PRIMARY CP ANGLE MEDULLOBLASTOMA

PRIMARY CEREBELLO-PONTINE ANGLE MEDULLOBLASTOMA: 

1 PRIMARY CEREBELLO-PONTINE ANGLE MEDULLOBLASTOMA Dr. Prabesh Kumar Choudhary 2 nd Yr Resident, MD( Path), NAMS

Clinical presentation: 

2 Clinical presentation An 18 years female, Gastro OPD Vomiting and headache for 15 days Neurological consultation: features of raised intracranial pressure No neurological deficits or cerebellar signs An urgent CT revealed obstructed hydrocephalus with Rt. CP angle mass Ventriculo-peritoneal shunt was performed

CT scan: 

3 CT scan Extra-axial, infratentorial well defined lesion in Rt. CP angle. Homogenously enhancing. Mild mass effect. Impression: Meningioma

MRI: 

4 MRI Well delineated extraxial mass in Rt. CP angle Heterogenously enhancing Impression: Suggestive of Meningioma

Intraoperative findings: 

5 Intraoperative findings Total excision Encapsulated, grayish pink, well delineated mass in Rt. CP angle Suckable and soft in consistency No cerebellar continuity

Macroscopy: 

6 Macroscopy Received formalin fixed specimen labelled as “CP angle mass” Multiple pieces, grayish white and measures 7 x 6cm P/E- 2B Routinely processed and H & E staining done

Histopathology: 

7 Histopathology Dense cellularity Nodules Pale and less cellular in centre Dark and more cellular at periphery

Histopathology, Contd;: 

8 Histopathology, Contd; Hyperchromatic carrot cells Primitive looking monotonous small round to oval cells with scanty cytoplasm and high N/C ratio Impression: Medulloblastoma A panel of immunohistochemistry advised.

Immunohistochemistry: 

9 Immunohistochemistry EMA: Negative GFAP: Negative LCA: Negative Synaptophysin : focally positive Final impression: Medulloblastoma , WHO grade IV

PowerPoint Presentation: 

10 LITERATURE REVIEW

Age and sex distribution: 

11 Age and sex distribution Number of cases Females 50 100 150 200 250 250 200 150 100 50 0 90-100 80-89 70-79 60-69 20-29 30-39 40-49 50-59 10-19 0-9 Number of cases Males 0

Localization: 

12 Localization Vermis: 75% of childhood cases Cerebellar hemispheres: adults CP angle: 19 cases

Reported cases of CP angle medulloblastoma: 

13 Reported cases of CP angle medulloblastoma Authors No of cases Age distribution Mahapatra et al. 14 3 to 53 (23.5) Yrs Rajkumar et al. 02 8 & 9 Yrs Naim-ur-Rehman 01 3 Yrs

Postulated hypothesis: 

14 Postulated hypothesis Origin: still controversy Kadin and Rubinstein: germinal cells (or their remnants) anywhere along their migratory path : lateral location in adults; CP angle medulloblastoma : remnants of external granular layer in cerebellar hemisphere, including flocculus which faces the CP angle.

Postulated hypothesis; Contd: 

15 Postulated hypothesis; Contd Ringertz and Tola proposed that CPA medulloblastomas may originate from a proliferating residue of lateral medullary velum Lateral extension to CPA through foramen of Luschka

Treatment and prognosis: 

16 Treatment and prognosis Treatment still not established because of small number of reported cases With surgery and radiation a total of 30% of 5-year survival has been reported for CP angle medulloblastoma Chemotherapy has been also combined with radiotherapy with improvement in some cases Most evidence favors surgery along with radiotherapy as the main treatment modality

Conclusion: 

17 Conclusion Medulloblastoma is predominantly a childhood tumor that almost always presents intra-axially. However, it is important to consider the rare possibility of medulloblastoma in the CP angle which can confuse the nature of the lesion and affect the course of treatment.

References: 

18 References 1. J.L. House and M.R. Burt, Primary CNS tumors presenting as cerebellopontine angle tumours. Am. J. Otol. suppl (1985), pp. 147–153 2. S. Yamada, T. Aiba and M. Hara, Cerebellopontine angle medulloblastoma: case report and literature review. Br. J. Neurosurg. 7 (1993), pp. 91–94. 3. Naim-ur-Rehman, A. Jamjoom, M. Al-Rayees and Z.A. Jamjoom, Cerebellopontine medulloblastoma. Br. J. Neurosurg. 14 (2000), pp. 262–263. 4. Raj Kumar, G. Achari, A. Mishra and D.K. Chhabra, Medulloblastomas of the cerebellopontine angle. Neurol. India 49 (2001), pp. 380–383. 5.Kadin Me and L.J. Rubinstein, Neonatal cerebellar medulloblastoma originating from the fetal external granular layer. J. Neuropathol. Exp. Neurol. 29 (1970), pp. 583–599. 6. Jaiswal AK, Mahapatra AK, Sharma MC. Cerebelloponitne angle medulloblastoma. J Clin Neurosci 2004;11:42-5 7. Ringertz N, Tola JH. Medulloblastomas. J Neuropathol Exp Neurol 1950;9:354-72. 8. Kumar R, Achari G, Mishra A, Chhabra DK. Medulloblastoma of cerebellopontine angle, 2001. Neurol India 49:380-3 9. Raaf J, Kernohan JW. Relation of abnormal collections of cells in posterior medullary velum of cerebellum to origin of medulloblastoma. Arch Neurol Psychiatry 1944;52:163-9. 10.  Kadin ME, Rubinstein LJ. Neonatal cerebellar medulloblastoma originating from fetal external granular layer. J Neuropathol Exp Neurol 1970;29:583-99.

PowerPoint Presentation: 

19 Thank you !