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stage I melanoma

(... MEH-luh-NOH-muh)
Stage I is divided into stages IA and IB. In stage IA, the tumor is not more than 1 millimeter thick, with or without ulceration (a break in the skin). In stage IB, the tumor is more than 1 but not more than 2 millimeters thick, without ulceration.
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Two-panel drawing of stage I melanoma; the panel on the left shows a stage IA tumor that is not more than 1 millimeter thick, with ulceration (a break in the skin) and without ulceration. The panel on the right shows a stage IB tumor that is more than 1 but not more than 2 millimeters thick, without 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.Enlarge this image in new window
Stage I melanoma. In stage IA, the tumor is not more than 1 millimeter thick, with or without ulceration (a break in the skin). In stage IB, the tumor is more than 1 but not more than 2 millimeters thick, without ulceration. Skin thickness is different on different parts of the body.
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