A hiatal hernia – a rarer cause of pain under your left breast—is when your upper stomach bulges through the diaphragm, which separates your abdomen and chest, per Mayo Clinic. The painful sensation ...
Pulmonary fibrosis is a disease where there is scarring of the lungs—called fibrosis—which makes it difficult to breathe. This is because the scarring causes the tissues in the lungs to get thick and ...