National Cancer Institute National Cancer Institute
U.S. National Institutes of Health National Cancer Institute
Dictionary of Cancer Terms
Send to Printer
stage I melanoma

 Stage I is divided into stages IA and IB. In stage IA, the tumor is not more than 1 millimeter thick, with no ulceration. The tumor is in the epidermis (outer layer of skin) and upper layer of the dermis (inner layer of skin). In stage IB, the tumor is either not more than 1 millimeter thick and it has ulceration or it has spread into the dermis or the tissue below the skin; or more than 1 but not more than 2 millimeters thick, with no ulceration.

Enlarge
Two-panel drawing of stage I melanoma. The first panel shows a stage IA tumor that is not more than 1 millimeter thick, with no ulceration (break in the skin). The second panel shows two stage IB tumors. One tumor is not more than 1 millimeter thick, with ulceration, and the other tumor is more than 1 but not more than 2 millimeters thick, with no ulceration. Also shown are the epidermis (outer layer of the skin), the dermis (inner layer of the skin), and the subcutaneous tissue below the dermis.

Previous Definitions:stage I hypopharyngeal cancer, stage I kidney cancer, stage I laryngeal cancer, stage I lip and oral cavity cancer, stage I malignant mesothelioma
Next Definitions:stage I Merkel cell carcinoma, stage I multiple myeloma, stage I mycosis fungoides and the Sézary syndrome, stage I nasopharyngeal cancer, stage I non-small cell lung cancer