Merkel cell carcinoma
Introduction
Introduction to Merkel Cell Carcinoma Merkel cell carcinoma is also known as cutaneous trabecular carcinoma, primary cutaneous neuroendocrine carcinoma, primary small cell carcinoma of the skin, and skin APUD. First reported by Toker in 1972. The latest study found that about 80% of Merkel's cell carcinoma is associated with Meckel's cellular polyomavirus infection, and 20% of Merkel's cell carcinoma has no Merkel cell virus infection, suggesting that Merkel's cell carcinoma has other causes. Disease factor. basic knowledge The proportion of illness: the incidence rate is about 0.0004%-0.0006% Susceptible people: common in the elderly Mode of infection: non-infectious Complications: hair epithelioma
Cause
Merkel cell carcinoma cause
(1) Causes of the disease
The etiology of this disease is not clear, and may have certain correlation with environmental factors, genetic factors, dietary factors, and mood and nutrition during pregnancy.
(two) pathogenesis
The pathogenesis is still unclear. Pathological features: The tumor consists of round, oval cells with uniform size and shape. Located in the dermis, it often infiltrates subcutaneous tissue, sarcolemma and muscle. The cell size is about 2 to 3 times that of mature lymphocytes, the nucleus is oval, the chromatin is fine and scattered, and the nuclear membrane is obvious.
Prevention
Merkel Cell Cancer Prevention
Pay attention to the hygiene of the affected area, wash the vulva with warm water every day, change the underwear frequently, and avoid the chronic long-term stimulation of the secretions. Found that the vulva has nodules, ulcers and papillary masses, or white lesions in the vulva, etc., should go to the hospital in time to rule out the possibility of vulvar cancer, and actively treat, so that the condition is controlled. Middle-aged and elderly women should be regularly gynecologically surveyed, and some chronic vulvar diseases, such as leukoplakia and vulvar papilloma, which may be converted into vulvar cancer, should be treated promptly and thoroughly, which can greatly reduce the incidence of cancer.
Complication
Merkel cell carcinoma complications Complications, epithelial tumors
Many hair styles are autosomal dominant inheritance, which is common in women and occurs in childhood. The rash is distributed symmetrically along the nasolabial fold and can also occur in the nose, forehead, eyelids, and upper lip. The damage diameter is between 2 and 10 mm. It is a hemispherical transparent small nodule with a smooth surface and a firm texture, ranging from ten to several hundred. Small lesions can fuse into larger nodules. Capillary dilatation is sometimes seen. The damage can last for several years without any symptoms.
Symptom
Merkel cell cancer symptoms common symptoms nodules
The tumor is solid, dome-shaped, red or purple nodules, often growing rapidly, common in the exposed skin of elderly patients, the average age of onset is 68 years old, more women than men, the primary affected part is the head and neck Department (44%), leg (28%), buttocks (9%), arms (16%), uncommon parts, such as scrotum and female genital, local recurrence rate of 26% to 44%, nearby lymph node metastasis For 53%, the distant metastasis was 75%, resulting in a mortality rate (5-year survival rate) of 30% to 64%, and the prognosis was worse than malignant melanoma.
Examine
Merkel cell carcinoma examination
Histopathology: The tumor consists of a circular shape with uniform size and shape, consisting of oval cells, located in the dermis, often infiltrating the subcutaneous tissue, sarcolemma and muscle. The cell size is about 2 to 3 times that of mature lymphocytes. Round, chromatin is small and scattered, the nuclear membrane is obvious, the nucleolus is usually not obvious, the cytoplasm is sparse, and a large number of mitotic figures are visible. The edge of the tumor is characterized by infiltrative trabeculae, common necrosis areas, individual cell necrosis and characteristics. Sexually comminuted artificial product, adjacent to the matrix fibrosis, vascular rich and lymphocyte plasma cell infiltration.
Low molecular weight cytokeratin staining can demonstrate a characteristic nucleus-like globular response, and cells often express epithelial membrane antigens. In addition, various neuroendocrine markers include chromogranin, synaptophysin, and growth hormone release inhibition. Factors such as somatostatin, calcitonin, and vasoactive intestinal peptides are positive, and this tumor is also positive for neuron-specific enolase, but is characteristically negative for S-100 protein. .
Diagnosis
Merck's cell carcinoma diagnosis and differentiation
Histology still needs to be differentiated from malignant lymphoma, small cell melanoma, sweat adenocarcinoma, neuroblastoma, Ewing tumor, and vascular epithelioid sarcoma. Pathologically, because the size of the tumor cells is consistent and immature, it is easily misdiagnosed as a mother cell lymphoma or metastatic carcinoma, especially oat cell carcinoma derived from the lung. The latter also contains dense particles in the tumor cells, so it is necessary Electron microscopy can be used to identify.
