Independent researcher.
Department of Medical Oncology, National Center for Cancer Care and Research, 36977Hamad Medical Corporation, Doha, Qatar.
Cancer Control. 2022 Jan-Dec;29:10732748221106266. doi: 10.1177/10732748221106266.
Coronavirus disease 2019 (COVID-19) infection is caused by severe acute respiratory syndrome coronavirus 2. Adults with cancer are immunocompromised due to several causes including cancer itself and immunosuppressive therapy. Thus, cancer patients are more susceptible to develop COVID-19 infection. As COVID-19 vaccines became available, patients with cancer would benefit from receiving the vaccine. This article aims to review the recent evidences and recommendations about COVID-19 vaccination in cancer patients.Current guidelines recommend that patients with cancer should have the priority to receive the vaccine given their immunocompromised state. The timing of administration varies depending on cancer type and treatment. Generally, the vaccine should be given before starting the chemotherapy if possible or in between chemotherapy cycles and away from nadir phase. For other cancer treatments, it is recommended to give the vaccine when there is evidence of blood count recovery. In general, induction therapy and treatment for newly diagnosed patients should not be delayed for the vaccination purpose. It is noteworthy to mention that cancer patients especially those with hematologic malignancies might have absented or attenuated response to the vaccine due to their pathophysiological status.On the other hand, the current vaccine guidelines have been criticized for lacking evidence on some important topics that need to be addressed. Firstly, some vaccines have been granted an emergency use authorization, prior to the usual comprehensive safety and efficacy evaluation process. Secondly, specific populations including cancer patients were excluded from the approval trials for safety reasons. Finally, some recommendations regarding the COVID-19 vaccines are extrapolated from other vaccines studies. Further studies are required to fill these gaps and observational studies that include cancer patients are warranted to have a better understanding of the safety and efficacy of the vaccines in cancer patients.
新型冠状病毒病（COVID-19）感染是由严重急性呼吸系统综合征冠状病毒 2 引起的。由于癌症本身和免疫抑制治疗等多种原因，癌症患者存在免疫功能低下。因此，癌症患者更容易发生 COVID-19 感染。随着 COVID-19 疫苗的问世，癌症患者将受益于接种疫苗。本文旨在综述癌症患者 COVID-19 疫苗接种的最新证据和建议。
目前的指南建议，鉴于癌症患者免疫功能低下，应优先接种疫苗。接种时间取决于癌症类型和治疗方法。一般来说，如果可能，化疗前或化疗周期之间且不在最低点时应接种疫苗。对于其他癌症治疗，建议在有血细胞计数恢复证据时接种疫苗。一般来说，不应为接种疫苗而延迟诱导治疗和新诊断患者的治疗。值得注意的是，由于生理病理状态，癌症患者，尤其是血液恶性肿瘤患者，可能对疫苗无反应或反应减弱。
另一方面，目前的疫苗指南因缺乏一些需要解决的重要问题的证据而受到批评。首先，一些疫苗在通常的全面安全性和疗效评估过程之前已获得紧急使用授权。其次，出于安全原因，一些特定人群，包括癌症患者，被排除在批准试验之外。最后，一些关于 COVID-19 疫苗的建议是从其他疫苗研究中推断出来的。需要进一步的研究来填补这些空白，并且需要包括癌症患者的观察性研究，以便更好地了解疫苗在癌症患者中的安全性和疗效。
