Vol 18, No 1 (2026)

Introduction. Giant cell tumor of bone is characterized by high risk of local recurrence, especially during denosumab therapy complicating visual control of the radicalness of surgical intervention. Despite constant improvement of tumor excochleation technique, consensus on the optimal surgical technique has not yet been reached as the results of comparative studies are often contradictory.

Aim. To compare oncological outcomes and determine risk factors in patients with giant tumor of bone after standard and extended excochleations against the background of neoadjuvant therapy with denosumab.

Materials and methods. During single-center prospective-retrospective study, data of 83 patients with giant cell tumor of bone were analyzed. The extended excochleation group (n = 33) was formed according to compliance with a strict protocol (length of cortical window >70 % of tumor length, combination use of local adjuvants). The group included 23 patients recruited prospectively since 01.01.2024 and 10 patients included retrospectively from earlier period according to the same criteria. The group of standard excochleation (historic control group) (p = 50) included patients who underwent surgery between 01.01.2014 and 31.12.2023 without strict protocol per the surgeon’s decision. The primary endpoint was the rate of local recurrences.

Results. During the follow-up, local recurrence developed in 31 (62 %) patients of the control group and 4 (12.1 %) patients of the extended excochleation group (p < 0.001). The risk of recurrence for standard technique was 3.7-fold higher (hazard ratio 3.71; 95 % confidence interval 1.31–10.53; p = 0.014). ROC analysis showed that the ratio between cortical window and tumor length ≤69 % is a significant predictor of recurrence (area under curve (AUC) = 0.674; p = 0.012). The use of high-speed burr was statistically significantly associated with decreased risk of local recurrence (p = 0.019).

Conclusion. Implementation of standardized protocol of extended excochleation based on formation of a wide cortical window and combination administration of adjuvants into clinical practice significantly reduces the risk of local recurrence of giant cell tumor of bone in patients receiving denosumab. A quantitative criterion of “cortical window length >69 % of tumor length” can serve as an intraoperative landmark for reaching appropriate surgical radicalness.

The article presents the history of the development of prosthetic joints. After pioneering work using ivory and metal for prosthetics, reconstruction became a significant achievement and attempts to replace all major joints were documented. An expanded understanding of the processes and basic principles implemented in modern prostheses can become the basis for further improving their functional characteristics and service life, as well as for increasing the level of care provided and the degree of patient satisfaction.

For modern treatment schemes for bone sarcomas (BS), overall survival of children and adolescents is 60–70 %. This treatment can be accompanied by disruption of intraosseous metabolism which leads to decreased bone mineral density (BMD). Clinical equivalents of decreased BMD are osteoporosis/osteopenia which are reported in 45 % of patients cured of various malignant neoplasms. Children and adolescents with BS have higher incidence of osteoporosis (43–65 % of cases) compared to patients with other types of malignant tumors.

Aim. To determine the rate of BMD abnormalities and risk factors of osteoporosis in children and adolescents who completed BS therapy.

Results of scientific articles published in the eLIBRARY, PubMed, Scopus databases, as well as on the Research Gate, Google Scholar platforms were analyzed. In patients with BS, the following main etiologic and pathogenetic mechanisms of BMD decrease were identified: tumor process extent, mutilating surgical interventions, implantation of various implants, limitation of mobility, administration of cytostatic drugs, high-dose radiotherapy, genetic predisposition. BMD abnormalities and bone fractures develop even in unaffected by the tumor parts of the skeleton. Considering high risk of osteoporosis in patients with BS, it is important to start diagnostic process and correction of this complication as soon as possible after the start of antitumor therapy, as well as monitor BMD even in patients in long-term remission.

Introduction. Approximately 50 % of patients with neurofibromatosis type 1 (NF1) develop plexiform neurofibromas (PNs) which cause pain, functional abnormalities and disfigurement. In patients with NF1, vasculopathies and hemostasis disorders can occur, and surgical resection of PN can cause life-threatening hemorrhages. Standard treatment method of symptomatic PNs is surgical treatment but complete resection is often impossible. Additionally, renewal of PN growth is observed in 43 % of patients. Selumetinib, inhibitor of mitogen-activated protein kinase (MEK), allows to significantly control PNs in clinical trials and practice which confirms the possibility of its combination with surgical treatment.

Aim. To evaluate the results of surgical treatment of adult patients with symptomatic PNs, determine factors promoting development of complications and recurrences, and justify the use of selumetinib as a subsequent therapy.

Materials and methods. Retrospective analysis of treatment of adult patients with NF1 and symptomatic PNs who underwent symptomatic surgical treatment between July 2022 and September 2025. The study included 15 patients (11 women and 4 men); median PN volume was 1023 (14.56–74,800.00) mL. Some patients required multistage surgeries. Median follow-up was 10.5 months (95 % CI 3.75–23.00). PN sites: thoracic wall – 1 case, lower limb – 7, lumbar region – 3, back – 2, gluteal region – 2. In 3 cases, malignant tumor of the peripheral nerve sheath was reported; in 13 patients, mutation in the NF gene was identified.

Results. Surgical intervention relieved symptoms but led to significant complications. Median intraoperative blood loss volume was 700 (5–32,000 mL) mL. In 28 % of patients, complications associated with wound healing developed, in 5 (42 %) patients – clinical and/or radiological disease recurrence. Median disease-specific survival was 32 months (95 % CI 14–36). One patient died due to coagulopathy (blood loss volume was 32 L, operative time 9 h). Selumetinib in the postoperative period was prescribed to 3 (20 %) patients with residual or progressive disease. Significant differences were observed in PN volumes depending on sex (p = 0.009), as well as significant effect of PN volume on а operative time (p = 0.041), blood loss volume (p = 0.011), development of secondary wound healing (p = 0.016) and renewal of tumor growth (p = 0.028) was identified. There was no association between development of malignant tumor of the peripheral nerve and PN volume (p = 0.885).

Conclusion. Surgical treatment of PN is characterized by increased difficulty due to high rate of intraoperative complications, primarily blood loss, and leads only to temporary relief. The obtained dependencies (effect of PN volume on blood loss volume, operative time, development of secondary wound healing, and PN growth renewal) is statistically significantly confirms risks associated with high PN size. Correlation the volume of PN volume with female sex is also of interest. Notably, none of the patients receiving selumetinib after surgery had tumor growth, but follow-up is very short. A trend is observed towards selection of combination treatment where aggressive surgical techniques are accompanied by timely MEK prescription which prevents repeat PN growth and improves/preserves long-term clinical and radiological results.

The article presents a review of immune-related cutaneous adverse events associated with checkpoint inhibitors. Pathogenetic mechanisms of immune-related complications associated with T cell hyperactivation and disruption of peripheral tolerance are considered. Clinical and pathomorphological characteristics of the most common skin reactions are described: maculopapular rash, itch, lichenoid and psoriasiform rashes, bullous pemphigoid, as well as rare and life-threatening syndromes such as drug reaction with eosinophilia and systemic symptoms (DRESS syndrome), Stevens–Johnson syndrome, toxic epidermal necrolysis. Special attention is paid to the analysis of psoriasiform rashes and exacerbation of psoriasis vulgaris which are associated with significant diagnostic difficulties and require differential approach to treatment. To demonstrate the importance of early involvement of a dermatologist for diagnosis verification (including skin biopsy) and prescription of pathogenetically justified steroid-sparing therapy, clinical cases are presented.

Multidisciplinary approach and personalized management of patients with immune-related cutaneous adverse events allow to control skin toxicity, minimize the necessity of checkpoint inhibitor cancellation, and preserve efficacy of antitumor treatment.

Clear cell carcinoma of soft tissue is an ultrarare malignant tumor with melanocytic differentiations. It primarily affects distal parts of the limbs in young patients and is characterized by high metastatic potential and diagnostic complexity.

The article presents a clinical case of diagnosis and treatment of clear cell sarcoma of soft tissue of the foot in a 28-year-old male patient which demonstrates the importance of cancer alertness in evaluation of soft tissue neoplasms, necessity of histological examination of any neoplasms, and use of expanded immunohistochemical and molecular studies (PRAME, EWSR1::ATF1) for differential diagnosis of this pathology and melanoma.