Localized lumps in the middle of the suprasternal fossa may be boils, sebaceous cysts, lipomas and other diseases. 1. Boil: This disease is mainly caused by Staphylococcus aureus infection after damage to the hair follicles due to scratching and wiping of the skin, and can be triggered by factors such as decreased immunity, poor hygiene, sedentary behavior, and sweating. The skin lesions will appear red slightly elevated nodules, which can appear in any part of the body. 2. Sebaceous cysts: also known as acne, this disease occurs with the follicle sebaceous gland mouth blockage, resulting in sebum accumulation. Sebaceous cysts are found in the skin, and when present in the skin of the suprasternal fossa, they have a round shape and medium hardness. 3. Lipoma: It is a common benign soft tissue tumor composed of mature fat cells and can occur anywhere in the body where there is fat. Mainly in the subcutaneous, called superficial lipoma, in addition to localized lumps almost do not cause any symptoms, can be single or multiple. There are other causes of lumps in the middle of the suprasternal fossa (e.g., carbuncle, dermoid cyst), and it is recommended that the patient go to the hospital promptly to clarify the specific cause.