Superficial spreading melanoma (clinical appearance)
Relationship between survival and melanoma thickness
Reference
Stadelman WK, Rapaport DP, Soong S-J et. al. Prognostic clinical and
pathological features. In Cutaneous Melanoma, CM Balch, AN Houghton, AJ
Sober, A-J Soong Editors. 3rd Ed. Quality Medical Publishing, Inc, St.
Louis, Missouri, 1998: pagg. 12-20.
Relationship between survival and Clark's levels
PROGNOSTIC FACTORS IN CUTANEOUS MELANOMA
In stage I and II melanoma (localized melanoma without clinical evidence of nodal metastasis), the main clinical and histological prognostic factors are:
SEX. The incidence of melanoma is fairly equally divided between men (48%) and women (52%). However, women show an overall survival rate higher than men. ANATOMIC LOCATION. Subjects with melanoma affecting extremities have a higher survival rate than patients with melanoma affecting the trunk, the head and the neck. There are no differences in sirvival between patients with upper or lower extremity tumors, and there is no difference in survival between those with head and neck or trunk melanomas. Tumors located over the hands and feet had uniformly worse prognosis; this, however, is not confirmed by all studies. AGE. Older patients tend to have a worse prognosis. PREGNANCY.Pregnancy at the time of diagnosis or a subsequent pregnancy after the diagnosis of melanoma has not negative influence on future survival. TUMOR THICKNESS (BRESLOW'S INDEX). It is the measurement, expressed in mm, of the melanoma invasion. It is calculated on the section which contains the thickest part of the tumor, measuring vertically from the granular layer (excluding the horny layer which may have variable thickness in the varies sites) to the deepest melanoma cell. If the tumor is ulcerated, it is measured from the ulcer base uo to the deepest point. Detached melanoma nodules (microsatellites) immediately deep to the main tumor mass are now included in the measurement. Measurements close to hair follicles are to be avoided, because may give a false value. ULCERATION. The presence of ulceration carries a worse prognosis. (CLARK'S) LEVEL. It is an assessment of depth of invasion of melanoma related to anatomical structures of the skin. There are 5 levels: level I, melanoma limited by the basal membrane (epidermis, follicular and adnexal epithelia), in situ; level II, discontinuous invasion or the papillary dermis; levell III, massive invasion of the papillary dermis; level IV, invasion of the reticular dermis; level V, invasion of the subcutaneous fat. Papillary dermis is distinguished by reticular dermis because is looser and composed of vertical oriented thinner collagen. Reticular dermis is less loose, is composed of horizontal and thicker collagen fascicles and contains eccrine coils. SENTINEL LYMPH NODE STATUS. The presence of occult micrometastases in the sentinel lymph node (see page 6) is a factor which carries a worse prognosis (stage III melanoma). The overall 10-year survival rate is 65% with negative sentinel lymph node and 45% with positive sentinel lymph node. HISTOLOGIC TYPE (see
page 1). Traditionally, nodular melanoma was considered to be associated with a prognosis worse than superficial spreading melanoma; however, when the thickness of the melanoma is accounted for, superficial spreading melanoma and nodular melanoma have the same 10-year survival rate. A slightly better prognosis is attributed to lentigo maligna melanoma and a slightly worse one to acral lentiginous melanoma. LYMPHOCYTE INFILTRATION. it has no prognostic significance, even if some author has found different results. REGRESSION. The presence of histologic regression does not influence significantly the prognosis.
page 9
The other pages
page 13: Merkel cell carcinoma
page 14: Basal cell carcinoma
page 15: Melanoma in paediatric age