COVID-19 Recovery and Abdominal Cancer Surgical Outcomes: An NCDB Analysis
Peter L. Zhan*1, Maureen E. Canavan2, Sora Ely1, Brooks Udelsman1, Winston Trope1, Daniel J. Boffa1, Ira L. Leeds1
1Department of Surgery, Yale University School of Medicine, New Haven, CT; 2Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, CT
Objective. Guidelines in 2020 suggested delaying surgery at least 6 weeks after COVID-19 infection. We strove to identify whether oncologic surgery prior to 6 weeks after COVID-19 infection was associated with worse surgical outcomes.
Design. Retrospective cohort study.
Setting. National Cancer Database Participant User File.
Patients.
In total, 101,402 adult patients diagnosed with stage I-IV abdominal cancer (stomach, colorectal, liver, pancreas, kidney, bladder, prostate, cervix, uterine, ovarian) in 2020 who underwent definitive oncologic surgery and were tested for COVID-19 were included: 99,216 patients (98%) tested negative for COVID-19 [COVID(-)], 908 patients (1%) received definitive surgery <6 weeks after COVID-19 infection (Surgery <6w post-COVID), and 1,278 (1%) received surgery "‰¥6 weeks after COVID-19 infection (Surgery "‰¥6w post-COVID). The median age was 64 (IQR: 57-71), and 47,699 (47%) were female.
Interventions. N/A.
Main Outcome Measure(s). Postoperative length of stay (LOS), 30-day postoperative readmission, and rates of adjuvant therapy (systemic or radiation) administration in indicated patients, according to National Comprehensive Cancer Network (NCCN) guidelines.
Results.
Among cohorts propensity matched for cancer type, comorbidities, neoadjuvant treatment, and sociodemographic, socioeconomic, and facility characteristics, no differences in LOS between the three groups were identified using t-tests (p = 0.53 for Surgery <6w post-COVID vs. Surgery "‰¥6w post-COVID; p = 0.07 for COVID(-) vs. Surgery <6w post-COVID; p = 0.69 for COVID(-) vs. Surgery "‰¥6w post-COVID) (Figure 1).
No differences in rates of 30-day readmission were found among the three groups in both unadjusted (X2) (Table 1) and adjusted (multivariable logistic regression model) analysis. The readmission rates were 3.7% for COVID(-) patients (reference), 3.5% for Surgery <6w post-COVID patients (OR, 0.88; 95% CI, 0.62-1.26; p = 0.48), and 3.8% for Surgery "‰¥6w post-COVID patients (OR, 0.91; 95% CI, 0.68-1.21; p = 0.51).
No differences in rates of adjuvant therapy were found among the three groups in both unadjusted (X2) (Table 2) and adjusted (multivariable logistic regression model) analysis. Overall, of the 14,566 in whom adjuvant therapy was recommended by NCCN guidelines, 7,928 (54%) started adjuvant therapy within 8 weeks postoperatively. This was 54% for COVID(-) patients (reference), 55% for Surgery <6w post-COVID patients (OR, 1.09; 95% CI, 0.78-1.53; p = 0.61), and 52% for Surgery "‰¥6w post-COVID patients (OR, 0.88; 95% CI, 0.61-1.28; p = 0.51).
Conclusions.
In this National Cancer Database study, definitive oncologic surgery performed before 6 weeks post-COVID-19 infection was not a marker of worse surgical outcomes with respect to length of stay, readmission rates, or guideline compliance with adjuvant therapy. These findings challenge whether current recommended delays after COVID-19 infection are warranted for abdominal surgery.
30-Day Postoperative Readmission Rates by COVID-19 Status
| Unplanned Readmission | COVID(-), n (col%) | Surgery <6w Post-COVID | Surgery "‰¥6w Post-COVID | Chi-sq p-value |
| Yes | 3692 (3.7%) | 32 (3.5%) | 48 (3.8%) | 0.54 |
| No | 94856 (95.6%) | 874 (96.3%) | 1220 (95.5%) |
Rates of NCCN Guideline-Adherent Adjuvant Therapy by COVID-19 Status*
| Adjuvant Therapy Initiated "‰¤8w** Postoperatively | COVID(-), n (col %) | Surgery <6w Post-COVID | Surgery "‰¥6w Post-COVID | Chi-sq p-value |
| No | 6513 (45.6%) | 68 (45.0%) | 57 (48.3%) | 0.83 |
| Yes | 7784 (54.4%) | 83 (55.0%) | 61 (51.7%) |
*Analysis was restricted to patients in whom adjuvant therapy was indicated.
**8w: 8 weeks
Figure 1. Length of Stay Among Propensity Matched Cohorts.
*Surgery <6 weeks after COVID-19 infection.
**Surgery "‰¥6 weeks after COVID-19 infection. Comparisons were performed using Student's t-tests after propensity matching.
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