Difference between revisions of "Squamous cell carcinoma"

From Libre Pathology
Jump to navigation Jump to search
Line 31: Line 31:
*Keratinizing type (KT).
*Keratinizing type (KT).
**Worst prognosis.
**Worst prognosis.
**More common than non-keratinizing type.<ref>URL: [http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/LipOralCav_11protocol.pdf http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/LipOralCav_11protocol.pdf]. Accessed on: 3 April 2012.</ref>
*Undifferentiated type (UT).
*Undifferentiated type (UT).
**Intermediate prognosis.
**Intermediate prognosis.
**EBV association.
**EBV association.
*Nonkeratinizing type (NT).
*Non-keratinizing type (NT).
**Good prognosis.
**Good prognosis.
**EBV association.
**EBV association.

Revision as of 16:28, 3 April 2012

This article deal with squamous cell carcinoma, also squamous carcinoma, a very common epithelial derived malignant neoplasm that can arise from many sites. It is commonly abbreviated SCC.

Sites

Skin

Head and neck

Tumour extent

  • There is no agreed upon measure tumour extent (tumour thickness/depth of invasion)[1] - proposed measures:[2]
    • "Tumour thickness" = perpendicular distance from mucosal surface to deepest point of invasion.
    • "Tumour depth" = perpendicular distance epithelial basement membrane to deepest point of invasion.

Uterine cervix

Vulva

Lung

Other sites

Microscopic

Classification

SCC is subdivided by the WHO into:[3]

  • Keratinizing type (KT).
    • Worst prognosis.
    • More common than non-keratinizing type.[4]
  • Undifferentiated type (UT).
    • Intermediate prognosis.
    • EBV association.
  • Non-keratinizing type (NT).
    • Good prognosis.
    • EBV association.

Features based on classification:[3]

  • KT subtype:
    • Keratinization & intercellular bridges through-out most of the malignant lesion.
  • UT:
    • Non-distinct borders/syncytial pattern.
    • Nucleoli.
  • NT:
    • Well-defined cell borders.

Invasive squamous cell carcinoma

Features:

  • Eosinophilia.
  • Extra large nuclei/bizarre nuclei.
  • Inflammation (lymphocytes, plasma cells).
  • Long rete ridges.
  • Numerous beeds/blobs of epithelial cells that seem unlikely to be rete ridges.

Pitfalls:

  • Tangential cuts.
    • If you can trace the squamous cells from a gland to the surface it is less likely to be invasive cancer.

Notes on invasion:

Image(s):

Subtypes

There are several subtypes:[6]

  • Adenosquamous carcinoma.
  • Ancatholytic squamous cell carcinoma.
  • Basaloid squamous cell carcinoma - poor prognosis, usu. diagnosed by recognition of typical SCC.
  • Carcinoma cuniculatum.
  • Verrucous carcinoma - good prognosis, rare.
  • Papillary squamous cell carcinoma.
  • Lymphoepithelial carcinoma - rare.
  • Spindle cell squamous carcinoma - a common spindle cell lesion of the H&N.

Verrucous squamous cell carcinoma

  • AKA verrucous carcinoma.

General

  • Good prognosis.

Microscopic

Features:

  • Exophytic growth.
  • Well-differentiated.
  • "Glassy" appearance.
  • Pushing border - described "elephant feet".

DDx:

  • Papilloma.

Image:

Spindle cell squamous carcinoma

General

  • Common spindle cell lesion of the head and neck.

Microscopic

Feature:

  • Histomorphologic key to the diagnosis: finding a component of conventional squamous cell carcinoma.
  • Malignant spindle cell neoplasm.

DDx:

  • Spindle cell melanoma.
  • Mesenchymal neoplasm.

IHC

  • Typically keratin -ve.
  • p63 +ve.

Basaloid squamous cell carcinoma

Features:

  • Need keratinization. (???)

DDx:

  • Neuroendocrine tumour.

Lymphoepithelial (squamous cell) carcinoma

This is discussed in detail in the lymphoepithelioma-like carcinoma (LELC) article.
In the head and neck this is a separate entity known as nasopharyngeal carcinoma.

General

  • Rare.
  • +/-EBV.
  • Some consider this a distinct entity - rather than a subtype of SCC.[9]

Microscopic

Features:

  • Malignant squamoid cells (eosinophilic cytoplasm, nuclear atypia).
  • Abundant mononuclear inflammatory cells (plasma cells, lymphocytes).

Images: see the LELC article.

See also

References

  1. ↑ Pentenero, M.; Gandolfo, S.; Carrozzo, M. (Dec 2005). "Importance of tumor thickness and depth of invasion in nodal involvement and prognosis of oral squamous cell carcinoma: a review of the literature.". Head Neck 27 (12): 1080-91. doi:10.1002/hed.20275. PMID 16240329.
  2. ↑ URL: http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/LipOralCav_11protocol.pdf. Accessed on: 3 April 2012.
  3. ↑ 3.0 3.1 Mills, Stacey E; Carter, Darryl; Greenson, Joel K; Oberman, Harold A; Reuter, Victor E (2004). Sternberg's Diagnostic Surgical Pathology (4th ed.). Lippincott Williams & Wilkins. pp. 975. ISBN 978-0781740517.
  4. ↑ URL: http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/LipOralCav_11protocol.pdf. Accessed on: 3 April 2012.
  5. ↑ Wenig BM (March 2002). "Squamous cell carcinoma of the upper aerodigestive tract: precursors and problematic variants". Mod. Pathol. 15 (3): 229–54. doi:10.1038/modpathol.3880520. PMID 11904340. http://www.nature.com/modpathol/journal/v15/n3/pdf/3880520a.pdf.
  6. ↑ URL: http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/LipOralCav_11protocol.pdf. Accessed on: 3 April 2012.
  7. ↑ URL: http://www.juniordentist.com/verrucous-carcinoma.html. Accessed on: 3 April 2012.
  8. ↑ URL: http://www.biomedcentral.com/1471-2407/6/146. Accessed on: March 9, 2010.
  9. ↑ Skinner, NE.; Horowitz, RI.; Majmudar, B. (Oct 2000). "Lymphoepithelioma-like carcinoma of the uterine cervix.". South Med J 93 (10): 1024-7. PMID 11147469.
Retrieved from "https://librepathology.org/w/index.php?title=Squamous_cell_carcinoma&oldid=14551"