Systemic chemotherapy, intrathecal chemotherapy, and symptom management in the treatment of leptomeningeal metastasis

Locoregional delivery of CAR-T cells in the clinic

Cellular therapies utilizing T cells expressing chimeric antigen receptors (CARs) have garnered significant interest due to their clinical success in hematological malignancies. Unfortunately, this success has not been replicated in solid tumors, with only a small fraction of patients achieving complete responses. A number of obstacles to effective CAR-T cell therapy in solid tumors have been identified including tumor antigen heterogeneity, poor T cell fitness and persistence, inefficient trafficking and inability to penetrate into the tumor, immune-related adverse events due to on-target/off-tumor toxicity, and the immunosuppressive tumor microenvironment. Many preclinical studies have focused on improvements to CAR design to try to overcome some of these hurdles. However, a growing body of work has also focused on the use of local and/or regional delivery of CAR-T cells as a means to overcome poor T cell trafficking and inefficient T cell penetration into tumors. Most trials that incorporate locoregional delivery of CAR-T cells have targeted tumors of the central nervous system - repurposing an Ommaya/Rickham reservoir for repeated delivery of cells directly to the tumor cavity or ventricles. Hepatic artery infusion is another technique used for locoregional delivery to hepatic tumors. Locoregional delivery theoretically permits increased numbers of CAR-T cells within the tumor while reducing the risk of immune-related systemic toxicity. Studies to date have been almost exclusively phase I. The growing body of evidence indicates that locoregional delivery of CAR-T cells is both safe and feasible. This review focuses specifically on the use of locoregional delivery of CAR-T cells in clinical trials.

Treatment Options in Refractory Autoimmune Encephalitis

Autoimmune encephalitis represents a potentially treatable immune-mediated condition that is being more frequently recognized. Prompt immunotherapy is a key factor for the management of autoimmune encephalitis. First-line treatments include intravenous steroids, plasma exchange, and intravenous immunoglobulins, which can be combined in most severe cases. Rituximab and cyclophosphamide are administered as second-line agents in unresponsive cases. A minority of patients may still remain refractory, thus representing a major clinical challenge. In these cases, treatment strategies are controversial, and no guidelines exist. Treatments proposed for refractory autoimmune encephalitis include (1) cytokine-based drugs (such as tocilizumab, interleukin-2/basiliximab, anakinra, and tofacitinib); (2) plasma cell-depleting agents (such as bortezomib and daratumumab); and (3) treatments targeting intrathecal immune cells or their trafficking through the blood-brain barrier (such as intrathecal methotrexate and natalizumab). The efficacy evidence of these drugs is mostly based on case reports or small case series, with few reported controlled studies or systematic reviews. The aim of the present review is to summarize the current evidence and related methodological issues in the use of these drugs for the treatment of refractory autoimmune encephalitis.

Management of hydrocephalus in patients with leptomeningeal metastases: an ethical approach to decision-making

PURPOSE

Leptomeningeal metastases (LM) are a rare, but often debilitating complication of advanced cancer that can severely impact a patient's quality-of-life. LM can result in hydrocephalus (HC) and lead to a range of neurologic sequelae, including weakness, headaches, and altered mental status. Given that patients with LM generally have quite poor prognoses, the decision of how to manage this HC remains unclear and is not only a medical, but also an ethical one.

METHODS

We first provide a brief overview of management options for hydrocephalus secondary to LM. We then apply general ethical principles to decision making in LM-associated hydrocephalus that can help guide physicians and patients.

RESULTS

Management options for LM-associated hydrocephalus include shunt placement, repeated lumbar punctures, intraventricular reservoir placement, endoscopic third ventriculostomy, or pain management alone without intervention. While these options may offer symptomatic relief in the short-term, each is also associated with risks to the patient. Moreover, data on survival and quality-of-life following intervention is sparse. We propose that the pros and cons of each option should be evaluated not only from a clinical standpoint, but also within a larger framework that incorporates ethical principles and individual patient values.

CONCLUSIONS

The decision of how to manage LM-associated hydrocephalus is complex and requires close collaboration amongst the physician, patient, and/or patient's family/friends/community leaders. Ultimately, the decision should be rooted in the patients' values and should aim to optimize a patient's quality-of-life.

Intrathecal chemotherapy as a treatment for leptomeningeal metastasis of non-small cell lung cancer: A pooled analysis

Leptomeningeal metastasis (LM) is increasingly common in patients with non-small cell lung cancer (NSCLC) due to improved treatment, and ultimately, prolonged patient survival. The current study is a pooled analysis that evaluated intrathecal chemotherapy (ITC) as a treatment for NSCLC patients with LM. The PUBMED, OVID, EBSCO and Cochrane Library databases were searched for published studies involving ITC in NSCLC patients with LM. The primary outcomes of interest included response (symptomatic, radiographic and cytological) and survival. Overall, 4 prospective studies and 5 retrospective studies were included. In total, 37 patients received ITC only, and 552 patients received multiple interventions (ITC, whole-brain radiotherapy, epidermal growth factor receptor tyrosine kinase inhibitors, systemic chemotherapy and support care). In patients with available individual information, the reevaluated cytological, clinical and radiographic rates of response to ITC were 55% (53-60%; n=49), 64% (53-79%; n=58), and 53% (n=32), respectively, and the reevaluated median survival time (from the onset of treatment, n=50) was 6.0 months (95% CI, 5.2-6.8). In patients without available individual information, the reported cytological and clinical rates of response to ITC are 14-52% and 13-50%, respectively, and the reported median survival time (from the diagnosis of LM) was 3.0-4.3 months. The clinical response rates of patients only receiving ITC varied from 71 to 79% (100% if including stable disease). The median survival time of patients who only received ITC (7.5 months) was much longer than that of patients who received multiple interventions (3.0-5.0 months). Accordingly, in NSCLC patients with LM, ITC may offer a promising response rate and survival benefits under a suitable regimen. In addition, a suitable combination strategy of multidisciplinary therapy is extremely important for these particular patients.

Role of ventriculoperitoneal shunting in patients with neoplasms of the central nervous system: An analysis of 59 cases

Approximately 1-5% of patients with cerebral metastasis and ~40% of patients with primary brain tumors suffer from hydrocephalus. These patients often exhibit a poor prognosis. The aim of the present study was to reassess the validity of ventriculoperitoneal shunting (VPS) with the assistance of the general surgeon in oncological patients. A total of 59 patients underwent first-time VPS at the Beth Israel Deaconess Medical Center (Boston, USA) between 2004 and 2012; 40 patients had hydrocephalus from brain metastasis and 19 from primary tumors. The analyzed independent variables included demographics, body mass index, past medical history, clinical presentation, indication for surgery, Karnofsky performance status (KPS) score and surgical technique; the dependent variables were postoperative symptoms and occurrence, cause and time of shunt failure. The outcomes were analyzed with the t-test and Kaplan-Meier estimates for shunt survival. The mean age of the patients was 57.2 years and the mean operative time was 50.4 min. Symptomatic palliation was achieved in 93% of the cases; patients with severe symptoms, such as debilitating headaches, nausea and vomiting, benefited significantly from VPS. The mean follow-up time was 6.3 months; complications occurred in only 7 patients (11.8%) during follow-up: 2 in the proximal shunt (1 infection and 1 obstruction), both requiring revision, 1 infection in the distal catheter requiring shunt removal, 2 cases of intracerebral bleeding that were monitored with computed tomography scans, 1 wound infection treated with antibiotics and 1 valve complication that required temporary revision. The initial and 3-month KPS scores were 65±16.4 and 75±16.0, respectively. The mean overall shunt survival was 6.4 months (range, 1.0 day-76.0 months) from the placement of the VP shunt. At 3 months after VPS, 93.5% of the patients remained alive with functioning shunts and at 1 year 87% of the shunts were still functioning. In conclusion, VPS remains a valid option for cancer patients with low KPS, as it improves the quality of life in such patients, even in the setting of previous infection, hemorrhage, or leptomeningeal disease, since shunt patency outlasts the overall survival of nearly all patients.

Plasma and cerebrospinal fluid pharmacokinetics of thalidomide and lenalidomide in nonhuman primates

PURPOSE

Thalidomide, originally developed as a sedative, was subsequently identified to have antiangiogenic properties. Lenalidomide is an antiangiogenic and immunomodulatory agent that has been utilized in the treatment of patients with brain tumors. We studied the pharmacokinetics and cerebrospinal fluid (CSF) penetration of thalidomide and lenalidomide in a nonhuman primate model.

METHODS

A dose of 50 mg of thalidomide or 20 mg of lenalidomide was administered once orally to each of three rhesus monkeys. Plasma and CSF samples were obtained at specified intervals, and the thalidomide or lenalidomide concentrations were determined by high-performance liquid chromatography with tandem mass spectrometry. Pharmacokinetic parameters were estimated using noncompartmental methods. CSF penetration was calculated as area under the concentration-time curve (AUC) CSF/AUC plasma.

RESULTS

For thalidomide, the median apparent clearance (Cl/F) was 2.9 mL/min/kg, the median plasma AUC was 80 μM h, and the median terminal half-life (t(½)) was 13.3 h. For lenalidomide, the median Cl/F was 8.7 mL/min/kg, the median AUC was 9 μM h, and the median t(½) was 5.6 h. Thalidomide was detected in the CSF of all animals, with a median penetration of 42%. Lenalidomide was detected in the CSF of 2 of 3 animals, with a CSF penetration of 11% in each.

CONCLUSION

Thalidomide and lenalidomide penetrate into the CSF after oral administration of clinically relevant doses. Plasma exposure to lenalidomide was similar in our model to that observed in studies involving children who have brain tumors. These results support further development of lenalidomide for the treatment of central nervous system malignancies.

Novel approaches to treating leptomeningeal metastases

Leptomeningeal metastasis is a devastating complication of the central nervous system in patients with late-stage solid or hematological cancers. Leptomeningeal metastasis results from the multifocal seeding of the leptomeninges by malignant cancer cells. Although central nervous system metastasis usually presents in patients with widely disseminated and progressive late-stage cancer, malignant cells may spread to the cerebrospinal fluid during earlier disease stages in particularly aggressive cancers. Treatment of leptomeningeal metastasis is largely palliative but will often provide stabilization and protection from further neurological deterioration and improve quality of life. There is a need to raise awareness of the impact of leptomeningeal metastases on cancer patients and its known and putative biological basis. Novel diagnostic approaches include identification of biomarkers that may stratify the risk for developing leptomeningeal metastasis. Current therapies can be used more effectively while waiting for advanced treatments to be developed.

Palliative ventriculoperitoneal shunt in a pediatric patient with recurrent metastatic medulloblastoma

The authors present a case report of a pediatric patient with recurrent metastatic medulloblastoma who demonstrated significant clinical improvement after placement of a palliative ventriculoperitoneal (VP) shunt. They also review the medical literature that supports palliative surgical management of hydrocephalus and intracranial hypertension (ICH) caused by leptomeningeal (LM) spread of malignancy. The burdens and benefits of an invasive surgical procedure must always be weighed carefully, especially at end-of-life. Yet for some patients with LM spread and ICH, VP shunting may improve their quality of life, although their prognosis remains poor.

Successful treatment of leptomeningeal metastases from breast cancer using the combination of trastuzumab and capecitabine: a case report

We report a case of metastatic breast cancer with leptomeninges and multiple bone metastases that showed an excellent response to the combination of trastuzumab and capecitabine; therapeutic effect was evaluated by MRI at follow-up. A 44-year-old woman underwent modified radical mastectomy in February 1997. In April 2003, a tumor at the right basis cerebri and multiple bone metastases were noted, and in October 2003, she underwent enucleation of the tumor. Histopathologically, the tumor was consistent with a basal skull metastasis from breast cancer. In March 2004, the patient began to experience pain, weakness, and paresthesia of both legs. She was diagnosed, with leptomeningeal metastasis (LM) from breast cancer using MRI. In December 2005, the combination of trastuzumab and capecitabine administered as sixth-line treatment was very effective for LM. Although it is generally very difficult to diagnose LM and assess the therapeutic effect with MRI, in this case, it was possible. To our knowledge, there has been no report in the literature describing the combination of trastuzumab and capecitabine for LM from breast cancer. Although the mechanism underlying the efficacy of this combination is still unknown, the treatment would be worth trying because of its few side effects in extensively treated patients with LM from breast cancer. To confirm the antitumor efficacy of trastuzumab and capecitabine, however, further investigations are required.

Chemotherapy in neoplastic meningitis

Neoplastic meningitis (NM) is the result of the diffuse or multifocal localization of cancer cells in the cerebral spinal fluid (CSF). NM is more often a late complication of solid tumor or lymphoproliferative malignancies. At present, the goal of therapeutic strategies is palliative and the evaluation of high or low risk is important in identifying which patients could benefit from aggressive treatments such as radiation therapy and chemotherapy. Given that NM is a cancer complication that can spread throughout the entire subarachnoid space, chemotherapy, whether intrathecal or systemic, is currently considered the best treatment option, but optimal treatment is still controversial. This review summarizes intrathecal and systemic chemotherapeutic options in the treatment of NM and the related toxicities.

Management of leptomeningeal malignancy

Leptomeningeal carcinomatosis is defined as malignant infiltration of the pia matter and arachnoid membrane. Leukaemias and lymphomas, lung, breast cancer and melanoma are the primary tumours commonly associated with leptomeningeal carcinomatosis. Diagnosis is based on compatible symptoms and signs, cytological evidence of malignancy in the cerebrospinal fluid, and neuroimaging studies. Treatment is largely palliative (median survival 2-4 months). Patients with lympomatous or leukaemic meningitis, chemosensitive tumours such as breast cancer, low tumour burden, minimal neurological deficits, good performance status and controllable systemic disease survive longer with occasional long-term responses. Available treatment options include focal radiation therapy to CNS sites of bulky, symptomatic or obstructive meningeal deposits, intrathecal cytotoxic therapy and systemic chemotherapy. No evidence of superiority of intrathecal treatment compared with best palliative care (including radiation therapy and systemic treatment) is available from clinical trials. Novel treatment approaches include intrathecal liposomal Ara-C, the development of new cytotoxic compounds, signal transduction inhibitors and monoclonal antibodies for intrathecal or systemic use. Until data from multi-centre randomised trials are available, rationalisation of therapy should be done by stratifying patients to prognostic groups. High-risk patients will only survive for a few weeks and are better managed with supportive measures, whereas low-risk patients justify vigorous cerebrospinal fluid-directed treatment combined with radiation therapy and systemic chemotherapy.

Diagnosis and management of central nervous system metastases from breast cancer

The brain, cranial nerves, leptomeninges, spinal cord, and eye compose the central nervous system (CNS) and are at risk for the development of metastases from breast cancer. Such metastases are diagnosed on the basis of clinical suspicion and substantiated by neuroimaging, resection when indicated, and sampling of cerebrospinal fluid when leptomeningeal metastasis (LM) is suspected. Treatment is aimed at palliation of symptoms and preservation of neurologic function. Historically, conventional radiation therapy has been the mainstay of palliative treatment for brain, cranial nerve, spinal cord, and ocular metastases. However, additional treatment options for brain metastases have been brought about by technological advances in surgery to resect brain metastases, and stereotactic radiosurgery (SRS) to focally irradiate metastases, both of which have been substantiated by data from randomized trials. Ongoing research is aimed at refining criteria to select which patients with brain metastases should undergo surgery and SRS and how these focal therapies should be optimally integrated with whole-brain radiotherapy. Therapy for LM must carefully balance the potential risks and perceived benefits associated with CNS-directed therapies. Despite advances in neuroimaging, surgery, and radiation therapy, novel treatments are needed to improve the effectiveness of treatments for CNS metastases, especially LM, while reducing attendant neurotoxicity.