Difference between revisions of "Lipomatous tumor"

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File:Histopathology of a fibrolipoma.jpg|'''Fibrolipoma''' is a lipoma with focal areas of large amounts of fibrous tissue.<br>A '''sclerotic lipoma''' is one step further: a predominantly fibrous lesion with focal areas of fat.<ref>{{cite web|url=http://surgpathcriteria.stanford.edu/softfat/lipoma/fibrolipoma.html|title=Lipoma Variant: Fibrolipoma|website=Stanford University School of Medicine|accessdate=2020-02-10}}</ref><br>If unsure of degree of fibrosis: Simply report as lipoma.
 
File:Histopathology of a fibrolipoma.jpg|'''Fibrolipoma''' is a lipoma with focal areas of large amounts of fibrous tissue.<br>A '''sclerotic lipoma''' is one step further: a predominantly fibrous lesion with focal areas of fat.<ref>{{cite web|url=http://surgpathcriteria.stanford.edu/softfat/lipoma/fibrolipoma.html|title=Lipoma Variant: Fibrolipoma|website=Stanford University School of Medicine|accessdate=2020-02-10}}</ref><br>If unsure of degree of fibrosis: Simply report as lipoma.
 
File:Histopathology of angiolipoma.jpg|'''Angiolipoma''' is a lipoma with abundant capillaries, with hyaline or fibrin (pictured) thrombi.<ref>{{cite web|url=http://www.pathologyoutlines.com/topic/softtissueadiposeangiolipoma.html|title=Soft tissue - Adipose tissue tumors - Lipoma and variants - Angiolipoma|author=Vijay Shankar|website=Pathology Outlines}} Topic Completed: 1 August 2012. Minor changes: 20 March 2019</ref>
 
File:Histopathology of angiolipoma.jpg|'''Angiolipoma''' is a lipoma with abundant capillaries, with hyaline or fibrin (pictured) thrombi.<ref>{{cite web|url=http://www.pathologyoutlines.com/topic/softtissueadiposeangiolipoma.html|title=Soft tissue - Adipose tissue tumors - Lipoma and variants - Angiolipoma|author=Vijay Shankar|website=Pathology Outlines}} Topic Completed: 1 August 2012. Minor changes: 20 March 2019</ref>
 +
File:Histopathology of an atypical lipomatous tumor or well-differentiated liposarcoma, lipoma-like subtype.jpg|Histopathology of an '''atypical lipomatous tumor''' (also termed '''well-differentiated liposarcoma'''), lipoma-like subtype. At low magnification, the majority of the tumor has the look of benign mature adipocytes, but a high magnification of a fibrous band shows spindle cells with enlarged, hyperchromatic nuclei.
 
File:Histopathology of liposarcoma, annotated.jpg|Main features of '''liposarcoma''':<ref name=PathologyOutlines>{{cite web|url=https://www.pathologyoutlines.com/topic/softtissuewdliposarcoma.html%7Ctitle=Liposarcoma|author=Michael R. Clay, M.D.|website=PathologyOutlines|title=Liposarcoma}} Topic Completed: 1 November 2017. Minor changes: 11 May 2021</ref><br>- Spindle cells with enlarged, hyperchromatic nuclei.<br>- Apparently univacuolated adipocytes (may look normal).<br>- [[Lipoblast]]s (multivacuolated), but neither necessary nor sufficient for diagnosis.
 
File:Histopathology of liposarcoma, annotated.jpg|Main features of '''liposarcoma''':<ref name=PathologyOutlines>{{cite web|url=https://www.pathologyoutlines.com/topic/softtissuewdliposarcoma.html%7Ctitle=Liposarcoma|author=Michael R. Clay, M.D.|website=PathologyOutlines|title=Liposarcoma}} Topic Completed: 1 November 2017. Minor changes: 11 May 2021</ref><br>- Spindle cells with enlarged, hyperchromatic nuclei.<br>- Apparently univacuolated adipocytes (may look normal).<br>- [[Lipoblast]]s (multivacuolated), but neither necessary nor sufficient for diagnosis.
 
File:Myxoid liposarcoma (16105753363).jpg|'''Myxoid liposarcoma''': Hypercellular solid sheets of cells lying back to back, with round cells or primitive cytomorphology.<ref>{{cite web|url=http://www.pathologyoutlines.com/topic/softtissuemyxoidliposarcoma.html|title=Soft tissue - Adipose tissue - Myxoid liposarcoma|author=Michael R. Clay|website=PathologyOutlines}} Topic Completed: 1 January 2018. Revised: 20 March 2019</ref>
 
File:Myxoid liposarcoma (16105753363).jpg|'''Myxoid liposarcoma''': Hypercellular solid sheets of cells lying back to back, with round cells or primitive cytomorphology.<ref>{{cite web|url=http://www.pathologyoutlines.com/topic/softtissuemyxoidliposarcoma.html|title=Soft tissue - Adipose tissue - Myxoid liposarcoma|author=Michael R. Clay|website=PathologyOutlines}} Topic Completed: 1 January 2018. Revised: 20 March 2019</ref>

Revision as of 17:54, 20 May 2021

Author: Mikael Häggström [note 1]

Lipomatous tumor.

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation


Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Gross processing

  • Perform consecutive slicing of the entire specimen.
  • Look for signs of liposarcoma: Mainly by firm volumes.[1] Color varies from yellow to white (and firm) depending on the proportion of adipocytic, fibrous and/or myxoid content.[2] Areas of fat necrosis are common in larger lesions. Rarely, infiltrative growth is seen.[2]
  • Submit slices from any suspicious parts, or at least one representative slice from the specimen.[3] (A more comprehensive practice is to submit 1 section per centimeter, and 2 sections per cassette.[4])

Gross report

  • Color
  • Even absence of hemorrhage or necrosis.

Example:

Mass ((weighing 121 grams)) and measuring 10 x 6,5 x 3,5 cm. ((The surgical margin is intact.)) Cut sections show homogenous yellow color, with no hemorrhage or necrosis. ((The specimen is serially sectioned, and representative sections are submitted for microscopic examination in __ cassettes.))

  See also: General notes on gross processing


Microscopic evaluation

A pedunculated lipomatous skin tumor may be a pedunculated lipofibroma:

Microscopy/Histopathology report

For lipomas: Absence of signs of malignancy.

Histopathology of lipoma.jpg

((Tissue composed of univacuolar fat cells and delicate and inconspicuous fibrous septa.)) No evidence of malignancy.
-Lipoma.

  See also: General notes on reporting


Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Monica Dahlgren, Janne Malina, Anna Måsbäck, Otto Ljungberg (1997-02-13). Lilla utskärningen.
  2. 2.0 2.1 Andreas F Mavrogenis, Panayiotis J Papagelopoulos (2013-02-01). Soft Tissues: Well-differentiated liposarcoma. Atlas of Genetics and Cytogenetics in Oncology and Haematology.
  3. Pathology Department at NU Hospital Group, Sweden, 2019-2020.
  4. . Lipoma. Gross Pathology Manual - By The University of Chicago Department of Pathology. Retrieved on 2020-08-26.
  5. . Lipoma Variant: Fibrolipoma. Stanford University School of Medicine. Retrieved on 2020-02-10.
  6. Vijay Shankar. Soft tissue - Adipose tissue tumors - Lipoma and variants - Angiolipoma. Pathology Outlines. Topic Completed: 1 August 2012. Minor changes: 20 March 2019
  7. Michael R. Clay, M.D.. Liposarcoma. PathologyOutlines. Topic Completed: 1 November 2017. Minor changes: 11 May 2021
  8. Michael R. Clay. Soft tissue - Adipose tissue - Myxoid liposarcoma. PathologyOutlines. Topic Completed: 1 January 2018. Revised: 20 March 2019

Image sources