Costochondritis is a spontaneous pain that occurs near the connection of the rib cartilage to the sternum. It is mostly seen in young women. The clinical manifestations are pain in the anterior chest, mostly soreness and swelling, with a sharp or slow onset, sometimes light and sometimes heavy, aggravated by turning and coughing, deep breathing, upper limb activity, sometimes radiating to the upper limbs, and pressure pain at the 2-5 rib cartilage if not treated promptly and thoroughly, with a tendency to recur. Diagnostic points: 1. The only symptom is localized pain, sometimes radiating to the shoulder or back, but the most obvious pain is mostly at the outer edge of the sternum. The pain is more common in the 2nd and 3rd rib cartilage and is aggravated by coughing and upper limb activity; 2. Examination may reveal swelling, elevation and pressure pain in the affected rib cartilage. According to your description, there is a lump and it is related to diet, you should first do abdominal ultrasound or CT and other examinations to exclude abdominal organic lesions. Then the diagnosis of costochondritis should be considered. Principles of treatment of costochondritis: 1. symptomatic treatment, local medication, taking pain medication, can add prednisone anti-inflammatory and pain relief; 2. antiviral medication; 3. local injection of local anesthetics and hormones.