Collagen Tumor Capsules Break Open in Metastasis

There have been constant redefinitions of schirrhous response or the desmoplastic response in which the body encapsulates a tumor with collagen. Some would say that this was a negative prognostic, others that it was a good one. Certainly science has been confused as to the importance of "walling off" a tumor with collagen. It is not an imaginary computer graphics simulation, but a real phenomenon that is a biochemical reflex to turn an irritating mass into a benign one.

When metastasis occurs, these collagen capsules are broken open and the malignant cells spill outside, free to invade other tissues or the blood circulation. Clearly, the visual evidence suggests that the desmoplastic response is important to create a mechanical barrier, a wall, beyond which malignant tumor cells cannot pass. When these cells breach the wall, they have effectively begun to metastasize.

Tumor cell budding from focally disrupted tumor capsules: a common pathway for all breast cancer subtype derived invasion?