Efficacy of mRNA anti-SARS-CoV-2 vaccination and dynamics of humoral immune response in patients with solid tumors: results from the institutional registry of an Italian tertiary cancer center.

Background: Systemic immunosuppression characterizing cancer patients represents a concern regarding the efficacy of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, and real-world evidence is needed to define the efficacy and the dynamics of humoral immune response to mRNA-based anti-SARS-CoV-2 vaccines. Methods: We conducted an observational study that included patients with solid tumors who were candidates for mRNA anti-SARS-CoV-2 vaccination at the Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy. The primary objective was to monitor the immunologic response to the mRNA anti-SARS-CoV-2 vaccination in terms of anti-spike antibody levels. All the patients received two doses of the mRNA-1273 vaccine or the BNT162b2 vaccine. Healthcare workers served as a control group of healthy subjects. Results: Among the 243 patients included in the present analysis, 208 (85.60%) and 238 (97.94%) resulted seroconverted after the first and the second dose of vaccine, respectively. Only five patients (2.06%) had a negative titer after the second dose. No significant differences in the rate of seroconversion after two vaccine doses were observed in patients as compared with the control group of healthy subjects. Age and anticancer treatment class had an independent impact on the antibody titer after the second dose of vaccination. In a subgroup of 171 patients with available data about the third timepoint, patients receiving immunotherapy with immune checkpoint inhibitors seem to have a higher peak of antibodies soon after the second dose (3 weeks after), but a more pronounced decrease at a late timepoint (3 months after). Conclusions: The systemic immunosuppression characterizing cancer patients did not seem to dramatically affect the humoral response to anti-SARS-CoV-2 mRNA vaccines in our population of patients with solid tumors. Further investigation is needed to dissect the interplay between immunotherapy and longitudinal dynamics of humoral response to mRNA vaccines, as well as to analyze the cellular response to mRNA vaccines in cancer patients.

COVID-19 risk for patients undergoing anticancer treatment at the outpatient clinic of the National Cancer Institute of Milan: the COVINT study.

BACKGROUND: In the midst of the COVID-19 pandemic, patients with cancer are regarded as a highly vulnerable population. Overall, those requiring hospital admission for treatment administration are potentially exposed to a higher risk of infection and worse outcome given the multiple in-hospital exposures and the treatment immunosuppressive effects. METHODS: COVINT is an observational study assessing COVID-19 incidence among patients receiving anticancer treatment in the outpatient clinic of the Istituto Nazionale dei Tumori di Milano. All consecutive patients with non-haematological malignancies treated with intravenous or subcutaneous/intramuscular anticancer therapy in the outpatient clinic were enrolled. The primary endpoint is the rate of occurrence of COVID-19. Secondary endpoints included the rate of COVID-19-related deaths and treatment interruptions. The association between clinical and biological characteristics and COVID-19 occurrence is also evaluated. COVID-19 diagnosis is defined as (1) certain if confirmed by reverse transcriptase PCR assay of nasopharyngeal swabs (NPS); (2) suspected in case of new symptoms or CT scan evidence of interstitial pneumonia with negative/not performed NPS; (3) negative in case of neither symptoms nor radiological evidence. RESULTS: In the first 2 months (16 February-10 April 2020) of observation, 1081 patients were included. Of these, 11 (1%) were confirmed and 73 (6.7%) suspected for COVID-19. No significant differences in terms of cancer and treatment type emerged between the three subgroups. Prophylactic use of myeloid growth factors was adopted in 5.3%, 2.7% and 0% of COVID-19-free, COVID-19-suspected and COVID-19-confirmed patients (p=0.003). Overall, 96 (8.9%) patients delayed treatment as a precaution for the pandemic. Among the 11 confirmed cases, 6 (55%) died of COVID-19 complications, and anticancer treatment was restarted in only one. CONCLUSIONS: During the pandemic peak, accurate protective measures successfully resulted in low rates of COVID-19 diagnosis, although with high lethality. Prospective patients' surveillance will continue with NPS and serology testing to provide a more comprehensive epidemiological picture, a biological insight on the impact of cytotoxic treatments on the immune response, and to protect patients and healthcare workers.

Systemic Treatment of Patients With Gastrointestinal Cancers During the COVID-19 Outbreak: COVID-19-adapted Recommendations of the National Cancer Institute of Milan.

The current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak poses a major challenge in the treatment decision-making of patients with cancer, who may be at higher risk of developing a severe and deadly SARS-CoV-2 infection compared with the general population. The health care emergency is forcing the reshaping of the daily assessment between risks and benefits expected from the administration of immune-suppressive and potentially toxic treatments. To guide our clinical decisions at the National Cancer Institute of Milan (Lombardy region, the epicenter of the outbreak in Italy), we formulated Coronavirus-adapted institutional recommendations for the systemic treatment of patients with gastrointestinal cancers. Here, we describe how our daily clinical practice has changed due to the pandemic outbreak, with the aim of providing useful suggestions for physicians that are facing the same challenges worldwide.