**Immunophenotypic study in flow cytometry Method used direct immunofluorescence**

Antigens studied: CD19, CD 138, CD38, CD 56, chains kappa and lambda

Result

Mature lymphocytes = 20%

Clonal myeloma plasma cells: CD 138+ CD 38++CD19-CD56+ bright, CD 45 low with kappa clonal

restriction = 13%

#### **Table 4.**

*Phenotypic analysis on bone marrow blood.*

#### **Immunophenotypic study in flow cytometry Method used direct immunofluorescence**

Antigens studied: CD3, CD3/4, CD 3/CD8, CD19, CD16–56, CD117, CD 138, CD38, CD45, intracytoplasmatic chains kappa and lambda

Result

Mature lymphocytes = 60% Clonal myeloma plasma cells: CD 138+ CD 38-, CD56+, CD 45 + heterogeneous, cy kappa + = 10%

#### **Table 5.**

*Phenotypic analysis of pleural effusion.*


#### **Table 6.**

*Phenotypic analysis of pleural effusion.*

After one cycle of Dara Rd. therapy, for new reappearance of pleural effusion, the patient underwent thoracentesis, this time by performing the phenotypic analysis (**Table 5**).

While the plasma cells are absent for the reevaluation of the phenotypic study on peripheral blood, we continued the treatment until the fourth cycle.

After four cycles of therapy, we repeated PET/CT that was unfortunately compatible with persistence of disease.

The PET/CT showed persistence of a large area of hyperaccumulation of the tracer in coincidence of pathological tissue from D3 to L5 that incorporates the posterior mediastinal structures in its course.

Persistence of pathological accumulation in the anterior mediastinum, in the pleuro-pericardial region in increase compared to the previous examination, extending from the xiphoid to the anterior costophrenic recess, area of hyperaccumulation in the right parasternal and at the level of the mediastinal pleura close to the ascending aorta.

Despite the progression of disease, the CD38 negativity remained to the phenotypic reevaluation of the pleural fluid (**Table 6**).
