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Dermatopathology: Practical & Conceptual July - September 2001
Evolution in Thinking: Criteria for Clinical Diagnosis of Melanoma, 1947–2000: A Critique in Historical Perspective
Mary Aldrene L. Tan, M.D.
A. Bernard Ackerman, M.D.
Becker and Obermayer
Ormsby and Montgomery
Sulzberger and Wolf
Pillsbury, Shelley, and Kligman
Fitzpatrick and Clark
Lewis and Wheeler
Callen, Stawiski, and Voorhees
Roses, Harris, and Ackerman
Dobson and Abele
Friedman, Rigel, and Kopf
Fitzpatrick, Rhodes, Sober, and Mihm
Koh and Rogers
McCarthy et al.
Mooi WJ and Krausy
Fitzpatrick, Milton, Balch, Shaw, McCarthy, and Sober
National Institutes of Health Consensus Conference
Holzle, Kind, Plewig, and Burgdorf
Marghoob, Slade, Kopf, Rigel, and Friedman
Arndt, Wintroub, Robinson, and LeBoit
Elder and Elenitsas
Maize et al.
Langley, Fitzpatrick, and Sober
Farmer and Hood
Fleischer, Feldman, Katz, and Clayton
Ackerman, Kerl, Sánchez, et al.
Elder and Elenitsas
"In their nontumorigenic stage, melanomas tend to expand more or less inexorably along the radii of an imperfect circle as viewed clinically. The clinically derived term "radial growth" has no intuitive histologic meaning, and the histologic term "horizontal growth phase" has been suggested as an alternative. The major clinical diagnostic criteria have been summarized as "
criteria," which include lesional
symmetry (one half of a lesion does not match the other half in shape or in color distribution), lesional
order irregularity (the lesion tends to have an indented coastline like the map of a small island), lesional
olor variegation (the surface is multicolored and may include shades of tan, brown, blue-black, gray-white, and other variations), and lesional
iameter (generally greater than 6 mm, although some melanomas are smaller) . . ."
"Clinically, the tumorigenic vertical growth phase is qualitatively different from the plaquelike radial growth phase. The tumor appears as an expanding papule within a previously indolent plaque lesion, and grows in three dimensions in a balloonlike fashion to form a nodule. Typically, the
criteria do not apply to the tumor nodule itself, which is commonly symmetrical with smooth borders. The color is often quite uniform, and may be pink rather than blue-black, and the diameter is often less than 6 mm, even in a quite high-risk lesion . . ."
Elder D, Elenitsas R. Benign Pigmented Lesions and Malignant Melanoma. In: Elder D, Elenitsas R, Jaworsky C, Johnson B Jr, eds.
Lever's Histopathology of the Skin.
8th Edition. Philadelphia: Lippincott-Raven Publishers, 1997:656.
Attempting to contrast "radial growth phase" and "vertical growth phase" is as futile as trying to comprehend the sense of "no intuitive histologic meaning." In short, vertical is a component of radial and, therefore, vertical and radial cannot be contrasted. Moreover, through a microscope, no histopathologist is able to discern when the so-called radial growth phase ends and the vertical growth phase begins; any definitive judgment about that is mere confabulation.
The ABCDs that began as a mnemonic to aid physicians in recognizing lesions of melanoma clinically and soon became a tool for teaching the laity how to become proficient at that, by 1997 had become the major teaching device for instructing physicians about how to identify melanomas clinically. Elder and Elenitsas, in the preceding passage, attempt to explain the clinical features of the ABCDs by way of Clark's notion of a "plaque-like radial growth phase" and a "tumorogenic vertical growth phase." Apart from inability to correlate the two because of the inherently flawed concept of "radial" versus "vertical" growth phase, the co-authors acknowledge frankly the limitations of the ABCDs as follows: "Typically, the ABCD criteria do not apply to the tumor nodule itself, which is commonly symmetrical with smooth borders. The color is often quite uniform, and may be pink rather than blue-black, and the diameter is often less than 6 mm, even in a quite high-risk lesion . . ." In those two sentences, Elder and Elenitsas effectively demolish the validity of the ABCDs.
Last, by focusing on the "tumorogenic vertical growth phase," Elder and Elenitsas, seemingly unwittingly, emphasize in the evolution of melanoma a stage that usually is incurable, the neoplastic melanocytes having already metastasized by the time a nodule or a tumor has formed. That is precisely why stress must be placed on recognizing melanoma when the lesion is flat and curable by simple excision.
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