GROWTH AFTER RUBBING BY TUMOR CUT SURFACE: COMPARATIVE STUDY BETWEEN THREADWIRE SAW-CUT AND BLUNTLY-CUT TUMORS

Abstract

Spondylectomy for extripation of spinal tumors would be performed through piecemeal excision or by total en bloc spondylectomy with cutting at the neural arch by the threadwire saw (T-saw) that is sometimes inevitably intralesional. The purpose of this study was to compare the potential for tumor growth after rubbing of the cut surface of tumors cut by either T-saw or blunt instrument against the subcutaneous tissues of nude mice. Tumors were prepared by subcutaneous injection of human HT 1080 fibrosarcoma cells in nude mice. The animals were sacrificed, and tumors were harvested en bloc and cut with either a T-saw or artery forceps. A 3-cm wound was created on the backs of other (plain) nude mice. The tumor's cut surface was rubbed for 10 seconds against the subcutaneous tissue of one of these nude mice. The wounds were then sutured. Tumor blocks were inoculated into other nude mice. Nude mice were followed for occurrence of tumor growth. Tumor growth occurred in all nude mice after block inoculation. The incidence of tumor growth after rubbing with the tumor surfaces cut with T-saw and artery forceps were 16.7% and 58.3% respectively (P = 0.035). Onset of tumor growth after tumor rubbing and inoculation of tumor blocks were 30.1 ± 25 and 12.2 ± 5 days respectively (P = 0.015). Rubbing of T-saw-cut tumor surface has less possibility of causing tumor growth than rubbing of surface of bluntly-cut tumors.