Patient selection: malignant melanoma
Parameter: The thickness is measured at the thickest part of the lesion from the top of the granular cell layer to the deepest point of penetration, utilizing an optical micrometer.
probability of survival at 10 years =
= 0.966 * (EXP(-0.2016 * (thickness in mm)))
probability of death at 10 years =
= 1 - (probability of survival at 10 years)
Limitation - Tumor thickness measurements may be inaccurate for a variety of factors, including:
(1) ulceration of the lesion
(2) tissue shrinkage on fixation
(3) tangential sectioning of the specimen
(4) variation in epidermal thickness depending on anatomic site
(5) inadequate sampling of the thickest part of the lesion.