The dermis, the skin's next layer, is a thick layer of fibrous and elastic tissue (made mostly of collagen, with a small but important component of elastin) that gives the skin its flexibility and strength. The dermis contains nerve endings, sweat glands and oil (sebaceous) glands, hair follicles, and blood vessels.
âAll cancers are caused by genetic mutations, and in some cases we know the processes driving them, for example, tobacco smoking in lung cancer, however, our understanding of the causes of mutation in most cancers is remarkably limited,â Grimmond says.
Tumors are also caused due to external sources like carcinogen. Tobacco and alcohol are some of the causes of tumor. Benign Tumor. A benign tumor is a lump of dead cells which causes a mound in the part they are located and remains rooted at a place causing discomfort only to that specific part of the body. These dead cells do not give way to healthier cells for replacement.