The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

Isolation and molecular genetic characterization of a yeast strain able to degrade petroleum polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) belong to a class of toxic environmental pollutants and PAH exposure causes public health risks and raises environmental concerns. Identification of the keymicroorganisms that play a role in pollutant degradation processes is relevant to the development of optimal in situ bioremediation strategies. In the current study, three yeast strains were isolated from oilcontaminated soil by enrichment technique in mineral basal salts (MBS) medium supplemented with phenanthrene as a sole carbon source. Out of these, strain AH70 was selected for PAHs degradation,because of its fast growth on agar plate coated by PAHs as sole source of carbon and energy. The yeast was identified by molecular genetics technique based on sequence analysis of the variable D1/D2domain of the large subunit (26S) ribosomal DNA. Subsequent 26S rRNA gene sequencing showed 100% base sequence homology and it was identified as Candida viswanathii. The degradation of PAHsby this yeast was confirmed by GC-MS analyses. The yeast was capable of degrading a mixture of low and high molecular weight PAHs and degradation efficiency was found as 89.76% for naphthalene,77.21% for phenanthrene, 60.77% for pyrene and 55.53% for benzo(a)pyrene at the end of 10 days