Patient Characteristics at Baseline
The 166 hospitalized cancer COVID-19 patients had the median age of 65 years (59-70) and 49% (82/166) patients were male (Table 1). The patients consists of different primary tumor subtypes following WHO classification criteria (Table 2)[13]:most cases were of the digestive system (25%, 42/166), followed by the lung (15%, 25/166), and genitourinary (13%, 22/166); in terms of primary organ, lung cancer was the most frequently observed cancer type (15%, 25/166), followed by breast (11% ,19/166), and colon cancer (11% ,18/166).
At baseline, demographics characteristics of patients were well-balanced in all three cohorts (Table 1). Comorbidities among Cancer COVID-19 Cohort were generally similar with those among COVID-19 Cohort. But comparing to Cancer Cohort, Cancer COVID-19 Cohort were more likely to have diabetes (9% vs 15%, P=.07), hyperlipidemia (7% vs 20%, P<.001), hyperuricemia (3% vs 10%, P<.001), and COPD (1% vs 7%, P=.001), supporting the risks of these underlying conditions for COVID-19.
In terms of COVID-19 symptoms, Cancer COVID-19 Cohort were more likely to have expectoration (21% vs 36%, P<.001), dyspnea (16% vs 24%, P=.017), and consciousness disorder (4% vs 11%, P=.001) than COVID-19 Cohort, but less likely to have a sore throat (14% vs 7%, P=.02) or dry cough (53% vs 43%, P=.031) (Table 1). Cancer COVID-19 Cohort showed more severe complications such as Respiratory failure (16% vs 10%, P=.045), acute kidney injury (18% vs 8%, P=.001) and acute liver injury (32% vs 22%, P=.011) than COVID-19 Cohort (Table 1). Cancer COVID-19 Cohort presented with a higher level of C-reactive protein, white blood cell count, globulin protein, Aspartate transaminase, blood urea nitrogen, and blood glucose than COVID-19 Cohort (P<0.05), whereas red blood cell count, albumin protein, and high-density lipoprotein decreased (P<0.05) (Supplementary Table 3).
One-year All-Cause Mortality
Median follow-up time from the point of hospital admission was 12.2 (IQR 12.1-12.6) months (Table 3). In the Cox proportional hazards regression analysis, 30% (49/166) Cancer COVID-19 Cohort died within 12 months. It was 9% (44/498) in COVID-19 Cohort (relative risk=0.29; 95% CI 0.19 to 0.44, P<0.001), for an absolute risk difference of -19 percentage points (95% CI -13 to -29, P<0.001). The mortality was 16% (80/498) for Cancer Cohort (RR, 0.43; 95% CI 0.30 to 0.62, P<0.001), for an absolute risk difference of -13 percentage points (95% CI -9 to -19, P<0.001). Results were similar in the adjusted analysis. Figure 1A shows the main difference between Cancer COVID-19 Cohort and Cancer Cohort was in the first 2 months, 20% (34/166) and 4% (20/498). Between COVID-19 Cohort and Cancer Cohort, no statistical difference detected in the 3- to 4-month mortality (3.4 months being the time point where the two cohorts had same death rate), and 1-year mortality among COVID-19 Cohort was lower than that of Cancer Cohort (RR, 0.49; 95% CI 0.34 to 0.71, P<0001).
One-year Health Consequences
At the 1-year followed up, 56 cancer COVID-19 patients were excluded because 49 patients died and 7 patients couldn’t be reached; 70 COVID-19 patients were excluded because 44 patients died and 26 patients not reachable. As the result, 114 cancer COVID-19 patients and 432 COVID-19 participants were enrolled for questionnaire interview. In terms of having at least one symptom at the follow-up, the rate was 23% (26 /114) among Cancer COVID-19 Cohort, generally similar with the rate of 30% (130/432) in COVID-19 Cohort. Interesting, cancer COVID-19 Cohort were slightly little likely to have fatigue (4%, 12%, P=.016), chest congestion (3%, 9%, P=.027), and anxiety (0, 5%, P=.021) than COVID-19 Cohort (Table 3).
Hospital Mortality
Median length of hospital stay of 25 (IQR 15-33) days among Cancer COVID-19 Cohort was longer than the 21 (IQR 11-28) days for COVID-19 Cohort (Supplementary Table 4) (P=.005). Cancer COVID-19 Cohort were more severe COVID-19 (36% vs 20%, P<.001) than COVID-19 Cohort (Table 3). Cancer COVID-19 Cohort also required significantly more mechanical ventilation (14% vs 6%, P<0.001). Death in hospital occurred in 34/166 (20%) cancer COVID-19 patients; in 42/498 (8%) COVID-19 Cohort (relative risk, 0.36; 95% CI 0.22 to 0.59, P<0.001); and in 8/498 (2%) in Cancer Cohort (RR, 0.10; 95% CI 0.05 to 0.19, P<0.001).
Twelve-Month Post-Discharge Mortality
Median follow-up of cancer COVID-19 patients from the point of hospital discharged was11.2 (IQR10.8–11.6) months among who were discharged alive (Table 3 and Figure 1B). The 12-month all-cause post-discharge mortality rate was 11% (15/132) for Cancer COVID-19 Cohort, significantly higher than 0.4% (2/456, P<0.001) for COVID-19 Cohort, and showing no statistical difference from 15% (73/490, P=0.084) of Cancer Cohort.
Outcomes of Primary Tumor Subtype
For 1-year mortality, comparing to COVID-19 Cohort (9%, 44/498), COVID-19 patients with hematologic malignancies (65%, 11/17, P<0.001) had the highest rate, followed by a few solid such as brain/nasopharyngeal/bone and skin (45%, 5/11, P<0.001), digestive system tumors (43%, 18/42, P<0.001), and lung (32%, 8/25, P<0.001); COVID-19 patients with breast and endocrine tumors were associated with relatively low mortality (6%, 2/33, P=0.57), while patients with female genital tumors (13%, 2/16, P=0.43) and genitourinary (14%, 3/22, P=0.61) had moderate high mortality rate (Table 2 and Figure 2).Compared with the COVID-19 Cohort, patients with hematologic, brain, nasopharyngeal, digestive system and lung malignancies, combined as first group, showed a significantly higher risk of 1-year post admission mortality [5.7(3.8-8.8), P<0.001] and 12-month post discharge mortality [55.7(12.6-245.3), P<0.001]; patients with breast and endocrine, genitourinary and female genital tumors combined as second group, showed moderate risk of 1-year post admission mortality [1.1 (0.5-2.5), P=0.79] and 12-month post discharge mortality [3.6 (0.3-39.3), P=0.299] (Figure 2)。
Risk Factors for Outcomes of Cancer COVID-19 Cohort
In the multivariate cox regression model (Figure 3), we observed that male [HR 2.0, 95% CI 1.1-3.6], severe COVID-19 disease [non-severe; HR 7.5, 95%CI 3.9-14.6], hyperuricemia [HR 3.9, 95% CI 1.8-8.2], stroke [HR 3.7, 95% CI, 1.1-12.9], dyspnea [HR 3.1, 95% CI 1.6-5.8], consciousness disorder [HR 9.2, 95% CI, 4.5-18.2], respiratory failure[HR 11.4, 95% CI 5.3-24.6], acute kidney injury[HR 2.2, 95% CI 1.1-4.5] were significantly associated with increased mortality. Analysis characteristics of Cancer COVID-19 Cohort on 1-year all-cause mortality did not show any age bias.