OBJECTIVETo study the local infiltration length of spinal bone giant cell tumor and chordoma in various para-tumorous tissues.

METHODSSurgical specimens from 7 patients with bone giant cell tumor and 10 patients with chordoma were divided into 6 groups: cortical bone group (CBG, para-tumorous tissue is bone cortex with periosteum), cartilage group (CG, para-tumorous tissues contain intervertebral disc, cartilage endplate and facet joint cartilage), trabecular bone group (TBG), paraspinal muscle tissue group (MTG), adipose tissue group (ATG) and scar tissue group (STG). Macroscopically margin (MSM) in the fresh specimens, histological margin (HLM) in the H&E sections and molecular margin (MCM) in the immunohistochemical staining sections were measured respectively. Three types of the margins of each group and MSM-HLMs, and MSM-MCMs among all groups were compared.

RESULTSAnalysis of Variance comparing MSM, HLM and MCM within each group showed that there were significant differences in all groups (P < 0.05) except for CBG and CG. MSMs were significantly longer than HLMs and MCMs in TBG and MTG (P < 0.05), and MSMs were significantly longer than MCMs in ATG and STG (P < 0.05). MSM-HLMs and MSM-MCMs of TBG and ATG were significantly larger than those of CG and CBG. MSM-HLMs and MSM-MCMs of MTG and STG were significantly larger than those of CG; in addition, MSM-MCM of STG was significantly larger than CBG's. The maximum of tumor infiltration length in CBG, MTG, ATG and STG were 11.68 mm, 13.08 mm, 8.64 mm and 9.98 mm respectively.

CONCLUSIONSEach vertebra can be seen as a compartment, so total spondylectomy is an optimal procedure when bone giant cell tumor and chordoma localized in the compartment. To achieve a wide resection, a 1.3 cm wide margin in para-tumorous cancellous bone, a 1.5 cm wide margin in para-tumorous muscle and 1.0 cm wide margin in adipose tissues are necessary. First-time resection should be more aggressive and avoid tumor cell contamination. The surgical extent of salvage revision should contain para-tumorous scar tissue with the margin no less than 1.0 cm.