*2.2.3 Cell elements with a different morphology*

Cell elements having a different morphology were present in the tumor infiltrations in parallel with the predominant type (**Table 3**).

#### **Figure 1.**

*Cytological features of MALT lymphoma can range from small lymphocytic (b) morphology to monocytoid (a, c) morphology (hematoxylin–eosin, original magnifications ×400 [2].*


#### **Table 2.**

*MAL lymphoma: Cell element morphology of lymphoid infiltration with respect to three groups.*


#### **Table 3.**

*MALT-lymphoma: Morphological characteristics of lymphoid cell infiltration with respect to three groups.*

Monocytoid B-lymphocytes (35,2%). They were with a bean-shaped or irregular nuclei, wide and poorly stained cytoplasm.

Plasma cells (85,9%). In most cases plasma cells were located immediately under covering epithelium as a massive sheet (46.47%), or less frequently were dispersed in small portions in surface layers of gastric proper mucous plate among leukocytes

### *MALT Stomach Lymphomas: Aspects of Diagnosis and Treatment DOI: http://dx.doi.org/10.5772/intechopen.97865*

(39.43%). The plasma cells had typical appearance: nuclei, more frequently of a round or slightly irregular shape, wide cytoplasm in the form of a rim or a tongue of flame of intense pink color after Brachet staining.

Cells with plasmocytoid differentiation (21,13%). They resembled plasma cells, that was better observed after Brachet staining.

Lymphoepithelial lesions (LELs) as aggregations of 3 or more marginal zone cells destroying glandular epithelium were found in 50,7%. 6 cases (17.14%) presented with 'blast' LELs formed by large blasts (**Figure 2**).

Follicles or follicle-like structures with light-color proliferation centers consisting of centrocytes and centroblasts, a small number of mitotic figures and individual macrophages with cellular detrite in their cytoplasm were present in 14,09% cases. Proliferation centers could be surrounded by a partially preserved, thin mantle zone. Lymphoid follicle colonization when preexisting lymphoid follicle was replaced by small neoplastic cells was found practically in half the cases with follicles (15,49%).

Blasts. They were with either roundIoval/slightly irregular nuclei and 1 to 3 nucleoli, or with round bottle-shape nuclei and 1 compact, centrally located nucleolus. Amount of large blast cells varies from single cells to small group of cells (not more than 20 cells in one group).
