Single most likely diagnosis
- Hernia (inguinal or umbilical): This is the most common cause of a lump at the belt level, especially in adults. Hernias occur when part of an intestine or other tissue bulges through a weak spot in the abdominal wall.
Other Likely diagnoses
- Lipoma: A benign tumor composed of fat tissue, which can occur almost anywhere in the body, including the abdominal wall.
- Sebaceous cyst: A benign, usually painless, bump under the skin that can appear anywhere, including at the belt level.
- Abscess or infected cyst: An accumulation of pus that can form as a result of infection, which may present as a lump.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Incarcerated or strangulated hernia: A hernia that becomes trapped and its blood supply is cut off, which is a medical emergency.
- Abdominal wall tumor (e.g., desmoid tumor): Although rare, these tumors can be malignant and require prompt attention.
- Lymphoma: A type of cancer that can cause lymph nodes to swell, potentially forming a lump at the belt level.
Rare diagnoses
- Soft tissue sarcoma: A rare type of cancer that can occur in the abdominal wall, presenting as a lump.
- Endometrioma (in females): A cyst filled with old blood, occurring when endometrial tissue grows outside the uterus, potentially at the belt level.
- Neurofibroma: A benign tumor of the nerve tissue, which can occur anywhere, including the abdominal wall.