Serological response to COVID-19 vaccine and its predictors in patients with solid malignancies: A systematic review and meta-analysis of 16 cohort studies.

We read with interest the article of Marra et al (1), who evaluated the short-term effectiveness of the COVID-19 mRNA vaccine in immunocompromised patients. They found that a reduced immune response to the COVID-19 mRNA vaccine was present in patients with solid organ transplant and malignant diseases compared to controls. Patients with solid malignancies are often immunocompromised, so we will further explore serological response to the COVID-19 vaccine in patients with solid malignancies.