Clinical Neurology and Neurosurgery 120 (2014) 116–119
Contents lists available at ScienceDirect
Clinical Neurology and Neurosurgery journal homepage: www.elsevier.com/locate/clineuro
Case Report
Perineural spread of malignant mesothelioma with spinal intramedullary involvement夽 Manoj Tanwar a , Charles B. Simone II b , Steven Newman a , Keith Cengel b , Gordon H. Yu c , Elias R. Melhem a , Suyash Mohan a,∗ a
Department of Radiology, Neuroradiology Division, Perelman School of Medicine at University of Pennsylvania, Philadelphia, 19104, USA Department of Radiation Oncology, Perelman School of Medicine at University of Pennsylvania, Philadelphia, 19104, USA c Department of Pathology and Laboratory Medicine, Perelman School of Medicine at University of Pennsylvania, Philadelphia, 19104, USA b
a r t i c l e
i n f o
Article history: Received 22 November 2013 Received in revised form 2 March 2014 Accepted 5 March 2014 Available online 13 March 2014 Keywords: Malignant pleural mesothelioma Perineural spread Spinal cord neoplasm Intramedullary tumor Magnetic resonance imaging
1. Introduction Malignant pleural mesothelioma is an uncommon but aggressive malignancy. Its incidence is approximately 1.05 per 100,000 persons in the United States, with an estimated 3200 new cases annually. Even with multimodal treatment, most commonly pemetrexed-based chemotherapy, median survival is approximately one year after diagnosis, and cure is exceedingly rare. Most patients are found to have an epithelioid histology, which is associated with a prolonged survival as compared with the sarcomatoid, biphasic, and desmoplastic types. Patterns of failure after chemotherapy and surgery are predominantly local, and mesothelioma frequently demonstrates localized direct invasion and lymphatic spread in the thorax. However, there are very few reports of spinal cord involvement. The mechanism of spread includes direct extension or hematogenous or perineural
夽 An abstract from this manuscript was presented as an Electronic Excerpta at the ASNR 51st Annual Meeting and The Foundation of the ASNR Symposium 2013, San Diego (18th–23rd May, 2013). ∗ Corresponding author at: Department of Radiology, Division of Neuroradiology, Perelman School of Medicine at University of Pennsylvania, 219 Dulles Building, 3400 Spruce Street, Philadelphia, PA 19104, USA. Tel.: +1 215 662 6865; fax: +1 215 662 3283. E-mail address: [email protected] (S. Mohan). http://dx.doi.org/10.1016/j.clineuro.2014.03.005 0303-8467/© 2014 Elsevier B.V. All rights reserved.
spread. Perineural spread is extremely rare, and to the best of our knowledge, only seven cases have been reported previously [1–7] (Table 1). We report a case of malignant pleural mesothelioma, which demonstrated retrograde perineural spread along an intercostal nerve to involve the spinal cord, with a review of existing literature. 2. Case report A 76-year-old man initially started having complaints of left shoulder pain 10 months ago, and was found to have a rotator cuff tear, which was also confirmed on MRI shoulder. He also felt pain in his left anterior chest and lower posterior chest. Evaluation with CT demonstrated multi-lobulated pleural-based masses throughout left hemithorax involving both medial and lateral surfaces, which were confirmed to be malignant mesothelioma with mixed epithelial and sarcomatoid histology on pathologic examination. Based on his age, extensive disease with infiltration through diaphragm into the intra-abdominal fat adjacent to the spleen, and his history of heart disease, especially past CABG; he was not considered a surgical candidate. He was treated with chemotherapy with pemetrexed and carboplatin for six cycles with partial response, followed by maintenance pemetrexed. Reimaging after two cycles of maintenance therapy revealed stable disease. Shortly thereafter, he then developed recurrence of his left chest wall pain. Reimaging the
Table 1 Review of previous cases who presented with perineural spinal intramedullary involvement. Age (yrs)
Sex
Nerve root(s) involved
Presentation/Interval between MM diagnosis and spinal metastases
Imaging findings/Histology
Therapeutic intervention
Treatment response
Post presentation survival
Cooper [6]
67
M
Several nerve roots in T8 region
Paraplegia, urinary incontinence, shoulder pain/NA
NA
NA
NA
Steel et al. [1]
54
M
T1
NA
55
F
T9
Presence of a clean plane for dissection, total resection NA
Improved sensation, lower-extremity function
Lee et al. [7]
NA
NA
Hillard et al. [2]
61
M
C8-T1
Brown-Sequard syndrome, Horner’s syndrome, thoracic sensory level/3 years Thoracic & lumbar pain, paraparesis, LE hypertonia & hyperreflexia + Babinski, sensory level/18 months Upper & lower extremity weakness, Horner’s syndrome, decreased sensations, up-going toes/2 years
Autopsy-nodular dural & nerve roots thickening, deposits within spinal cord substance/Biphasic Enhancing material coating & infiltrating spinal cord/Epithelioid-Bisphasic Soft tissue extension into neural foramina, spinal cord compression/NA
Partial resection, followed by radiation therapy
Improvement in strength
NA
Payer and von Briel [5]
50
M
T4
Absence of a clean plane, subtotal resection
Chest pain reduction, no neurological change
6 months
Okura et al. [4]
61
M
T4
Absence of a clean plane, subtotal resection
Neurological condition unchanged, slight sensation improvement
3 months
Richter et al. [3]
64
M
T1–T2
Partial resection, followed by radiation therapy
NA
Present case
76
M
T6
Immediate post-op spastic paraparesis aggravation, back to pre-op activity with physiotherapy Improvement in strength and sensation, reduced pain
Chest pain, partial Brown-Sequard syndrome increased DTR, tactile hypesthesia, and sphincter disturbance/28 months Paraparesis, LE numbness + Babinski, micturition & defecation dysfunction, sensory level/7 months Chest pain, upper extremity pain, weakness, worsening gait, spastic paraparesis/At the same time Lower extremity weakness, numbness/10 months
Soft tissue extension into neural foramina, epidural extension, spinal cord enhancement, expansion with central edema/Epithelioid Enhancing vertebral mass extending through intervertebral foramen into spinal cord, diffuse intramedullary signal/Sarcomatoid Enhancing spinal cord mass, extensive perifocal edema/Sarcomatoid Paraspinal tumor infiltrating into foramen, myelopathy with spinal cord edema and tethering/Desmoplastic Pleural mass invading paraspinous soft tissues, ribs, posterior chest wall. Soft tissue abnormality extending along T6 nerve & nerve roots, extramedullary mass, enhancing spinal cord mass with edema/Mixed epithelial and sarcomatoid
Fractionated radiation therapy
1.7 months
M. Tanwar et al. / Clinical Neurology and Neurosurgery 120 (2014) 116–119
Authors (Year)
Abbreviations: DTR, deep tendon reflex; LE, lower extremity; MM, malignant mesothelioma; NA, not available.
117
118
M. Tanwar et al. / Clinical Neurology and Neurosurgery 120 (2014) 116–119
Fig. 1. Axial T1-weighted post gadolinium images (A and B) of the thoracic spine showing a pleural mass invading the chest wall (thick open arrows) with perineural involvement of the left T6 nerve in the foramen (thick solid arrow), as well as associated intramedullary involvement (arrowhead) through retrograde extension along the left T6 ventral and dorsal nerve roots (thin arrows). Sagittal T1-weighted post gadolinium image (C) demonstrating an enhancing intramedullary mass (thick arrow) spanning the T5 and T6 vertebral levels, with associated cord edema (arrowheads) spanning from T4 through T9 on sagittal T2-weighted image (D). Cell block preparation of CT-guided FNA (E) from a paraspinal mass demonstrates atypical cells infiltrating dense fibrous tissue most consistent with mesothelioma (Hematoxylin & Eosin stain, ×600).
next month revealed progressive intra-thoracic disease, and he was started on intensity modulated radiation therapy (IMRT) to the sites of bulky lateral chest wall disease. While receiving this treatment, he presented with 3 days of worsening weakness in the bilateral lower extremities with associated bilateral numbness. Neurological examination revealed a new reduction in motor strength of 3/5 in the left and 4/5 in the right lower extremity, as well as decreased light touch sensation in a symmetric stocking distribution. There was no associated bowel or bladder dysfunction. Post gadolinium enhanced MRI of the spine demonstrated a 5.8 cm pleural-based mass (Fig. 1A) invading left lateral paraspinous soft tissues, 6th, 7th and 8th ribs, and posterior chest wall. The enhancing soft tissue abnormality (Fig. 1A and B) followed the course of the left 6th intercostal nerve, through the T6-7 intervertebral foramen into the spinal canal, and further extending into the spinal cord. Thickened enhancing dorsal and ventral T6 nerve roots (Fig. 1B) with an associated enhancing intra- and extra-medullary mass were present. The spinal cord showed an enhancing abnormality spanning T5 and T6 segments (Fig. 1C), with accompanying extensive cord edema from T4 to T9 on T2-weighted MR images (Fig. 1D). Based on the clinical presentation and imaging findings, a diagnosis of perineural spread of malignant pleural mesothelioma with extramedullary and intramedullary spinal cord involvement was proposed. CT-guided fine needle aspiration (FNA) cytology of the paraspinal mass immediately lateral to the intervertebral foramen (Fig. 1E) demonstrated fragments of fibroconnective tissue with atypical spindle and epithelioid cells, most consistent with mesothelioma. With his intramedullary spinal cord involvement and extensive disease, he was considered a poor surgical candidate. He was started on decadron and palliative external beam radiation therapy to the thoracic spine in 250 cGy daily fractions to 3500 cGy.
With this treatment, the patient achieved a reduction in pain and demonstrated improvements in lower extremity strength and sensation. An early radiographic response to radiotherapy was also demonstrated (Fig. 2A–C). However, within a couple of days of the completion of his fractionated radiation therapy, the patient developed urinary retention and acute worsening of right lower extremity weakness, with motor strength decreasing from 4/5 to 2/5. MRI of the spine demonstrated interval-decreased enhancement in intramedullary tumor with decreased cord edema in the mid-thoracic spine region, but interval appearance of a new enhancing lesion at the right side of conus medullaris at L1 level. A single 800 cGy high-dose fraction of radiation therapy was delivered to T12-L3 levels. Despite initial slight improvement in weakness, the patient eventually succumbed to his disease, nearly after 1.7 months of presenting with his intramedullary involvement. 3. Discussion Malignant mesothelioma is an aggressive malignancy, which originates from the mesothelium of body cavities. In cases of pleural malignant mesothelioma, it is common for tumor to infiltrate locally, but spinal cord involvement is uncommon. Development of spinal cord metastases has been associated with a shortened survival. Only a handful of cases previously reported have described spinal cord involvement through perineural spread (Table 1). Clinical presentation varies according to the segment of spinal cord involved, and symptoms can include pain, Horner’s syndrome, upper and/or lower extremity motor and sensory disturbances, and sphincter dysfunction [1–7]. These are consequential to compression, infiltration, or tethering of the spinal cord. Our
M. Tanwar et al. / Clinical Neurology and Neurosurgery 120 (2014) 116–119
119
Fig. 2. Post palliative radiation therapy follow-up MRI demonstrated an interval decreased size of the pleural mass (thick open arrow, A), as well as decreased size of the enhancing intramedullary abnormality (thick solid arrow, B) and diminished associated cord edema (between arrowheads, C).
patient presented with complaints of weakness and numbness in the bilateral lower extremities, and he subsequently developed bladder dysfunction. For intramedullary spinal cord metastases, the imaging modality of choice is MRI. However, in cases of malignant mesothelioma, intradural compartment involvement and exact spread mechanism are not always evident on imaging [1–5,7]. Minimally invasive FNA can be used to complement the MRI findings, and to confirm the tissue diagnosis of metastases. In our case, contrastenhanced MRI of the spine clearly demonstrated a pleural-based soft tissue mass with associated signal abnormality following the intercostal nerve, and dorsal and ventral nerve roots into the spinal cord substance. Subsequent image-guided needle aspiration cytology essentially confirmed malignant mesothelioma. The best treatment modality for patients with intradural extension of malignancy is unclear, with the primary aim being symptomatic relief and prevention of further neurological deterioration. Therapeutic options include microsurgery, radiation therapy, and chemotherapy. Surgical resection offers the most rapid symptomatic relief and may be possible, depending on the presence of a clean plane of dissection between the tumor and normal spinal cord [1]. Surgery is often optimally followed by radiation therapy in an attempt to further improve local control and delay the recurrence of neural involvement by the tumor, particularly in cases where an incomplete resection is performed [2,3]. In cases where there is an absence of a plane of dissection, a subtotal resection can be considered [4,5]. Alternatively, and for cases with extensive disease or in patients who are not otherwise surgical candidates, radiation therapy should be considered. Local treatment response is typically most delayed and least complete with chemotherapy, and the use of chemotherapy for intradural extension is most typically used for highly chemoresponsive diseases like small cell lung cancer or Hodgkin’s lymphoma. High dose steroids are suitable for patients with rapidly progressive cord compression
symptoms due to edema [1]. Our patient was considered a poor surgical candidate, and hence he received radiation therapy along with steroids that achieved an initial improvement in his symptoms. 4. Conclusion In malignant pleural mesothelioma cases presenting with new neurological symptoms, a diagnosis of perineural spinal intramedullary involvement should be considered. Contrast enhanced MRI, with subsequent confirmation with FNA cytology can be optimally used for the assessment of these cases. Our case was unique in that the imaging clearly demonstrated the retrograde path of perineural spread along the intercostal nerve and thoracic nerve roots. In addition, treatment for these cases is variable and can include surgery, radiation therapy, and systemic therapy depending on the clinical scenario and extent of the disease. As the prognosis for these cases is dismal, symptomatic relief and prevention of neurological deterioration are critical. References [1] Steel TR, Allibone J, Revesz T, D’Arrigo C, Crockard HA. Intradural neurotropic spread of malignant mesothelioma. Case report and review of the literature. J Neurosurg 1998;88:122–5. [2] Hillard VH, Liu JK, Kwok A, Schmidt MH. Perineural spread of malignant mesothelioma resulting in an intradural spinal cord mass: case report. J Neurooncol 2007;81:185–9. [3] Richter H, Hildebrandt G, Heilbronner R. Intradural perineural spread of mesothelioma causing myelopathy by tethering of the spinal cord. J Neurol Surg A Cent Eur Neurosurg 2012;73:111–5. [4] Okura H, Suga Y, Akiyama O, Kudo K, Tsutsumi S, Abe Y, et al. Pleural malignant mesothelioma causing cord infiltration through the nerve root. Case report. Neurol Med Chir (Tokyo) 2009;49:167–71. [5] Payer M, von Briel T. Intradural pleural malignant mesothelioma. Acta Neurochir (Wien) 2007;149:1053–6 [discussion 1056]. [6] Cooper D. Malignant mesothelioma invading the spinal canal. Postgrad Med J 1974;50:718–23. [7] Lee AWM, Nikitins I, Pozza C, Koblar SA. Pleural mesothelioma with extension into the thoracic spinal cord. Intern Med J 2005;35:195–6.
Contents lists available at ScienceDirect
Clinical Neurology and Neurosurgery journal homepage: www.elsevier.com/locate/clineuro
Case Report
Perineural spread of malignant mesothelioma with spinal intramedullary involvement夽 Manoj Tanwar a , Charles B. Simone II b , Steven Newman a , Keith Cengel b , Gordon H. Yu c , Elias R. Melhem a , Suyash Mohan a,∗ a
Department of Radiology, Neuroradiology Division, Perelman School of Medicine at University of Pennsylvania, Philadelphia, 19104, USA Department of Radiation Oncology, Perelman School of Medicine at University of Pennsylvania, Philadelphia, 19104, USA c Department of Pathology and Laboratory Medicine, Perelman School of Medicine at University of Pennsylvania, Philadelphia, 19104, USA b
a r t i c l e
i n f o
Article history: Received 22 November 2013 Received in revised form 2 March 2014 Accepted 5 March 2014 Available online 13 March 2014 Keywords: Malignant pleural mesothelioma Perineural spread Spinal cord neoplasm Intramedullary tumor Magnetic resonance imaging
1. Introduction Malignant pleural mesothelioma is an uncommon but aggressive malignancy. Its incidence is approximately 1.05 per 100,000 persons in the United States, with an estimated 3200 new cases annually. Even with multimodal treatment, most commonly pemetrexed-based chemotherapy, median survival is approximately one year after diagnosis, and cure is exceedingly rare. Most patients are found to have an epithelioid histology, which is associated with a prolonged survival as compared with the sarcomatoid, biphasic, and desmoplastic types. Patterns of failure after chemotherapy and surgery are predominantly local, and mesothelioma frequently demonstrates localized direct invasion and lymphatic spread in the thorax. However, there are very few reports of spinal cord involvement. The mechanism of spread includes direct extension or hematogenous or perineural
夽 An abstract from this manuscript was presented as an Electronic Excerpta at the ASNR 51st Annual Meeting and The Foundation of the ASNR Symposium 2013, San Diego (18th–23rd May, 2013). ∗ Corresponding author at: Department of Radiology, Division of Neuroradiology, Perelman School of Medicine at University of Pennsylvania, 219 Dulles Building, 3400 Spruce Street, Philadelphia, PA 19104, USA. Tel.: +1 215 662 6865; fax: +1 215 662 3283. E-mail address: [email protected] (S. Mohan). http://dx.doi.org/10.1016/j.clineuro.2014.03.005 0303-8467/© 2014 Elsevier B.V. All rights reserved.
spread. Perineural spread is extremely rare, and to the best of our knowledge, only seven cases have been reported previously [1–7] (Table 1). We report a case of malignant pleural mesothelioma, which demonstrated retrograde perineural spread along an intercostal nerve to involve the spinal cord, with a review of existing literature. 2. Case report A 76-year-old man initially started having complaints of left shoulder pain 10 months ago, and was found to have a rotator cuff tear, which was also confirmed on MRI shoulder. He also felt pain in his left anterior chest and lower posterior chest. Evaluation with CT demonstrated multi-lobulated pleural-based masses throughout left hemithorax involving both medial and lateral surfaces, which were confirmed to be malignant mesothelioma with mixed epithelial and sarcomatoid histology on pathologic examination. Based on his age, extensive disease with infiltration through diaphragm into the intra-abdominal fat adjacent to the spleen, and his history of heart disease, especially past CABG; he was not considered a surgical candidate. He was treated with chemotherapy with pemetrexed and carboplatin for six cycles with partial response, followed by maintenance pemetrexed. Reimaging after two cycles of maintenance therapy revealed stable disease. Shortly thereafter, he then developed recurrence of his left chest wall pain. Reimaging the
Table 1 Review of previous cases who presented with perineural spinal intramedullary involvement. Age (yrs)
Sex
Nerve root(s) involved
Presentation/Interval between MM diagnosis and spinal metastases
Imaging findings/Histology
Therapeutic intervention
Treatment response
Post presentation survival
Cooper [6]
67
M
Several nerve roots in T8 region
Paraplegia, urinary incontinence, shoulder pain/NA
NA
NA
NA
Steel et al. [1]
54
M
T1
NA
55
F
T9
Presence of a clean plane for dissection, total resection NA
Improved sensation, lower-extremity function
Lee et al. [7]
NA
NA
Hillard et al. [2]
61
M
C8-T1
Brown-Sequard syndrome, Horner’s syndrome, thoracic sensory level/3 years Thoracic & lumbar pain, paraparesis, LE hypertonia & hyperreflexia + Babinski, sensory level/18 months Upper & lower extremity weakness, Horner’s syndrome, decreased sensations, up-going toes/2 years
Autopsy-nodular dural & nerve roots thickening, deposits within spinal cord substance/Biphasic Enhancing material coating & infiltrating spinal cord/Epithelioid-Bisphasic Soft tissue extension into neural foramina, spinal cord compression/NA
Partial resection, followed by radiation therapy
Improvement in strength
NA
Payer and von Briel [5]
50
M
T4
Absence of a clean plane, subtotal resection
Chest pain reduction, no neurological change
6 months
Okura et al. [4]
61
M
T4
Absence of a clean plane, subtotal resection
Neurological condition unchanged, slight sensation improvement
3 months
Richter et al. [3]
64
M
T1–T2
Partial resection, followed by radiation therapy
NA
Present case
76
M
T6
Immediate post-op spastic paraparesis aggravation, back to pre-op activity with physiotherapy Improvement in strength and sensation, reduced pain
Chest pain, partial Brown-Sequard syndrome increased DTR, tactile hypesthesia, and sphincter disturbance/28 months Paraparesis, LE numbness + Babinski, micturition & defecation dysfunction, sensory level/7 months Chest pain, upper extremity pain, weakness, worsening gait, spastic paraparesis/At the same time Lower extremity weakness, numbness/10 months
Soft tissue extension into neural foramina, epidural extension, spinal cord enhancement, expansion with central edema/Epithelioid Enhancing vertebral mass extending through intervertebral foramen into spinal cord, diffuse intramedullary signal/Sarcomatoid Enhancing spinal cord mass, extensive perifocal edema/Sarcomatoid Paraspinal tumor infiltrating into foramen, myelopathy with spinal cord edema and tethering/Desmoplastic Pleural mass invading paraspinous soft tissues, ribs, posterior chest wall. Soft tissue abnormality extending along T6 nerve & nerve roots, extramedullary mass, enhancing spinal cord mass with edema/Mixed epithelial and sarcomatoid
Fractionated radiation therapy
1.7 months
M. Tanwar et al. / Clinical Neurology and Neurosurgery 120 (2014) 116–119
Authors (Year)
Abbreviations: DTR, deep tendon reflex; LE, lower extremity; MM, malignant mesothelioma; NA, not available.
117
118
M. Tanwar et al. / Clinical Neurology and Neurosurgery 120 (2014) 116–119
Fig. 1. Axial T1-weighted post gadolinium images (A and B) of the thoracic spine showing a pleural mass invading the chest wall (thick open arrows) with perineural involvement of the left T6 nerve in the foramen (thick solid arrow), as well as associated intramedullary involvement (arrowhead) through retrograde extension along the left T6 ventral and dorsal nerve roots (thin arrows). Sagittal T1-weighted post gadolinium image (C) demonstrating an enhancing intramedullary mass (thick arrow) spanning the T5 and T6 vertebral levels, with associated cord edema (arrowheads) spanning from T4 through T9 on sagittal T2-weighted image (D). Cell block preparation of CT-guided FNA (E) from a paraspinal mass demonstrates atypical cells infiltrating dense fibrous tissue most consistent with mesothelioma (Hematoxylin & Eosin stain, ×600).
next month revealed progressive intra-thoracic disease, and he was started on intensity modulated radiation therapy (IMRT) to the sites of bulky lateral chest wall disease. While receiving this treatment, he presented with 3 days of worsening weakness in the bilateral lower extremities with associated bilateral numbness. Neurological examination revealed a new reduction in motor strength of 3/5 in the left and 4/5 in the right lower extremity, as well as decreased light touch sensation in a symmetric stocking distribution. There was no associated bowel or bladder dysfunction. Post gadolinium enhanced MRI of the spine demonstrated a 5.8 cm pleural-based mass (Fig. 1A) invading left lateral paraspinous soft tissues, 6th, 7th and 8th ribs, and posterior chest wall. The enhancing soft tissue abnormality (Fig. 1A and B) followed the course of the left 6th intercostal nerve, through the T6-7 intervertebral foramen into the spinal canal, and further extending into the spinal cord. Thickened enhancing dorsal and ventral T6 nerve roots (Fig. 1B) with an associated enhancing intra- and extra-medullary mass were present. The spinal cord showed an enhancing abnormality spanning T5 and T6 segments (Fig. 1C), with accompanying extensive cord edema from T4 to T9 on T2-weighted MR images (Fig. 1D). Based on the clinical presentation and imaging findings, a diagnosis of perineural spread of malignant pleural mesothelioma with extramedullary and intramedullary spinal cord involvement was proposed. CT-guided fine needle aspiration (FNA) cytology of the paraspinal mass immediately lateral to the intervertebral foramen (Fig. 1E) demonstrated fragments of fibroconnective tissue with atypical spindle and epithelioid cells, most consistent with mesothelioma. With his intramedullary spinal cord involvement and extensive disease, he was considered a poor surgical candidate. He was started on decadron and palliative external beam radiation therapy to the thoracic spine in 250 cGy daily fractions to 3500 cGy.
With this treatment, the patient achieved a reduction in pain and demonstrated improvements in lower extremity strength and sensation. An early radiographic response to radiotherapy was also demonstrated (Fig. 2A–C). However, within a couple of days of the completion of his fractionated radiation therapy, the patient developed urinary retention and acute worsening of right lower extremity weakness, with motor strength decreasing from 4/5 to 2/5. MRI of the spine demonstrated interval-decreased enhancement in intramedullary tumor with decreased cord edema in the mid-thoracic spine region, but interval appearance of a new enhancing lesion at the right side of conus medullaris at L1 level. A single 800 cGy high-dose fraction of radiation therapy was delivered to T12-L3 levels. Despite initial slight improvement in weakness, the patient eventually succumbed to his disease, nearly after 1.7 months of presenting with his intramedullary involvement. 3. Discussion Malignant mesothelioma is an aggressive malignancy, which originates from the mesothelium of body cavities. In cases of pleural malignant mesothelioma, it is common for tumor to infiltrate locally, but spinal cord involvement is uncommon. Development of spinal cord metastases has been associated with a shortened survival. Only a handful of cases previously reported have described spinal cord involvement through perineural spread (Table 1). Clinical presentation varies according to the segment of spinal cord involved, and symptoms can include pain, Horner’s syndrome, upper and/or lower extremity motor and sensory disturbances, and sphincter dysfunction [1–7]. These are consequential to compression, infiltration, or tethering of the spinal cord. Our
M. Tanwar et al. / Clinical Neurology and Neurosurgery 120 (2014) 116–119
119
Fig. 2. Post palliative radiation therapy follow-up MRI demonstrated an interval decreased size of the pleural mass (thick open arrow, A), as well as decreased size of the enhancing intramedullary abnormality (thick solid arrow, B) and diminished associated cord edema (between arrowheads, C).
patient presented with complaints of weakness and numbness in the bilateral lower extremities, and he subsequently developed bladder dysfunction. For intramedullary spinal cord metastases, the imaging modality of choice is MRI. However, in cases of malignant mesothelioma, intradural compartment involvement and exact spread mechanism are not always evident on imaging [1–5,7]. Minimally invasive FNA can be used to complement the MRI findings, and to confirm the tissue diagnosis of metastases. In our case, contrastenhanced MRI of the spine clearly demonstrated a pleural-based soft tissue mass with associated signal abnormality following the intercostal nerve, and dorsal and ventral nerve roots into the spinal cord substance. Subsequent image-guided needle aspiration cytology essentially confirmed malignant mesothelioma. The best treatment modality for patients with intradural extension of malignancy is unclear, with the primary aim being symptomatic relief and prevention of further neurological deterioration. Therapeutic options include microsurgery, radiation therapy, and chemotherapy. Surgical resection offers the most rapid symptomatic relief and may be possible, depending on the presence of a clean plane of dissection between the tumor and normal spinal cord [1]. Surgery is often optimally followed by radiation therapy in an attempt to further improve local control and delay the recurrence of neural involvement by the tumor, particularly in cases where an incomplete resection is performed [2,3]. In cases where there is an absence of a plane of dissection, a subtotal resection can be considered [4,5]. Alternatively, and for cases with extensive disease or in patients who are not otherwise surgical candidates, radiation therapy should be considered. Local treatment response is typically most delayed and least complete with chemotherapy, and the use of chemotherapy for intradural extension is most typically used for highly chemoresponsive diseases like small cell lung cancer or Hodgkin’s lymphoma. High dose steroids are suitable for patients with rapidly progressive cord compression
symptoms due to edema [1]. Our patient was considered a poor surgical candidate, and hence he received radiation therapy along with steroids that achieved an initial improvement in his symptoms. 4. Conclusion In malignant pleural mesothelioma cases presenting with new neurological symptoms, a diagnosis of perineural spinal intramedullary involvement should be considered. Contrast enhanced MRI, with subsequent confirmation with FNA cytology can be optimally used for the assessment of these cases. Our case was unique in that the imaging clearly demonstrated the retrograde path of perineural spread along the intercostal nerve and thoracic nerve roots. In addition, treatment for these cases is variable and can include surgery, radiation therapy, and systemic therapy depending on the clinical scenario and extent of the disease. As the prognosis for these cases is dismal, symptomatic relief and prevention of neurological deterioration are critical. References [1] Steel TR, Allibone J, Revesz T, D’Arrigo C, Crockard HA. Intradural neurotropic spread of malignant mesothelioma. Case report and review of the literature. J Neurosurg 1998;88:122–5. [2] Hillard VH, Liu JK, Kwok A, Schmidt MH. Perineural spread of malignant mesothelioma resulting in an intradural spinal cord mass: case report. J Neurooncol 2007;81:185–9. [3] Richter H, Hildebrandt G, Heilbronner R. Intradural perineural spread of mesothelioma causing myelopathy by tethering of the spinal cord. J Neurol Surg A Cent Eur Neurosurg 2012;73:111–5. [4] Okura H, Suga Y, Akiyama O, Kudo K, Tsutsumi S, Abe Y, et al. Pleural malignant mesothelioma causing cord infiltration through the nerve root. Case report. Neurol Med Chir (Tokyo) 2009;49:167–71. [5] Payer M, von Briel T. Intradural pleural malignant mesothelioma. Acta Neurochir (Wien) 2007;149:1053–6 [discussion 1056]. [6] Cooper D. Malignant mesothelioma invading the spinal canal. Postgrad Med J 1974;50:718–23. [7] Lee AWM, Nikitins I, Pozza C, Koblar SA. Pleural mesothelioma with extension into the thoracic spinal cord. Intern Med J 2005;35:195–6.
