T‐Cell Response After SARS ‐ CoV ‐2 Vaccination in Patients With Hematological Malignancy

ABSTRACT Patients with hematologic malignancies (HM) often mount poor humoral responses to SARS‐CoV‐2 vaccination due to their immunocompromised status. Protection against severe COVID‐19 is strongly related to cellular immunity, yet vaccine‐induced T‐cell responses remain incompletely characterized. We conducted a systematic review of 87 studies assessing vaccine‐induced T‐cell response rates in HM. Across HM subtypes, 75%–87% of studies reported T‐cell response rates of at least 50%. Active disease was associated with reduced T‐cell responses. These findings indicate that SARS‐CoV‐2 vaccination can elicit cellular immunity in HM patients, including those receiving immunosuppressive therapy, supporting continued vaccination strategies even when humoral responses are suboptimal.