Sarcoma in the mouth of the average person often refers to a tumor that grows on the flesh of the body, and it is not necessary to distinguish between benign and malignant. In fact, the medical term sarcoma refers to a malignant tumor originating from human interstitial tissue. What is mesenchymal tissue? Mesenchymal tissue is a general term for the tissues differentiated and developed from mesoderm mesenchyme during embryonic development, such as connective tissue, adipose tissue, vascular tissue, bone and cartilage tissue, mucous tissue, lymphoid tissue, striated muscle and smooth muscle tissue, synovium and so on. Therefore, sarcoma is a general term for a large class of malignant tumors, including liposarcoma, leiomyosarcoma, rhabdomyosarcoma, osteosarcoma, chondrosarcoma and fibrosarcoma. So in medical terms, sarcoma must be malignant.

Sarcoma does not belong to cancer. According to the pathological classification of malignant tumors, those from epithelial tissue belong to cancer and those from mesenchymal tissue belong to sarcoma. Cancer and sarcoma are juxtaposed. Compared with cancer, sarcoma is relatively rare and more common in teenagers. Cancer is more common, the incidence rate is about 9 times that of sarcoma, and it is more common in adults over 40 years old. Generally speaking, cancer is hard, gray and dry, while sarcoma is soft, gray-red, moist and fishy. From the perspective of metastasis, cancer usually metastasizes through lymphatic channels in the early stage, and sarcoma usually metastasizes through blood channels. Surgical treatment is still the main treatment for sarcoma. Some sarcomas are sensitive to radiotherapy and chemotherapy, such as osteosarcoma, but others are not sensitive to radiotherapy and chemotherapy, such as liposarcoma. However, because sarcoma is easy to metastasize to other organs, especially lung metastasis, the prognosis is generally poor. Prognosis still depends on early detection.

Malignant tumor from epithelial tissue is called cancer, and the most common epithelium is skin, so there is skin cancer. In addition, the surfaces of hollow organs are covered by epithelium, such as esophagus, stomach, intestine and bronchus. Therefore, the occurrence of lung cancer is bronchial and alveolar mucosal epithelium, while the occurrence of esophageal cancer comes from esophageal mucosal epithelium. Figuratively speaking, a grapefruit, grapefruit skin is equivalent to epithelial tissue, grapefruit meat inside is equivalent to interstitial tissue, and fat belongs to interstitial tissue, so the malignant tumor of fat is called liposarcoma, not liposarcoma.

There is also a malignant tumor in clinic, called sarcomatoid carcinoma. Its essence is epithelial carcinoma and sarcomatoid components. It is not a real sarcoma, but a cancer with spindle cell variation. These so-called sarcomatoid spindle cells are essentially cancer cells that differentiate into sarcomatoid cells. For example, sarcomatoid carcinoma of lung is a small cell lung cancer with sarcomatoid cells and sarcomatoid differentiation. This type is relatively rare in clinic, accounting for about 2% ~ 3% of lung malignant tumors. It is relatively aggressive and has a high degree of malignancy. This is more common among men with a heavy smoking history. Not sensitive to radiotherapy and chemotherapy, poor prognosis.