Trastuzumab biosimilar (Kanjinti) in breast cancer patients: One-center retrospective observational study

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Background: The switch of anti-HER2 therapy from the reference drug Herceptin to a biosimilar has presented challenges to the clinics. Real world data on trastuzumab biosimilars are very limited or not available. In our clinic we perform observational retrospective study to confirm safety and efficacy Kanjinti. Methods: 195 patients (pts) with HER2-positive breast cancer were treated with Kanjinti from Jul.18. 2018 to Jan.29.2020. Cardiac events (↓LVEF) and other unexpected or serious adverse events were monitored in all pts. 34 pts received carboplatin, docetaxel pertuzumab and trastuzumab biosimilar in neoadjuvant setting, 99 received trastuzumab biosymilar in monotherapy or with other cytostatic drugs in neoadjuvant or adjuvant setting, and 62 received docetaxel, pertuzumab and Kanjinti in metastatic setting. Results: Pertuzumab was used in combination with Kanjinti in 49% of pts (32% in the 1st. line of palliative tretment and 17% in the neoadjuvant settings, respectively).Switching from Herceptin to Kanjinti was observed in 65% of MBC patients and 37% of EBC patients. Switching was done at a median of 4th cycle. 6 patients had a decline in LVEF. No other trastuzumab related adverse events was observed. Conclusions: The management of HER2 positive breast cancer in our clinic follows the international recommendations. This is the first real world safety data of Kanjinti from Poland. The 12-month follow-up treatment with Kanjinti an acceptable cardiac safety profile. In cases where there was a switch from Herceptin to Kanjinti or Kanjinti combined with pertuzumab, the safety profile was similar to that previously reported in other studies.

Oral etoposide in heavily pre-treated metastatic breast cancer: A retrospective study

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Background: Patients with metastatic breast cancer can derive clinical benefit from several subsequent lines of chemotherapy. However, in heavily pre-treated patients, agents with clinical activity, a favourable side effects profile and a convenient administration modality are preferred. Oral etoposide may be an interesting treatment option in this group of patients. Methods: This was a retrospective observational study performed in single institution in 22 patients with MBC refractory to prior anthracycline, taxane, and capecitabine therapy. All patients were treated with oral etoposide at 50 mg/day on days 1-20. Treatment cycles were repeated every 28 days. Results: The median age were 53 years (42-68). The median number of previous chemotherapy lines was 5 (range 2-7). There were no complete or partial responses. Median PFS was 7 months. In 5 patients, the disease stabilized for over 12 months. Interestingly, etoposide activity was unrelated to the number of previous lines and type of metastatic involvement. Oral etoposide was well tolerated with only one patients discontinuing therapy due to toxicity. Conclusions: In real practice oral etoposide is a valuable and safe option for pre-treated metastatic breast cancer patients and might be considered in patients failing other approaches, but still suitable for chemotherapy.

Assessment of the treatment results in patients with breast cancer coexisting with pregnancy: A single-center observational study

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Background: This study discusses the analysis of the prospectively collected material on pregnant patients treated for breast cancer at the Department of Breast Cancer and Reconstructive Surgery of the Maria Skłodowska-Curie National Oncology Institute - National Research Institute (until 2020: Oncology Center - Institute) in Warsaw, in the years 1995 - 2020. 84 patients were included into the final analysis and 72 children were assessed simultaneously. Methods: The paper summarizes information on the diagnosis and treatment of breast cancer during pregnancy, the course of pregnancy and childbirth and the birth parameters of children i.e. weight, length and Apgar score, as well as the dependencies between them, mainly the impact of some breast cancer, diagnosis and treatment process features on the newborns. The patietnt’s survavial - DFS ( disease free survival) and OS ( overall survival) - was also analyzed. The course of breast cancer diagnosis and treatment data were obtained from the patients’ medical documentation (medical records) and from information provided by the mothers during follow-up visits and read in the children's health books. In order to answer the research questions, statistical analyzes were conducted using the IBM SPSS Statistics 26 package. Results: In the analyzed period, the disease recurrence was recognized in 34 (40.5%) patients, and 24 (28.6%) patients died. The median disease-free survival (DFS) was 12.3 years (147.5 months), and the median overall survival (OS) was not reached during the follow-up period. The estimated 5-year survival rates for DFS and OS were 57.9% and 74.5% respectively, and for 10-year survival - 51.4% and 64.5%. The study showed a statistically significant relationship between the baseline clinical advancement and DFS. It has been also analyzed how the diagnosis, treatment and method of pregnancy termination changed in two time periods (1995-2012 and 2013-2020). There were no statistically significant differences in survival - both DFS and OS - between the group of patients treated before and after 2012. In the assessment of the impact of some factors on the birth children parameters (weight and length), statistically significant results were obtained for: pregnancy advancement at diagnosis, breast cancer stage at diagnosis, pregnancy advancement at the start of chemotherapy, the chemotherapy regimen (classic or dose-dense), the number of cycles of chemotherapy given during pregnancy, and the number of drugs used in supportive treatment. Conclusions: The entire analysis has become not only an insightful characteristic of the studied group, but also these results may be important in everyday clinical practice and may help to optimize the management of an extremely complex and difficult situation, which is the coexistence of pregnancy with a malignant disease that threatens the mother’s life.

Clinical value of kinase Aurora-A serum level determination in patients with breast cancer qualified for neoadjuvant chemotherapy: Pilot study

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Background: Aurora A (AURKA) is serine/threonine kinase that plays a regulatory role in mitosis and multiple signaling pathways. Overexpression of AURKA has been found in many solid tumors including breast cancer. It also has been found to be a prognostic marker indicating resistance to taxane treatment and poor prognosis in ER positive breast cancer. The aim of this study is to assess clinical value of Aurora-A serum level determination in patients with breast cancer qualified for neoadjuvant chemotherapy. Methods: 60 patients with confirmed breast cancer before treatment were qualified for the study, aged 31-77 (median 52 years), including 30 premnopausal and 30 pomenopausal. The control group consisted of 30 healthy women aged 20-80 (median 53 years). Clinical and pathological features were determined in a selected group of patients with breast cancer who subsequently underwent preoperative chemotherapy, i.e. tumor size (T), lymph node status (N), presence of distant metastases (M), estrogen receptor status (ER) and progesterone (PgR), HER2 receptors and Ki 67 proliferative index. The blood serum of the examined patients and healthy women was determined by the enzyme-linked ELISA method in doublets of the AURKA biomarker concentration. Mann-Whitney test and ROC curve analysis were used for statistical calculations. Results: No significant differences were found between the concentrations of AURKA in breast cancer patients and in the control group. In both analyzed groups there were no significant differences in biomarker levels depending on the menopausal status. When assessing the relationship between AURKA concentrations and clinical-pathological features, significant differences were found depending on the state of the lymph nodes (N0 vs N1 + N2) (p = 0.006). There was no correlation between the concentrations of the tested biomarker and the tumor size (T), the state of receptors and the Ki67 index. In patients with a lack of receptors (triple negative vs others), higher levels of Aurora A (p = 0.06) in the blood serum were observed at the level of the statistical trend. Conclusions: The preliminary results obtained indicate the potential usefulness of determining the concentration of the new biomarker Aurora A in the blood serum of patients with breast cancer. The research is continuing.

Prognostic and predictive value of neutrophil/lymphocyte ratio in patients with triple-negative and HER2-positive breast cancer undergoing neoadjuvant systemic therapy

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Background: Preoperative neutrophil-lymphocyte ratio (NLR) have been suggested to be correlated with the prognosis of patients with breast cancer (BC). However, the results still remain controversial. The goal of our study was to evaluate the predictive and prognostic value of NLR in early stage triple negative and HER2-pos breast cancer patients undergoing NAC. Methods: 96 female patients (pts) with histologically proven breast cancer (51 TNBC, and 45 HER2 pos) were analysed in this retrospective analysis. The NLR before the initiation of NAC was documented. Histopathological response in surgically removed specimens was evaluated using the Residual Cancer Burden (RCB) Calculator (by MD Anderson Cancer Center). The pCR was defined as no invasive tumor in primary tumor bed and lymph nodes. The NLR variable was analyzed as both continuous and categorical. The impact on pCR and RCB was tested using Mann-Whitney, Kruskal-Willis or the Chi-2 test, respectively. Results: Only 4 categories of NAC were used: in TNBC 4 x ACdd followed by 12 x PCL (38 pts) or 4 x ACdd followed by 12 x PCL+ carboplatin AUC 1.0-2 (13 pts), in HER2-pos 39 pts received 6 x TCH (docetaxel + tratuzumab + carboplatin AUC 6) and 6 pts 4 x ACdd followed by 12 x PCL iv + 4 x trastuzumab. In 27 pts (53%) with TNBC and 24 pts (53%) with HER2-pos breast cancer pCR was obtained after NAC. RCB distribution was: 0-53.1%, 1-22%, 2-17.6%, 3-7.3%. No association with NLR and pCR could be observed (p > 0.26). No association with NLR and RCB could be observed (p > 0.18). Conclusions: In our retrospective analysis we could not demonstrate predictive or prognostic value of NLR in the cohort of early stage triple negative and HER2-positive breast cancer patients treated with NAC. Further studies are planned in a group of patients with Luminal B, HER2 – negative breast cancer, who received NAC.

Validation of the Van Nuys Prognostic Index in 737 patients with ductal carcinoma in situ (DCIS) treated at Maria Sklodowska-Curie National Research Institute of Oncology, Warsaw, Poland

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Background: To assess the value of the Van Nuys Prognostic Index (VNPI) used in Maria Sklodowska-Curie National Research Institute of Oncology (MSCNRIO) to select the most adequate method of the treatment of DCIS patients. Methods: The database covered 737 subsequent DCIS patients treated in MSCNRIO in the years 1996 -2011. The results of the treatment with and without compliance with the VNPI index were compared. Results: In the group of 737 patients 66 (9%) failures were reported. There were 4 (0.5%) deaths due to DCIS progression. After 15 years of observation of patients treated in compliance with VNPI, the percentage of failures after local excision (4-6 VNPI points), breast conserving treatment (7-9 VNPI points) and mastectomy (10-12 VNPI points) was 29%, 21% and 9%, respectively. No differences in the overall survival was observed. In patients with 4-6 VNPI points the percentage of recurrences in the group treated in compliance with the VNPI (without radiotherapy) was 29% while in the group treated without compliance with the VNPI (with radiotherapy) - 2%. Conclusions: The Van Nuys prognostic index (VNPI) does not seem to be an ideal tool in patients with DCIS. It shows too high percentage of recurrences in the low risk group (VNPI of 4, 5 or 6 points), treated exclusively with a sparing surgery. Almost all patients after surgical excision should be irradiated.

Pathological outcomes of HER2-positive early breast cancer patients treated with neoadjuvant trastuzumab or dual anti-HER2 therapy and carboplatin with docetaxel: A Maria Sklodowska-Curie National Research Institute of Oncology experience

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Background: Pathological complete response (pCR) after neoadjuvant chemotherapy (NACT) for breast cancer predicts the risk of recurrence and increasingly may indicate the need for additional therapy postoperatively. Methods: A retrospective analysis was performed in two cohorts of patients (pts) treated with docetaxel, trastuzumab and carboplatin (TCH) or with docetaxel, carboplatin and dual blockade (TCH-P) in the neoadjuvant setting in patients with early breast cancer (tumor size < 50 mm and > 10 mm and cN0 or cN1) in our Clinic, and who had definitive surgery was conducted. Demographic data, size, grade, tumor type, receptor status prior to neoadjuvant treatment, pathological complete response (pCR) rates, and adverse effects were analyzed. The pCR was defined as ypT0 ypN0. Results: Patient in cohort A (n = 58) received TCH x 6 cycles and in cohort B (n = 25) TCH-P x 6 cycles. Median age was 51 (range 23 to 76 years) in cohort A and 46 (range: 30-68) in cohort B. In cohort A 37 (64%) of pts was HR-positive, in cohort B only 9 (36%) pts . The most common adverse events in both groups were neutropenia, diarrhea, chemotherapy induced polyneuropathy and febrile neutropenia. There are no significant differences in the frequency of adverse events in two cohorts. There was no symptomatic heart failure, but 6 pts (10%) in cohort A and 5 pts (16%) in cohort B had > 10% asymptomatic decrease in LVEF. All patients were evaluable for pCR. Higher rates of pCR were achieved in the HER2pos/HRneg pts: 66% (n = 14) in cohort A, and 87% (n = 14) in cohort B. In group HER2pos/HRpos pts, the pCR rate was 48% (n = 18) vs 55% (n = 5) respectively. Conclusions: In HER2positive early breast cancer, a dual blockade (trastuzumab and pertuzumab) together with carboplatin and docetaxel neoadjuvant chemotherapy achieved higher rates of pCR ( 76%) compared with pts treated with trastuzumab, carboplatin and docetaxel (56%). However, a much higher percentage of pCR was observed in the group of patients with non-luminal cancers, who received a double blockade (87% vs 66%).

Abstract P4-15-12: Evaluating the significance of the Van Nuys prognostic index for the management of ductal carcinoma in situ – one center's experience

Aim: This was to assess the treatment outcomes of ductal carcinoma of the breast (DCIS) based on the Van Nuys Prognostic Index.

Material and Methods: 634 consecutive patients with DCIS were treated at the Warsaw Cancer Center, Poland between 1996 and 2008 based on the VNPI score. Tumorectomy without radiotherapy (T) was performed in 123 (20%) patients, breast conserving treatment (BCT) in 206 (32%) and mastectomy (M) in 305 (48%). Disease-free survival (DFS) and overall survival (OS) were analysed within 3 groups and a multivariate analysis was performed to determine the most important factor affecting local relapse.

Results: 5-year, 10-year and 15-year DFS in the M group were respectively 98%, 97% and 97% whilst 5-year, 10-year and 15-year DFS in the BCT group were respectively 91%, 87% and 80%. 5-year, 10-year and 15-year DFS in the T group were respectively 92%, 73% and 67%. Local recurrence was observed in 54 patients. In 40% cases this was noninvasive and in 60 % invasive. Only 4 of 54 patients with recurrence died due to breast cancer. 5-year, 10-year and 15-year OS in the M group were respectively 96%, 92% and 89%. 5-year, 10-year and 15-year OS in the BCT group were respectively 99%, 94% and 85%. 5-year, 10-year and 15-year OS in the T group were respectively 95%, 90% and 73% (p=0.422). Tumor size assessed by mammography was the only variable affecting DFS.

Conclusions: Treatment outcomes of DCIS based on the Van Nuys Prognostic Index are comparable with those cited the literature, however, the recurrence rate in the T group seems to be very high. This group requires that new risk factors be sought for prior to taking a treatment decision.

Citation Format: Niwinska A, Galecki J, Nagadowska M, Piechocki J, Kunkiel M, Jagiello-Gruszfeld AI, Nowecki Z. Evaluating the significance of the Van Nuys prognostic index for the management of ductal carcinoma in situ – one center's experience [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-15-12.