Trastuzumab deruxtecan is an antibody–drug conjugate with high extracranial activity in human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer. We conducted the prospective, open-label, single-arm, phase 2 TUXEDO-1 trial. We enrolled patients aged ≥18 years with HER2-positive breast cancer and newly diagnosed untreated brain metastases or brain metastases progressing after previous local therapy, previous exposure to trastuzumab and pertuzumab and no indication for immediate local therapy. Patients received trastuzumab deruxtecan intravenously at the standard dose of 5.4 mg per kg bodyweight once every 3 weeks. The primary endpoint was intracranial response rate measured according to the response assessment in neuro-oncology brain metastases criteria. A Simon two-stage design was used to compare a null hypothesis of <26% response rate against an alternative of 61%. Fifteen patients were enrolled in the intention-to-treat population of patients who received at least one dose of study drug. Two patients (13.3%) had a complete intracranial response, nine (60%) had a partial intracranial response and three (20%) had stable disease as the best intracranial response, with a best overall intracranial response rate of 73.3% (95% confidential interval 48.1–89.1%), thus meeting the predefined primary outcome. No new safety signals were observed and global quality-of-life and cognitive functioning were maintained over the treatment duration. In the TUXEDO-1 trial (NCT04752059, EudraCT 2020-000981-41), trastuzumab deruxtecan showed a high intracranial response rate in patients with active brain metastases from HER2-positive breast cancer and should be considered as a treatment option in this setting.

Brain metastases (BM) are frequently diagnosed in metastatic Her2-positive breast cancer. Local treatment remains the standard of care but lapatinib plus capecitabine was recently established as systemic therapy option. Due to a disruption of the blood-brain/tumour-barrier at metastatic sites, even large molecules may penetrate into the central nervous system (CNS). Here, we report on the activity of T-DM1 in Her2-positive breast cancer BM. T-DM1 was administered at a dose of 3.6 mg once every 3 weeks as primary systemic therapy for BM or upon documented CNS progression after initial local treatment. Thus, this study allowed for the appraisal of T-DM1 activity in BM. Restaging was conducted every 12 weeks with MRI or whenever symptoms of disease progression occurred. Ten patients were included; in two asymptomatic subjects, T-DM1 was administered as primary therapy, while eight had progressive BM. All patients had received prior treatment with trastuzumab, six had already received lapatinib, and three pertuzumab as well. Three patients had partial remission of BM, and two patient had stable disease lasting for ≥6 months; two further patients had stable disease for <6 months while three progressed despite treatment. At 8.5 months median follow-up, intracranial PFS was 5 months, and median OS from initiation of T-DM1 was not reached. Local treatment of BM remains the standard of care; lapatinib plus capecitabine is currently the best established systemic therapy option. Still, T-DM1 apparently offers relevant clinical activity in BM and further investigation is warranted.

Porocarcinoma is a very rare malignant tumor arising from the duct of eccrine sweat glands. Its prognosis is variable. We report on a patient who developed lymph node and multiple distant metastases, and who died of this malignancy only 6 months after the initial diagnosis.

Purpose: Brain metastases (BMs) are a rare but devastating condition in estrogen receptor (ER)-positive metastatic breast cancer (MBC). Although endocrine therapy (ET) is the mainstay of treatment in this disease subtype, only case reports have been published concerning the activity of ET in BMs henceforth. Therefore, we aimed to systematically investigate the impact of ET after diagnosis of BM on outcome and clinical course of disease in patients with ER-positive MBC.Experimental Design: Patient characteristics, detailed information about BMs including diagnosis-specific graded prognostic assessment class (DS-GPA), and clinical outcome were obtained by retrospective chart review for all patients treated for ER-positive breast cancer BMs between 1990 and 2017 at an academic care center. Overall survival (OS) was measured as the interval from diagnosis of BM until death or last date of follow-up.Results: Overall, 198 patients [female: 195/198 (98.5%); male: 3/198 (1.5%)] with ER-positive breast cancer BMs were available for this analysis. Eighty-eight of 198 patients (44.4%) received ET after diagnosis of BM including aromatase inhibitors (AIs; letrozole, anastrozole, exemestane), tamoxifen, and fulvestrant. Median OS was significantly longer in patients receiving ET after diagnosis of BM compared with patients who did not (15 vs. 4 months, P < 0.001; log-rank test). No significant difference in terms of OS was observed between patients receiving AIs, tamoxifen, or fulvestrant. In patients with concomitant leptomeningeal carcinomatosis (LC), ET prolonged median OS significantly as well (7 vs. 3 months, P ¼ 0.012; log-rank test). In a multivariate analysis including DS-GPA and ET, only treatment with ET after diagnosis of BM (HR, 0.69; 95% confidence interval, 0.48-0.99; P ¼ 0.046) was associated with prognosis (Cox regression model).Conclusions: Continuing ET after BM diagnosis was associated with a significantly prolonged OS in this large singlecenter cohort. No substantial differences between substances were observed. These findings should be validated in a prospective cohort.