Phenol (phenol), also known as phenolic acid, carbolic acid, hydroxybenzene, is the simplest phenolic organic substance, a weak acid. It is a colorless crystal at room temperature and is toxic. Research shows that the concentration of 0.1-1% can inhibit the growth of bacteria, the concentration of 1-3% can kill bacteria, the concentration of 3-5% play a non-selective cytotoxic effect, the concentration of more than 5% can play a local anesthetic effect. The mechanism of action of phenol in treating tumor remnants is that it causes cellular protein degeneration and necrosis, resulting in increased cell permeability and cell structure destruction. The concentration of phenol used for local inactivation of bone tumors varies from 5 to 95%. Studies have shown that the use of 5% phenol can achieve similar therapeutic effects as high concentrations of phenol and has a good safety profile, therefore, 5% phenol is the more commonly used concentration. Increasing the temperature does not significantly increase the therapeutic effect, therefore, it is not recommended to increase the temperature of the phenol solution for tumor residual cavity inactivation to avoid increasing the absorption of phenol and resulting in toxicity. Methods of application include direct infusion into the tumor cavity at room temperature or application of tampons or gauze to the cavity. The residual cavity should be rinsed to remove tissue debris and blood clots prior to treatment with phenol to avoid compromising the treatment effect. Intraoperative care should be taken to protect the surrounding soft tissues. To achieve the desired treatment effect, the application of phenol should be applied at least 3 times. The duration of phenol application has been reported differently in the literature, ranging from 1 minute to 6 minutes. Some studies have shown that 6 minutes is required for the use of phenol to effectively kill giant cell tumor cells in bone. Thorough washing with saline is required after inactivation to avoid prolonged use leading to massive absorption of phenol resulting in cardiac or hepatic and renal failure. Phenol treatment of bone tumors was first reported in 1910, and Bloodgood first used Esmarch’s bandage to apply pressure to the limb to stop bleeding, then removed the lesion and inactivated pure carbolic acid for a variety of bone tumors, including giant cell tumors. A more satisfactory surgical result was achieved. The recurrence rate of tumor recurrence after scraping of giant cell tumor and treatment of residual cavity with phenol was 0-34%. Some studies have shown that the use of phenol treatment combined with bone cement filling of postoperative tumors can further reduce the recurrence rate.Capanna 1985 reported that in 69 cases of giant cell tumor lesions scraped and treated with bone grafting, 14 patients were inactivated with carbolic acid and 1 patient had local recurrence (7%). Capanna further reported in 1990 on the local treatment of giant cell tumor of bone, in which 45% of the patients who underwent tumor scraping without adjuvant inactivation had local recurrence in 280 patients, while phenol inactivation by lesion scraping (n=147 patients), liquid nitrogen freezing (n=20 patients), and liquid nitrogen freezing (n=20) and bone cement filling (n=187 patients), the number of patients who developed local recurrence was 17%. There was no significant difference in the recurrence rate between the groups with different treatment measures. The recurrence rate of giant cell tumor of bone could be significantly reduced to 3% in 33 patients using phenol inactivation combined with bone cement filling. In 2008, Knochentumoren1 reported 384 cases of giant cell tumor of the limb with a mean follow-up of 64.2 months. 306 cases underwent intracapsular curettage. Of these, local recurrence occurred in 49% of 103 patients who underwent lesion scraping alone, 33.3% of 102 patients who underwent scraping with bone cement filling, and 24.2% of patients who underwent lesion scraping, 85% phenol inactivation, and bone cement filling. There was no statistically significant difference between the two groups in which phenol inactivation was performed or not, while there was a statistically significant difference between the two groups in which bone cement filling was performed or not. Some authors in China have also used phenol to treat the residual cavity of giant cell tumor of bone. Huizhengguang et al. and Yi Jun et al. reported the use of phenol for inactivation of giant cell tumor of bone after scraping in 21 and 19 patients, respectively, and the postoperative recurrence rates were 9.5% and 11.7%, respectively. Gao Bo et al. 2010 reported 87 patients with giant cell tumor of bone who underwent lesion scraping with a mean follow-up of 70.2 months. Among them, phenol inactivation, anhydrous alcohol inactivation, and 50 zinc chloride inactivation were performed in 22, 46, and 19 cases, respectively, and the postoperative recurrence was 6, 14, and 3 cases, respectively, with recurrence rates of 27%, 30%, and 16%. There was no significant difference between the three groups after statistical analysis. The postoperative complications of local treatment of residual cavity with phenol are relatively rare, mainly chemical burns of the surrounding soft tissues, so care should be taken to protect the surrounding vascular nerve bundles and soft tissues when using phenol during surgery. The literature suggests that the use of phenol for residual cavity treatment is significantly less likely to result in complications such as osteoarthritis, infection, and fracture than liquid nitrogen cryotherapy, and no serious postoperative cardiopulmonary or hepatic or renal complications have been reported in the literature search. The most significant problem with the use of phenol as an adjunct to residual cavity treatment is contamination and its potential carcinogenicity.