A National, Multicentric, Observational, Prospective Study to Assess Immune Response to COVID-19 Vaccine in Frail Patients (VAX4FRAIL).

1a. Newly diagnosed patients with ANY haematological malignancy requiring treatment (No.=100).

1b. Patients with ongoing treatments or with treatments completed within 6 months (chemotherapy and target therapies) other than antibodies. More specifically: patients with ongoing or completed chemotherapy (No.=50) or patients with ongoing or completed Ibrutinib (No.=50) or patients with ongoing or completed ruxolitinib (No.=50)

1c. Patients treated with anti-CD19 or CD20 or CD22 or CD30 or anti-PD1 antibodies with or without chemotherapy OR patients receiving CAR-T cells: patients treated anti-B-cell (No.=50) or patients treated anti-CD30 (No.=50) or patients treated anti-PD1 (No.=50).

1d. Patients at three months after autologous or allogeneic transplantation without active immune suppressive therapy: after autologous transplantation (No.=50) or after allogenic transplantation (No.=50).

2a. Chemotherapy in adjuvant therapy. All patients with a diagnosis of solid tumors apart resected basal-cell or squamous-cell carcinoma of the skin, melanoma in situ, carcinoma in situ of the cervix, and carcinoma in situ of the Breast. Under curative surgery (stage II-III) for the solid tumor or hemotherapy alone or in combination with target therapies or radiotherapy (No.=100).

2b. Chemotherapy in metastatic Disease. All patients with a diagnosis of solid tumors with Metastatic disease (stage IV), undergoing chemotherapy alone or in combination with immunotherapy or target therapy (No.=100).

2c. Immunotherapy in metastatic Disease. All patients with a diagnosis of solid tumors with Metastatic disease (stage IV), undergoing immunotherapy alone (No.=100).

2d. Target therapies in metastatic Disease. All patients with a diagnosis of solid tumors with Metastatic disease (stage IV), Undergoing target therapy alone (No.=100)

3a. Patients with ANCA-associated vasculitis classified according to Chapel Hill Consensus Conference nomenclature, treated with immunodepressants agents with/without glucocorticoids (No.=50) or treated with RTX with/without glucocorticoids (No.=50) 3b. Interstitial Lung Disease in Autoimmune Conditions. Patients with a diagnosis of a specific CTD, myositis or rheumatoid arthritis based on validated classification criteria, and clinically significant ILD defined as disease treated with traditional immunodepressants or rituximab and fibrotic and/or inflammatory changes on chest CT not attributable to infection, and no evidence of obstructive lung disease. Patients treated with traditional immunodepressive agents with/without glucocorticoidspatients (No.=50) or patients treated with rituximab with/without glucocorticoids (No.=50)

4a. Patients with a diagnosis of multiple sclerosis, age < 60 years with relapsing-remitting MS on Ocrelizumab (anti-CD20 monoclonal antibody) (No.=50) or with secondary/primary progressive MS on Ocrelizumab (anti-CD20 monoclonal antibody) (No.=50).

4b. Generalized Myasthenia Gravis, on immunosuppressive polytherapies or on B-cell targeted biological treatments, with lymphocytes count < 1 cell/microliter, or with thymoma (No.=100)