In this study, we showed that although the age and gender distribution of gastric cancer have not changed during COVID-19 pandemic but there is a shift toward more locally advanced tumors; as N stage is getting higher and more cases are presented with disseminated peritoneal cancer at the time of SL.
This finding may be due to the interruption in national cancer screening programs, the use of diagnostic modalities, closure of medical facilities related to oncological evaluation because of resource modification, delay in multidisciplinary sessions for treatment planning of the cancer patients, patients’ fear to come to hospitals and overcrowded hospitals with COVID-19 patients[17–19].
New York Society for Gastrointestinal Endoscopy [20, 21] and the European Society of Gastrointestinal Endoscopy (ESGE) emphasized to minimize endoscopy utilization during the pandemic because its aerosol-generating potential may cause COVID-19 infection. Zhu et al., adopted these guidelines and demonstrated that there was an expeditious decrease in elective endoscopic procedures compared to pre-COVID-19 time (911 vs 5746). Their study was suggestive of an increase in the detection rate of upper gastrointestinal malignancies during the pandemic (7.2% Vs 2.2%) but, we assume this finding is because of reduction in total number of endoscopic procedures performed. In our study, we did not found a significant increase in total number of gastric cancer diagnosed.
COVID-19 pandemic subtracted resources away from all other disease; thus even in developed countries and properly funded facilities there are short comes in the budget [24, 25]. This may be a reason to cancel elective surgeries including gastrectomy. Torzilli et al., reported a vast reduction in surgical beds dedicated to cancer patients, a decrease in number of oncologic surgeries performed per week and increased interval time between multidisciplinary team decisions for surgery and performing it in Italy after the pandemic. In our center, we experienced the same situation as described above besides a tragedy happened in our operation room. Before the beginning of the first wave of national lockdown during June 21th and June 28th nearly all the staff of the operation room became infected with the COVID-19. As a result, the operation room was shut down for one week. This disaster ringed a bell to reconsider all the protocols of patient admission, personal protective equipment quality and availability and daily number of staff attending to work.
The Society of Surgical Oncology (SSO) and the European Society for Diseases of the Esophagus (ESDE) proposed guidelines for the surgical management of esophageal or gastric cancer cases during the pandemic which are quite the same in principle rules and adoption of more conservative approaches toward early stages of cancer and leaving the surgery for hemorrhage or gastric outlet obstruction which are refractory to endoscopic/interventional radiological management. The other group of gastric patients who needed to be operated are those who had already completed their neoadjuvant chemotherapy and had undergone a post-chemotherapy assessment of resectability/treatment response. A quite remarkable study was done by Fligor et al., in form of a systematic review aiming at investigating the impact of time to surgery on oncologic outcomes of gastric cancer. Although the studies investigated in this systematic review had heterogeneous populations in terms of gastric cancer stage, neoadjuvant chemotherapy, number of participants and time interval to surgery but finally the authors concluded that the interval to surgery did not impact overall survival or disease-free survival, but the time to surgery over 6 weeks improved pathologic complete response. This statement is in contrast with what was found in Sud et al., study. They designed a per-day hazard ratios of cancer progression from observational studies and applied these to age-specific, stage-specific cancer survival for England 2013–2017. As a result, it revealed that the greatest rates of deaths arised following even modest delays to surgery in aggressive cancers, with > 30% reduction in survival at 6 months and > 17% reduction in survival at 3 months for patients with stage 2 or 3 cancers of the bladder, lung, esophagus, ovary, liver, pancreas and stomach. This finding is shocking that each day delay may have devastating results. Turaga et al., used the National Cancer Database and developed models to examine the effect of each one week delay in definitive surgery from diagnosis. The earliest interval when the effect estimate was worse than the previous interval, and statistically different from the baseline was defined as the inflection point. Time to inflection point beyond median current wait time was considered the safe postponement period. For patients with gastric cancer whom underwent surgery prior to chemotherapy; 6, 12, 12 and 12 weeks can be safely deferred from the time of diagnosis without significant impact on 1-year, 3-year, 5-year mortality rates and possibility of complete tumor resection, respectively. Also, for those patients underwent neoadjuvant chemotherapy 12, 12, 9 and 12 weeks are safe intervals without jeopardizing survival benefits after 1-year, 3-year, 5-year and feasibility to completely resect the tumor, respectively. Based on the current guidelines for management of gastric cancer like NCCN 2020 and UpToDate®, SL is needed to accurately investigate the stage of local invasion of the tumor. Nevertheless, the performance of this modality can be challenging as the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) and the European Association for Endoscopic Surgeons (EAES) advised to defer elective laparoscopic surgeries. As we showed, this delay might result in an increase in N stage of the tumor and change treatment plan. Besides in patients who received neoadjuvant chemotherapy, presumptive peritoneal seeding might be cleared with treatment but as the time interval between chemotherapy cession and surgery gets longer, the possibility to reach R0 resection gets lower.
The current study suffers from few limitations should be kept in mind while interpreting the results. We used retrospective design with limited numbers of patients in each group. Also, the diagnostic evaluations were not completely unified as some patients had their CT scan or ultrasound upper endoscopy in facilities other than our center which might have impact on the reported T and N.