mRNA COVID-19 Vaccines Safe Among Patients With Cancer History

Equivalent safety outcomes of vaccination against SARS-CoV-2, the virus that causes COVID-19, were found among individuals receiving care at Fox Chase Cancer Center who had a history of cancer and those currently undergoing treatment, reports Journal of the National Comprehensive Cancer Network.

In connection with first and second vaccination doses with BNT162b2 from Pfizer, data were compared for 3 outcomes among 1753 patients at Fox Chase: measure of short-term adverse events (AEs) among patients with cancer, comparison of the degree/extent of AEs between the active-treatment and cancer-history cohorts, and relation, or not, to active cancer treatment. The study window was February 16, 2021, to May 15, 2021.

“Before this study, there wasn’t a lot of data specifically on the cancer population, so we made sure to collect and report this information to help both patients and physicians make informed decisions to get mRNA vaccines,” said lead researcher Eric M. Horwitz, MD, FABS, FASTRO, in a statement. Horwitz is Department of Radiation Oncology chair at Lewis Katz School of Medicine at Temple University in Philadelphia, Pennsylvania.

All study participants received their vaccine doses 3 weeks apart in the study window and were given 2 surveys: an in-person survey when they returned for their second vaccine dose and an online or telephone survey 2 weeks after their second dose. Among the 1183 persons with a history of cancer who responded to both surveys, 210 were on active treatment (24.2%, surgery; 18.0%, radiation; 39.8%, chemotherapy; 26.0%, other systemic therapy [16.6%, immunotherapy; 24.2%, targeted therapy; 59.2%, hormone therapy]). Of the patients with cancer, 92.5% had a solid malignancy and 7.5% a hematologic malignancy.

Localized injection-site reaction was the most common AE after the first dose and the second dose for those with no history of cancer compared with persons with a cancer history: 39.3% vs 43.9% (P = .07), respectively. A similar result was seen for the second dose, at 42.5% vs 40.3% (P = .45).

Slight differences were seen among the cancer cohort, however, when considering injection site pain after the first dose. Being on active treatment was less likely to result in injection-site pain (30.0%) compared with not receiving active treatment (41.1%; P = .002). Active treatment, however, was shown to not be an influential factor for both AE onset and duration, with patients receiving immunotherapy having AEs similar to what was seen among the general population.

Overall, the percentages of both groups reporting postvaccination symptoms were close to equal, at 73.3% and 72.5% (P = .71) in patients with and without cancer, respectively.

Additional findings reveal the following:

• 61.3% of patients with cancer reported an AE after the first vaccine dose vs 60.2% of those without cancer
• 64.2% and 62.8%, respectively, reported AEs after the second dose
• 63.7% vs 60.2% reported at least 1 AE after the second dose
• 16.5% vs 11.9% reported muscle pain after dose 1
• 10.2% and 9.8% reported postvaccination symptoms extending beyond 5 days
• 77.8% of women vs 65.5% of men reported postvaccination symptoms
• 84.4% of participants aged 18 to 59 years vs 72.2% of those aged 60 to 79 years and 50.0% of persons 80 years and older reported postvaccination symptoms
• Fatigue, joint pain, fever, chills, headaches, and nausea were more common in patients with cancer following the second dose

The authors initiated this study because the reported mortality rate of COVID-19 is 3 times higher among patients with cancer compared with people who do not have cancer, because most pilot investigations of SARS-CoV-2 vaccines did not include patients with cancer or their follow-up, and because patients with cancer have stricter isolation protocols.

An important question about of mRNA vaccines that the authors wanted to investigate for patients with cancer was whether this vaccine type could alter tumor biology, due to already knowing that lysosomal particles accumulate in many solid tumors, which itself might interfere with the body’s immune response to the vaccine. They also wanted to address vaccine hesitancy among patients with cancer.

“This is the largest published study to date examining the short-term AEs of COVID-19 vaccination in patients with cancer and the potential impact of active cancer treatment on such effects,” the authors wrote.

There are several important strengths to their data, including that they show an mRNA vaccine can be well tolerated by patients with a history of cancer and those undergoing treatment, that AEs are similar vs persons without cancer, and that these vaccines can be delivered in a timely manner. However, because of their study only investigating short-term AEs, their small patient population, and limiting their investigation to the Pfizer COVID-19 vaccine, the generalizability of their findings is limited

“Future studies of vaccination for COVID-19 involving patients with cancer will need to address possible rare and long-term AEs in this population, assess the durability of the vaccine-mediated immune response, and determine the impact, if any, of the vaccine on cancer treatments,” the authors concluded.

Reference

Shulman RM, Weinberg DS, Ross EA, et al. Adverse events reported by patients with cancer after administration of a 2-dose mRNA COVID-19 vaccine. J Natl Comp Canc Netw. 2022;20(2):1-7. doi:10.6004/jnccn.2021.7113