Christoph Johannes Szuszies

COVID-19 vaccines have become an integral element in the protection of cancer patients against SARS-CoV-2. To date, there are no direct comparisons of the course of COVID-19 infection in cancer patients between the pre- and post-vaccine era. We analyzed SARS-CoV-2 infections and their impact on cancer in COVID-19 vaccinated and non-vaccinated patients from three German cancer centers. Overall, 133 patients with SARS-CoV-2 were enrolled in pre- and post-vaccine eras: 84 non-vaccinated and 49 vaccinated, respectively. A mild course of COVID-19 was documented more frequently in vaccinated patients (49% vs. 29%), while the frequency of severe and critical courses occurred in approximately one-half of the non-vaccinated patients (22% vs. 42%, p = 0.023). Particularly, patients with hematologic neoplasms benefited from vaccination in this context (p = 0.031). Admissions to intermediate- and intensive-care units and the necessity of non-invasive and invasive respiratory support were reduced by 71% and 50% among vaccinated patients, respectively. The median length of admission was 11 days for non-vaccinated and 5 days for vaccinated patients (p = 0.002). COVID-19 mortality was reduced by 83% in vaccinated patients (p = 0.046). Finally, the median time from SARS-CoV-2 infection to restarting cancer therapy was 12 and 26 days among vaccinated and non-vaccinated groups, respectively (p = 0.002). Although this study does not have enough power to perform multivariate analyses to account for confounders, it provides data on COVID-19 in non-vaccinated and vaccinated cancer patients and illustrates the potential benefits of COVID-19 vaccines for these patients.

T-cell prolymphocytic leukemia is a rare aggressive malignancy with low susceptibility to conventional chemotherapy. The anti-CD52 antibody alemtuzumab induces remission, which requires consolidation by stem cell transplantation in eligible patients. In this case series, three chemotherapy-naïve T-PLL patients received alemtuzumab for remission induction and allogeneic SCT after reduced-intensity conditioning. While primary hematopoietic engraftment occurred in a timely fashion, donor chimerism declined in all patients between day 28 and day 290 post-transplantation. Loss of chimerism was not associated with disease recurrence, and full chimerisms were regained on donor leukocyte infusion. In six B-CLL patients, treated with identical regimens of alemtuzumab and SCT, a similar pattern of failing chimerism was not observed. We surmise that an accumulation of uncleared alemtuzumab in the plasma may impede the incoming graft after allogeneic SCT, which would indicate the need for close monitoring and management of engraftment to secure complete donor chimerism and putative cure in T-PLL patients.