ABSTRACT
Background: Vaccination is an essential strategy to prevent infection in the SARS-CoV-2 pandemic. However, there are concerns about vaccine efficacy and the impact of vaccination on cancer treatment. Additionally, the emergence of novel variants may affect vaccination efficacy. This multi-center, prospective, observational study investigated the efficacy and impact of vaccination against SARS-CoV-2 variants on treatment among breast cancer patients in Japan. Methods: Breast cancer patients scheduled to be vaccinated with the SARS-CoV-2 vaccine from May to November 2021 were included. They were stratified into five groups according to their cancer treatment: no treatment, endocrine therapy, CDK4/6 inhibitor, chemotherapy, anti-HER2 therapy. Serum samples were collected before the first vaccination and after the second vaccination. Immunoglobulin (Ig)G levels against the SARS-CoV-2 S protein and neutralizing antibody titers against wild-type (WT), alpha (α), delta (δ), kappa (κ), and omicron (o) variants were measured by ELISA assay. The effect of vaccination on cancer treatment was also investigated. Results: There were 85 eligible patients (no treatment, n = 5;endocrine therapy, n = 30;CDK4/6 inhibitor, n = 14;chemotherapy, n = 21;and anti-HER2 therapy, n = 15) with a median age of 65 years. The overall seroconversion rate of anti-SARS-CoV-2 IgG was 95.3%. The seroconversion rate of the chemotherapy group was 81.8%. The anti-SARS-CoV-2 IgG antibody concentration was positively correlated with the lymphocyte count before vaccination (r = 0.232, p = 0.039). Overall neutralizing antibody titers against each variant were significantly lower than for WT. Overall positive rates of neutralizing antibodies against WT, α, δ, γ, and o variants were 90.2%, 81.7%, 96.3%, 84.1%, and 8.5%, respectively. A downward trend of neutralizing antibody titers against each variant was seen in chemotherapy and CDK4/6 inhibitor groups compared with other groups. Significant decreases were detected in neutralizing antibody titers against WT, α, and κ variants in the chemotherapy group, and WT and α variants in the CDK4/6 inhibitor group compared with the no treatment group. Withdrawal or postponement of systemic therapy because of vaccination was only observed in one patient. Conclusions: Our data support SARS-CoV-2 vaccination for cancer patients being treated with systemic therapy. However, neutralizing antibody titers against the o variant were very low even after two vaccinations among patients with or without cancer treatment. Further, a decrease in neutralizing antibody titer was suggested during chemotherapy and CDK4/6 inhibitor, raising concerns about the impact on long-term infection prevention. For these patients, infection-preventive behaviors should be recommended even after vaccination. They will also be good candidates for booster vaccinations.
ABSTRACT
This case study describes a 45-year-old Caucasian male with a past medical history of obesity, hypertension, and non-insulin-dependent diabetes mellitus, who in the setting of coronavirus disease 2019 (COVID-19) pneumonia, developed portal vein thrombosis (PVT) presenting as an acute abdomen after hospital discharge from a cholecystitis episode. PVT is a very infrequent thromboembolic condition, classically occurring in patients with systemic conditions such as cirrhosis, malignancy, pancreatitis, diverticulitis, autoimmunity, and thrombophilia. PVT can cause serious complications, such as intestinal infarction, or even death, if not promptly treated. Due to the limited number of reports in the literature describing PVT in the COVID-19 setting, its prevalence, natural history, mechanism, and precise clinical features remain unknown. Therefore, clinical suspicion should be high for PVT, in any COVID-19 patient who presents with abdominal pain or associated signs and symptoms. To the best of our knowledge, this is the first report of COVID-19-associated PVT causing extensive thrombosis in the portal vein and its right branch, occurring in the setting of early-stage cirrhosis after a preceding episode of cholecystitis.