Difference between revisions of "Small round cell tumours"
Jump to navigation
Jump to search
(more) |
|||
(32 intermediate revisions by the same user not shown) | |||
Line 1: | Line 1: | ||
[[Image:Ewing sarcoma - very high mag.jpg|thumb|right|[[Micrograph]] showing a small round cell tumour ([[Ewing sarcoma]]) in the lung. [[H&E stain]].]] | |||
'''Small round cell tumours''' (SRCT), also '''small round blue cell tumours''' (SRBCT), are a group of tumours that have a similar histologic appearance. | '''Small round cell tumours''' (SRCT), also '''small round blue cell tumours''' (SRBCT), are a group of tumours that have a similar histologic appearance. | ||
==General== | |||
*Group of tumours that is typically seen in childhood and younger adults. | |||
*Most common small round cell tumour is non-Hodgkin lymphoma.<ref name=pmid23998069/> | |||
DDx:<ref>URL: [http://www.thedoctorsdoctor.com/diseases/small_round_blue_cell_tumor.htm http://www.thedoctorsdoctor.com/diseases/small_round_blue_cell_tumor.htm]. Accessed on: 2 July 2010.</ref><ref>{{cite journal |author=Chen QR, Vansant G, Oades K, ''et al.'' |title=Diagnosis of the small round blue cell tumors using multiplex polymerase chain reaction |journal=J Mol Diagn |volume=9 |issue=1 |pages=80–8 |year=2007 |month=February |pmid=17251339 |pmc=1867426 |doi=10.2353/jmoldx.2007.060111 |url=}}</ref> | ===A short differential diagnosis of small round cell tumours=== | ||
A short DDx of SRCTs:<ref>URL: [http://www.thedoctorsdoctor.com/diseases/small_round_blue_cell_tumor.htm http://www.thedoctorsdoctor.com/diseases/small_round_blue_cell_tumor.htm]. Accessed on: 2 July 2010.</ref><ref>{{cite journal |author=Chen QR, Vansant G, Oades K, ''et al.'' |title=Diagnosis of the small round blue cell tumors using multiplex polymerase chain reaction |journal=J Mol Diagn |volume=9 |issue=1 |pages=80–8 |year=2007 |month=February |pmid=17251339 |pmc=1867426 |doi=10.2353/jmoldx.2007.060111 |url=}}</ref> | |||
*[[Neuroblastoma]]. | *[[Neuroblastoma]]. | ||
*[[Wilms tumour]] ([[AKA]] nephroblastoma). | *[[Wilms tumour]] ([[AKA]] nephroblastoma). | ||
Line 12: | Line 16: | ||
*[[Liver neoplasms|Hepatoblastoma]]. | *[[Liver neoplasms|Hepatoblastoma]]. | ||
*[[Desmoplastic small round cell tumour]] (DSRCT). | *[[Desmoplastic small round cell tumour]] (DSRCT). | ||
*Small cell carcinoma. | *[[Small cell carcinoma]]. | ||
Others: | Others: | ||
*Small cell | *[[Small cell osteosarcoma]]. | ||
*[[Synovial sarcoma]]. | *[[Synovial sarcoma]]. | ||
Memory device: 4 -blastomas (hepato-, neuro-, nephro-, retino-), PNET/Ewing sarcoma (medulloblastoma), LADSSS (lymphoma, alveolar rhabdomyosarcoma, DSRCT, small cell carcinoma, small cell osteosarcoma, synovial sarcoma). | Memory device: 4 -blastomas (hepato-, neuro-, nephro-, retino-), PNET/Ewing sarcoma (medulloblastoma), LADSSS (lymphoma, alveolar rhabdomyosarcoma, DSRCT, small cell carcinoma, small cell osteosarcoma, synovial sarcoma). | ||
===A long differential diagnosis of small blue cell tumours=== | |||
Adapted from ''Miller'' with modifications:<ref name=miller>Miller RT. (Sep 2013). ''Atlantic Diagnostic Immunohistochemistry Symposium''. St. John's, NL, Canada.</ref> | |||
{| class="wikitable sortable" | |||
! Tumour | |||
! Group | |||
! Notes/comments | |||
|- | |||
| [[Malignant melanoma]], small cell | |||
| melanoma | |||
| | |||
|- | |||
| [[PEComa]] | |||
| mesenchymal lesion | |||
| | |||
|- | |||
| Carcinoma not otherwise specified | |||
| carcinoma | |||
| | |||
|- | |||
| [[Small cell carcinoma]] | |||
| carcinoma | |||
| | |||
|- | |||
| [[Merkel cell carcinoma]] | |||
| carcinoma | |||
| | |||
|- | |||
| [[Islet cell tumour]] ([[carcinoid]]) | |||
| carcinoma | |||
| | |||
|- | |||
| [[Medullary thyroid carcinoma]] | |||
| carcinoma | |||
| | |||
|- | |||
| [[Desmoplastic small round cell tumour]] | |||
| sarcoma | |||
| | |||
|- | |||
| [[Polyphenotypic small cell tumour]] | |||
| other | |||
| | |||
|- | |||
| [[Papillary-cystic tumour of pancreas]] | |||
| other | |||
| | |||
|- | |||
| [[Pancreatoblastoma]] | |||
| other | |||
| | |||
|- | |||
| [[Acinar cell carcinoma]] | |||
| carcinoma | |||
| | |||
|- | |||
| [[Adenoid cystic carcinoma]] | |||
| carcinoma | |||
| | |||
|- | |||
| Cutaneous adnexal tumours ([[spiradenoma]], [[acrospiroma]]) | |||
| other | |||
| | |||
|- | |||
| [[Wilms tumour]] | |||
| other | |||
| | |||
|- | |||
| [[Thymoma]] | |||
| epithelial lesion | |||
| | |||
|- | |||
| [[Metanephric adenoma|Metanephric adenoma of urinary tract]] | |||
| epithelial lesion | |||
| | |||
|- | |||
| Basaloid carcinoma / [[Basal cell carcinoma]] | |||
| carcinoma | |||
| | |||
|- | |||
| [[Small cell mesothelioma]] | |||
| carcinoma | |||
| <ref name=pmid1310669>{{Cite journal | last1 = Mayall | first1 = FG. | last2 = Gibbs | first2 = AR. | title = The histology and immunohistochemistry of small cell mesothelioma. | journal = Histopathology | volume = 20 | issue = 1 | pages = 47-51 | month = Jan | year = 1992 | doi = | PMID = 1310669 }}</ref> | |||
|- | |||
| [[Pulmonary blastoma]] | |||
| other | |||
| | |||
|- | |||
| [[Cutaneous myoepithelioma]] | |||
| epithelial lesion | |||
|<ref>{{Cite journal | last1 = Kutzner| first1 = H.| last2 = Mentzel| first2 = T.| last3 = Kaddu| first3 = S.| last4 = Soares| first4 = LM.| last5 = Sangueza| first5 = OP.| last6 = Requena| first6 = L.| title = Cutaneous myoepithelioma: an under-recognized cutaneous neoplasm composed of myoepithelial cells.| journal = Am J Surg Pathol| volume = 25| issue = 3| pages = 348-55| month = Mar| year = 2001| doi = | PMID = 11224605 }}</ref> | |||
|- | |||
| [[Ewing sarcoma]] / [[PNET]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Neuroblastoma]] / [[esthesioneuroblastoma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Sclerosing perineurioma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Schwannoma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Meningioma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Medulloblastoma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Central neurocytoma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Medulloepithelioma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Retinoblastoma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Oligodendroglioma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Pineocytoma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Hemangioblastoma]] | |||
| neural tumours | |||
| may be seen extraneural | |||
|- | |||
| [[Neurogenic sarcoma]] | |||
| neural tumours | |||
| | |||
|- | |||
| [[Lymphoma]] | |||
| lymphoid | |||
| | |||
|- | |||
| [[Extramedullary leukemia]] | |||
| lymphoid | |||
| | |||
|- | |||
| [[Plasma cell myeloma]] | |||
| lymphoid | |||
| | |||
|- | |||
| [[Mastocytosis]] | |||
| lymphoid | |||
| | |||
|- | |||
| [[Plasmacytoid dendritic cell tumour]] | |||
| lymphoid | |||
|CD4 +ve, CD56 +ve<ref name=pmid16160468>{{Cite journal | last1 = Reichard| first1 = KK.| last2 = Burks| first2 = EJ.| last3 = Foucar| first3 = MK.| last4 = Wilson| first4 = CS.| last5 = Viswanatha| first5 = DS.| last6 = Hozier| first6 = JC.| last7 = Larson| first7 = RS.| title = CD4(+) CD56(+) lineage-negative malignancies are rare tumors of plasmacytoid dendritic cells.| journal = Am J Surg Pathol| volume = 29| issue = 10| pages = 1274-83| month = Oct| year = 2005| doi = | PMID = 16160468 }}</ref> | |||
|- | |||
| [[Granuloma annulare]] | |||
| histiocytic lesion | |||
| | |||
|- | |||
| [[Seminoma]] | |||
| germ cell tumour | |||
| degenerative cases | |||
|- | |||
| [[Granulosa cell tumour]] | |||
| sex cord tumour | |||
| | |||
|- | |||
| [[Gynandroblastoma]] | |||
| sex cord tumour | |||
| Sertoli cell & granulosa cell | |||
|- | |||
| [[Sertoli-Leydig tumour]] | |||
| sex cord tumour | |||
| | |||
|- | |||
| [[Endometrial stromal sarcoma]] | |||
| sarcoma | |||
| may be extragenital | |||
|- | |||
| [[Adenosarcoma]] | |||
| sarcoma | |||
| glandular component may not be sampled | |||
|- | |||
| [[Rhabdomyosarcoma]] | |||
| muscle | |||
| | |||
|- | |||
| Skeletal muscle regeneration | |||
| muscle | |||
| mimics [[rhabdomyosarcoma]]<ref name=pmid9762546>{{Cite journal | last1 = Guillou| first1 = L.| last2 = Coquet| first2 = M.| last3 = Chaubert| first3 = P.| last4 = Coindre| first4 = JM.| title = Skeletal muscle regeneration mimicking rhabdomyosarcoma: a potential diagnostic pitfall.| journal = Histopathology| volume = 33| issue = 2| pages = 136-44| month = Aug| year = 1998| doi = | PMID = 9762546 }}</ref> | |||
|- | |||
| [[Small cell leiomyosarcoma]] | |||
| sarcoma | |||
| | |||
|- | |||
| [[Small cell osteosarcoma]] | |||
| chondro-osseous tumours | |||
| | |||
|- | |||
| [[Mesenchymal chondrosarcoma]] | |||
| chondro-osseous tumours | |||
| | |||
|- | |||
| [[Myxoid chondrosarcoma]] | |||
| chondro-osseous tumours | |||
| | |||
|- | |||
| [[Proliferative myositis]] | |||
| muscle | |||
| | |||
|- | |||
| [[Fetal or genital rhabdomyoma]] | |||
| other | |||
| | |||
|- | |||
| [[Glomus tumour]] | |||
| other | |||
| | |||
|- | |||
| [[Glomangiopericytoma]] | |||
| other | |||
| | |||
|- | |||
| [[Synovial sarcoma]] | |||
| sarcoma | |||
| | |||
|- | |||
| [[Hemangiopericytoma]] | |||
| soft tissue lesions | |||
| | |||
|- | |||
| [[angiosarcoma|Small cell angiosarcoma]] | |||
| vascular lesions | |||
| | |||
|- | |||
| [[Epithelioid hemangioendothelioma]] | |||
| vascular lesions | |||
| | |||
|- | |||
| [[Solitary fibrous tumour]] | |||
| soft tissue lesions | |||
| can be myxoid | |||
|- | |||
| [[Myofibroblastoma]] | |||
| soft tissue lesions | |||
| | |||
|- | |||
| [[Angiomyofibroblastoma]] | |||
| soft tissue lesions | |||
| | |||
|- | |||
|} | |||
Notes: | |||
#This [[DDx]] includes small cells that may be spindled. | |||
#The DDx for large (non-pleomorphic) epithelioid cells is found in ''[[large epithelioid tumours]]''. | |||
==Microscopic== | ==Microscopic== | ||
Features: | Features: | ||
*Small cells ~ 2X [[RBC]] diameter - '''key feature'''. | *Small cells ~ 2X [[RBC]] diameter - '''key feature'''. | ||
*Scant cytoplasm/high NC ratio. | *Scant cytoplasm/high [[NC ratio]]. | ||
*Sheets of cells, very cellular. | *Sheets of cells, very cellular. | ||
*Coarse chromatin. | *Coarse chromatin. | ||
Line 31: | Line 299: | ||
==Tabular comparison== | ==Tabular comparison== | ||
Adapted from Thorner:<ref>PST. 14 February 2011.</ref> | Adapted from Thorner:<ref>PST. 14 February 2011.</ref> | ||
{| class="wikitable" | {| class="wikitable sortable" | ||
! '''Tumour''' | |||
! '''Key histologic features''' | |||
! '''History''' | |||
! '''Key [[IHC]] / <br>special stains''' | |||
|- | |- | ||
| [[Hepatoblastoma]] | | [[Hepatoblastoma]] | ||
Line 45: | Line 313: | ||
| nests, thin fibrovascular septae, lymphocytes, ganglion-like cells (prominent nucleolus), neuropil (eosinophilic, fluffy, finely vacuolated) | | nests, thin fibrovascular septae, lymphocytes, ganglion-like cells (prominent nucleolus), neuropil (eosinophilic, fluffy, finely vacuolated) | ||
| adrenal gland, sympathetic chain; usu. < 3 years old | | adrenal gland, sympathetic chain; usu. < 3 years old | ||
| NB-84+, NSE+, | | NB-84+, NSE+, [[S-100]]- | ||
|- | |- | ||
| [[Nephroblastoma]] (Wilms tumour) | | [[Nephroblastoma]] (Wilms tumour) | ||
Line 80: | Line 348: | ||
| '''nests with "jigsaw" border''' | | '''nests with "jigsaw" border''' | ||
| peritoneum (abdomen or plevis); male > female; locally invasive | | peritoneum (abdomen or plevis); male > female; locally invasive | ||
| keratin+, EMA+, desmin+ !!! | | [[keratin]]+, [[EMA]]+, desmin+ !!! | ||
|- | |- | ||
| Small cell carcinoma | | [[Small cell carcinoma]] | ||
| '''nuclear moulding''', stippled chromatin | | '''nuclear moulding''', stippled chromatin | ||
| adults, smokers | | adults, smokers | ||
| synaptophysin, chromogranin, CD56, keratins | | synaptophysin, chromogranin A, CD56, keratins | ||
|- | |- | ||
| [[Lymphoma]], non-Hogkin's, usu. large cell (e.g. [[DLBCL]]) | | [[Lymphoma]], non-Hogkin's, usu. large cell (e.g. [[DLBCL]]) | ||
| '''dyscohesive cells''', usu. ~2x normal (resting) lymphocyte, usu. nucleolus | | '''dyscohesive cells''', usu. ~2x normal (resting) lymphocyte, usu. nucleolus | ||
| usu. lymphadenopathy | | usu. lymphadenopathy | ||
| CD45 | | CD45, [[CD20]], TdT, [[CD3]] | ||
|- | |- | ||
|} | |} | ||
Line 97: | Line 365: | ||
==IHC panel== | ==IHC panel== | ||
Gino's panel:<ref> | Gino's panel:<ref>G. Somers. 22 March 2011.</ref> | ||
{| class="wikitable sortable" style="margin-left:auto;margin-right:auto" | {| class="wikitable sortable" style="margin-left:auto;margin-right:auto" | ||
! Lesion | ! Lesion | ||
Line 134: | Line 402: | ||
| -ve | | -ve | ||
|} | |} | ||
More general panel:<ref name=pmid23998069>{{Cite journal | last1 = D'cruze | first1 = L. | last2 = Dutta | first2 = R. | last3 = Rao | first3 = S. | last4 = R | first4 = A. | last5 = Varadarajan | first5 = S. | last6 = Kuruvilla | first6 = S. | title = The role of immunohistochemistry in the analysis of the spectrum of small round cell tumours at a tertiary care centre. | journal = J Clin Diagn Res | volume = 7 | issue = 7 | pages = 1377-82 | month = Jul | year = 2013 | doi = 10.7860/JCDR/2013/5127.3132 | PMID = 23998069 }}</ref> | |||
*CD45, CD20, CD3, CD99, desmin, EMA, pankeratin, synaptophysin, chromogranin, GFAP. | |||
==See also== | ==See also== | ||
*[[Soft tissue lesions]]. | *[[Soft tissue lesions]]. | ||
*[[Basics]]. | |||
*[[Large epithelioid tumours]]. | |||
*[[Pleomorphic tumours]]. | |||
==References== | ==References== | ||
Line 142: | Line 416: | ||
[[Category:Weird stuff]] | [[Category:Weird stuff]] | ||
[[Category:Pediatric pathology]] |
Latest revision as of 15:50, 5 March 2017
Small round cell tumours (SRCT), also small round blue cell tumours (SRBCT), are a group of tumours that have a similar histologic appearance.
General
- Group of tumours that is typically seen in childhood and younger adults.
- Most common small round cell tumour is non-Hodgkin lymphoma.[1]
A short differential diagnosis of small round cell tumours
- Neuroblastoma.
- Wilms tumour (AKA nephroblastoma).
- Alveolar rhabdomyosarcoma.
- Ewing sarcoma / primative neuroectodermal tumour (PNET).
- Lymphoma - non-Hogkin's lymphoma, usu. large cell lymphomas (e.g. diffuse large B cell lymphoma, anaplastic large cell lymphoma), Burkitt's lymphoma.
- Retinoblastoma.
- Hepatoblastoma.
- Desmoplastic small round cell tumour (DSRCT).
- Small cell carcinoma.
Others:
Memory device: 4 -blastomas (hepato-, neuro-, nephro-, retino-), PNET/Ewing sarcoma (medulloblastoma), LADSSS (lymphoma, alveolar rhabdomyosarcoma, DSRCT, small cell carcinoma, small cell osteosarcoma, synovial sarcoma).
A long differential diagnosis of small blue cell tumours
Adapted from Miller with modifications:[4]
Notes:
- This DDx includes small cells that may be spindled.
- The DDx for large (non-pleomorphic) epithelioid cells is found in large epithelioid tumours.
Microscopic
Features:
- Small cells ~ 2X RBC diameter - key feature.
- Scant cytoplasm/high NC ratio.
- Sheets of cells, very cellular.
- Coarse chromatin.
- +/-Nucleolus; usu. not prominent.
- +/-Vascularity.
Tabular comparison
Adapted from Thorner:[9]
Tumour | Key histologic features | History | Key IHC / special stains |
---|---|---|---|
Hepatoblastoma | fetal hepatocytes (~ 1:3 NC ratio, eosinophilic cytoplasm) | liver lesion, usu. < 3 years old | AFP |
Neuroblastoma | nests, thin fibrovascular septae, lymphocytes, ganglion-like cells (prominent nucleolus), neuropil (eosinophilic, fluffy, finely vacuolated) | adrenal gland, sympathetic chain; usu. < 3 years old | NB-84+, NSE+, S-100- |
Nephroblastoma (Wilms tumour) | triphasic - (1) blue cells (blastema), (2) spindle cells (stroma), (3) tubular structures (epithelial) | kidney lesion, various syndromes (e.g. Beckwith-Wiedemann syndrome[10]) | WT-1+ |
Retinoblastoma | Flexner-Wintersteiner rosette (rosette with empty centre (donut hole))[11] | eye lesion; +/-RB1 gene mutations (familial) | |
Medulloblastoma | Homer-Wright rosettes (rosette with a meshwork of fibers (neuropil) at the centre)[11] | +/-nevoid basal cell carcinoma syndrome; must arise in cerebellum | |
Ewing sarcoma/PNET | clear cytoplasm (glycogen) | bone lesion, adolescents | PAS+/PASD-, CD99 diffuse membranous |
Alveolar rhabdomyosarcoma | alveolar-like spaces (small blue cells line spaces supported by fibrous tissue), rhabdomyoblasts (eosinophilic cytoplasm, +/-cross striations (uncommon), eccentric nucleus, +/-elongated/cigar-shaped cells (uncommon)) | adolescents, young adults; often mets at presentation | "DAM" = desmin, actin, myogenin |
Embryonal rhabdomyosarcoma§ | nests with rounded border, rhabdomyoblasts (+/-elongated/cigar-shaped cells, eosinophilic cytoplasm, +/-cross striations, eccentric nucleus) | <10 years old; usu. localized | "DAM" = desmin, actin, myogenin |
Desmoplastic small round cell tumour (DSRCT) | nests with "jigsaw" border | peritoneum (abdomen or plevis); male > female; locally invasive | keratin+, EMA+, desmin+ !!! |
Small cell carcinoma | nuclear moulding, stippled chromatin | adults, smokers | synaptophysin, chromogranin A, CD56, keratins |
Lymphoma, non-Hogkin's, usu. large cell (e.g. DLBCL) | dyscohesive cells, usu. ~2x normal (resting) lymphocyte, usu. nucleolus | usu. lymphadenopathy | CD45, CD20, TdT, CD3 |
Notes:
- § Uncommonly has the small round cell tumour morphology - included for comparison to alveolar rhabdomyosarcoma.
IHC panel
Gino's panel:[12]
Lesion | NB84 | Myogenin | Desmin | CD99 | CD45 |
---|---|---|---|---|---|
Lymphoma | -ve | -ve | -ve | +ve/-ve | + |
Ewing sarcoma | +ve/-ve | -ve | -ve | +ve (membranous) | - |
Neuroblastoma | +ve | -ve | -ve | +ve/-ve | -ve |
Rhabdomyosarcoma | -ve | +ve | +ve | -ve | -ve |
More general panel:[1]
- CD45, CD20, CD3, CD99, desmin, EMA, pankeratin, synaptophysin, chromogranin, GFAP.
See also
References
- ↑ 1.0 1.1 D'cruze, L.; Dutta, R.; Rao, S.; R, A.; Varadarajan, S.; Kuruvilla, S. (Jul 2013). "The role of immunohistochemistry in the analysis of the spectrum of small round cell tumours at a tertiary care centre.". J Clin Diagn Res 7 (7): 1377-82. doi:10.7860/JCDR/2013/5127.3132. PMID 23998069.
- ↑ URL: http://www.thedoctorsdoctor.com/diseases/small_round_blue_cell_tumor.htm. Accessed on: 2 July 2010.
- ↑ Chen QR, Vansant G, Oades K, et al. (February 2007). "Diagnosis of the small round blue cell tumors using multiplex polymerase chain reaction". J Mol Diagn 9 (1): 80–8. doi:10.2353/jmoldx.2007.060111. PMC 1867426. PMID 17251339. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1867426/.
- ↑ Miller RT. (Sep 2013). Atlantic Diagnostic Immunohistochemistry Symposium. St. John's, NL, Canada.
- ↑ Mayall, FG.; Gibbs, AR. (Jan 1992). "The histology and immunohistochemistry of small cell mesothelioma.". Histopathology 20 (1): 47-51. PMID 1310669.
- ↑ Kutzner, H.; Mentzel, T.; Kaddu, S.; Soares, LM.; Sangueza, OP.; Requena, L. (Mar 2001). "Cutaneous myoepithelioma: an under-recognized cutaneous neoplasm composed of myoepithelial cells.". Am J Surg Pathol 25 (3): 348-55. PMID 11224605.
- ↑ Reichard, KK.; Burks, EJ.; Foucar, MK.; Wilson, CS.; Viswanatha, DS.; Hozier, JC.; Larson, RS. (Oct 2005). "CD4(+) CD56(+) lineage-negative malignancies are rare tumors of plasmacytoid dendritic cells.". Am J Surg Pathol 29 (10): 1274-83. PMID 16160468.
- ↑ Guillou, L.; Coquet, M.; Chaubert, P.; Coindre, JM. (Aug 1998). "Skeletal muscle regeneration mimicking rhabdomyosarcoma: a potential diagnostic pitfall.". Histopathology 33 (2): 136-44. PMID 9762546.
- ↑ PST. 14 February 2011.
- ↑ URL: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002168/. Accessed on: 4 April 2011.
- ↑ 11.0 11.1 Wippold FJ, Perry A (March 2006). "Neuropathology for the neuroradiologist: rosettes and pseudorosettes". AJNR Am J Neuroradiol 27 (3): 488–92. PMID 16551982.
- ↑ G. Somers. 22 March 2011.