The study evaluate safety and effectiveness of chlorambucil and obinutuzumab in routine clinical practice in patients with chronic lymphatic leukemia and with certain comorbidities (any cardiac pathology, diabetes mellitus (DM), kidney pathology or cytopenia), whom obinutuzumab & chlorambucil have been applied according to indications before enrollment in the study.

MRD (Minimal residual disease) evaluation was chosen as a primary measure outcome as it is considered as prognostic marker for long-term progression freee survival (PFS) and as a potential therapeutic goal in chronic lymphocytic leukemia/ CLL .

Minimal residual disease (MRD-negative) is assessed in the clinic by 8-color flow cytometry giving the sensitivity level of MRD detection 10-5; MRD is measured in real clinical practice at this clinical center according to National recommendations in diagnostics and treatment of lymphoproliferative disorders.

To achieve study objectives medical patients' charts will be analyzed retrospectively. In the frame of this program 104 patients' charts treated in defined clinical site, are planned to be analyzed. This number of patients corresponds to the patient flow with this pathology at a defined clinical site for 1 years.

Data collection is considered to be retrospective as data will be transferred to e-CRF from patient medical charts. During this study no further specific extra procedures for data gathering is expected.

But since patients included in the study will be at the center of ongoing therapy, the study was called a prospective.

Inclusion Criteria:

1. CD20+/ (cluster of differentiation antigen 20 positive) B-CLL pts on the 1st line treatment therapy, whom have been already applied Obinutuzumab and chlorambucil
2. Age ≥ 18 years.
3. Eastern Cooperative Oncology Group Scale (ECOG) 0-2.
4. Total Chronic Illness Resources Survey scale (CIRS) score >6 or creatinine clearance <70 ml/min or both for patients ≥ 18 years old or all CLL pts ≥ 75 years old
5. Any cardiac pathology/ diabetes mellitus/ kidney pathology/ cytopenia (Hb <100 g/l, Platelets < 100 x 109/l)
6. Life expectancy more than 6 months according to the physician's opinion.
7. Signed informed consent that allow personal data and data that refer to patient confidentiality processing

Exclusion Criteria:

The refusal of the patient to participate in the observational study and the withdrawal of informed consent that allow processing of personal data and data that refer to patient confidentiality.

It is expected to include 104 patient with primary diagnosed CLL elder 18 years with certain comorbidities as any cardiac pathology/ diabetes mellitus/ kidney pathology/ cytopenia (Hb <100 g/l, Platelets < 100 x 109/l) after Obinutuzumab + chlorambucil are applied as the 1st line treatment .