Objective:To demonstrate the feasibility of the osteosarcoma devitalization method by vacuum dehydration at room tem-perature. Methods:For the in vivo study, the VX2 tumor mass was treated by vacuum dehydration, rehydrated in ice water, and im-planted in the rabbit to determine the safety time to deactivate the tumor. For the in vitro study, the osteosarcoma mass was devital-ized by vacuum dehydration, and the dehydration rate and ATPase activity were determined. Histopathological changes in the tumor were also observed. The change in the biomechanical strength of rabbit bone and tendon after vacuum devitalization treatment was detected. Results:At room temperature, the safety time to deactivate the VX2 tumor was 60 min, and the dehydration rate was 93.8%at this time point. After vacuum dehydration, the tumor mass evidently shrunk, presenting a porous structure. The osteosarcoma cell became small, and cell structure damage was observed under light microscope. Disrupted cell membrane and organelles were seen un-der transmission electron microscope as well as broken down chromosomes. The activity of ATPase was evidently lower than in the control group. The strength of bone and tendon did not decrease significantly after vacuum dehydration. Conclusion:Treatment by vacuum dehydration at room temperature for 60 min does not result in differences of the bone and tendon strength. However, it can inactivate both soft tissue and bone tumor mass completely.

Objective To discuss the safety and effectiveness of transurethral resection of the prostate (TURP) on large-size (≥ 80 ml) benign prostatic hyperplasia (BPH).Methods Retrospective analysis of 958 BPH patients in Southwest Hospital during January 2010 to January 2013 was conducted.The patients were grouped into ≥80 ml prostate group (Group A) and ＜80 ml prostate group (Group B) according to the volume of prostate.Comparison was made between the 2 groups on the safety and effectiveness of TURP.Results There were 276 patients in Group A and 682 in Group B.No significant differences were shown in average age and preoperative American society of anesthesiology score of Group A and B.Compared with Group B,decrement in hemoglobin level and blood Na+ concentration of Group A was more significant (P＜0.01).There were more prostate tissues excised and duration of the operations was longer (P＜0.01).No significant difference was observed in peri-operative complications graded by the modified Clavien classification system,catheter durations and durations of hospital stay between the 2 groups (P＞0.05).At 6 months after the surgery,average maximum urinary flow rate (Qmax) increased from 5.9±2.9 ml/s to 17.1±8.2 ml/s for Group A and 6.1±3.0 ml/s to 17.5±6.4 ml/s for Group B,both groups showed significant increase in Qmax after surgery(P＜0.01).Six months after surgery,international prostate symptom score (IPSS) of Group A decreased from 23.7±6.1 to 5.9±4.9 while IPSS of Group B decreased from 23.1±5.5 to 6.2±4.4,both groups showed a significant decrease (P＜0.01).No significant difference was shown in IPSS,quality of life,Qmax,postvoid residual urine volume and occurrence rate of long-term complications after 6 months between the 2 groups (P＞0.05).Conclusion TURP is as safe and effective in treating large-size BPH as treating medium and small-size BPH.

Objective: To summarize the experience in the treatment of infection after limb salvage surgery for malignant tumor around knee joint, and explore the risk factor related to infection after limb salvage surgery. Methods: A clinical data of 212 patients with malignant tumor around the knee joint underwent limb salvage surgery between January 2008 and December 2017 were retrospectively analyzed. Among them, 14 cases had infection after limb salvage surgery. Two cases of acute infection were treated with sensitive antibiotics; 12 cases of chronic infection were treated with debridement and antibiotic bone cement occupying device implantation in the first stage, and prosthesis revision (8 cases), knee joint fusion (2 cases), or amputation (2 cases) in the second stage after infection control. The age, gender, preoperative chemotherapy cycle, bone marrow suppression, serum albumin, hemoglobin, operation time, postoperative drainage time, and blood transfusion volume were analyzed to screen the risk factors related to infection after limb salvage surgery. The infection and tumor recurrence were observed, and the limb function was evaluated by Enneking scoring system. Results: The univariate analysis showed that the preoperative chemotherapy cycle, bone marrow suppression, operation time, and postoperative drainage time were the influencing factors of postoperative infection ( P<0.05). Multivariate analysis showed that the operation time, preoperative chemotherapy cycle, and postoperative drainage time were risk factors of postoperative infection ( P<0.05). Among the 14 patients, 1 patient died of traffic accident at 6 months after the second stage operation, and 13 patients were followed up 12.2-48.0 months (mean, 19.9 months). Two cases of acute infection cured. Among the 11 patients with chronic infection, 2 cases of subluxation of the antibiotic bone cement occupying device after the first stage operation occurred; 9 cases of infection cured and 2 cases recurred. At 12 months after operation, except 1 case died by accident, the Enneking scores of the other 13 patients were 12-26, with an average of 20. At last follow-up, 1 case of lung metastasis was still alive, and no tumor metastasis or recurrence was found in the rest. Conclusion: The time of limb salvage surgery, preoperative chemotherapy cycle, and drainage time after limb salvage surgery are the risk factors of infection after limb salvage surgery. Early etiological examination and drug sensitivity test is the key to the treatment of infection. One-stage debridement combined with antibiotic bone cement occupying device can effectively cure infection and save patients' limbs.

Objective To investigate the association between the osteogenic differentiation in the soft tissue lump and the clinicopathological characteristics of osteosarcoma patients. Methods We retrospectively reviewed the clinical data of conventional osteosarcoma patients with soft tissue lumps, including Enneking stages, chemotherapy sensitivity, overall survival and post-metastatic survival time. The ossification level in soft tissue lumps was assessed by imaging and the proportion of osteoid matrix was assessed by pathological examination. Results A total of 189 cases were included in this study. In patients with Enneking IIIB, non-osteoblastic, partially osteoblastic and osteoblastic types accounted for 30.2%, 9.6% and 6.3%, respectively. Non-osteoblastic osteosarcoma patients had a higher rate of initial metastasis (P < 0.05); Chemotherapy efficiency of non-osteoblastic, partially osteoblastic and osteoblastic types were 60.5%, 59.6% and 31.3%, respectively. The osteoblastic osteosarcoma held the worst rate of chemotherapy sensitivity (P < 0.05). The overall survival of non-osteoblastic osteosarcoma was shorter than those of partially osteoblastic and osteoblastic types (P < 0.05). Post-metastatic survival time of osteoblastic osteosarcoma was longer than that of non-osteoblastic osteosarcoma (P=0.078). Conclusion For conventional osteosarcoma, the osteogenesis level in soft tissue lumps is related to the surgical stage, chemotherapy sensitivity and prognosis of tumors, which may provide guidance for the individual decision regarding chemotherapy and surgery timing on patients.