Vol 26, No 2 (2024)

Background. In oncology, of particular interest is the study of the T-cell receptor excision circles (TREC) and the κ-deletion B-cell receptor excision circles (KREC), which are extrachromosomal DNA structures. In many malignancies, the effectiveness of immune checkpoint inhibitors depends on the mutational load of the tumor, which correlates with the formation of specific antitumor immunity. Quantitative indicators of recombination excision circles reflect the occurrence of a different repertoire of T-cell receptors, an integral component in the formation of specific immunity. Understanding the change in quantitative values of TREC and KREC in cancer patients can improve the selection of patients for immunotherapy.

Aim. To determine quantitative indicators of TREC and KREC for immunological evaluation of patients with malignancies.

Materials and methods. The study included 55 healthy individuals and 180 patients with malignancies. Among healthy individuals, 49.1% (27/55) were males and 50.9% (28/55) females. Among patients with malignancies, 20.5% (37/180) were males and 79.5% (143/180) females. The median age in healthy individuals was 36 years [Q1–Q3: 26–58]. The median age in the group of patients with malignancies was 57 years [Q1–Q3: 47.5–67].

Results. In the general population of healthy individuals, the median TREC level was 60.1 [Q1-Q3: 31.3-188.9] and the median KREC level was 256 [Q1-Q3: 149.8-353]. In the general population of patients with malignancies, the median TREC rate was 4.6 [Q1-Q3: 0.9-17.3] and the median KREC was 111.9 [Q1-Q3: 29.3-339.28]. According to the results of the study, we noted statistically significant differences in TREC and KREC indices between all patients with malignancies and healthy individuals (p<0.001, p=0.001). Analysis of TREC and KREC indices in patients with malignancies of various localizations (breast cancer, ovarian cancer, lung cancer, colorectal cancer, skin melanoma, lymphomas) in comparison with healthy individuals statistically significant differences in TREC level were noted (p=0.001, p<0.001). When analyzing the KREC level in the studied groups, statistically significant differences in patients with ovarian malignancies (p<0.001), lymphoma (p<0.001), colorectal cancer (p=0.001) and melanoma (p=0.039) in comparison with healthy individuals were obtained. When comparing groups pairwise, it was found that TREC level in patients with malignancies in the age group of 25–44 years was significantly higher than in the age group of 45–60 years (p=0.03); TREC level in the age group of 25–44 years was significantly higher than in the age group of persons over 60 years (p<0.001); TREC level in the age group of 45–60 years was significantly higher than in the age group over 60 years (p<0.001). Statistically significant differences of KREC level in the studied patients with malignancies depending on the age group were not established (p=0.16), there were no age differences of groups by KREC level.

Conclusion. The results demonstrate a significant decrease in TREC and KREC levels in patients with malignancies compared to healthy individuals. The study of TREC and KREC excision circles in peripheral blood is one of the promising approaches for the immunological evaluation of cancer patients.

Background. The COVID-19 pandemic, which swept the world in 2020–2021, had a significant impact on the epidemiological picture of hematological malignancies.

Aim. To study the dynamics of epidemiological indicators of five chronic hemoblastoses in Moscow over a 12-year period, and also to assess the impact of the COVID-19 pandemic on these indicators.

Materials and methods. A population-based study was conducted for five types of oncohematological diseases: multiple myeloma, Hodgkin's lymphoma, follicular lymphoma, chronic lymphocytic leukemia, chronic myeloid leukemia. The annual rates of morbidity, mortality, prevalence of these nosologies, overall survival, and expected overall survival were calculated. Gender and age characteristics for each disease were determined.

Results and discussion. The present study showed a uniform increase in the incidence and prevalence of five hematological malignancies between 2012 and 2019. Convincing evidence of an increase in mortality and a decrease in the number of diagnosed cases in comparison with the expected figures for these hematological malignancies in 2020–2021 was presented. A greater reduction was shown for cases diagnosed at early stages compared to later ones. During the pandemic, a significant increase in mortality was recorded among patients with chronic lymphocytic leukemia and multiple myeloma, while in cohorts of patients with chronic myeloid leukemia and Hodgkin lymphoma it increased slightly. The return of morbidity, mortality and prevalence rates to the original dynamics in 2022–2023 has been demonstrated.

Conclusion. This study demonstrated the features of the regional pattern of incidence, mortality, prevalence and gender-age characteristics of five hematological malignancies and provided the changes in the indicators dynamics of different hematological malignancies during the COVID-19 pandemic.

Background. Post-registration observational studies with switching therapy from the original drug to a biosimilar for non-medical indications allow us to assess the safety and effectiveness of this type of switching in real clinical practice.

Aim. Evaluation of the safety and effectiveness of non-medical switching from the original drug Keytruda® to the biosimilar drug Pembroria® in patients with various oncological pathologies in real clinical practice (REFLECTION).

Materials and methods. A retrospective analysis of data from electronic medical records from 21 medical institutions of the Russian Federation for the period 2020–2023 was carried out. Data were included from patients with cancer of various locations who received at least 2 injections of Keytruda® followed by switching to Pembroria® for non-medical indications (at least 2 injections). Primary criteria: incidence of immune-mediated adverse reactions (ImARs) of any severity. Secondary indicators: incidence of ImARs of various degrees of severity and infusion reactions, frequency of objective response rate (according to RECIST 1.1 criteria).

Results. The analysis included data from 382 patients (male/female 200/182, median age 62 years) with NSCLC (24.1%), RCC (23.3%), melanoma (20.4%) and cancer of other localization. Patients received Keytruda® on 1st and 2nd lines (54.2 and 25.4% of patients, respectively), on 3 or 4 lines (14.1%), or as part of adjuvant therapy (6.3%). 50.5% of patients received pembrolizumab as monotherapy. The median number of administrations was 7.0 and 5.0 for Keytruda® and Pembroria®, respectively. ImARs were registered in 44 (11.5%) patients (60 ImARs), including 40 ImARs in 35 (9.2%) patients while using Keytruda® and 20 ImARs in 17 (2.4%) patients with Pembroria®. The most common ImARs were hypothyroidism, hyperthyroidism, and hepatitis; the frequency of these ImARs was higher with Keytruda® (EAER for hypothyroidism 0.00422 and 0.00144, for hepatitis – 0.00124 and 0.00096, respectively). All 5 reported cases of hyperthyroidism in patients on Keytruda® (EAER 0.00124), were resolved before switching to Pembroria®. No infusion-related reactions or deaths due to ImARs have been reported. The objective response rate was comparable – 104 (32.6%) and 90 (29.2%) patients оn Keytruda® and Pembroria® therapy, respectively. Most patients maintained disease control after switching to Pembroria® [progression was recorded in 29 (9.4%) patients after switching to a biosimilar].

Conclusion. The safety profiles of Keytruda® and Pembroria® were satisfactory and comparable in this study. Switching from therapy with Keytruda® to Pembroria® is not accompanied by an increase in the frequency or severity of ImARs. Switching from Keytruda® to Pembroria® maintains disease control in most patients.

Introduction. Anti-PD-1 immunotherapy (IT) is becoming the standard treatment for patients with metastatic melanoma. However, immune checkpoint inhibitors are only effective in a fraction of patients, and studies examining biological markers and their correlation with clinical efficacy are insufficient to draw unambiguous conclusions.

Aim. To improve the outcomes of the first-line therapy for disseminated melanoma based on identifying clinical and immunohistochemical predictors of IT efficacy.

Materials and methods. Data from 130 patients who were treated with immune checkpoint inhibitors (nivolumab or prolgolimab) in the first-line therapy for disseminated melanoma between 2017 and 2024 were analyzed.

Results. Improvement was observed in 24 patients (18.4%): complete response in 18 patients (13.8%), partial response in 6 (4.6%), and stabilization in 71 (54.6%) patients. Progression was reported in 31 (24%) patients. Death occurred in 4 (3%) cases during IT with prolgolimab due to disease progression. The two-year disease-free survival (DFS) during IT was 53% (95% confidence interval [CI] 42–67), p=0.63; the median 2-year overall survival was not reached. In the immunohistochemical study, 47 (63.5%) patients had a predominance of tumor infiltration with CD8 lymphocytes over CD4, regardless of the IT type: 2-year DFS 82% (95% CI 70–96) vs 13% (95% CI 2.7–64) in the absence of CD8 predominance over CD4, p=0.0001; the median DFS was not reached in patients with the predominance of CD8 lymphocytes tumor infiltration over CD4 compared to the other group – 7.6 months in the absence of this feature (95% CI 5.8–0), p=0.001. The peritumoral location of the immune lymphoid infiltrate was observed in all 74 (100%) patients, and the intratumoral location was less common (52 patients, 70%). In the presence of both periand intratumoral location of the immune infiltrate, the 2-year DFS was 83% (95% CI 70–98) compared to the group of patients in whom no intratumoral location was detected – 5.5% (95% CI 0.8–36), p<0.0001. The expression of programmed cell death ligand 1 (PD-L1) level >10% was observed in 47 (63.5%) patients. With this level of PD-L1 expression, the one-year DFS was 91% (95% CI 83–100) compared to 29% (95% CI 15–57) with a lower level of PD-L1 expression, p<0.0001; the median DFS is reached, and in the group 2, DFS was only 6.6 months. In the case of PD-L1>10%, the 2-year DFS was high at 78% (95% CI 63–100), p<0.0001.

Conclusion. Based on the study's results, it can be assumed that immunohistochemical characteristics such as a PD-L1 expression level >10%, the simultaneous presence of periand intratumoral lymphoid tumor infiltration, and the predominance of CD8 over CD4 can be considered predictors of IT efficacy with nivolumab and prolgolimab.

Aim. To evaluate the efficacy and toxicity of second-line polychemotherapy according to FOLFOX or FOLFIRI regimen in patients with biliary tract tumours after progression during first-line chemotherapy (CT).

Materials and methods. The study is based on the analysis of retrospective and prospective data on the examination and treatment of 94 patients with biliary cancer of grades T1-4N0-2M0-1 followed-up and treated at the N.N. Blokhin National Medical Research Center of Oncology from 2015 to 2023. All patients were divided into 2 groups: Group 1 (FOLFOX, n=47) and Group 2 (FOLFIRI, n=47). In Group 1, patients received the recommended FOLFOX second-line CT regimen. Patients in Group 2 received FOLFIRI regimen. The endpoints were overall survival (OS) and incidence of grade 3-4 adverse events.

Results. The study included 94 patients. In the FOLFOX group, the median OS was 13.0 months (1-year OS was 57.8±7.4%); for the FOLFIRI group, the median OS was 12.3 months (1-year OS was 54.4±7.3%). The toxicity profiles of FOLFOX and FOLFIRI were acceptable and consistent with those reported for the regimens. According to the grade 3–4 toxicity data, diarrhea was significantly more common in the FOLFIRI group (p=0.014), and neurotoxicity was more common in the FOLFOX group (p=0.006). During the second-line CT, the frequency of grade 1–4 toxicities in the groups did not differ: 18 (38.3%) events in the FOLFOX group and 19 (40.0%) events in the FOLFIRI group.

Conclusion. Our results of evaluating the efficacy and toxicity of the second-line polychemotherapy regimens show that the FOLFOX and FOLFIRI CT regimens have equal efficacy in patients with advanced biliary tract cancer with a good performance according to the ECOG scale, who previously received the first-line therapy with a combination of gemcitabine with a platinum agent (cisplatin or oxaliplatin); also, our data demonstrate similar toxicity profiles of these regimens.

Background. The main method of treatment of desmoid fibromatosis is surgical, especially in patients with symptomatic disease or in cases of progression during the Look and Stay period. Due to the rarity of the disease, different localization, unpredictability of the clinical course, the lack of generally accepted clear criteria for choosing a treatment method and/or a sequence of treatment methods, the determination of prognostic criteria for the course of the disease is of great scientific and practical interest.

Aim. To study the immediate and long-term outcomes of surgical treatment in patients with retroperitoneal and abdominal desmoid fibromatosis.

Materials and methods. The study analyzed the data of 121 patients with histologically verified retroperitoneal and abdominal desmoid fibromatosis who underwent surgical treatment at the Blokhin National Medical Research Center of Oncology from 1999 to 2022.

Results. In 89% of cases, desmoid tumors are resectable; however, resections of adjacent organs are often required to remove the tumor mass completely. The frequency of combined interventions in the abdominal and retroperitoneal groups was 7.0 and 60.4%, respectively. Tumor cells along the edge of the incision are identified in 15.8% of patients, including 10% of patients with macroscopically detectable residual tumors. Surgical treatment of patients with desmoid tumors is associated with an acceptable complication rate and provides high rates of overall and relapse-free survival. Risk factors for disease-free survival of operated patients are retroperitoneal localization, multicentric tumor growth, and R2 category.

Conclusion. The treatment of patients with retroperitoneal and abdominal desmoid tumors should be carried out in specialized clinics with sufficient experience in performing surgical interventions, including combined ones. The treatment approach in patients with desmoid tumors should be selected by a multidisciplinary team based on personalized oncological and functional prognoses in accordance with the prognostic risk groups.

Uterine leiomyoma (ULM) is one of the most common gynecological pathologies in women of reproductive age. The prevalence of this pathology varies across different age groups, with approximately 10% in the 20–35 age range, increasing to 40–45% after the age of 35. ULM metastasis is an extremely rare phenomenon, with only 411 cases reported in the literature, including our 3 observations. Several definitions exist, with the most common being benign metastasizing ULM, found in both domestic and foreign literature. Each observation is crucial, as there are currently no clear treatment algorithms for this patient category. The study presents 3 cases of successful treatment of patients with metastatic ULM in two institutions. A systematic review of domestic and foreign literature on this pathology is conducted. Twenty-two clinical observations in the Russian Federation and neighboring countries are analyzed. Analysis of foreign literature revealed records of 386 clinical observations of benign metastasizing ULM. Benign metastasizing ULM of the uterus represents a rare nosological form. Systematization is advisable for determining the optimal treatment and observation tactics.

This publication is the Russian translation of the Plain Language Summary (PLS) of the Cochrane Systematic Review: Lee C-H, Wu Y-Y, Huang T-C, Lin C, Zou Y-F, Cheng J-C, Chen P-H, Jhou H-J, Ho C-L. Maintenance therapy for chronic lymphocytic leukaemia. Cochrane Database of Systematic Reviews 2024, Issue 1. Art. No.: CD013474. DOI: 10.1002/14651858.CD013474.pub2