Neoplastic meningitis from solid tumors: new diagnostic and therapeutic approaches.

Neoplastic meningitis is a result of the spread of malignant cells to the leptomeninges and subarachnoid space and their dissemination within the cerebrospinal fluid. This event occurs in 4%-15% of all patients with solid tumors and represents an important prognostic factor for poor survival. Neoplastic meningitis should be diagnosed in the early stages of disease to prevent important neurological deficits and to provide the most appropriate treatment. Despite new diagnostic approaches developed in recent years, such as positron emission tomography-computed tomography and new biological markers, the combination of magnetic resonance imaging without and with gadolinium enhancement and cytology still has the greatest diagnostic sensitivity. Recently, no new randomized studies comparing intrathecal (i.t.) with systemic treatment have been performed, yet there have been a few small phase II studies and case reports about new molecularly targeted substances whose successful i.t. or systemic application has been reported. Trastuzumab, gefitinib, and sorafenib are examples of possible future treatments for neoplastic meningitis, in order to better individualize therapy thus allowing better outcomes. In this review, we analyze the most recent and interesting developments on diagnostic and therapeutic approaches.

Diagnosis and individualized therapy of neoplastic meningitis.

Neoplastic meningitis is a diffuse dissemination of tumor cells into the cerebrospinal fluid (CSF) and/or leptomeninges. It occurs in approximately 5-10% of malignant diseases, most often in breast cancer, lung cancer, melanoma or B-cell lymphoma. Symptoms of neoplastic meningitis are head or back pain, cranial nerve palsies, diffuse radicular symptoms or psychiatric disturbances. MRI shows nodular contrast enhancement lining CSF spaces. Positive CSF cytology requires optimal sampling and processing. Treatment must be individually shaped: the CSF dissemination may be treated with intrathecal chemotherapy with methotrexate or cytarabinoside (Ara-C). Liposomal Ara-C is distributed over the entire CSF space even after lumbar application and maintains cytotoxic levels for at least 2 weeks. Radiotherapy should be applied only to symptomatic solid spinal manifestations or fast progressing cranial nerve palsies. Systemic chemotherapy is needed to control solid manifestations or, in the case of substances entering the CSF, to support intrathecal chemotherapy.

[Gefitinib treatment for carcinomatous meningitis in non-small cell lung cancer]. / Géfitinib et méningite carcinomateuse d'un carcinome bronchique non à petites cellules (CBNPC).

BACKGROUND: Carcinomatous meningitis is a major complication in Non Small Cell Lung Cancer (NSCLC). Despite treatment with radiotherapy alone or in combination with intrathecal and systemic chemotherapy, its prognosis remains poor. OBSERVATION: We report a case of a female non-smoker with adenocarcinoma with bronchoalveolar features presenting with carcinomatous meningitis three years after the diagnosis of her primary tumour. Gefitinib treatment was proposed because of the persistence of meningitic symptoms despite cranial irradiation. Clinical response was observed within 3 weeks and lasted for 9 months. CONCLUSION: Gefitinib may be effective in treating carcinomatous meningitis complicating NSCLC and should be considered in this situation given the absence of effective alternatives.

Neoplastic meningitis from systemic malignancies: diagnosis, prognosis and treatment.

Long-term survival is occasionally observed in patients with neoplastic meningitis (NM) accompanying breast cancer (13% one-year and 6% 2-year survival), melanoma, and lymphoma, but in general the survival of most patients is short and averages only 3 to 4 months. The incidence of NM appears to be increasing, in part due to earlier detection by magnetic resonance imaging (MRI), and in part due to development of more effective therapies for systemic cancer, which has resulted in a larger subset at risk for late-stage development of this complication. Survival of NM patients is negatively affected by concomitant progression of systemic disease despite multiple prior therapies. However, there are certain prognostic factors that have been identified as "favorable" in retrospective series, including age less than 60 years, long symptom duration, controlled systemic disease, Karnofsky performance status (KPS) > or =70, lack of encephalopathy or cranial nerve deficits, low initial cerebrospinal fluid (CSF) protein level, history of breast primary tumor, and lack of evidence of CSF compartmentalization or bulky meningeal disease as determined by CSF flow studies. Standard treatment has traditionally involved radiotherapy (RT) to sites of symptomatic or bulky disease, as detected by neuroimaging, and in selected patients, the administration of intrathecal, intraventricular, or systemic chemotherapy. However, treatment remains palliative and many patients and physicians choose supportive care only. Future hope is provided by studies that have improved our understanding of the disease pathogenesis, have identified prognostic variables associated with outcome, and have provided new therapeutic approaches, such as administration of high-dose systemic chemotherapy and investigations of novel therapeutic agents.

Neoplastic meningitis.

Neoplastic meningitis is a complication of the CNS that occurs in 3-5% of patients with cancer and is characterised by multifocal neurological signs and symptoms. Diagnosis is problematic because the disease is commonly the result of pleomorphic manifestations of neoplastic meningitis and co-occurrence of disease at other sites. Useful tests to establish diagnosis and guide treatment include MRI of the brain and spine, cerebrospinal fluid (CSF) cytology, and radioisotope CSF flow studies. Assessment of the extent of disease of the CNS is of value because large-volume subarachnoid disease or CSF flow obstruction is prognostically significant. Radiotherapy is an established and beneficial treatment for patients with neoplastic meningitis with large tumour volume including parenchymal brain metastasis, sites of symptomatic disease, or CSF flow block. Because neoplastic meningitis affects the entire neuraxis, chemotherapy treatment can include intra-CSF fluid (either intraventricular or intralumbar) or systemic therapy. Most patients (>70%) with neoplastic meningitis have progressive systemic disease and consequently treatment is palliative and tumour response is of restricted durability. Furthermore, as there is no compelling evidence of a survival advantage with aggressive multimodal treatment, future trials need be done to determine the effect of treatment on quality of life and control of neurological symptoms.

Refractory headache in a patient with breast cancer and carcinomatous meningitis unresponsive to analgesics: case report.

A 44-year old female presented with locally advanced breast cancer that had been treated with neoadjuvant chemotherapy followed by modified radical mastectomy and thereafter three cycles of paclitaxel. She presented with severe refractory headache that was unresponsive to oral analgesics including morphine. Both CT and MRI scans with contrast were normal, however her cerebrospinal fluid was positive for malignant cells. The patient's headache responded to whole brain radiotherapy.

The treatment of neoplastic meningitis.

Neoplastic meningitis (NM) is a debilitating complication of cancer that occurs when tumour cells infiltrate the leptomeninges. Treatment often includes direct installation of chemotherapy into the cerebrospinal fluid either by lumbar puncture or the use of a ventricular reservoir, radiation therapy, systemic chemotherapy or a combination of these modalities. The current standard chemotherapeutic agents for direct instillation into the cerebrospinal fluid include methotrexate, cytarabine and thiotepa. Other agents, such as topotecan, manfosfamide and IFNs, are undergoing evaluation in clinical trials. Despite active investigation of new therapies, the prognosis for patients with NM remains poor. However, some patients do demonstrate improvement of neurological function and prolongation of survival with treatment. Therefore, careful evaluation and treatment planning is warranted in order to avoid treatment-associated toxicities and to maximise the impact of the treatment on the disease process.

Standard and novel radiotherapeutic approaches to neoplastic meningitis.

Neoplastic meningitis usually occurs late in the natural history of cancer. Adequate staging and assessment of the patient's overall reserves and prognosis are crucial in determining whether aggressive treatment is justified. Although radiotherapy remains the single most effective treatment, it is considered palliative for epithelial cancers and is generally directed to sites of bulky disease that obstruct the flow of cerebrospinal fluid or cause neurologic dysfunction. Such diseases as leukemia, medulloblastoma, and germinoma are exceptions that can be treated definitively with craniospinal irradiation. Innovations in conformal therapy may help to reduce the significant amount of myelosuppression associated with spinal irradiation. The main long-term toxicity associated with whole-brain irradiation (WBI) is dementia resulting from leukoencephalopathy, which may be exacerbated when WBI is given in combination with chemotherapy. A case report highlighting the use of radiotherapy for palliation in a patient with neoplastic meningitis is presented at the end of this article.

Carcinomatous meningitis as a clinical manifestation of pancreatic carcinoma.

Carcinomatous meningitis (CM) is clinically less common than brain metastasis or spinal cord compression, having dire consequences for both the quality of life and the overall survival of patients with solid tumors. It occurs in about 5% of all adult cancer patients, but autopsies may double this number. If leukemia and lymphoma are excluded, most cases are due to breast cancer, lung cancer and melanoma. In this report, we describe a 49-year-old male patient with metastatic pancreatic adenocarcinoma who developed carcinomatous meningitis. To our knowledge, this is only the second case of carcinomatous meningitis secondary to a pancreatic carcinoma described so far.

In vivo therapy of neoplastic meningitis with methotrexate and 5.

We examined whether the administration of methotrexate (MTX) prior to the injection of 5-[125I]iodo-2'-deoxyuridine (125IUdR) in rats with intrathecal (i.t.) TE-671 human rhabdomyosarcoma would enhance 125IUdR uptake by tumor cells and augment the therapeutic efficacy of this Auger-electron-emitting radiopharmaceutical. TE-671 cells were exposed in vitro to medium +/- MTX, and the percentage of cells in various phases of the cell cycle and the uptake of 125IUdR assessed. In addition, nude rats were injected i.t. with TE-671 cells and later infused i.t. with saline or MTX for 24 h prior to 125IUdR injection, and the radioactivity associated with their spinal cords was determined. Exposure of tumor cells in vitro to MTX leads to an increase in the uptake of 125IUdR as a consequence of both a rise in the absolute uptake per cell and an increase in the percentage of S-phase cells. A corresponding increase of radioactivity within the spinal cords of tumor-bearing rats also occurs in the presence of MTX. Tumor-bearing animals were infused/injected with MTX and/or 125IUdR, and the onset of paralysis was determined as a function of time. We find that: (i) MTX infusion leads to a slight increase in time to onset of paralysis (median [M] = 24 vs. 22 days, p = 0.79); (ii) 125IUdR injection results in a statistically significant delay (p < 0.01) in the onset of paralysis (M= 39 days); (iii) MTX administration prior to 122IUdR injection further increases the therapeutic efficacy (M = 45 days).

Radioimmunotherapy with alpha-particle emitting radioimmunoconjugates.

Radionuclides which decay by the emission of alpha-particles are attractive for certain radioimmunotherapeutic applications. These include the treatment of lymphomas, compartmentally spread malignancies such as ovarian cancer and neoplastic meningitis, and micrometastatic disease. Two alpha-emitting radionuclides of interest for this purpose are 212Bi (60.6 min half life) and 211At (7.2 hr half life). Compared with the beta-emitters commonly used for radiotherapy, the alpha-particles of 212Bi and 211At are of higher energy, much shorter range (less than 100 microm), and considerably higher linear energy transfer. Preliminary results obtained in a variety of in vitro systems and in vivo models have documented the exquisite toxicity of alpha-particles and have established a basis for initiating radiotherapy trials in humans with monoclonal antibodies labeled with alpha-emitting radionuclides.

Radioimmunotherapy of neoplastic meningitis in rats using an alpha-particle-emitting immunoconjugate.

Because of their short range and high linear energy transfer, alpha-particles may be particularly effective in the treatment of neoplastic meningitis. Monoclonal antibody 81C6 was labeled with alpha-particle-emitting 211At using N-succinimidyl3-[211At]astatobenzoate, and the efficacy and toxicity of this immunoconjugate were evaluated in an athymic rat model. Animals were given injections via a chronic indwelling catheter with 5 x 10(5) TE-671 human rhabdomyosarcoma cells and treated 8 days later with single intrathecal doses of either saline or 4-18 microCi of 211At-labeled specific 81C6 antibody or isotype-matched control 211At-labeled 45.6 antibody. In the first experiment, 4, 7, and 13 microCi 211At-labeled 81C6 produced statistically significant (P = 0.004-0.02) increases in median survival of 33, 29, and 51%, respectively, as compared with saline. Two of 10 animals receiving the 13-microCi dose lived for 6 months before being killed for histological analysis. In the second experiment, 12 microCi of 211At-labeled 45.6 did not increase median survival significantly relative to saline control, while 12 microCi of 211At-labeled 81C6 increased median survival by 113% (P < 0.005) and resulted in 33% apparent cures. Five of 10 animals receiving 18 microCi of 211At-labeled 81C6 survived until they were killed at 295 days. An additional study was performed in animals given intrathecal injections of 5 x 10(6) TE-671 cells and given a single dose of 18 microCi of 211At-labeled 81C6 or 211At-labeled 45.6. At this higher cell number, significantly prolonged survival was still seen for specific antibody as compared with saline (P < 0.001) and control antibody (P < 0.05). These results suggest that treatment with 211At-labeled monoclonal antibodies may be a valuable approach for neoplastic meningitis.

Involved-field radiotherapy and intra-Ommaya methotrexate/cytarabine in patients with AIDS-related lymphomatous meningitis.

PURPOSE: To evaluate combined limited-field radiotherapy and concentration times time (C X T) intra-CSF chemotherapy in patients with AIDS-related lymphomatous meningitis (LM). PATIENTS AND METHODS: Fourteen men and one woman with AIDS had cytologically documented LM. Eleven patients had systemic non-Hodgkin's lymphoma (NHL) (all B-cell histology, including six immunoblastic, four large cell, one small cell) with leptomeningeal metastases and four patients had primary CNS lymphoma (PCNSL) (all B-cell histology, including two immunoblastic, two large cell) with CSF dissemination. Presenting neurologic examinations included cranial neuropathies (n = 7), normal (n = 4), abulia (n = 2), paraparesis (n = 2), ataxia (n = 1), hemiparesis (n = 1), and aphasia (n = 1). Standardized pretreatment evaluations included contrast cranial magnetic resonance/computed tomography (MR/CT), placement of an intraventricular reservoir, CT myelogram/contrast spine MR, ophthalmologic examination, and indium 111-pentetic acid (DTPA) CSF flow studies. Regions of bulky or symptomatic disease were treated with limited-field radiation therapy, which included whole brain in 10 patients combined with spinal cord irradiation in five patients. Concurrent systemic chemotherapy was administered in 12 patients. All patients were scheduled to receive intraventricular methotrexate (MTX) 2 mg/d for 5 consecutive days biweekly for 8 weeks (induction), followed in cytologically responding patients by MTX administered in a similar manner every 4 weeks (maintenance). In MTX-responsive and consenting patients with cytologic relapse, intraventricular cytarabine (ara-C) was administered, 25 mg/d for 3 consecutive days weekly for 4 weeks (induction), followed by ara-C administered in a similar manner every 4 weeks (maintenance). CSF cytology and neurologic examinations were performed biweekly. RESULTS: In 13 assessable patients (two patients refused CNS directed therapy following standardized pretreatment evaluations), median time to tumor progression was 60 days (range, 3 to 260) and median survival duration was 125 days (range, 44 to 260). Response rate, determined clinically (four of 13 patients) and cytologically (nine of 13), was 69%. Complications included reservoir infection (n = 2) and myelosuppression (n = 11); the latter was felt to be a consequence of coadministered systemic chemotherapy. CONCLUSION: There were no treatment-related deaths. We conclude that involved-field irradiation and intraventricular MTX/ara-C is effective palliative treatment of AIDS-related LM.

Immunoreactivity, pharmacokinetics and bone marrow dosimetry of intrathecal radioimmunoconjugates.

Ten patients with neoplastic meningitis were treated with a variety of 131I-monoclonal antibody (MAb) conjugates, chosen to bind to their particular malignancy. Pharmacokinetic studies revealed that MAbs leave the ventricular compartment, enter the sub-arachnoid space and then pass into the blood. Once the MAbs enter the blood compartment, their clearance is determined by factors such as circulating anti-mouse Ig and circulating antigens. These lead to complex formations and the clearance of the conjugate by the reticuloendothelial system. In one individual, the anti-mouse Ig response observed systemically was not mirrored within the CSF, which has implications for planning future therapy of this type. In other patients, formation of immune complexes was due to binding to circulating antigen within the blood. The major toxicity associated with the intrathecal administration of 131I-MAbs was bone-marrow suppression. The doses to the bone marrow, resulting from the form of therapy, were calculated but showed no direct correlation with WHO grade 3/4 toxicity. Doses to the ventricular lining were also calculated, but due to the complex geometry of the compartment, calculation of potential tumour doses was not practicable.

Carcinomatous meningitis: antibody-guided therapy with I-131 HMFG1.

Seven patients with carcinomatous meningitis were administered intrathecal I-131 labelled monoclonal antibody HMFG1. Clinical responses were seen in two patients, with a long term survivor at 32 months. Aseptic meningitis occurred in 4/7 patients, but more serious toxicity was observed in the form of seizures (2/7 patients) and myelosuppression (3/7 patients). Partial obliteration of the subarachnoid space was identified as a potential problem in patients with advanced disease.