[Monoclonal gammopathy of renal significance: consensus of hematologists and nephrologists of Russia on the establishment of nosology, diagnostic approach and rationale for clone specific treatment].

Monoclonal gammopathy of renal significance (MGRS) is a new nosology in modern nephrology and oncohematology. MGRS is defined as kidney injury due to nephrotoxic monoclonal immunoglobulin produced by the B-cell line clone which does not reach the hematological criteria for specific treatment initiation. Monoclonal proteins pathological effects on kidney parenchyma result in irreversible decline of kidney function till the end stage renal disease that in line with the position of International Consensus of hematologists and nephrologists determinates critical necessity for clone specific treatment in patients with MGRS despite the absence of hematological indications for treatment initiation. Main challenge of MGRS in Russian Federation is an inaccessibility of an in-time diagnostic and appropriate treatment for the great majority of patients due to the following reasons: 1) limited knowledge about the MGRS among hematologists and nephrologists; 2) lack of necessary diagnostic resources in most health-care facilities; 3) lack of approved clinical recommendations and medical economic standards for treatment of this pathological entity. Consensus document comprises the opinion of experts leading nephrologists and hematologists of Russian Federation on the problem of MGRS including the incoherence in nosology classification, diagnostics approach and rationale for clone specific treatment. Consensus document is based on conclusions and agreements reached during the conference of leading nephrologists and hematologists of Russia which was held in the framework of symposia Plasma cell dyscrasias and lymphoproliferative diseases: modern approaches to therapy, 1516 of March 2019, Pavlov First Saint Petersburg State Medical University. The present Consensus is intended to define the principal practical steps to resolve the problem of MGRS in Russian Federation that are summarized as final clauses.

[Role of clustered HER2/neu amplification as a marker for a special sensitivity to neoadjuvant anti-HER2 therapy with trastuzumab in patients with stage II-III breast cancer]. / Rol' klasternoi amplifikatsii gena HER2/neu kak markera 'osoboi' chuvstvitel'nosti k neoad''iuvantnoi anti-HER2-terapii trastuzumabom pri rake molochnoi zhelezy II­III stadii.

OBJECTIVE: To evaluate the influence of clinical and morphological factors and HER2 copy numbers on pathologic complete response (pCR) rates in patients with HER2-positive stage II-III breast cancer (BC). MATERIAL AND METHODS: Treatment results were studied in 73 patients with HER2-positive Stage II-III BC, who received treatment at the N.N. Blokhin National Medical Research Center of Oncology in 2015 to 2018. Treatment included neoadjuvant chemotherapy (NACT) with HER2-blockade and radical surgery followed by the evaluation of a pathologic response in the primary tumor and regional lymph nodes. The patients` age varied from 29 to 71; its median was 51.5; 45.2% of patients had primary operable stages (T1-3N0-1) and 54.8% had locally advanced tumors. All the patients had grade 2-3 anaplasia; luminal HER2-positive BC was diagnosed in 41.4% of patients; hormone-negative tumors were seen in 58.9%; 91.5% of patients had Ki-67 ≥20% in 75.3% of patients, preoperative systemic therapy included anthracycline-containing regimens (4AC + 4 x paclitaxel 175 mg/m2/12 × weekly administrations of paclitaxel 80 mg/m2; trastuzumab therapy was simultaneously performed with the administration of taxanes in the standard regimen) and anthracycline-free regimen TCH ± Pertuzumab regimen in 24.7% of cases. After NACT patients underwent surgery (radical mastectomy in 78.1%, breast-sparing treatment in 21.9%) with the assessment of morphological findings. Biopsy specimens obtained before the treatment was restudied; HER2 amplification was detected using a Dako HER2 IQFISH pharmDx kit according to its instruction and the 2018 ASCO/CAP guidelines. In 87.1% of cases, the HER2-positive status corresponded to the first category of the 2018 ASCO/CAP criteria for HER2-positive BC; clustered HER2 amplification was found in 30.1% of cases. The authors analyzed the frequency of bpCR and tpCR attainment by various clinical and morphological factors, as well as the impact of a HER2 amplification level on pCR rates. RESULTS: A breast pCR (bpCR) was achieved in 57.4% patients; bpCR and lymph node CR (lnCR) were noted in 48.9% patients. The rates of bpCR significantly depended on female age, chemotherapy regimen, addition of Pertuzumab, and HER2 copy number. That of bpCR in women less than 35 years of age, in those aged 36-50 years, and in those aged older than 50 years was 22.2, 57.7 and 71.9%, respectively (p=0.026). The maximum bpCR rate observed with the TCH±P regimen was 80.0%, that with anthracycline-containing regimes was 52.8% (p=0.045), and the addition of Pertuzumab increased complete response rates up to 88.9% (that with Trastuzumab was 54.2% (p=0.049). The relationship of bpCR rates to the detection of cluster amplification turned out to be highly significant (81% in its detection and 48.9% in its absence (p=0.013). In addition, clustered HER2 amplification was the only significant predictive factor for complete regression in the primary tumor and lymph nodes: in its presence, the tpCR rate reached 68.8% versus 38.7%. CONCLUSION: Clustered amplification of the HER2 gene is the most significant factor of sensitivity to anti-HER2 therapy for Stage II-III BC, and is associated with the maximum rate of both bpCR and total pCR. Further study of this factor may assist in optimizing the treatment algorithm for HER2 + BC.

[Role of biological heterogeneity in recurrent and metastatic breast cancer]. / Rol' biologicheskoi geterogennosti pri retsidiviruiushchem i metastaticheskom rake molochnoi zhelezy.

Breast cancer (BC) is a heterogeneous tumor, the biological characteristics of which vary with its growth and progression. Information on key tumor receptors (ER, PR, HER2, and Ki-67) is the basis for individualizing the diagnostic and treatment algorithm at all BC stages; however, the feasibility of biopsy of distant metastases and the re-testing of the biological subtype of BC in its suspected progression are being actively discussed in clinical practice. This review presents an update on the features of metastasis in different biological BC subtypes and assesses the clinical and prognostic role of biopsy of distant metastases in the lung, bones, liver, and brain. It shows the frequency of discordance in receptor status between primary and recurrent tumors at different sites of metastases, as well as the impact of changes in receptor status on survival rates in different biological BC subtypes. The relevance of performing biopsies in BC progression is shown to be beyond question, because it makes it possible to confirm the fact that the disease progresses, to re-test the biological subtype of recurrent BC, and to find new targets that allow the most effective drug treatment regimens to be used.