According to the Mayo Clinic, pea-sized lumps in the armpit are a symptom of hidradenitis suppurativa, a condition in which the hair follicles become blocked. The cause of hidradenitis suppurativa is unknown, but the con... More »

A hard, pea-sized lump in the armpit is usually a swollen lymph node. The lump can appear especially when a person is already experiencing an illness or symptoms of an infection. The glands under the armpit tend to swell... More »

An ache in the armpit may indicate the presence of an abscess, which is a tender, fluid-filled lump caused by the body's inflammatory response, states WebMD. Other causes of aches in the armpit include swollen lymph node... More » Health

Prurigo nodularis is a health condition that causes itchy, hard and crusty lumps to develop on the surface of the skin, as stated by the American Osteopathic College of Dermatology. Itching caused by prurigo nodularis ca... More » Health Conditions & Diseases

A doctor may diagnose a patient with a pancreatic mass after detecting a lump in the upper abdominal area, which is where the pancreas is located, notes WebMD. A mass is a term used to describe an abnormal growth in the ... More » Health Conditions & Diseases

Depending on the patient's age, a lump on the right clavicle likely means an infected lymph node, a congenital lesion or a neoplastic lesion that may or may not indicate cancer, states Priory Medical Journals. In cases o... More » Health Conditions & Diseases

A lump on the right side below the rib cage is a possible sign of adult primary liver cancer, according to WebMD. A swelling of the liver causes the lump and other symptoms. More »