As the end-stage of prostate cancer, metastatic castration-resistant prostate cancer(mCRPC) complicates the disease and therefore challenges the doctors. In October 2018, an 87-year-old patient diagnosed with metastatic prostate cancer was admitted to Shanghai General Hospital for evaluation and treatment. Poor basic health condition plus severe side effect resulted in patient’s poor compliance with treatment and irregular follow-up. The patient progressed to mCRPC in September 2020, and was given enzalutamide as first-line therapy, after which the patient’s PSA level was under control with no side effect.

Objective:To retrospectively analyze the clinical effects and complications of alcohol inactivation, irradiation inactivation, and liquid nitrogen inactivation in the treatment of femur osteosarcoma in children, in an attempt to provide a theoretical basis for clinical selection of in vitro inactivation methods of tumor bone segment. Methods:The clinical data of 93 children with femur osteosarcoma admitted to the Department of Bone and Soft Tissue, the Affi-liate Cancer Hospital of Zhengzhou University from January 2008 to December 2017 were retrospectively analyzed, and 40 children, including 21 males and 19 females, aged 8-18 (13.65±2.87) years, who were treated with in vitro inactivation and replantation of autogenous tumor bone segment, were screened.Among these children, there was alcohol inactivation in 15 cases, irradiation inactivation in 12 cases, and liquid nitrogen inactivation in 13 cases.A comparison was drawn on these 3 inactivation methods with respect to bone healing time, bone healing rate, tumor recurrence rate, infection rate, fracture or fixation failure rate, and revision rate. Results:All those 40 children were subject to valid medical followed-up, with the alcohol inactivation group for (102.60±16.55) months, the irradiation inactivation group for (59.33±6.39) months, and the liquid nitrogen inactivation for (36.85±6.49) months.The difference in follow-up time of 3 groups was statistically significant ( P<0.05). Compared with other 2 groups, the index of bone healing time, bone healing rate, infection rate and revision rate in the alcohol inactivation group were unfavorable, which showed a significant difference (all P<0.05); However, there was no significant difference in the recurrence rate, fracture rate or fixation failure rate compared with other 2 groups (all P>0.05); There was no significant difference in all above indexes between the irradiation group and the liquid nitrogen group (all P>0.05). Conclusions:Three in vitro inactivation methods for the treatment of tumor bone segment are safe and reliable.The alcohol inactivated bone has a long healing time and more complications.Both irradiation inactivation and liquid nitrogen inactivation are clinical options, but irradiation inactivation requires professional equipment, which may limit the clinical application.