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.

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%).

The role of systemic treatment after whole brain radiotherapy (WBRT) in breast cancer patients with brain metastases: Differences depending on biological subtype

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Background: The aim of the study was to analyze the efficacy of systemic treatment (chemotherapy [chth], endocrine therapy, targeted therapy) performed after WBRT in patients (pts) with breast cancer and brain metastases. Methods: The group of 222 consecutive breast cancer pts with brain metastases treated in one institution in the years 2003–2006 was divided into four biological subgroups based on ER, PR, and HER-2 receptors’ expression: HER-2(+++)ER/PR(-); HER-2(+++)ER/PR(+); ER(-)PR(-)HER-2(-); and ER/PR(+)HER-2(-). WBRT was performed in 219 (99%) pts. Systemic therapy after WBRT was continued in 160 (72%) pts. Clinically, patients with triple-negative breast cancer were more often in poor performance status (KPS<60%) than the others (51% vs. 28%, respectively). Survivals from brain metastases without and with systemic treatment were compared in four mentioned biological subgroups. Results: Median survival from brain metastases in the entire group was 7.5 months. In the group of ER/PR(+)HER-2(-) median survival without and with systemic therapy was 3 and 14 months, respectively (p = 0.007). In the group of HER-2(+++)ER/PR(+) median survival without further treatment, after chth and after chth with trastuzumab was 2, 8, and 13 months, respectively (p = 0.000) and in the group of HER-2(+++)ER/PR(-) median survival without further treatment, after chth and after chth with trastuzumab was 4, 8, and 10 months, respectively (p = 0.004). In triple-negative breast cancer patients median survival without and with chemotherapy was 3 and 4 months, respectively (p = 0.75). Conclusions: Systemic treatment (chth, endocrine therapy, targeted therapy) continued after WBRT in breast cancer pts with brain metastases prolongs survival in three of four biological subgroups. In the group of HER-2-positive breast cancer pts, trastuzumab added to chth had independent positive impact on survival. No benefit was observed in the subgroup of triple-negative breast cancer pts; it would be the result of refractory disease and the fact, that more pts were in poor performance status.

No significant financial relationships to disclose.

Effect of early detection of occult brain metastases in HER2-positive breast cancer patients on survival

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Aim: The aim of the study was to compare disease free survivals (DFS), survivals from the detection of brain metastases, overall survivals (OS) and the causes of death between two patient groups: group I with disseminated HER2-positive breast cancer and occult brain metastases and group II with symptomatic brain metastases. Material and Methods: MRI screening of the brain was performed in 80 HER2-positive breast cancer pts treated with trastuzumab and cytostatics for visceral metastases. In 29 pts (34%) in whom occult brain metastases were detected, whole brain radiotherapy (WBR) to the brain (30 Gy in 10 fractions) was performed (Group I). They were compared with 48 pts with symptomatic brain metastases treated at the same clinic during the same time period (Group II). Both groups were comparable regarding the site of distant metastases and the type of treatment. All pts in both groups had distant metastases to the lung and/or liver. Results: Median DFS in group I was 17 months and in Group II- 19.9 months (p=0.61). Median survival from dissemination of the disease (visceral metastases) to the detection of occult and symptomatic brain metastases was 9 and 15 months, respectively (p=0.21). Median survival calculated from the detection of brain metastases was 9 and 9.3 months, respectively (p=0.76). Median OS of pts with occult and symptomatic brain metastases was 53.8 and 52 months, respectively (p=0.79). In the group with occult brain metastases 15% of pts died because of progression in the brain and in the group of symptomatic brain metastases the rate of cerebral death was 48%. Conclusions: WBR performed during the asymptomatic period decreased the rate of cerebral deaths, but did not prolong overall survival. Screened MRI of the brain during the asymptomatic period did not improve the outcome of pts with HER2-positive breast cancer and with visceral metastases.

No significant financial relationships to disclose.