients who received their diagnosis in 2021 from KPSC’s electronic medical records using International Classification of Diseases, Tenth Revision diagnosis codes and later confirmed by chart review.

Overall, their outcome of interest was neoadjuvant chemotherapy use, while the COVID-19 pandemic period was the exposure of interest; March 4, 2020, was the cut-off to define prepandemic and pandemic periods based on the date of implementation of California’s stay-at-home order. Also, the researchers' covariates of interest included age at cancer diagnosis, cancer stage, KPSC membership years before OC diagnosis, and race and ethnicity.

Of 566 patients identified with stage II through stage IV OC, 406 (71.7%) received their diagnosis during the prepandemic period and 160 (28.3%) during the pandemic period; most patients' (85.5%) cancer was diagnosed at either stage III or stage IV OC. The researchers noted that patients who received their diagnosis during the pandemic era were slightly younger than those who received their diagnosis during the prepandemic period (mean age, 62.7 vs 64.9 years; P = .07).

They found that 50.5% of the overall study population received neoadjuvant chemotherapy, which included 58.7% and 47.3% who received their diagnosis during the pandemic and prepandemic periods, respectively (P = .01). The mean (SD) time from diagnosis to neoadjuvant treatment initiation among the population was 22.3 (24.5) days, with no differences observed by pandemic periods (P = .17).

In the unadjusted model, the researchers found that patients who received their diagnosis in the pandemic period were 24% more likely to receive neoadjuvant chemotherapy (risk ratio [RR], 1.24; 95% CI, 1.04-1.47), as were those with stage III (RR, 5.42; 95% CI, 2.64-11.12) and stage IV (RR, 9.07; 95% CI, 4.44-18.50) OC compared with stage II OC.

However, after adjusting for age, cancer stage, comorbidity index, and race and ethnicity, the researchers reported that patients with a diagnosis in the pandemic period were 29% more likely to receive neoadjuvant chemotherapy (RR, 1.29; 95% CI, 1.12-1.49). Also, in terms of race, Hispanic (RR, 1.46; 95% CI, 1.13-1.88) and non-Hispanic White (RR, 1.27; 95% CI, 1.04-1.54) patients were 46% and 27%, respectively, more likely to receive neoadjuvant chemotherapy during the pandemic period.

The researchers acknowledged their study’s limitations, one being that they did not have information on neoadjuvant therapy dose, meaning they were unable to assess if the COVID-19 pandemic affected the recommended neoadjuvant chemotherapy dose in patients with OC. Also, their study population consisted of insured patients within KPSC, so the findings may not be generalizable to other cohorts. Despite these limitations, the researchers suggested areas for future research based on their findings.

“Future studies are needed to assess the impact of the pandemic on treatment patterns and cancer outcomes, including response to cancer treatments and survival in patients with ovarian cancers,” the authors concluded.

Reference

Mukherjee A, Shammas N, Xu L, et al. Impact of the coronavirus disease 2019 pandemic on neoadjuvant chemotherapy use in patients diagnosed with epithelial type ovarian cancer. Front Oncol. 2024;14:1290719. doi:10.3389/fonc.2024.1290719