Copy Number Aberration Analysis to Predict Response to Neoadjuvant Anti-HER2 Therapy: Results from the NeoALTTO Phase III Clinical Trial.

PURPOSE: The heterogeneity of response to anti-HER2 agents represents a major challenge in patients with HER2-positive breast cancer. To better understand the sensitivity and resistance to trastuzumab and lapatinib, we investigated the role of copy number aberrations (CNA) in predicting pathologic complete response (pCR) and survival outcomes in the NeoALTTO trial. EXPERIMENTAL DESIGN: The neoadjuvant phase III NeoALTTO trial enrolled 455 patients with HER2-positive early-stage breast cancer. DNA samples from 269 patients were assessed for genome-wide copy number profiling. Recurrent CNAs were found with GISTIC2.0. RESULTS: CNA estimates were obtained for 184 patients included in NeoALTTO. Among those, matched transcriptome and whole-exome data were available for 154 and 181 patients, respectively. A significant association between gene copy number and pCR was demonstrated for ERBB2 amplification. Nevertheless, ERBB2 amplification ceased to be predictive once ERBB2 expression level was considered. GISTIC2.0 analysis revealed 159 recurrent CNA regions. Lower copy number levels of the 6q23-24 locus predicted absence of pCR in the whole cohort and in the estrogen receptor-positive subgroup. 6q23-24 deletion was significantly more frequent in TP53 wild-type (WT) compared with TP53-mutated, resulting in copy number levels significantly associated with lack of pCR only in the TP53 WT subgroup. Interestingly, a gene-ontology analysis highlighted several immune processes correlated to 6q23-24 copy number. CONCLUSIONS: Our analysis identified ERBB2 copy number as well as 6q23-24 CNAs as predictors of response to anti-HER2-based treatment. ERBB2 expression outperformed ERBB2 amplification. The complexity of the 6q23-24 region warrants further investigation.

TiLoop Bra Assisted Breast Reconstruction - Our Experience.

Additional covering of the lower pole with allomaterial or its synthetic analogues during immediate breast reconstruction is being perfomed at the N.N. Petrov National Medical Research Oncology Center, Ministry of Healthcare of Russian Federation for last 7 years. Initially, epidermal flap was the only option for lower pole coverage, later ADM was used as part of clinical approbation. Average complication rate ranges from 20-35% due to blood circulatory (supply) disorders. Since 2018, a titanized mesh (TiLoop Bra) been used as a additional coverage of the lower pole. Methods: From July 2018 to April 2019, 103 breast reconstructions were performed using TiLoop-BRA mesh. All operations were performed due to malignant tumors of breast, of which in 94 operations were performed for unilateral breast carcinoma, 9 for bilateral breast carcinoma.74 patients received neoadjuvant therapy, 31 received adjuvant therapy, 17 patients required radiation therapy. Results: Overall complications rates significally decreased. Complete loss of breast implant and mesh endoprosthesis 5.88%, Capsular contracture 17.65 %, Only mesh removal due to painful syndrome 5.88%,* Red breast * syndrome (by analogy with ADM) 5.88%.

Comparison of two treatment strategies for irradiation of regional lymph nodes in patients with breast cancer: Lymph flow guided portals versus standard radiation fields.

AIM AND BACKGROUND: Radiotherapy being an essential part of breast cancer treatment, we evaluate various radiotherapy strategies in patients with breast cancer. MATERIALS AND METHODS: Lymph node (LN) scintigraphy was performed in 172 primary patients with BC. LN visualization started 30-360 min after intratumoral injection of 75-150 MBq of 99mTc-nanocolloids. Our standard recommendation for postoperative radiotherapy in patients with LN invasion by BC were as follows: for patients with external localization of tumour - breast + axillary (Ax) + sub-supraclavicular (SSCL) regions; with internal localization - all above + internal mammary nodes (IM). Proposed strategy of lymph flow guided radiotherapy is based on the assumption that only regions that contain 'hot' LNs must be included in a treatment volume. RESULTS: Among 110 patients with external localization of BC, Ax LNs were visualized in all cases and in 62 patients it was the only region with 'hot' LN. Twenty-three patients (20.9%) had drainage to Ax + SSCL, 12 (10.9%) - Ax + IM, 13 (11.8%) - Ax + SSCL + IM regions. After the visualization of lymph flow patterns, standard treatment volume was changed in 87/110 cases (79.1%): in 56.4%, reduced, in 22.7%, enlarged or changed. In 62 patients with tumours in internal quadrants, we revealed the following patterns of lymph-flow: only to the Ax region in 23 (37.1%); Ax + IM, 13 (21%); Ax + SSCL, 15 (24.2%); Ax + IM + ISSCL, 11 (17.7%) cases. After lymph-flow visualization, the standard irradiation volume was reduced in 53/62 (85.5%) cases. CONCLUSION: Visualization of an individual lymph flow pattern from BC can be used for the optimization of standard fields used for irradiation of regional LNs.