eMedicine Specialties > Radiology > Brain/Spine

Leptomeningeal Carcinomatosis

Andrew L Wagner, MD, Assistant Professor of Radiology, Instructional Faculty, University of Virginia School of Medicine; Director of Neuroradiology, Department of Radiology, Rockingham Memorial Hospital

Updated: Feb 1, 2007

Introduction

Background

Leptomeningeal carcinomatosis (LC) refers to diffuse seeding of the leptomeninges by tumor metastases and was first reported in 1870 by Eberth, although the term was not used until the early 20th century. This type of spread occurs in an estimated 20% of patients diagnosed with cancer and is most commonly found in breast carcinoma, lung carcinoma, and melanoma in adults and hematogenous malignancies and primitive neuroectodermal tumor (PNET) in children. While less commonly seen in practice, prostate cancer can spread to the leptomeninges and is a grim finding in this often treatable neoplasm. The antemortem diagnosis is becoming more common, as newer therapies increase the life span of cancer patients and improvements in technology increase the sensitivity of imaging studies.

Patients typically present with symptoms caused by the effects of tumor emboli on subarachnoid nerve roots, direct invasion into the spinal cord or brain, or cerebrospinal fluid (CSF) obstruction. MR and CT demonstrate multiple masses within the subarachnoid space, hydrocephalus without a discernible cause, or diffuse leptomeningeal enhancement. The latter enhancement pattern has been referred to as cake icing or zuckerguss (German for sugar icing) and can be found in the brain, spine, or both (see Images 1-2).

Early diagnosis is important to begin therapy prior to neurologic deterioration. While there are clinical signs and radiologic findings that strongly suggest LC, most cases typically are diagnosed by CSF cytology or leptomeningeal biopsy. As the diagnostic accuracy of a single lumbar puncture (LP) is only 50-60% and 90% after 3 LPs, MR is considered complementary and can be invaluable, detecting up to 50% of cases with false-negative LPs.

Without appropriate therapy, the outlook is grim, and untreated patients are unlikely to survive more than 4-6 weeks. Intrathecal chemotherapy and/or radiation can increase survival to some extent, but most patients succumb to their disease within 6-8 months. Survival depends to some extent on the cell type of tumor involved, but the eventual outcome is invariably the same.

For excellent patient education resources, visit eMedicine's Cancer and Tumors Center. Also, see eMedicine's patient education article Brain Cancer.

Pathophysiology

Primary tumors can spread to the leptomeninges in a variety of ways. Direct extension may occur from an intraparenchymal or periventricular primary brain tumor that forms in tissue near the CSF, and this is commonly found in medulloblastomas and other PNETs, ependymoma, and occasionally in glioblastoma multiforme. Arterial metastases can invade the CSF by pial rupture, ependymal invasion, or by extension along Virchow-Robin spaces.

Tumors also can extend in a perineural fashion along cranial nerves to eventually enter the subarachnoid space, and this pathway is particularly associated with squamous cell tumors of the head and neck. A similar method of spread along perineural spaces of the spinal nerves can occur with vertebral body or lymph node metastases.

Venous hematogenous access to the subarachnoid space can occur by a number of pathways, such as Batson plexus (internal vertebral venous plexus), the choroid plexus, or through the vessels of the arachnoid. Leukemia classically spreads hematogenously and has been shown to gain access to the CSF by invading the walls of arachnoid veins as well as through microinfarcts that break down the blood-brain barrier.

A less common route for CSF metastases is iatrogenic spread of tumor, which is becoming more frequent now that resection of solitary brain metastases has been shown to be beneficial to patients.

The choroid plexus forms approximately 500 mL of CSF per day, which circulates throughout the subarachnoid space surrounding the brain and spinal cord before being resorbed at the arachnoid granulations and superior sagittal sinus. CSF motion is caused by pulsations of the brain and spinal cord caused by the large amount of blood flowing through these tissues with each heartbeat, the constant formation and resorption of CSF, gravity, and the patient's body movements.

Tumor cells that enter the CSF flow freely throughout the subarachnoid space, often lodging a significant distance away from their entry point. Once the tumor cells have gained access to the subarachnoid space, they spread to other portions of the meningeal surface by direct extension or by shedding cells that are then carried to different parts of the neuraxis by CSF flow.

The pattern of growth of leptomeningeal tumor consists of either (1) a sheetlike extension along the pial surface from direct extension (see Image 3), occasionally with a secondary inflammatory reaction, or (2) as multiple nodules of various sizes studding the surface of the brain, spinal cord, and nerve roots (see Images 4-5). The latter appearance typically is seen within the cerebellar folia and the cerebral sulci and easily can be mistaken as intraparenchymal metastases on MR and CT if the association of the tumors with the deep sulci of the brain is not recognized.

Tumor foci may occur throughout the spine or brain surface, as well as within the ventricular system, but demonstrate a predisposition to forming larger tumor masses and thicker leptomeningeal coating in regions of relative CSF stasis, such as the basal cisterns and cerebellopontine angles of the brain and the cauda equina in the spine (see Images 1-2).

When the tumor mass in the basal cisterns grows large enough, obstructive hydrocephalus occurs. Nonobstructive hydrocephalus also is common in LC secondary to obstruction of CSF resorption at the arachnoid granulations by tumor cells, hemorrhage, and debris.

As the leptomeninges also cover the cranial nerves, tumor seeding of the cranial nerves is not uncommon and can be seen extending into the orbit and Meckel cave. These cranial nerve metastases frequently cause symptoms either from encasement of the nerve or by direct invasion with subsequent axonal destruction and demyelination.

A nodular appearance often is seen when LC involves the spinal nerves, with tumor foci appearing as a string of beads throughout the cauda equina and extending out of the nerves into the neural foramina (see Images 3-4). Extension along the spinal nerves or the paravertebral venous plexus into the subarachnoid space can occur from vertebral or lymph node metastases as well as direct extension from adjacent primary tumors, such as lung carcinoma. Along the spinal cord, leptomeningeal tumor typically presents as a thin coating along the pia mater, although nodularity and diffuse involvement of the arachnoid space also can occur.

Frequency

United States

Leptomeningeal carcinomatosis is found in 2-25% of patients with cancer, although in 2-4%, the primary tumor is never identified. A number of studies have estimated that LC occurs in breast cancer in 5-34%, small cell lung cancer in 9-26%, and melanoma in 17-25% of patients. Because of the prevalence of breast and lung cancers, most incidences of LC occur in patients with these tumor types.

Mortality/Morbidity

Mean survival time following diagnosis is 4 weeks without treatment and 6 months with appropriate therapy. Controversy exists in the medical literature regarding the appropriate therapy for patients with LC. Radiation of affected parts is standard therapy at most institutions, with or without intrathecal (direct infusion into the CSF) and/or systemic chemotherapy. Most studies report longer survival times in patients treated with intrathecal chemotherapy, although a recent study by Bokstein et al reported no improved survival and increased complication rates in patients treated with intrathecal and systemic chemotherapy compared to systemic chemotherapy alone. Intrathecal chemotherapy is perhaps the most common form of treatment and extends the life span of select patients, but currently is limited to methotrexate, Ara-C, and thiotepa, outside of experimental work.

Race

No race predilection is recognized.

Sex

LC is found more often in women, as breast cancer is one of the more common tumors to spread in this fashion. One small study found 36 of 41 cases of LC were female, although the results were skewed because of the relative absence of melanoma in the area. While females may represent a higher percentage of patients with LC, they also live longer following diagnosis.

Age

The average age at diagnosis is reported as 48.5 years, which is relatively young because of the prevalence of women with breast cancer and pediatric cases. A bimodal peak of sorts is seen, as tumors such as leukemia and medulloblastoma account for many LC cases in children, while breast, lung, and melanoma occur at a much later age. Because of the diverse nature of the tumors, an average age of presentation that is clinically useful does not exist.

Anatomy

Leptomeninges are formed from the pia mater and arachnoid mater and enclose the subarachnoid space. The pia mater is a thin membrane that covers the surface of the brain and spinal cord and extends into the sulci and around the proximal spinal and cranial nerves. The arachnoid mater forms the outer boundary of the subarachnoid space and is composed of a thin, vascular membrane connected to the pia mater by the arachnoid trabecula. The leptomeninges extend out of the cranial nerves to a certain extent, allowing easy access to these nerves by tumor cells within the CSF.

CSF is formed at the choroid plexus of the lateral, third, and fourth ventricles and is replaced approximately 5 times a day by resorption through the arachnoid granulations and superior sagittal sinus. CSF acts as a shock absorber for the brain, transports hormones, and carries waste materials to be absorbed into the blood stream for eventual excretion. Because of its continual motion, CSF is ideally suited as a mechanism for diffuse tumor seeding within the subarachnoid space.

Presentation

The initial presentation of patients with LC can vary, but more than one half of patients have the simultaneous appearance of symptoms and signs at more than one level of the neuraxis. Although the patient initially may complain of a single symptom, careful clinical examination usually reveals numerous distinct neurologic abnormalities. Wasserstrom described a series of 90 patients with LC of which only 17 had a single neurologic deficit upon examination. Multiple level cranial nerve and spinal nerve palsies are seen commonly and are the result of direct tumor involvement, but LC should be considered even in the presence of a single cranial nerve deficit.

Headache is the most common symptom at presentation, affecting approximately 50% of patients, while pain, nausea and/or vomiting, weakness, and sensory disturbances are each seen in approximately one third. Seizures occur in approximately 20% of patients, and strokelike syndromes and diffuse encephalopathy occasionally are seen. Frequent clinical signs include altered mental status in approximately 25%, cauda equina syndrome in 20%, and polyradiculopathy in 15%.

Preferred Examination

Contrast-enhanced MR of the brain and spine is the imaging modality of choice because of its safety, excellent contrast resolution, and multiplanar abilities. A wide range of the sensitivity of MR in detecting LC has been reported. Some of this discrepancy is from the difference in sensitivity between solid tumors and hematologic malignancies, with one study reporting a sensitivity of 90% in patients with solid tumors but only 55% in patients with lymphoma and leukemia.

Recent studies have tended to show higher sensitivity rates due to advancements in MR technology, particularly better T1-weighted images as well as the advent of 3-dimensional T1-weighted sequences and postcontrast fluid attenuated inversion recovery (FLAIR). Collie et al recently reported a 100% sensitivity for intracranial LC in 25 patients evaluated with gadolinium-enhanced MR. No large recent study has looked at MR sensitivity, although it likely is in the 70-90% range in detecting intracranial LC.

When the patient has a contraindication to MR, CT myelography is the next best test to evaluate the spine and has the added benefit of allowing CSF sampling at the same time as the diagnostic test is performed. The physician must exclude obstructive hydrocephalus prior to beginning the procedure, as removal of CSF below the obstruction may result in downward herniation and death.

Plain myelography demonstrates the thickened nerve roots, subarachnoid masses, and blockage of the subarachnoid space, but has not been used as a primary diagnostic tool since the increased availability of good quality CT and MR. Plain myelography is still used to provide additional imaging during a CT myelogram.

It is important to remember that CSF cytology will detect some cases that are not visible on MR, and vice versa. Both tests should be performed if LC is clinically suspected and the initial test is negative.

Limitations of Techniques

CT continues to be used as a screening tool in the metastatic workup of many cancer patients but is relatively insensitive compared to MR, particularly in the detection of LC. Contrast-enhanced CT may miss tumor in up to one third of cases and mischaracterize leptomeningeal tumor deposits as intraparenchymal in another third. CT may be necessary when a contraindication to MR exists, such as a pacemaker or certain aneurysm clips, or when the patient is unable to hold still long enough for an MR. With the advent of newer and faster techniques and MR scanners as well as MR-compatible aneurysm clips, these situations have become less frequent.

MR depicts leptomeningeal tumor well, particularly when magnetization transfer or postcontrast FLAIR techniques are used. MR is much better at depicting metastases from solid tumors than those from hematologic malignancies.

Myelography and CT myelography have been used to evaluate LC and have the advantage of allowing CSF sampling at the time of the study. However, the test is invasive, has the risk of contrast reaction and downward herniation in patients with CSF obstruction, and has not been shown to be as sensitive as MR in detecting focal tumor deposits on the cord or nerve roots, although it is more accurate in identifying cord enlargement.

Differential Diagnoses

Meningitis, Bacterial
Tuberculosis, CNS

Other Problems to Be Considered

Meningitis, Fungal

Neurosarcoid (can easily mimic LC, as it may appear as basal cistern enhancement or multiple enhancing masses throughout the leptomeninges)

Postsurgical changes (often can lead to leptomeningeal and dural enhancement)

Computed Tomography

Findings

Contrast-enhanced CT (CECT) scans of the brain in LC are not sensitive in depicting the disease, with a false-negative rate of more than 50%. Common findings include noncommunicating hydrocephalus, intraparenchymal volume loss, and various patterns of meningeal enhancement (see Image 6). This enhancement can appear as multiple nodules, diffuse leptomeningeal enhancement, ependymal or subependymal enhancement, dural enhancement, or a combination. In the nodular form, pial enhancement is difficult to distinguish from intraparenchymal enhancement, although recognizing that the nodules follow the course of sulci assists in the diagnosis.

Cranial nerve enhancement is poorly visualized on CECT because of the proximity to osseous structures. Dural enhancement often is missed for the same reason.

In the spine, CECT also has low sensitivity, although CT myelography is approximately equal in sensitivity to MR in the detection of nerve root thickening and nodularity. The nerve roots appear thickened and beaded, and this is best visualized in the cauda equina. Tumor deposits along the surface of the cord lend the cord an irregular border, and the cord may be thickened. In extreme cases, the entire spinal canal can be filled with tumor, causing a complete CSF block.

Degree of Confidence

As described previously, both CECT and CT myelography compare unfavorably with newer MR imaging and have high false-negative rates. CECT in particular also suffers from poor specificity, as there are other disease processes that cause leptomeningeal enhancement. In the current workup of LC, limit these tests to those patients who cannot undergo an MR examination.

False Positives/Negatives

False-negative CECT scans occur in more than 50% of patients with LC. In some of these, the disease is not detectable on any imaging study, but in others, the limitations of CT imaging result in a missed diagnosis. Potential errors include lower contrast resolution than MR, adjacent dense osseous structures, and beam-hardening artifact, particularly in the posterior fossa.

False positives can be caused by benign meningeal enhancement, such as in patients with dural enhancement following LP or postsurgery and in those with intracranial hypotension. Diffuse benign parenchymal loss can mimic the volume loss and hydrocephalus associated with LC.

Magnetic Resonance Imaging

Findings

• A protocol for evaluation of intracranial leptomeningeal tumor should include postcontrast T1-weighted images in more than one plane. The coronal plane is helpful in the detection of disease over the convexities and in the cerebellum. Thin-section sequences such as magnetization prepared-rapid acquisition gradient echo (MP-RAGE) or spoiled gradient-recalled acquisition in a steady state (SPGR) following contrast are of use when evaluating the cranial nerves, as are precontrast, high-resolution, bright-CSF sequences such as constructive interference in a steady state (CISS). Recently, postcontrast fast FLAIR images have been reported to be even more sensitive to leptomeningeal enhancement than postcontrast T1 sequences (see Images 7-8). However, noncontrast FLAIR, which was thought to be a good imaging sequence for LC, is less sensitive than T1 contrast-enhanced images.
• Leptomeningeal tumor has a spectrum of appearances on MR ranging from diffuse leptomeningeal enhancement to bulky extra-axial tumor foci. The most common appearance is diffuse nonnodular enhancement of the basilar cisterns and/or supratentorial cortex, although this MR appearance is not specific for LC. Hydrocephalus without discernible enhancement also is commonly seen, but the appearance is nonspecific.
• Multiple enhancing leptomeningeal nodules also can be visualized in patients with LC, typically demonstrating larger tumor deposits in the basilar cisterns than in the supratentorial sulci. These nodules may form large clumps of tumor that cause mass effect on the adjacent brain. Even small amounts of tumor may result in obstructive hydrocephalus if they are located in narrow portions of the ventricular system, such as the fourth ventricle and aqueduct of Sylvius. When the tumor deposits are located in the supratentorial sulci, it may be difficult to distinguish them from intraparenchymal metastases, although recognizing that the enhancing nodules follow the course of the deep sulci suggests the correct diagnosis of leptomeningeal disease. Another pattern that has been described as mimicking intraparenchymal spread is nodules within the Virchow-Robin (perivascular) spaces.
• Cranial nerves often are involved clinically in LC, although many of these cases are radiologically occult. High-resolution contrast-enhanced techniques with fat saturation aid in the detection of cranial nerve tumor deposits, but pay close attention to the nerves in many cases to detect the subtle abnormalities. Although multiplanar imaging increases the sensitivity of detecting LC, coronal images best demonstrate the cranial nerves in most patients. Involved cranial nerves may have mild peripheral enhancement, which may be easily missed, as the only MR abnormality. When there is more gross involvement, nerves may be enlarged and irregular, with nodular enhancement, making detection easier. However, without a high index of suspicion, many cases can be missed easily because of the small size of the nerves and their course through the skull base.
• Spinal cord involvement mimics that of the brain stem, with peripheral linear or nodular enhancement of the pia mater. In addition, enhancement of the nerve roots within the cauda equina is often seen, ranging from tiny nodules to large masses. When spinal leptomeningeal disease is caused by direct extension from vertebral body metastases, fat-saturated enhanced T1-weighted images can be used to optimally demonstrate the vertebral body and epidural enhancement.

Gadolinium-based contrast agents (gadopentetate dimeglumine [Magnevist], gadobenate dimeglumine [MultiHance], gadodiamide [Omniscan], gadoversetamide [OptiMARK], gadoteridol [ProHance]) have been linked to the development of nephrogenic systemic fibrosis (NSF) or nephrogenic fibrosing dermopathy (NFD). For more information, see the eMedicine topic Nephrogenic Fibrosing Dermopathy. 

NSF/NFD has occurred in patients with moderate to end-stage renal disease after being given a gadolinium-based contrast agent to enhance MRI or MRA scans. NSF/NFD is a debilitating and sometimes fatal disease. Characteristics include red or dark patches on the skin; burning, itching, swelling, hardening, and tightening of the skin; yellow spots on the whites of the eyes; joint stiffness with trouble moving or straightening the arms, hands, legs, or feet; pain deep in the hip bones or ribs; and muscle weakness. For more information, see the FDA Public Health Advisory or Medscape.

Degree of Confidence

Although MR is the most sensitive and specific imaging study to evaluate for the presence of leptomeningeal tumor, there are cases where the MR may be negative in the presence of LC diagnosed by lumbar puncture, and a negative MR does not exclude the presence of disease. Gomori et al reported a 12% incidence of positive CSF cytology when in the presence of a negative MR spine examination but also found that MR was positive in 60% of patients with LC with negative CSF cytology. This suggests that the two techniques are complimentary and should not be performed if the initial test is negative.

MR findings in LC are nonspecific, as bacterial or fungal meningitis, leptomeningeal sarcoidosis, recent surgery, and even, on occasion, cerebral infarction may have a similar appearance. The estimated sensitivity of MR in the detection of LC is 34-71%, although this includes all tumor types. Separating LC into two subtypes, Freilich et al found MR abnormalities in 90% of LC from solid tumors and in 55% of patients with hematologic malignancies as the tumor of origin. Another study found even lower sensitivity of MR in hematologic LC, reporting only 6% sensitivity, although this was performed on earlier MR machines.

Another application of MR is evaluation of the presence or absence of CSF flow obstruction. MR flow studies using cardiac-gated phase contrast techniques can be used to display and quantitate cerebrospinal flow in the head and spine, and to evaluate CSF flow obstruction. In addition, spinal cord motion also may be observed to evaluate tethering or compression by metastatic disease. A nuclear medicine CSF flow study also may be performed.

False Positives/Negatives

As previously stated, recent surgery can mimic LC because of postoperative leptomeningeal enhancement. Any procedure involving CSF access, including LP, can result in long-term dural enhancement that can mimic neoplasm.

Normally enhancing vessels on the surface of the cord can be mistaken for leptomeningeal tumor spread if the linearity of the vessel is not appreciated. These are usually venous structures, as the anterior and posterior spinal arteries usually run in the same location relative to the cord. Patients who have undergone radiation therapy to the spine may have dilated vessels that can mimic LC.

Meningitis may also mimic LC, and oncology patients are often predisposed to this secondary to immunosuppression and hospitalization.

Nuclear Imaging

Findings

The nuclear medicine study most commonly ordered in LC is a radioisotope CSF flow study to document the presence or absence of an obstruction to CSF flow in the spine or skull base. Although much less sensitive than MR to the presence of LC, CSF flow studies are considered almost 100% sensitive to the presence of obstructive CSF space disease. The procedure is performed by injecting Indium In 111–labeled diethylenetriamine pentaacetic acid (DTPA) into the CSF through either an LP or an indwelling catheter such as an Ommaya reservoir. Images generally are obtained for 60-90 minutes, and a 24-hour delayed image is frequently obtained.

In his 1998 article, Chamberlain describes the normal time for radioisotope to be seen in the different compartments following both lumbar and intraventricular injections and breaks down the intraventricular injections into adult and pediatric patients.

CSF flow studies are important when considering intrathecal chemotherapy, as in up to 70% of patients with LC some form of CSF flow obstruction exists that will affect the spread of the chemotherapeutic agent, thus its toxic effects and efficacy. Areas that demonstrate an obstruction on a CSF flow study can be treated with external beam radiation prior to intrathecal chemotherapy.

Degree of Confidence

As mentioned above, although the CSF flow study is not as sensitive as MR for the detection of any leptomeningeal tumor, the sensitivity, specificity, and accuracy for detection of CSF flow obstruction is 100%.

False Positives/Negatives

In CSF flow studies performed through a LP, ensure that the injection is within the subarachnoid space, as a subdural or epidural injection mimics a complete obstruction. Confirmation of needle placement using a small amount of contrast avoids this potential error.

Intervention

Medicolegal Pitfalls

• Failure to confirm leptomeningeal enhancement. As early diagnosis is important in LC, this can have serious consequences for the patient. Thus, administer contrast in all patients with a history of previous tumor or in those who have symptoms suggestive of LC, although the disease can be occult even with contrast. Noncontrast MR has proven of little use in detecting leptomeningeal disease and should be avoided in these patients. CT as well can easily miss disease, and normal contrast-enhanced CT scan does not exclude the presence of leptomeningeal tumor. The ordering physician must be aware that a normal MR or CT study does not exclude LC and that the combination of contrast MR and serial lumbar punctures has the best diagnostic potential.
• Radiologists often are asked to place the needle into the lumbar thecal sac prior to intrathecal chemotherapy administration. Confirmation of correct needle placement using intrathecal iodinated contrast is important, as an epidural or split injection results in a poor clinical outcome.

Multimedia

Media file 1: Axial T1-weighted postcontrast image demonstrates diffuse enhancement of the basal cisterns and leptomeninges from metastatic pilocytic astrocytoma. This appearance has been referred to as "zuckerguss" or sugar icing. In children, primitive neuroectodermal tumors are the most common cause of leptomeningeal carcinomatosis, but pilocytic astrocytomas (which are generally low grade) occasionally can demonstrate this type of aggressive behavior.

Media file 2: Sagittal T1-weighted postcontrast MR through the cervical spine in the same patient as Image 1. Note the diffuse enhancement of the subarachnoid space from extensive tumor deposits. Enhancing material surrounds the cord with no cerebrospinal fluid visible, giving the appearance of a T2 image. Marrow changes are consistent with prior radiation and/or chemotherapy.

Media file 3: Axial T1-weighted image postcontrast at the level of the inferior cerebellar peduncles demonstrates a more subtle case of leptomeningeal carcinomatosis, with faint thin enhancing tumor covering the peduncles and medulla (arrows). Note enhancement of cranial nerves IX and X on each side (arrowheads). This was a patient with leptomeningeal spread of a glioblastoma multiforme.

Media file 4: Sagittal T1-weighted postcontrast image of the lumbar spine with fat saturation reveals diffuse tumor seeding of the cauda equina from metastatic squamous cell carcinoma. Tiny tumor foci give a "string of beads" appearance to some of the nerve roots.

Media file 5: Sagittal T1 postcontrast image through the lumbar spine in this patient with small cell lung carcinoma demonstrates enhancing foci in the cauda equina and adjacent to the conus (arrows). In addition, notice the finely enhancing nerve root at the S1-2 level (arrowhead). This patient was experiencing lower extremity weakness.

Media file 6: Postcontrast CT of a patient with metastatic lung cancer and headache demonstrates contrast enhancement along the right parietal sulci with bilateral cortical edema.

Media file 7: Postcontrast fluid attenuated inversion recovery image demonstrates the use of this sequence in leptomeningeal carcinomatosis. Enhancement of the subarachnoid space is present scattered over both hemispheres, but most pronounced along the right parietal lobe in this patient with metastatic lung carcinoma.

Media file 8: Axial T1 postgadolinium in the same patient as Image 5 does not show the leptomeningeal tumor. Postcontrast fluid attenuated inversion recovery has been shown to be more sensitive than routine postcontrast T1 sequences in the detection of leptomeningeal carcinomatosis.

Media file 9: Coronal T1 postcontrast image demonstrates metastatic disease in this patient whose breast cancer was thought to be cured. Metastatic spread can occur decades after the initial tumor has been treated. Leptomeningeal carcinomatosis from a second primary is another possibility, and central nervous system spread of melanoma or lung cancer could have this appearance. Sarcoid also can demonstrate leptomeningeal spread.

References

1. Azzarelli B, Mirkin LD, Goheen M. The leptomeningeal vein. A site of re-entry of leukemic cells into the systemic circulation. Cancer. Oct 1 1984;54(7):1333-43. [Medline].

2. Balm M, Hammack J. Leptomeningeal carcinomatosis. Presenting features and prognostic factors [see comments]. Arch Neurol. Jul 1996;53(7):626-32. [Medline].

3. Benjamin R. Neurologic complications of prostate cancer. Am Fam Physician. May 1 2002;65(9):1834-40. [Medline].

4. Bokstein F, Lossos A, Siegal T. Leptomeningeal metastases from solid tumors: a comparison of two prospective series treated with and without intra-cerebrospinal fluid chemotherapy. Cancer. May 1 1998;82(9):1756-63. [Medline].

5. Chamberlain MC. Comparative spine imaging in leptomeningeal metastases. J Neuroonc. 1995;23:233-238.

6. Chamberlain MC. Leptomeningeal metastases. J Neurooncol. May 1998;37:271-284. [Medline].

7. Chamberlain MC. Radioisotope CSF flow studies in leptomeningeal metastases. J Neurooncol. Jun-Jul 1998;38(2-3):135-40. [Medline].

8. Collie DA, Brush JP, Lammie GA. Imaging features of leptomeningeal metastases. Clin Radiol. Nov 1999;54(11):765-71. [Medline].

9. Freilich RJ, Krol G, DeAngelis LM. Neuroimaging and cerebrospinal fluid cytology in the diagnosis of leptomeningeal metastasis. Ann Neurol. Jul 1995;38(1):51-7. [Medline].

10. Gomori JM, Heching N, Siegal T. Leptomeningeal metastases: evaluation by gadolinium enhanced spinal magnetic resonance imaging. J Neurooncol. Jan 1998;36(1):55-60. [Medline].

11. Grossman SA, Krabak MJ. Leptomeningeal carcinomatosis. Cancer Treat Rev. Apr 1999;25(2):103-19. [Medline].

12. Grossman SA, Moynihan TJ. Neoplastic meningitis. Neurol Clin. Nov 1991;9(4):843-56. [Medline].

13. Hildebrand J. Prophylaxis and treatment of leptomeningeal carcinomatosis in solid tumors of adulthood. J Neurooncol. Jun-Jul 1998;38(2-3):193-8. [Medline].

14. Kokkoris CP. Leptomeningeal carcinomatosis. How does cancer reach the pia-arachnoid?. Cancer. Jan 1 1983;51(1):154-60. [Medline].

15. Korkmaz M, Kim EE, Wong FC. In-111 DTPA Ommayagrams in leptomeningeal carcinomatosis. Clin Nucl Med. Jul 1995;20(7):610-2. [Medline].

16. Levy, LM. MR evaluation of the spine: cord/CSF motion. In: Magnetic Resonance Imaging Clinics of North America. 7(3), 9-1 to 9-15, 1999.

17. Mileshkin L, Michael M, O''Reilly M. CNS listeriosis confused with leptomeningeal carcinomatosis in a patient with a malignant insulinoma. Am J Clin Oncol. Dec 2002;25(6):576-9. [Medline].

18. Norris LK, Grossman SA, Olivi A. Neoplastic meningitis following surgical resection of isolated cerebellar metastasis: a potentially preventable complication. J Neurooncol. May 1997;32(3):215-23. [Medline].

19. Price RA, Johnson WW. The central nervous system in childhood leukemia. I. The arachnoid. Cancer. Mar 1973;31(3):520-33. [Medline].

20. Rodesch G, Van Bogaert P, Mavroudakis N. Neuroradiologic findings in leptomeningeal carcinomatosis: the value interest of gadolinium-enhanced MRI. Neuroradiology. 1990;32(1):26-32. [Medline].

21. Scanlon EF. James Ewing lecture. The process of metastasis. Cancer. 1985;55:1163-1166. [Medline].

22. Siebner HR, Grafin von Einsiedel H, Conrad B. Magnetic resonance ventriculography with gadolinium DTPA: report of two cases. Neuroradiology. Jun 1997;39(6):418-22; discussion 422. [Medline].

23. Singh SK, Agris JM, Leeds NE. Intracranial leptomeningeal metastases: comparison of depiction at FLAIR and contrast-enhanced MR imaging. Radiology. Oct 2000;217(1):50-3. [Medline].

24. Sze G. Diseases of the intracranial meninges: MR imaging features. AJR Am J Roentgenol. Apr 1993;160(4):727-33. [Medline].

25. Sze G, Soletsky S, Bronen R. MR imaging of the cranial meninges with emphasis on contrast enhancement and meningeal carcinomatosis. AJNR Am J Neuroradiol. Sep-Oct 1989;10(5):965-75. [Medline].

26. Tam JK, Bradley WG Jr, Goergen SK. Patterns of contrast enhancement in the pediatric spine at MR imaging with single- and triple-dose gadolinium. Radiology. Jan 1996;198(1):273-8. [Medline].

27. Tsuchiya K, Katase S, Yoshino A. Flair mr imaging for diagnosing intracranial meningeal carcinomatosis. AJR Am J Roentgenol. Jun 2001;176(6):1585-8. [Medline].

28. Watanabe M, Tanaka R, Takeda N. Correlation of MRI and clinical features in meningeal carcinomatosis. Neuroradiology. 1993;35(7):512-5. [Medline].

29. Yousem DM, Patrone PM, Grossman RI. Leptomeningeal metastases: MR evaluation. J Comput Assist Tomogr. Mar-Apr 1990;14(2):255-61. [Medline].

30. Zachariah B, Zachariah SB, Varghese R. Carcinomatous meningitis: clinical manifestations and management. Int J Clin Pharmacol Ther. Jan 1995;33(1):7-12. [Medline].

31. van Oostenbrugge RJ, Twijnstra A. Presenting features and value of diagnostic procedures in leptomeningeal metastases. Neurology. Jul 22 1999;53(2):382-5. [Medline].

Keywords

leptomeningeal carcinomatosis, leptomeningeal metastases, arachnoid metastases, zuckerguss, LC

Contributor Information and Disclosures

Author

Andrew L Wagner, MD, Assistant Professor of Radiology, Instructional Faculty, University of Virginia School of Medicine; Director of Neuroradiology, Department of Radiology, Rockingham Memorial Hospital
Andrew L Wagner, MD is a member of the following medical societies: American College of Radiology, American Roentgen Ray Society, American Society of Neuroradiology, and Radiological Society of North America
Disclosure: Nothing to disclose.

Medical Editor

Lucien M Levy, MD, PhD, Director of Neuroradiology, Professor of Radiology, Department of Radiology, George Washington University Medical Center
Lucien M Levy, MD, PhD is a member of the following medical societies: American Cancer Society, American College of Radiology, American Heart Association, American Medical Association, American Roentgen Ray Society, American Society of Neuroradiology, and Radiological Society of North America
Disclosure: Nothing to disclose.

Pharmacy Editor

Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand
Disclosure: Nothing to disclose.

Managing Editor

Val Runge, MD, Robert and Alma Moreton Centennial Chair in Radiology, Professor, Editor-in-Chief of Investigative Radiology, Department of Radiology, Scott and White Clinic and Hospital
Val Runge, MD is a member of the following medical societies: Society for Health and Human Values
Disclosure: Nothing to disclose.

CME Editor

Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute
Robert M Krasny, MD is a member of the following medical societies: American Roentgen Ray Society and Radiological Society of North America
Disclosure: Nothing to disclose.

Chief Editor

James G Smirniotopoulos, MD, Professor of Radiology, Neurology, and Biomedical Informatics, Chairman, Department of Radiology and Radiological Sciences, Uniformed Services University of the Health Sciences
James G Smirniotopoulos, MD is a member of the following medical societies: American College of Radiology, American Roentgen Ray Society, American Society of Head and Neck Radiology, American Society of Neuroradiology, American Society of Pediatric Neuroradiology, Association of University Radiologists, and Radiological Society of North America
Disclosure: Nothing to disclose.

© 1994- by Medscape.
All Rights Reserved
(http://www.medscape.com/public/copyright)