Among the four major types of carcinoma, large cell carcinoma is the easiest to detect because of its severe atypism
. We therefore concentrate on classification of the other three types--adenocarcinoma, squamous cell carcinoma, and small cell carcinoma--which are sometimes confused with each other in the cytological specimen.
Moreover, the histological differences between B-ca type and B-ad type lesions included nuclear atypism
or glandular distortion in the deeper mucosal layer, which were hardly observed under NBI-ME.
Microscopic evaluation of the resected specimen confirmed the diagnosis of GCT showing stromal cells with no appreciable atypism
. Occasional stromal cells showed large nuclei with abundant giant cells.
The defining histologic features of dysplastic colorectal epithelium in IBD are analogous to those of sporadic adenomatous polyps and include (1) nuclear atypism
manifested by increased nuclear to cytoplasmic ratios, crowding, and hyperchromasia; (2) cytoplasmic abnormalities suggesting altered differentiation and clonality, such as diminished or, conversely, excessive goblet cell mucin; and (3) abnormal growth patterns indicating faulty control of cellular proliferation, including glandular crowding, tubular or villiform architecture and the absence of normal base-to-surface epithelial maturation.
Degraded Rabbit At 28 months, focal (58) [lambda] (a,b,c) and severe glandular atypism
; precancerous changes seen.
Inoue, "Endoscopic diagnosis of tissue atypism
(EA) in the pharyngeal and esophageal squamous epithelium; IPCL pattern classification and ECA classification," Kyobu Geka, vol.
(6,7) However, because the incidence of nonleukemic dermatoses in leukemia patients is significantly higher than that of LC, it is difficult to make a specific diagnosis of LC when only a few leukemic infiltrates are present or leukemic cells display little atypism
. (1,8,9) Immunohistochemical markers are helpful in distinguishing leukemia cells from benign inflammatory cells of nonleukemic dermatosis in these situations.
In the study by Page et al, (3) papillary apocrine change lesions were confined to those cases that lacked nuclear atypism
. These lesions may be architecturally quite complex; however, they were uniformly characterized by "nuclear cytological pattern(s) as seen in usual apocrine change." On occasion, as the authors note, the degree of architectural complexity in PAC can be rather worrisome and associated with nuclear atypism
(1,2) Mitoses may be found, especially in areas of higher cellularity, but atypism
does not occur in benign lesions.
There was no nuclear enlargement, nuclear atypism
, immunoblasts, or serpiginous necrosis.
Intraepidermal poroma shows neither atypical cells nor an irregular epidermal pattern of growth. Clonal seborrheic keratosis shows well-defined epidermal nests of basaloid cells with distinct intercellular bridges, without atypia or mitoses. Bowen disease and squamous cell carcinoma arising in Bowen disease demonstrate a more pronounced atypism
of keratinocytes, dyskeratosis, and a severe architectural effacement.