Endoprosthetics of the hip joint allows provide early activation of the patient, in the first days after the surgery, to begin functional and psychosocial rehabilitation in the hospital, achieve good cosmetic and functional results, and continue conservative treatment, on time.

The study included 172 patients with primary bone sarcomas, metastatic lesions, benign bone tumors, who from March 1996 to December 2018 performed 194 primary and revision operations. In the study group of patients, 47.1% were diagnosed with a primary malignant tumor, 37.8% had metastatic lesion. The mean follow-up period was 80.87 months. The leading complication at the time of the endoprosthetics was late aseptic instability (Type IIB — 37.5%).

Primary and revision endoprosthetics survival after 5 years was 91.9%, after 10 years was 81.3%, after 15 years was 76.5%, after 20 years was 68% of patients. The average functional result on the MSTS scale after 6 months after primary and revision endoprosthetics was 72.6%, after 12 months 84.2%. Aseptic instability is the leading complication in the postoperative period 6.2%.

The introduction of innovative technological solutions in the design, materials of the endoprosthesis, will become a means of ensuring a further progressive decrease in the frequency of complications and increase the life of the implant.

Introduction. Primary tumor excision is a simple, commonly used and relatively effective treatment for localized cutaneous melanoma (CM). However, in 19-24% of cases, regional lymph node recurrence occurs after excision due to the presence of micrometastases in lymph nodes at the moment of treatment of the primary tumor. Sentinel lymph node (SLN) biopsy is the only reliable method for identifying micrometastatic disease in the regional nodes. Despite the rapid acceptance of SLN biopsy into clinical practice, many controversies remain according to recent literature.

The purpose of this study was to assess short-term and long-term results of SLN biopsy in patients with clinically localized CM using a domestic radiopharmaceutical and equipment.

Materials and methods. This study enrolled 847 consecutive patients with clinically localized CM (any сТ, N0, M0) who were divided into three groups. Group I included 212 patients treated with wide excision alone for CM. Group II included 241 patients who received wide excision for CM followed by one-stage preventive lymphadenectomy. Group III included 394 patients who underwent wide excision for CM and SLN biopsy. SLN localization was performed with the domestic radiopharmaceutical ^99mTc-Technephyt. Intraoperative SLN mapping was undertaken using the domestic handheld gamma detection probe (RADICAL).

Results. In patients with CM <1 mm in thickness, the overall rate of regional lymph node metastasis was 5.9% in group I, 6.9% in group II and 4.7% in group III. The low incidence of regional lymph node metastasis did not require an urgent need for additional methods of regional control in these patients. The five- and seven-year recurrence-free survival rates were 82.4±5.7% and 82.4±5.7% in group I, 90.9±6.2% and 90.9±6.2% (p=0.080) in group II, and 90.8±5.2% and 90.8±5.2% in group III (p=0.106 and p=0.795, respectively). In patients with thin CM, the disease-specific actuarial survival rates were 87.3±5.4% and 87.3±5.4% in group I, there were no deaths during follow-up periods in group II (p=0.030), and 96.9±2.1% and 89.5±7.4 in group III (p=0.514 and p=0.151, respectively). In patients with CM >1 mm thick, the overall rate of regional lymph node metastasis was 24.4% in group I, 25.9% in group II and 29.1% in group III. In group I, regional recurrence occurred. In group II, preventive lymphadenectomy revealed lymph node micrometastasis in 11.3% of cases and regional recurrence in intact lymph nodes in 14.6% of cases, whereas in group III, SLN biopsy revealed lymph node micrometastasis in 23.9% of cases and regional recurrence in intact lymph nodes in 5.2% of cases (p=0.000). The regional recurrence rates were significantly lower in groups II and III than in group I treated with primary melanoma excision alone (p=0.047 and p=0.000, respectively). Remarkably, when lymph nodes were involved, the incidence rates of in-transit melanoma metastases remained stable and did not depend on time and technique for the detection of nodal metastases. So, in-transit metastases occurred in 21.1% of patients with lymph node recurrence in group I, in 20.8% of patients with lymph node micrometastasis in group II, and in 20.3% of patients with SLN micrometastasis in group III versus 3.4-5.1% of patients without lymph node involvement (p=0.000). The five- and seven-year recurrence-free survival rates in CM >1 mm thick were 51.9±4.4% and 48.8±4.5% in group I, 54.9±3.7% and 51.0±3.8% in group II (p=0.648) versus 71.0±3.3% and 64.4±4.8% in group III (p=0.009 and p=0.033, respectively). The disease-specific actuarial survival rates were 63.5±4.3% and 58.1±4.6% in group I, 69.4±3.5% and 63.4±3.8% in group II (p=0.405) versus 86.0±3.0% and 86.0±3.0% in group III (p=0.000 and p=0.000, respectively).

Conclusion. SLN biopsy for CM is minimally invasive and highly accurate in identifying occult nodal disease. It enables to improve short-term and long-term treatment outcomes in patients with CM >1 mm thick. The use of the domestic radiopharmaceutical and equipment makes SLN biopsy highly reproducible and more easily accessible.

Currently during complex treatment of malignant neoplasms of various localizations, perfusion technologies are used more commonly. We performed the literature data analysis of the possibilities of intraarterial drugs perfusion methods in treatment of various types of tumors. We provided data on treatment of liver tumors, cholangiocarcinoma, pancreatic tumors, breast cancer, tumors of the lung, pelvis, head and neck, central nervous system.

It is noted that the main principles of modern tumors perfusion chemotherapy are: targeted hypertonic, hypooncotic, ischemic superselective delivery of a chemotherapeutic drug without binding to plasma and erythrocytes; cumulation of drugs in the tumor tissue due to obstruction of venous outflow from the tumor, inhibition of the drug reabsorption; the possibility of relatively rapid repeated infusions of drugs to minimize the spatial reorganization of the tumor and mutations of its cells; protection of healthy tissue from the drug adverse effects. It is indicated that the technical aspects of the method and the choice of anticancer drugs depend on the individual anatomy of the organ and the specific biological characteristics of the tumor, the inclusion of which allows for endovascular isolation of the tumor tissue.

In more than 80% of cases of primary and metastatic bone tumors with a modern integrated approach to treatment, it is possible to perform organ-sparing intervention for resection with joint replacement. The frequency of revision interventions for various complications, according to various sources, is from 5 to 50%. The article provides an analysis of the results of arthroplasty and revision arthroplasty for primary and metastatic bone tumors in the A.F. Tsyba MRRC for the period from 2012 to 2018. Background. With advances in combined modality therapy for osseous malignancies, it has become possible to perform endoprosthetic joint replacement for limb salvage after bone resection in more than 80% of patients with primary and metastatic bone tumors. According to the literature data, the frequency of revision procedures for various complications is from 5% to 50%. This study presents an analysis of the results of endoprosthetic replacement and endoprosthetic revision for primary and metastatic bone tumors performed in MRRC between 2012 and 2018.

Purpose. To analyze the results of endoprosthetic replacement of large joints in cancer patients and to identify the causes of complications.

Materials and methods. In the years 2012—2018, we performed 248 endoprosthetic replacements for primary and metastatic tumors of the musculoskeletal system including 42 (17%) endoprosthesis revisions. A greater number of revision procedures were done for tumors of the distal femur and the proximal tibia (55% and 22%, respectively).

Results. Revisions were performed for aseptic instability of one of endoprosthesis stems in 19 (45.2%) cases, for infectious complications in 10 (23.8%), for breakage of the components of the endoprosthesis in 6 (14.3%), and for periprosthetic fractures in 2 (4.8%) cases. Endoprostheses were built up 5 times (11.9 %) due to recurrent disease.

Conclusion. Endoprosthesis revision is one of the most important challenges in orthopedic oncology indicating the need for an individualized approach. Revision procedures are extremely complex due to deficiency of intact bone tissue and surrounding soft tissue, as well as due to infected endoprosthesis bed most often requiring two-stage surgical interventions.

Mesenchymal chondrosarcoma is an extremely rare disease. A special kind of chondrosarcoma, quite sharply different in its clinical and x-ray morphological features from its other variants, and has definitely a different tactic of diagnosis and treatment.

Chondrosarcomas are the most aggressive malignant bone tumors that have a high risk of local recurrence and metastasis. The primary treatment modality of chondrosarcoma is surgical excision. We present a report of a rare clinical case of primary chondrosarcoma of the second metacarpal bone of the right hand in a 73-year-old patient who underwent surgical extirpation of the second metacarpal bone in which the tumor was removed. The bone defect was replaced using an individually tailored 3D-printed endoprosthesis.

Askin tumor or malignant small cell thoracopulmonary tumor is extremely rare, practically is isolated incident, it is characterized with extreme malignancy and unsatisfactory treatment results due to difficulties in diagnostics and late detection. This paper presents a clinical case of prolonged observation of a patient with Ewing's sarcoma of the second rib with metastasis in the right lung after nonradical treatment at the place of residence. Combination treatment with an emphasis on radiation therapy was carried out at the Medical Radiological Scientific Center. Patient was treated and maintained her high quality of life. The patient is being observed for 18 years, she graduated from the university, working.