DYSPLASIA IS DISORDERED GROWTH AND MATURATION OF THE CELLULAR COMPONENTS OF A TISSUE

异型增生是指组织细胞成分的无序生长和成熟

The cells that comprise an epithelium normally exhibit uniformity of size, shape and nuclear
structure.

构成上皮的细胞通常表现出大小、形状和核结构的一致性。

Moreover, they are arranged in a regular fashion, as, for example, a squamous epithelium
progresses from plump basal cells to flat superficial cells.

而且，它们规则排列，例如，鳞状上皮从饱满的基底层细胞演变为扁平的表层细胞。

In dysplasia, this monotonous appearance is disturbed by

(1) variation in cell size and shape;

(2) nuclear enlargement, irregularity and hyperchromatism

and (3) disarray in the arrangement of cells within the epithelium.

在异型增生中，这种单调的外观会受到以下因素的干扰：(1)细胞大小和形状的变化；(2)细胞核增大、不规则和深染；(3)上皮内细胞排列紊乱。

Dysplasia occurs most often in hyperplastic squamous epithelium, as seen in epidermal actinic keratosis (caused by sunlight) and in areas of squamous metaplasia, such as in the bronchus or the cervix.

异型增生最常见于增生性鳞状上皮，如表皮光化性角化病(由阳光引起)和鳞状化生区域，如支气管或宫颈。

It is not, however, exclusive to squamous epithelium. Ulcerative colitis, an inflammatory disease of the large intestine, is often complicated by dysplastic changes in the columnar mucosal cells.

然而，它并不是鳞状上皮所特有的。溃疡性结肠炎是一种大肠炎症性疾病，通常伴有柱状粘膜细胞的异常增殖性改变。

Like metaplasia, dysplasia is a response to a persistent injurious influence and will usually regress, for example, on cessation of smoking or the disappearance of human papillomavirus from the cervix.

与化生一样，异型增生是对持续的损害性影响的反应，通常会在例如戒烟或宫颈人乳头瘤病毒消失时消退。

 However, it shares many cytologic features with cancer, and the line between the two may be very fine.

然而，它与癌症有许多细胞学特征，两者之间的界限可能非常明确。

 For example, it may be difficult to distinguish severe dysplasia from early cancer of the cervix.

例如，可能很难区分重度不典型增生和早期宫颈癌。

Dysplasia is preneoplastic in the sense that it is a necessary stage in the multistep cellular evolution to cancer.

异型增生是癌前病变，从某种意义上说，它是细胞向癌症的多步进化的必要阶段。

 In fact, dysplasia is included in the morphologic classifications of the stages of intraepithelial neoplasia in various organs (e.g., cervix, prostate, bladder).

事实上，异型增生被包括在不同器官(如宫颈、前列腺、膀胱)上皮内瘤变的形态分类中。

Severe dysplasia is considered an indication for aggressive preventive therapy to cure the underlying cause, eliminate the noxious agent or surgically remove the offending tissue.

严重的不典型增生被认为是积极预防性治疗的指征，以治愈根本原因，消除有害因素或通过手术切除有害组织。

As in the development of cancer, dysplasia results from sequential mutations in a proliferating cell population. In other words , dysplasia is the morphologic expression of a molecular disturbance in growth regulation.

在癌症的发展过程中，异型增生是由增殖细胞群体中的顺序突变引起的。换句话说，异型增生是生长调节中分子紊乱的形态表现。

However, unlike cancer cells, dysplastic cells are not entirely autonomous, and with intervention, tissue appearance may still revert to normal.

然而，与癌细胞不同的是，发育不良的细胞并不是完全自主的，在干预下，组织外观仍可能恢复正常。