According to a recent study published in Cancer, less than half of patients with hematologic malignancies developed detectable antibodies after the initial COVID-19 vaccination, but 56% of "nonresponders" developed antibodies after receiving a booster dose.

Dr. Thomas Ollila, MD, of Brown University, and his colleagues conducted a retrospective study to analyze the antibody response to initial and booster COVID-19 vaccination in patients with hematologic malignancies. In the study, they found anti-SARS-CoV-2 antibodies in the blood sample of 48% of the patients after initial vaccination with one of three U.S. Food and Drug Administration -authorized or approved COVID-19 vaccines.

On the other hand, patients who did not have any antibody response after initial vaccination were observed to have an antibody response after taking a booster dose. 56% of the patients showed an antibody response, following a booster shot. Dr. Ollila concluded that many of the patients who did not respond initially to the vaccination will have a response to the booster vaccination. He also added that while comparing the outcomes, it was found that deaths from COVID-19 in the patient population occurred in people with undetectable antibodies. In view of this, he emphasized the importance of booster vaccines for cancer patients to reduce the risk of mortality. 

(Source: https://www.hindustantimes.com/lifestyle/health/blood-cancer-patients-respond-to-booster-dose-of-covid-19-vaccination-rather-than-first-dose-study-101657626728814.html )