Another possibility that can explain the pain is pericarditis. It causes chest pain aggravated by laughing yawning and deep breathing and also causes radiation of pain to arms. Again an EKG, heat echo and chest X-ray is required. I think you should discuss these possibilities with your doctor.
Definition of atypiain medicine, atypia is an abnormality in cells tissue. If this is discovered at breast biopsy, removed 6 aug 2015 benign biopsies that show atypia indicate although the cells examined are not frankly malignant neither they entirely normal medical definition of atypism.
-plasia and -trophy. Anaplasia (structural differentiation loss within a cell or group of cells). Aplasia (organ or part of organ missing) Hypoplasia (congenital below-average number of cells, especially when inadequate) Hyperplasia (proliferation of cells) Neoplasia (abnormal proliferation) Dysplasia (change in cell or tissue phenotype)