THE VIABILITY OF CELLS IN THE WASTE PRODUCTS OF CO2-LASER EVAPORATION OF CLOUDMAN MOUSE MELANOMAS

The viability of cells present in waste products originating during C02-laser evaporation of Cloudman S91 mouse melanomas was investigated. Cytologic smears showed mainly carbonized particles and thermally damaged cells but some morphologically intact cells as well. Viability was tested with the trypan blue test, by in vitro culture and intramuscular and intraperitoneal inoculations in syngeneic mice. No dye-excluding cells were found in the trypan blue test. Growth was noted neither in vitro nor in vivo in the 127 mice, intramuscularly or intraperitoneally injected with 1OS-5 X 10s/10 pl smoke or debris particles, and killed four weeks after inoculation. Viable tumor cells, derived from a Cloudman melanoma cell line and added to the smoke and debris suspensions, remained viable. Thus, a toxic influence of smoke and debris particles in viable tumor cells, which would make the viability tests meaningless, was excluded. It is highly unlikely that viable tumor cells do occur in the waste products of C02-laser tumor vaporization. Cancer 49:61-67. 1982. HE SURGICAL C02-laser is an interesting tool that T is being introduced in several areas of clinical tumor surgery.'-' Applications in ear, nose, and throat and in gyne~ology'~-~~ appear to be fruitful. One of the interesting aspects to the tumor surgeon is the possibility of no-touch removal of tissue by evapoDuring evaporation of tissue a cloud of volatilized material (smoke) and coarse carbonized tissue particles (debris) are produced. It is very important to know whether still-viable tumor cells are present in this waste material since airborne viable tumor cells may give rise to recurring tumor. This point deserves special attention since the surgical pulsed neodymium laser was shown to cause spread of airborne viable tumor.27