Difference between revisions of "Carcinoma ex pleomorphic adenoma"

Carcinoma ex pleomorphic adenoma
	Diagnosis in short
	; Carcinoma ex pleomorphic adenoma. H&E stain.
LM	epithelial or myoepithelial cells with cytologic features of malignancy, pleomorphic adenoma (required if no history)
LM DDx	salivary duct carcinoma, mucoepidermoid carcinoma, adenoid cystic carcinoma, pleomorphic adenoma
Gross	firm
Site	salivary gland - usu. parotid gland
Clinical history	pleomorphic adenoma (required if not present in assoc. with carcinoma)
Signs	usu. mass lesion, firm
Prevalence	uncommon
Prognosis	dependent on stage, typically poor

Latest revision as of 01:42, 26 December 2014

Carcinoma ex pleomorphic adenoma, abbreviated ca ex PA, is a rare malignant salivary gland tumour that arises from a pleomorphic adenoma.

General

Definition:

Malignancy arising from a pleomorphic adenoma.^[1]

Diagnosis (either 1 or 2):

History of a pleomorphic adenoma at the same site (~25% of cases^[1]).
Features of a pleomorphic adenoma and a carcinoma.

Epidemiology:

Rare.
Prognosis dependent on stage:
- Good for early lesions - like PA.^[2]
- Poor for advanced lesions.^[1]

Gross

Usually mass lesion - typically parotid gland.^[1]

Microscopic

Features:

Cells (epithelial or myoepithelial) with cytologic features of malignancy - key feature.
Architecture (any of the following):
- Glands.
- Nests.
- Single cells (may be subtle).

Subtyping/patterns:

Epithelial carcinoma (~75% of cases^[1]):
- Ductal carcinoma NOS (arising from ductal cells) - most common pattern for ca ex PA.
- "Named carcinoma":
  - Salivary duct carcinoma - second most common pattern for Ca ex PA.
  - Mucoepidermoid carcinoma.
  - Adenoid cystic carcinoma.
Myoepithelial carcinoma NOS (arising from myoepithelial cells).

Notes:

Myoepithelial cells may be clear cells.

DDx:

Subclassification

Extent of invasion:^[3]

Non-invasive AKA intracapsular AKA in situ.
Minimally invasive <=1.5 mm beyond the capsule.
Widely invasive >1.5 mm beyond the capsule.

Images

Ca ex PA - very low mag.
Ca ex PA - low mag.
Ca ex PA - low mag.
Ca ex PA - low mag.
Ca ex PA - intermed. mag.
Ca ex PA - intermed. mag.
Ca ex PA - high mag.
Ca ex PA - very high mag.

www:

IHC

Features - ca ex PA versus PA:^[2]

Ki-67 >35% of cells.
HER2 +ve membrane staining (3+ for high-grade, 2+ or less for low-grade).
p53 +ve.
AR +ve.

Others:^[2]

CK7 +ve.
AE1/AE3 +ve.

Sign out

PAROTID GLAND (MASS), LEFT, EXCISION:
- CARCINOMA EX PLEOMORPHIC ADENOMA, LOW-GRADE, INTRACAPSULAR.
-- MARGINS NEGATIVE.
-- SEE TUMOUR SUMMARY AND COMMENTS.
- THREE BENIGN LYMPH NODES.

Micro

The sections show a lesion with spindled (myoepithelial) cells and an epithelial component, on a background of a chondromyxoid stroma. The lesion is encapsulated by a thin layer of fibrous tissue.

Focally, within the lesion, nuclear atypia and mitotic activity are identified, including an atypical mitotic figure. The atypical region stains with p53. Approximately 45% of the atypical cells stain with Ki-67. There is no appreciable HER2 staining.

Unremarkable parotid gland and lymph nodes are present.

References

↑ ^1.0 ^1.1 ^1.2 ^1.3 ^1.4 ^1.5 Antony, J.; Gopalan, V.; Smith, RA.; Lam, AK. (Mar 2012). "Carcinoma ex pleomorphic adenoma: a comprehensive review of clinical, pathological and molecular data.". Head Neck Pathol 6 (1): 1-9. doi:10.1007/s12105-011-0281-z. PMID 21744105.
↑ ^2.0 ^2.1 ^2.2 Di Palma, S. (Jul 2013). "Carcinoma ex pleomorphic adenoma, with particular emphasis on early lesions.". Head Neck Pathol 7 Suppl 1: S68-76. doi:10.1007/s12105-013-0454-z. PMID 23821206.
↑ URL: http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/MajorSalGlands_11protocol.pdf. Accessed on: 2 April 2012.

[pmid21744105-1] 1.0 ^1.1 ^1.2 ^1.3 ^1.4 ^1.5 Antony, J.; Gopalan, V.; Smith, RA.; Lam, AK. (Mar 2012). "Carcinoma ex pleomorphic adenoma: a comprehensive review of clinical, pathological and molecular data.". Head Neck Pathol 6 (1): 1-9. doi:10.1007/s12105-011-0281-z. PMID 21744105.

[pmid23821206-2] 2.0 ^2.1 ^2.2 Di Palma, S. (Jul 2013). "Carcinoma ex pleomorphic adenoma, with particular emphasis on early lesions.". Head Neck Pathol 7 Suppl 1: S68-76. doi:10.1007/s12105-013-0454-z. PMID 23821206.

[3] URL: http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/MajorSalGlands_11protocol.pdf. Accessed on: 2 April 2012.

[1]

[2]

[3]

@@ Line 1: / Line 1: @@
 {{ Infobox diagnosis
 | Name       = {{PAGENAME}}
-| Image      =
+| Image      = Carcinoma ex pleomorphic adenoma -- low mag.jpg
 | Width      =
-| Caption    =
+| Caption    = Carcinoma ex pleomorphic adenoma. [[H&E stain]].
-| Micro      = cells with cytologic features of malignancy, pleomorphic adenoma (required if no hx)
+| Micro      = epithelial or myoepithelial cells with cytologic features of malignancy, pleomorphic adenoma (required if no history)
 | Subtypes   =
 | LMDDx      = [[salivary duct carcinoma]], [[mucoepidermoid carcinoma]], [[adenoid cystic carcinoma]], [[pleomorphic adenoma]]
@@ Line 45: / Line 45: @@
 ==Gross==
-*Usually mass lesion - typically partoid gland.<ref name=pmid21744105/>
+*Usually mass lesion - typically parotid gland.<ref name=pmid21744105/>
 ==Microscopic==
 Features:
-*Cells with cytologic features of malignancy - '''key feature'''.
+*Cells (epithelial or myoepithelial) with cytologic features of malignancy - '''key feature'''.
 *Architecture (any of the following):
 **Glands.
@@ Line 80: / Line 80: @@
 ===Images===
+<gallery>
+Image: Carcinoma ex pleomorphic adenoma -- very low mag.jpg | Ca ex PA - very low mag.
+Image: Carcinoma ex pleomorphic adenoma -- low mag.jpg | Ca ex PA - low mag.
+Image: Carcinoma ex pleomorphic adenoma - a1 -- low mag.jpg | Ca ex PA - low mag.
+Image: Carcinoma ex pleomorphic adenoma - a2 -- low mag.jpg | Ca ex PA - low mag.
+Image: Carcinoma ex pleomorphic adenoma -- intermed mag.jpg | Ca ex PA - intermed. mag.
+Image: Carcinoma ex pleomorphic adenoma - a1 -- intermed mag.jpg | Ca ex PA - intermed. mag.
+Image: Carcinoma ex pleomorphic adenoma -- high mag.jpg | Ca ex PA - high mag.
+Image: Carcinoma ex pleomorphic adenoma -- very high mag.jpg | Ca ex PA - very high mag.
+</gallery>
+www:
 *[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3311945/figure/Fig1/ Ca ex PA - showing ca and PA areas (nih.gov)].<ref name=pmid21744105/>
 *[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3311945/figure/Fig2/ Ca ex PA - showing capsule invasion (nih.gov)].
@@ Line 93: / Line 104: @@
 *CK7 +ve.
 *AE1/AE3 +ve.
+==Sign out==
+<pre>
+PAROTID GLAND (MASS), LEFT, EXCISION:
+- CARCINOMA EX PLEOMORPHIC ADENOMA, LOW-GRADE, INTRACAPSULAR.
+-- MARGINS NEGATIVE.
+-- SEE TUMOUR SUMMARY AND COMMENTS.
+- THREE BENIGN LYMPH NODES.
+</pre>
+===Micro===
+The sections show a lesion with spindled (myoepithelial) cells and an epithelial component,
+on a background of a chondromyxoid stroma. The lesion is encapsulated by a thin layer of
+fibrous tissue.
+Focally, within the lesion, nuclear atypia and mitotic activity are identified, including an atypical mitotic figure.  The atypical region stains with p53. Approximately 45% of the atypical cells stain with Ki-67.  There is no appreciable HER2 staining.
+Unremarkable parotid gland and lymph nodes are present.
 ==See also==