Roentgen Therapy of Hypertrophic Scars and Keloids

Abstract

Keloids are benign, often unencapsulated, overgrowths of connective tissue which may be caused by traumatic, infectious, chemical, or physical agents. Clinical differentiation between keloid and hypertrophic scar is not always sharply defined, yet true keloid tends to progress and almost never regresses with time, while hypertrophic scar tends to regress. Both are of clinical importance because of the symptoms they may cause, because of their unsightliness, or finally because they may interfere with normal function. The mechanism of keloid and hypertrophic scar formation has to do with a disturbance in the normal control of growth of connective tissue. The exact cause of this disturbance is still unknown. The degree of proliferation varies greatly in different individuals, and at different times in the same individual. Literature Keloids are stated by Hazen (1) to have been first treated with roentgen rays by Albers-Schoenberg and Pusey. Wickham and Degrais, according to Daland (2), were the first to use radium in the treatment of keloid. Heidingsfeld (3) in 1909 pointed out that differentiation between true and false keloid is not possible on clinical or histological grounds, that the differentiation of keloid in general from scar is not possible on histological grounds, but that keloid and scar can be differentiated histologically from normal collagenous connective tissue. Pusey in discussion substantiates these points and states that there is no essential difference between hypertrophic scar and keloid. Herzog (4) discusses the histogenesis of connective-tissue elements and their relationship to wound healing and speaks of the innate capacity of histiocytes to become fibroblasts. He cites anatomical investigations in stating that collagen and elastic or yellow fibers are probably both derived from the protoplasmic substance of fibroblasts and connective-tissue cells. Hodges (6) notes that, in spontaneous keloid regression, dilated capillaries and skin wrinkling have been observed, so that these changes are not necessarily due to roentgen rays. Bohrod (7) in the discussion of keloids and sexual selection quotes different authors as having found a negro to white ratio of from 14 to 1 to 9 to 1. This author also mentions that keloids have been produced by scarification in the puberty rites of certain primitive peoples and those who developed the largest keloids mated the earliest; thus keloid became the symbol of great fertility and the tendency perpetuated itself. Brenizer (8) advances the hypothesis that negroes may be more often lacking in a growth-restraining substance than white persons. Geschickter (9) finds a disturbed bio-assay of gonadotropic substance and estrin in keloid patients while he, as well as del Giudice (10), quote others who feel that altered calcium metabolism may be a factor in keloid formation.