Early on, these lesions are usually pretty thin, so it's called thin leukoplakia.

早期，这些病变往往较轻，因此可以将其称作薄白斑病。

At the cellular level, leukoplakia typically shows a thickened keratin layer.

从细胞学层面看，膜白斑的典型表是增厚的角质层。

These leukoplakias are usually painless but can't be easily scraped away.

这些白斑通常引起疼痛，但能被轻易刮去。

Now, the exact cause for leukoplakia is unknown, but a known risk factor is tobacco use.

我们还能明确膜白斑的致病因素，但有一个明确的高危因素：即烟草的使用。

These can either go away on their own, remain unchanged, or grow and become thicker, at which point it's called thick leukoplakia.

这类薄的白斑可能自行消失、保持原状或变厚；一旦变厚，就发展成了厚白斑病。

Signs of precancerous development include areas of leukoplakia, erythroplakia, erythroleukoplakia or any other abnormal appearing tissue or masses.

癌前征象包括膜白斑、红斑、红白斑或出其它正常的组织或肿块。

If it becomes bumpy it's called nodular leukoplakia, and if it becomes wart-like it's called verrucous leukoplakia.

如果白斑表面变得凹凸平，便称之为结节状膜白斑；如果白斑的形状像疣，则称其为疣状膜白斑。

Erythroplakias are more serious than leukoplakia because almost always when they are removed and examined under the microscope they will show severe dysplasia, or early cancer.

膜红斑要比膜白斑严重得多，因为显微镜下观察这些组织时，它们几乎都表出了明显的异型增生，或癌变早期征象。

However, leukoplakia is considered a precancerous condition, meaning that compared to normal tissue, it's more likely to develop into a cancer in the future.

但是，膜白斑被认为是一种癌前病变，意思是相对于正常组织来说，它未来发展成癌症的可能性更大。

Proliferative verrucous leukoplakia can turn into a particular type of squamous cell cancer called verrucous carcinoma, and it's also sometimes called snuff-dipper's cancer since it is more common among users of snuff and other forms of chewing tobacco.

增生性疣状白斑可发展成一种特殊的鳞状细胞癌，即疣状癌，有时也叫作“鼻烟”癌，因为这鼻烟和其它形式的嚼烟使用者中更常见。