A one centimeter thymoma is usually small in size and does not lead to significant clinical manifestations or dangerous conditions, but it should still be treated with timely surgery to remove the tumor. The cause of thymoma is not clear, but it may be related to radiation, chemical exposure, genetic factors, etc., which may cause the thymus gland to abnormally proliferate and form thymoma. Currently, most thymomas have the potential for malignant transformation, and some are malignant tumors in their own right, so even if they are slow-growing and have a low degree of malignancy, they should be treated in a timely manner. Generally speaking, a one-centimeter thymoma is usually small and does not cause obvious symptoms, and is mostly found by chance during physical examination. If not taken seriously in time, it may increase in size and cause compression symptoms, such as coughing, hoarseness, chest tightness, chest pain, palpitation, dyspnea and other manifestations; or accompanied by muscle weakness. It is recommended to consult a doctor when thymoma is found, and carry out active treatment, so as to avoid it leading to serious situations.