Difference between revisions of "Alveolar soft part sarcoma"
Jump to navigation
Jump to search
(more) |
(tweak some more) |
||
| Line 6: | Line 6: | ||
| Micro = large cells (~30-50 μm) with abundant eosinophilic cytoplasm and an eccentric nucleus +/-nucleolus, arranged in nest/separated by thin septa - vaguely resembles alveoli (at low power) | | Micro = large cells (~30-50 μm) with abundant eosinophilic cytoplasm and an eccentric nucleus +/-nucleolus, arranged in nest/separated by thin septa - vaguely resembles alveoli (at low power) | ||
| Subtypes = | | Subtypes = | ||
| LMDDx = [[alveolar rhabdomyosarcoma]] | | LMDDx = [[paraganglioma]], [[clear cell renal cell carcinoma]], [[alveolar rhabdomyosarcoma]] | ||
| Stains = PAS +ve (cytoplasm) | | Stains = PAS +ve (cytoplasm) | ||
| IHC = TFE3 +ve (suggestive of translocation) | | IHC = TFE3 +ve (suggestive of translocation) | ||
| EM = | | EM = intracytoplasmic crystal lattice with ~5 nm fibres spaced 10 nm apart | ||
| Molecular = t(X;17) | | Molecular = t(X;17) | ||
| IF = | | IF = | ||
| Line 17: | Line 17: | ||
| Assdx = | | Assdx = | ||
| Syndromes = | | Syndromes = | ||
| Clinicalhx = | | Clinicalhx = usu. slow growing mass | ||
| Signs = | | Signs = | ||
| Symptoms = | | Symptoms = | ||
| Prevalence = | | Prevalence = rare | ||
| Bloodwork = | | Bloodwork = | ||
| Rads = | | Rads = | ||
| Endoscopy = | | Endoscopy = | ||
| Prognosis = poor | | Prognosis = ultimately poor | ||
| Other = | | Other = | ||
| ClinDDx = | | ClinDDx = | ||
| Line 39: | Line 39: | ||
*Arranged in nest/separated by thin septa; vaguely resembles alveoli (at low power). | *Arranged in nest/separated by thin septa; vaguely resembles alveoli (at low power). | ||
*Large cells (~30-50 μm) with abundant eosinophilic cytoplasm. | *Large cells (~30-50 μm) with abundant eosinophilic cytoplasm. | ||
**May be focally cleared. | |||
*An eccentric nucleus. | *An eccentric nucleus. | ||
*+/-Nucleolus. | *+/-Nucleolus, prominent. | ||
*+/-Multi-nucleation (common). | |||
DDx: | DDx: | ||
*[[Rhabdomyosarcoma]], alveolar - usu. does not have sheets of rhabdoid cells. | *[[Paraganglioma]]. | ||
*[[Clear cell renal cell carcinoma]] - areas with cytoplasmic clearing. | |||
*[[Rhabdomyosarcoma]], alveolar - usu. does not have sheets of rhabdoid cells, no cross striations. | |||
===Images=== | ===Images=== | ||
| Line 68: | Line 72: | ||
*HMB45 -ve. | *HMB45 -ve. | ||
*Melan‐A -ve. | *Melan‐A -ve. | ||
*Chromogranin A -ve. | |||
*Synaptophysin -ve. | |||
==Molecular== | ==Molecular== | ||
Revision as of 03:48, 29 September 2013
| Alveolar soft part sarcoma | |
|---|---|
| Diagnosis in short | |
 ASPS. H&E stain. | |
|
| |
| LM | large cells (~30-50 μm) with abundant eosinophilic cytoplasm and an eccentric nucleus +/-nucleolus, arranged in nest/separated by thin septa - vaguely resembles alveoli (at low power) |
| LM DDx | paraganglioma, clear cell renal cell carcinoma, alveolar rhabdomyosarcoma |
| Stains | PAS +ve (cytoplasm) |
| IHC | TFE3 +ve (suggestive of translocation) |
| EM | intracytoplasmic crystal lattice with ~5 nm fibres spaced 10 nm apart |
| Molecular | t(X;17) |
| Site | soft tissue - usu. head and neck |
|
| |
| Clinical history | usu. slow growing mass |
| Prevalence | rare |
| Prognosis | ultimately poor |
Alveolar soft part sarcoma, abbreviated ASPS, is a rare malignant soft tissue lesion typically seen in younger individuals.
General
- Adolescents/young adults.
- Children -- classically location: base of tongue and orbit.
- Typical indolent initially - ultimately a poor prognosis.[1]
Microscopic
Features:[2]
- Arranged in nest/separated by thin septa; vaguely resembles alveoli (at low power).
- Large cells (~30-50 μm) with abundant eosinophilic cytoplasm.
- May be focally cleared.
- An eccentric nucleus.
- +/-Nucleolus, prominent.
- +/-Multi-nucleation (common).
DDx:
- Paraganglioma.
- Clear cell renal cell carcinoma - areas with cytoplasmic clearing.
- Rhabdomyosarcoma, alveolar - usu. does not have sheets of rhabdoid cells, no cross striations.
Images
ASPS - low mag. (WC/Nephron)
ASPS - intermed. mag. (WC/Nephron)
ASPS - very high mag. (WC/Nephron)
www:
Stains
- PAS +ve (cytoplasmic) - considered the most useful.[3]
- PASD +ve (cytoplasmic).
IHC
- TFE3 +ve -- suggestive of characteristic translocation.
- Desmin ~ 50% of cases.[1]
Others:[1]
- EMA -ve.
- Cytokeratins -ve.
- HMB45 -ve.
- Melan‐A -ve.
- Chromogranin A -ve.
- Synaptophysin -ve.
Molecular
- t(X;17)(p11.2;q25).[4]
Note:
- Same translocation may be seen in renal tumour with Xp11.2 translocation.
EM
- Distinctive membrane-bound intracytoplasmic crystal lattice with ~5 nm fibres spaced 10 nm apart.[1]
Image:
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Folpe, AL.; Deyrup, AT. (Nov 2006). "Alveolar soft-part sarcoma: a review and update.". J Clin Pathol 59 (11): 1127-32. doi:10.1136/jcp.2005.031120. PMC 1860509. PMID 17071801. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860509/.
- ↑ Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 627. ISBN 978-0781765275.
- ↑ Zarrin-Khameh, N.; Kaye, KS. (Mar 2007). "Alveolar soft part sarcoma.". Arch Pathol Lab Med 131 (3): 488-91. doi:10.1043/1543-2165(2007)131[488:ASPS]2.0.CO;2. PMID 17516754.
- ↑ Online 'Mendelian Inheritance in Man' (OMIM) 606243