Difference in SARS-CoV-2 Antibody Status Between Patients With Cancer and Health Care Workers During the COVID-19 Pandemic in Japan.

IMPORTANCE

Patients with cancer and health care workers (HCWs) are at high risk of SARS-CoV-2 infection. Assessing the antibody status of patients with cancer and HCWs can help understand the spread of COVID-19 in cancer care.

OBJECTIVE

To evaluate serum SARS-CoV-2 antibody status in patients with cancer and HCWs during the COVID-19 pandemic in Japan.

DESIGN, SETTING, AND PARTICIPANTS: Participants were enrolled for this prospective cross-sectional study between August 3 and October 30, 2020, from 2 comprehensive cancer centers in the epidemic area around Tokyo, Japan. Patients with cancer aged 16 years or older and employees were enrolled. Participants with suspected COVID-19 infection at the time of enrollment were excluded.

EXPOSURES

Cancer of any type and cancer treatment, including chemotherapy, surgery, immune checkpoint inhibitors, radiotherapy, and targeted molecular therapy.

MAIN OUTCOMES AND MEASURES

Seroprevalence and antibody levels in patients with cancer and HCWs. Seropositivity was defined as positivity to nucleocapsid IgG (N-IgG) and/or spike IgG (S-IgG). Serum levels of SARS-CoV-2 IgM and IgG antibodies against the nucleocapsid and spike proteins were measured by chemiluminescent enzyme immunoassay.

RESULTS

A total of 500 patients with cancer (median age, 62.5 years [range, 21-88 years]; 265 men [55.4%]) and 1190 HCWs (median age, 40 years [range, 20-70 years]; 382 men [25.4%]) were enrolled. In patients with cancer, 489 (97.8%) had solid tumors, and 355 (71.0%) had received anticancer treatment within 1 month. Among HCWs, 385 (32.3%) were nurses or assistant nurses, 266 (22.4%) were administrative officers, 197 (16.6%) were researchers, 179 (15.0%) were physicians, 113 (9.5%) were technicians, and 50 (4.2%) were pharmacists. The seroprevalence was 1.0% (95% CI, 0.33%-2.32%) in patients and 0.67% (95% CI, 0.29%-1.32%) in HCWs (P = .48). However, the N-IgG and S-IgG antibody levels were significantly lower in patients than in HCWs (N-IgG: β, -0.38; 95% CI, -0.55 to -0.21; P < .001; and S-IgG: β, -0.39; 95% CI, -0.54 to -0.23; P < .001). Additionally, among patients, N-IgG levels were significantly lower in those who received chemotherapy than in those who did not (median N-IgG levels, 0.1 [interquartile range (IQR), 0-0.3] vs 0.1 [IQR, 0-0.4], P = .04). In contrast, N-IgG and S-IgG levels were significantly higher in patients who received immune checkpoint inhibitors than in those who did not (median N-IgG levels: 0.2 [IQR, 0.1-0.5] vs 0.1 [IQR, 0-0.3], P = .02; S-IgG levels: 0.15 [IQR, 0-0.3] vs 0.1[IQR, 0-0.2], P = .02).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study of Japanese patients with cancer and HCWs, the seroprevalence of SARS-CoV-2 antibodies did not differ between the 2 groups; however, findings suggest that comorbid cancer and treatment with systemic therapy, including chemotherapy and immune checkpoint inhibitors, may influence the immune response to SARS-CoV-2.