SARS-CoV-2 Serology Monitoring of a Cancer Center Staff in the Pandemic Most Infected Italian Region.

Since the beginning of the COVID-19 outbreak, Cancer Centers adopted specific procedures both to protect patients and to monitor the possible spread of SARS-CoV-2 among healthcare personnel (HCP). In April 2020 at Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, one of the three oncologic hubs in Lombardy where the Health Regional Authorities referred all the cancer patients of the region, we implemented a prospective longitudinal study aimed at monitoring the serological response to SARS-Cov-2 in HCP. One hundred and ten HCP answered a questionnaire and were screened by nasopharyngeal swabs as well as for IgM/IgG levels; seropositive HCPs were further screened every 40-45 days using SARS-CoV-2-specific serology. We identified a fraction of HCP with long-term anti-SARS-CoV-2 antibody responses, though negative for viral RNA, and thus probably able to safely approach fragile cancer patients. Monitoring asymptomatic HCP might provide useful information to organize the healthcare service in a Cancer Center, while waiting for the effectiveness of the active immunization by SARS-CoV-2 vaccines, which will provide protection from infection.

Peripheral blood stem cell collection in pediatric patients: feasibility of leukapheresis under anesthesia in uncompliant small children with solid tumors.

Leukapheresis demands patient's compliance and adequate vascular accesses, which can require invasive methods in very small children whose treatment protocol includes hemopoietic stem cell collection for myeloablative chemotherapy and stem cell rescue. Since 1998, at the Istituto Nazionale Tumori of Milan, in selected uncompliant small children, the placement of peripheral vascular accesses and leukapheresis have been performed at the same time under general anesthesia. Peripheral venous cannulas were positioned for blood collection, while blood was returned through either peripheral cannulas or mono-lumen central catheters previously installed for chemotherapy. A continuous-flow cell separator was used for leukapheresis. Between 1998 and 2003, 47 children with solid tumors underwent anesthesia for a total of 54 leukaphereses. The patients' age ranged from 12.7 to 93 months (median 30.3) and their weight ranged from 7 to 20 kg (median 14.1). Neither metabolic nor anesthesiological complications were recorded. In 89% of cases, the CD 34(+) cell target was achieved at a single harvest; the median number of CD 34(+) cells was 10.8 x 10(6)/kg/leukapheresis (range 1-117) and the median collection efficiency was 63.4% (range 25-100.6). Leukapheresis under anesthesia is feasible and safe in very low-weight children whose compliance is lacking due to age and disease.

B and C hepatitis viruses, HLA-DQ1 and -DR3 alleles and autoimmunity in patients with hepatocellular carcinoma.

BACKGROUND/AIMS: Hepatitis B and C involvement in hepatocellular carcinoma has been well established, but as yet not that of the human lymphocyte antigen (HLA) complex. To study viral, HLA and tumour interrelationships, 105 patients were evaluated for prevalence of viral markers and 161 patients, including 99 of the previous ones, for HLA allele frequency; the other 52 patients served as controls. METHODS: Immunoassays, molecular assays, microlymphocytotoxicity. RESULTS: Positivity for hepatitis B surface antigen and/or hepatitis C antibodies in 89% cirrhotic, 44% non-cirrhotic vs. 92% control patients (cirrhotic; all hepatitis C antibody positives were viraemic). Recurrent HLA alleles: HLA-Cw7 and -DQ1 in cirrhotic and control patients, HLA-Cw7, -B8 and -DR3 in non-cirrhotic patients compared with healthy controls (Pc=0.0000074, 0.000025, 0.0025, 0.00027 and 0.043, respectively). CONCLUSIONS: Viral data suggest a high chronic infection rate for cirrhotic patients. Recurrent HLA-Cw7 is compatible with natural killer cell activity inhibition to virus-infected and tumour cells by HLA C molecules. Recurrent HLA-DQ1 and -DR3 suggest the existence of an autoimmune condition with cell destruction in cirrhotic and without cell destruction in non-cirrhotic patients as a consequence of autoreactive DQ-restricted T-helper (Th)1 and DR-restricted Th2 cells response, respectively. HLA-B8-DR3 linkage disequilibrium was possible. Thus, autoimmunity may have contributed to hepatocellular carcinoma development in these patients.