Poorly differentiated sarcoma

Cancer diseases have become very common in recent years, among which sarcoma is a relatively common tumor disease. In the development process of sarcoma, there are two types: poorly differentiated and well differentiated. Poorly differentiated sarcoma is a more serious development. Since this disease poses a great threat to human life safety, everyone is more concerned about its treatment methods. However, let us first understand what poorly differentiated sarcoma is.

Differentiation refers to the process of gradual development from immature cells in the embryo to mature normal cells. Tumor cell differentiation The so-called degree of tumor cell differentiation refers to the degree to which tumor cells are close to normal cells. Pathologists make judgments based on the differences in tumor cells after HE staining under a microscope. Most grading systems classify tumors into 3 or 4 grades of differentiation.

The better the differentiation (called "high differentiation"), the closer the tumor cells are to the corresponding normal tissue of origin; and the less differentiated cells (called "poorly differentiated" or "undifferentiated") are more different from the corresponding normal tissue of origin, and the more malignant the tumor is. Given that the difference between the two is called "intermediate differentiation".

According to the degree of tumor differentiation, pathologists usually divide tumor cells into four pathological grades, represented by the English letter G (standing for Grade: differentiation). A higher grade indicates a less differentiated cell.

Grade definition

Grade I (G1) means highly differentiated, with a good degree of cell differentiation. Generally speaking, tumor cells in G1 divide more slowly.

Grade II (G2) is moderately differentiated, with a moderate degree of cell differentiation.

Grade III (G3) is poorly differentiated, with poor cell differentiation.

Grade IV (G4) Undifferentiated

Lung cancer grading is mostly used for squamous cell carcinoma and adenocarcinoma. It is generally divided into three levels: Level I is well differentiated (also known as high differentiation), Level II is moderately differentiated (also known as moderate differentiation), and Level III is poorly differentiated (also known as low differentiation).

Squamous cell carcinoma grade I: Cancer cells are arranged in layers, with obvious keratinized beads and intracellular keratinization in the cancer nests, and well-developed intercellular bridges (intercellular bridges: direct connection of the cytoplasm between adjacent cells, such as the intercellular bridges between daughter cells when the cytoplasm of spermatogonia and spermatids is not completely disconnected. It can be used as one of the diagnostic markers for malignant tumors.).

Squamous cell carcinoma grade II: The boundaries of cancer cells are clear, the nuclei around the cancer nests are arranged in a palisade pattern, and there is intracellular keratinization and individual keratinized beads.

Squamous cell carcinoma grade III: Cancer cells vary in size, intercellular bridges are not obvious, nuclear atypia is obvious, and nuclear division is often accompanied by necrosis.

Adenocarcinoma grade I: The glandular epithelium is arranged in tubular, papillary, or alveolar shapes, with no obvious cell atypia and rare nuclear division.

Adenocarcinoma grade III: Tumor cells are arranged in sheets or solid forms, with only focal glandular structures or mucus secretions, obvious cell atypia, frequent nuclear divisions, and obvious necrosis.

Adenocarcinoma grade II: between the two. The grading criteria for adenosquamous carcinoma are the same as above.

Typical carcinoids are well differentiated, while atypical carcinoids are moderately or well differentiated.

Most salivary gland carcinomas are well differentiated, and a few are moderately differentiated.

Small cell carcinoma, large cell carcinoma, and carcinoma with pleomorphic, sarcomatoid, or sarcomatous components are poorly differentiated.

It should be pointed out that good, moderate and poor differentiation is only an artificial standard. Differently differentiated tumors may appear in the same lesion or the same section of lung cancer. For patients with the same clinical stage, the degree of differentiation often affects the patient's prognosis.

For different tumors, the degree of differentiation of tumor cells and the patient's prognosis are not necessarily directly related. From a treatment perspective, certain poorly differentiated cells are more sensitive to chemotherapy and radiotherapy. In other words, the less differentiated the tumor is, the easier it is to treat with chemotherapy and radiotherapy. Therefore, not all well-differentiated tumors have a better prognosis than poorly differentiated tumors.

For example, lymphoma is a common blood disease. The cure rate of some medium-to-high-differentiated lymphomas can reach about 40% through the combined treatment of chemotherapy and radiotherapy. For most chronic lymphomas (poorly differentiated), the progression of the disease is often very slow and may last for several years or even more than ten years, but drug therapy has almost no curative effect on chronic lymphoma. Similar situations also occur in the diagnosis and treatment of nasopharyngeal carcinoma. For example, in the case of oral or pharyngeal squamous cell carcinoma, there is no direct correlation between the degree of differentiation of tumor cells and the patient's prognosis.

In short, the degree of cell differentiation has different meanings for different tumors. The degree of differentiation of tumor cells is an important reference data in cancer diagnosis and treatment, but the effectiveness of treatment still needs to be comprehensively judged based on the type, stage, and treatment method of the cancer.