This case illustrates typical features of extraosseous multiple myeloma. This patient was diagnosed with multiple myeloma 3 years ago, presented with a slowly enlarging lump in the right pectoral area several months ago. Histopathology has confirmed the diagnosis. 

Extraosseous multiple myeloma is an uncommon form of multiple myeloma which found in less than 5% of myeloma patients. It can be also encountered in various part of the body such as the gastrointestinal tract, lymph nodes, spleen, parotid gland, vagina, breast, pancreas, thyroid, and testes.