Long-term complete response to intrathecal trastuzumab in a patient with leptomeningeal carcinomatosis due to her2- overexpressing breast cancer: Case report

Therapies beyond Physiological Barriers and Drug Resistance: A Pilot Study and Review of the Literature Investigating If Intrathecal Trastuzumab and New Treatment Options Can Improve Oncologic Outcomes in Leptomeningeal Metastases from HER2-Positive Breast Cancer

Leptomeningeal metastases (LM) are a rare but rapidly fatal complication defined by the spread of tumor cells within the leptomeninges and the subarachnoid space, found in approximately 10% of patients with HER2-positive breast cancers. This pilot study evaluated the efficacy of local treatment with intrathecal Trastuzumab (IT) added to systemic treatment. The oncologic outcome of 14 patients with HER2-positive LM is reported. Seven received IT, and seven received standard of care (SOC). The mean number of IT cycles administered was 12.14 ± 4.00. The response rate to CNS after IT treatment + SOC was 71.4%, and three patients (42.8%) obtained durable responses lasting more than 12 months. The median progression-free survival (mPFS) after LM diagnosis was six months, and the median overall survival (mOS) was ten months. The mean values of the PFS in favor of IT therapy (10.6 mo vs. 6.6 mo) and OS (13.7 vs. 9.3 mo) suggest a non-negligible investigation direction in the sense of exploiting intrathecal administration as a possible treatment modality in these patients. Adverse events reported were local pain related to intrathecal administration and one case of arachnoiditis, hematoma, and CSF fistulae. Intrathecal administration of Trastuzumab, alongside systemic treatment and radiotherapy, might improve oncologic outcomes in LM HER2-positive breast cancer with manageable toxicity.

Advances in Intraoperative Flow Cytometry

Flow cytometry is the gold-standard laser-based technique to measure and analyze fluorescence levels of immunostaining and DNA content in individual cells. It provides a valuable tool to assess cells in the G0/G1, S, and G2/M phases, and those with polyploidy, which holds prognostic significance. Frozen section analysis is the standard intraoperative assessment for tumor margin evaluation and tumor resection. Here, we present flow cytometry as a promising technique for intraoperative tumor analysis in different pathologies, including brain tumors, leptomeningeal dissemination, breast cancer, head and neck cancer, pancreatic tumor, and hepatic cancer. Flow cytometry is a valuable tool that can provide substantial information on tumor analysis and, consequently, maximize cancer treatment and expedite patients’ survival.

The influence of the blood-brain barrier in the treatment of brain tumours

Brain tumours have a poor prognosis and lack effective treatments. The blood-brain barrier (BBB) represents a major hurdle to drug delivery to brain tumours. In some locations in the tumour, the BBB may be disrupted to form the blood-brain tumour barrier (BBTB). This leaky BBTB enables diagnosis of brain tumours by contrast enhanced magnetic resonance imaging; however, this disruption is heterogeneous throughout the tumour. Thus, relying on the disrupted BBTB for achieving effective drug concentrations in brain tumours has met with little clinical success. Because of this, it would be beneficial to design drugs and drug delivery strategies to overcome the 'normal' BBB to effectively treat the brain tumours. In this review, we discuss the role of BBB/BBTB in brain tumour diagnosis and treatment highlighting the heterogeneity of the BBTB. We also discuss various strategies to improve drug delivery across the BBB/BBTB to treat both primary and metastatic brain tumours. Recognizing that the BBB represents a critical determinant of drug efficacy in central nervous system tumours will allow a more rapid translation from basic science to clinical application. A more complete understanding of the factors, such as BBB-limited drug delivery, that have hindered progress in treating both primary and metastatic brain tumours, is necessary to develop more effective therapies.

Durable Effect of Pyrotinib and Metronomic Vinorelbine in HER2-Positive Breast Cancer With Leptomeningeal Disease: A Case Report and Literature Review

Leptomeningeal metastases (LM) are rare and catastrophic for metastatic breast cancer (MBC). The prognosis of HER2-positive breast cancer (BC) with LM is extremely poor. There is no high-quality evidence of treatment regimens in HER2-positive BC with LM yet. Here, we present a case of LM in a 50-year-old woman with HER2-positive BC. Immunohistochemistry revealed invasive ductal carcinoma, estrogen receptor negative, progesterone receptor negative, HER2 3+, P53 positive 80%, and Ki-67 positive 35%. Reported for the first time, the patient was given pyrotinib-targeted therapy (400 mg, oral, every day), metronomic vinorelbine (40 mg, oral, three times a week), and intrathecal methotrexate (10 mg, infrequent and irregular use due to poor compliance) synchronously. The patient received and benefited from the treatment regimen for 16 months. And the quality of life, as self-reported, improved significantly. We also comprehensively summarized all the case reports, observational studies, and clinical trials related to HER2-positive BC with LM in the PubMed database and ClinicalTrials.gov. Intrathecal chemotherapy (methotrexate, cytarabine, thiotepa), intrathecal trastuzumab, whole-brain radiotherapy, and systemic therapy are commonly used treatment options according to a review of the literature and research. Pembrolizumab and trastuzumab deruxtecan (DS-8201) as novel drugs are promising in LM. Furthermore, trastuzumab emtansine (T-DM1) and tyrosine kinase inhibitors (TKIs) such as tucatinib and neratinib have exhibited good efficacy in HER2-positive BC with central nervous system (CNS) metastases and deserve further exploration. In our report, combining pyrotinib-targeted therapy with metronomic chemotherapy is a potential regimen, which has presented satisfactory therapeutic efficacy and also warrants additional investigation in HER2-positive BC with LM.

Unusual case of long survival patient with leptomeningeal carcinomatosis from breast cancer

Leptomeningeal carcinomatosis (LC) is defined as infiltration of the leptomeninges by metastatic carcinoma and often represents the end stage of cancer disease. In breast cancer, LC is associated with a median survival of approximately 6-8 weeks without specific treatment. It could increase by only few months with personalized treatment plans. Usually, the median time of onset of leptomeningeal spread is 18 months and it is diagnosed in up to 70% of patients with active and progressive systemic disease. We present an uncommon case of LC in a patient with history of breast cancer with a 10 year-disease-free condition and an overall survival after LC diagnosis of 10 months. Central Nervous System (CNS) Magnetic Resonance Imaging (MRI) showed contrast enhancement of medullary cone and cauda. Despite the negativity of cytological analysis of Cerebral-Spinal Fluid (CSF), the patient underwent meningeal and radicular biopsy in November 2019. The neuropathological examination confirmed the diagnosis of LC. The patient was started on the aromatase inhibitor anastrozole. A whole body contrast Computed Tomography (CT) scan at three months follow-up was negative for further disease dissemination. The patient is currently under oncological and radiological follow-up after more than 10 months from diagnosis. Although nowadays diagnosis of LC is prompted by cytological examination of CSF, its negativity should not halt the diagnostic process. In the presence of a high clinical suspicion of LC, we suggest the biopsy of lesion.

Loco-regional drug delivery in oncology: current clinical applications and future translational opportunities

Introduction: Drug-based treatment regimens for cancer are often associated with off-target toxic side effects and low penetration of the drug at the tumor site leading to patient morbidity and limited efficacy. Loco-regional drug delivery has the potential to increase efficacy while concomitantly reducing toxicity.Areas covered: Clinical applications using loco-regional delivery include intra-arterial drug delivery in retinoblastoma, direct intra-tumoral (IT) injection of ethanol for ablation in hepatocellular carcinoma (HCC) and the use of HIPEC in peritoneal carcinomas. In recent years, there has been a significant increase in both approved products and clinical trials, with a particular emphasis on drug delivery platforms such as drug-eluting beads for HCC and hydrogel platforms for intravesical delivery in bladder cancer.Expert opinion: Development of loco-regional drug-delivery systems has been slow, limited by weak clinical data for early applications and challenges relating to dosing, delivery and retention of drugs at the site of action. However, there is increasing focus on the potential of loco-regional drug delivery when combined with bespoke drug-delivery platforms. With the growth in immunotherapies, the use of IT delivery to drive priming of the anti-tumor response has opened up a new field of opportunity for loco-regional drug delivery.

Addressing BBB Heterogeneity: A New Paradigm for Drug Delivery to Brain Tumors

Effective treatments for brain tumors remain one of the most urgent and unmet needs in modern oncology. This is due not only to the presence of the neurovascular unit/blood-brain barrier (NVU/BBB) but also to the heterogeneity of barrier alteration in the case of brain tumors, which results in what is referred to as the blood-tumor barrier (BTB). Herein, we discuss this heterogeneity, how it contributes to the failure of novel pharmaceutical treatment strategies, and why a "whole brain" approach to the treatment of brain tumors might be beneficial. We discuss various methods by which these obstacles might be overcome and assess how these strategies are progressing in the clinic. We believe that by approaching brain tumor treatment from this perspective, a new paradigm for drug delivery to brain tumors might be established.