Diagnostic impact of safety protocols for processing peritoneal washing specimens during the global pandemic of coronavirus disease 2019: A comparative study from 195 cytological samples

Abstract

Background Global pandemic of Coronavirus disease 2019 represented a major concern for the health services worldwide, also determining major changes in cytopathology practice. Aim We aimed to establish the diagnostic performance of cytologic evaluation with the new safety protocol to process cytological samples compared to the standard one. We also aimed to assess how cytological diagnoses and sampling were impacted during the pandemic period compared to the pandemic‐free period in 2019. Materials & Methods Peritoneal washings cytology samples received during COVID‐19 emergency in Italy (March 11, 2020 – January 11, 2021) were compared to the samples received during the same time frame in year 2019. Results 195 specimens were analyzed in the present study. We did not observe noticeable differences in cytological diagnoses during the pandemic period compared to the pre‐pandemic period in 2019. In fact, during pandemic and pre‐pandemic periods, we observed respectively 0 vs 0 non‐diagnostic (ND), 1 vs 7 atypia of uncertain significance (AUS), 3 vs 0 suspicious (SFM) diagnoses, 52 vs 86 negative for malignancy (NFM) and 4 vs 42 malignancies (MAL). Conclusion A consistent reduction in number of cytological samples has been observed during the COVID‐19 period. Finally, our institutional safety protocol for processing cytological samples did not affect the diagnostic reliability of peritoneal washing samples.

Review of the impact of the International System for Serous Fluid Cytopathology

“…The estimated ROM for each category was: ND, 0%-57.1%; NFM, Eleven studies provide data for peritoneal effusions, and ROM was assessed in seven of them (Table 3). 18,[20][21][22][24][25][26]29,31,35,36 The number of samples/patients ranged from 217 to 2257 in studies with reported ROM. The estimated ROM for each category was: ND, 0%-100%; NFM, 1.8%-27.5%; AUS, 22.2%-62.5%; SFM, 80%-100%; MAL, 100%.…”

“…In addition to the studies mentioned before, data regarding peritoneal washings cytology according to the TIS are presented by Santoro et al 35 without ROM evaluation, as this study mainly addressed the impact of Covid on the performance of a cytology lab. Peritoneal washings from patients with endometrial cancer without application of the TIS have also been discussed by Davis et al 40 The authors concluded that the cytology of peritoneal washings is a reliable diagnostic method with good performance and high reproducibility, even without application of the TIS criteria.…”