Growth Rate of Experimental Tumor After the Use of Laser Energy

The growth rate of S91 melanoma in CDF1 mice has been compared in two groups. All tumors were injected into the subcutaneous tissue of the dorsal flank. When the tumors had reached 8 mm in diameter, the tumors in half of the animals were exposed to a single pulse of neodymium laser energy calculated so as to produce permanent tumor destruction in approximately one half of the animals exposed to laser. The mice developing recurrent tumors post laser, as well as all of the untreated animals, had their tumors measured daily until death. The rate of growth of the recurrent tumor was like that of the untreated control tumor in the linearly increasing portion of the growth curve. The recognition and measurement of the recurrent tumor recurring post laser in the early phase of its growth were unreliable because of the presence of an eschar on the skin after laser exposure.