Rhabdomyosarcoma pathophysiology: Difference between revisions
(Mahshid) |
No edit summary |
||
Line 5: | Line 5: | ||
Rhabdomyosarcoma arises from the skeletal muscle cells. Development of alveolar rhabdomyosarcoma is result of specific [[genetic mutations]]. The pathogenesis of rhabdomyosarcoma include t(2;13) and t(1;13) [[Chromosomal translocation|chromosomal translocations]]. The microscopic pathology of rhabdomyosarcoma depends on the histological subtype. | Rhabdomyosarcoma arises from the skeletal muscle cells. Development of alveolar rhabdomyosarcoma is result of specific [[genetic mutations]]. The pathogenesis of rhabdomyosarcoma include t(2;13) and t(1;13) [[Chromosomal translocation|chromosomal translocations]]. The microscopic pathology of rhabdomyosarcoma depends on the histological subtype. | ||
==Pathophysiology== | ===Pathophysiology=== | ||
==Histology== | |||
* The origin of rhabdomyosarcoma is muscle cells. | |||
* The presentation sites of rhabdomyosarcoma are: | |||
** Head and neck (28%) | |||
** Extremities (24%) | |||
** Genitourinary tract (18%) | |||
** Trunk (11%) | |||
**Orbit (7%) | |||
**Retroperitoneum (6%) | |||
**Other sites such as bladder, vagina, nasopharynx, and middle ear (3%) | |||
===Genetics=== | ===Genetics=== | ||
====Alveolar rhabdomyosarcoma==== | ====Alveolar rhabdomyosarcoma==== |
Revision as of 21:03, 21 January 2019
Rhabdomyosarcoma Microchapters |
Diagnosis |
---|
Treatment |
Case Studies |
Rhabdomyosarcoma pathophysiology On the Web |
American Roentgen Ray Society Images of Rhabdomyosarcoma pathophysiology |
Risk calculators and risk factors for Rhabdomyosarcoma pathophysiology |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Suveenkrishna Pothuru, M.B,B.S. [2]
Overview
Rhabdomyosarcoma arises from the skeletal muscle cells. Development of alveolar rhabdomyosarcoma is result of specific genetic mutations. The pathogenesis of rhabdomyosarcoma include t(2;13) and t(1;13) chromosomal translocations. The microscopic pathology of rhabdomyosarcoma depends on the histological subtype.
Pathophysiology
Histology
- The origin of rhabdomyosarcoma is muscle cells.
- The presentation sites of rhabdomyosarcoma are:
- Head and neck (28%)
- Extremities (24%)
- Genitourinary tract (18%)
- Trunk (11%)
- Orbit (7%)
- Retroperitoneum (6%)
- Other sites such as bladder, vagina, nasopharynx, and middle ear (3%)
Genetics
Alveolar rhabdomyosarcoma
Specific genetic abnormalities have been identified, that are specific for alveolar rhabdomyosarcomas. They include t(2;13) and t(1;13) chromosomal translocations resulting in PAX3-FKHR and PAX7-FKHR gene fusions.
Microscopic Pathology
Characteristic features on microscopic analysis are variable depending on the rhabdomyosarcoma subtype:[1]
Alveolar Rhabdomyosarcoma
- Characterized by Alveolus-like pattern.
- Fibrous septae lined by tumor cells.
- Cells may "fall-off" the septa, i.e. be detached/scattered in the alveolus-like space.
- Space between fibrous septae may be filled with tumor, called solid variant of alveolar rhabdomyosarcoma.
- Rhabdomyoblasts: Essentially diagnostic cells with eccentric nucleus and moderate amount of intensely eosinophilic cytoplasm.
- Nuclear pleomorphism
- Mitoses
Embryonal Rhabdomyosarcoma
- Randomly arranged small cells
- Myxoid matrix
- Strap cells: Tadpole like morphology
- Rhabdomyoblasts: Essentially diagnostic cells with eccentric nucleus and moderate amount of intensely eosinophilic cytoplasm
Botryoid Rhabdomyosarcoma
- Malignant cells in an abundant myxoid stroma.
- Non-proliferating layer deep to the surface called "Cambium layer".
- Cambium layer is defined as cellular region deep to epithelial component.
Spindlecell Rhabdomyosarcoma
- Vesicular growth pattern
- Spindle cells