PD-1 The impact of COVID-19 on diagnosis, stage and treatment of esophageal and gastric cancer

ABSTRACT

Background: During the COVID-19 pandemic, a profound decrease in the number of cancer diagnoses was observed. For patients with esophagogastric cancer, a diagnostic delay may have resulted in more advanced disease at the time of diagnosis. Also, downscaling of oncological care during COVID-19 may have resulted in postponed or different treatments. Therefore, we aimed to investigate the effects of the COVID-19 pandemic in 2020 on the stage at diagnosis and oncological care of esophagogastric cancer. Methods: Patients who were diagnosed in 2020 and included in the Netherlands Cancer Registry were allocated to 5 periods that correspond to the severity of the COVID-19 pandemic in the Netherlands. These were compared to patients diagnosed in the same period in the years 2017-2019. The number of diagnoses, tumor characteristics, type of treatment, time until the start of treatment and, in case of resection, the time between neoadjuvant therapy and resection were evaluated for esophageal cancer (EC) and gastric cancer (GC) separately. Results: The 2020 cohort in the Netherlands consisted of 2388 EC patients and 1429 GC patients. The absolute number of diagnoses decreased most prominently in the months March and April of 2020 for both EC and GC. The total number of EC diagnoses in 2020 decreased significantly compared to 2017-2019 (n=2522, p=0.027), whereas the total number of GC diagnoses did not decrease (n=1442, p=0.270). In the weeks after the first COVID-19 case in the Netherlands and before the COVID-19 lockdown, the percentage of incurable diagnoses increased from 52.5% to 67.7% for GC (p=0.011) and did not increase for EC (33.0% to 40.8%, p = 0.092). The percentage of patients with potentially curable EC receiving neoadjuvant chemoradiotherapy with resection decreased from 35.0% in 2017-2019 to 27.4% in 2020 (p < 0.001), whereas the percentage of patients receiving neoadjuvant chemoradiation without resection increased from 9.5% in 2017-2019 to 13.9% in 2020 (p < 0.001). The percentage of patients receiving definitive chemoradiation did not change significantly (p=0.119). For GC patients, no significant changes in type of treatment were found. The time between neoadjuvant chemotherapy and gastric resection decreased in 2020 with four days (p=0.006), while the time between neoadjuvant therapy and esophageal resection increased with 5 days (p=0.005). For both tumor types, the time between diagnosis and start of treatment was significantly shorter for patients diagnosed during and after the COVID-19 lockdown. Conclusions: We found a significant decrease in the number of EC diagnoses in 2020 and a shift in the type of treatment in potentially curable EC patients, with fewer resections being performed. Yet, it is unclear whether this is the result of the COVID-19 pandemic or due to an ongoing trial which implements watchful waiting after chemoradiotherapy. The oncological care for GC patients did not change during the COVID-19 pandemic. The shorter time between diagnosis and start of treatment may have been the result of a sense of urgency, since it was unknown in what way COVID-19 might affect the continuity of care in the upcoming future. Legal entity responsible for the study The authors. Funding: Has not received any funding. Disclosures All authors have declared no conflicts of interest.