Pulmonary apical cap

2018-02-03T01:33:29Z

Arti: mature collagen

'''Pulmonary apical cap''', abbreviated '''PAC''', is a rare benign [[lung]] pathology that is found at one or both of the apices.<ref name=pmid26414471>{{Cite journal | last1 = Lagstein | first1 = A. | title = Pulmonary Apical Cap-What's Old Is New Again. | journal = Arch Pathol Lab Med | volume = 139 | issue = 10 | pages = 1258-62 | month = Oct | year = 2015 | doi = 10.5858/arpa.2015-0224-RA | PMID = 26414471 }}</ref>

==General==
*Possibly due to ischemia.<ref name=pmid11342783/>

==Gross==
*Spiculated mass at the apex - 0.7 to 5.2 cm.<ref name=pmid11342783>{{Cite journal | last1 = Yousem | first1 = SA. | title = Pulmonary apical cap: a distinctive but poorly recognized lesion in pulmonary surgical pathology. | journal = Am J Surg Pathol | volume = 25 | issue = 5 | pages = 679-83 | month = May | year = 2001 | doi = | PMID = 11342783 }}</ref>

==Microscopic==
Features:<ref name=pmid11342783/>
*Fibroelastotic scar with mature collagen and wavy/curled (accordion-like) elastic fibres.
*Alveolar enlargement at lesion periphery ("scar emphysema").

DDx:
*Scar associated with [[lung tumour]].

==See also==
*[[Lung tumours]].
*[[Cap polyposis]].

==References==
{{Reflist|1}}

[[Category:Diagnosis]]
[[Category:Lung tumours]]

Lung tumours

2018-02-03T01:23:20Z

Arti: nuclear staining with TTF-1 in a primary lung adenocarcinoma

[[Image:Small cell carcinoma (3931938372).jpg|right|thumb|300px|A lung tumour ([[small cell carcinoma of the lung]]) - centre of image. (WC/Rosen)]]
'''[[Lung]] tumours''' comes to pathology to get diagnosed.

This article deals with the surgical pathology (core biopsies, lung resections). Pulmonary cytopathology is dealt with in the ''[[pulmonary cytopathology]]'' article.

An introduction to lung pathology is found in the ''[[pulmonary pathology]]'' article.

=Lung tumours overview=
===Schematic overview of lung cancer (clinical)===
{{familytree/start}}
{{familytree | | | | | | | | | A01 | | | | |A01=Lung cancer}}
{{familytree | | | | |,|-|-|-|-|^|-|-|-|-|.|}}
{{familytree | | | | B01 | | | | | | | | B02|B01=Primary|B02=Metastatic }}
{{familytree | |,|-|-|^|-|-|.| | | | | | | | | | | | |}}
{{familytree | C01 | | | | C02 | | | | | | | | | | | |C01=NSCLC|C02=SCLC }}
{{familytree/end}}
*NSCLC = non-small cell lung cancer.
*SCLS = small cell lung cancer.

===Basic pathologic approach to lung cancer===

{{familytree/start}}
{{familytree | | | | | | | A | | | | | | |A=Lung cancer}}
{{familytree | |,|-|-|-|v|-|^|-|v|-|-|-|.| |}}
{{familytree | B | |C | |D | |E |B=Adenocarcinoma|C=Squamous<br>cell carcinoma|D=SCLC|E=LCLC}}
{{familytree/end}}
*LCLC = large cell lung cancer.
*SCLS = small cell lung cancer.

Notes:
*Most lung cancer fits into one of the above categories.
*All types may be metastatic. Pathologists usually don't have to sort this out, as the clinican often knows whether a given lesion is metastatic (when correlated with radiology).
*Lung cancers may have a mixed morphology, e.g. SCLS may have squamous component.<ref name=pmid17684766>{{cite journal |author=Righi L, Volante M, Rapa I, Scagliotti GV, Papotti M |title=Neuro-endocrine tumours of the lung. A review of relevant pathological and molecular data |journal=Virchows Arch. |volume=451 Suppl 1 |issue= |pages=S51–9 |year=2007 |month=August |pmid=17684766 |doi=10.1007/s00428-007-0445-0 |url=}}</ref>
*Categorization as ''non-small cell lung cancer'' (NSCLC) should be avoided, as treatment is now somewhat dependent on subcategorization.<ref>URL: [http://www.nature.com/modpathol/journal/v21/n2s/full/3801018a.html http://www.nature.com/modpathol/journal/v21/n2s/full/3801018a.html]. Accessed on: 8 September 2010.</ref>

===Major types (primary)===
Mnemonic ''ASSL'':
*[[Adenocarcinoma]].
*[[Squamous cell carcinoma]].
*[[Small cell carcinoma]] (SCLC).
*Large cell carcinoma (LCLC).

===Epidemiology===
*Adenocarcinoma is the most common (primary lung cancer).<ref>{{cite journal |author=Lutschg JH |title=Lung cancer |journal=N. Engl. J. Med. |volume=360 |issue=1 |pages=87-8; author reply 88 |year=2009 |month=January |pmid=19118313 |doi=10.1056/NEJMc082208 |url=}}</ref>
*Adenocarcinoma is the non-smoker tumour - SCLC and squamous are more strongly associated with [[smoking]].

===Distribution===
*Distribution - think about the location of letters in mnemonic ''ASSL''.
**Adenocarcinoma is usually periperal, i.e. smaller airways.
**Squamous cell carcinoma and small cell carcinoma are typically central.

===Margins in lung===
Margin in pneumonectomy specimens include:
*Vessels (artery, vein).
*Airway (bronchus).
*Soft tissue (lymphatics, fibrous tissue and lymph nodes).<ref name=pmid21129810>{{Cite journal | last1 = Sakai | first1 = Y. | last2 = Ohbayashi | first2 = C. | last3 = Kanomata | first3 = N. | last4 = Kajimoto | first4 = K. | last5 = Sakuma | first5 = T. | last6 = Maniwa | first6 = Y. | last7 = Nishio | first7 = W. | last8 = Tauchi | first8 = S. | last9 = Uchino | first9 = K. | title = Significance of microscopic invasion into hilar peribronchovascular soft tissue in resection specimens of primary non-small cell lung cancer. | journal = Lung Cancer | volume = 73 | issue = 1 | pages = 89-95 | month = Jul | year = 2011 | doi = 10.1016/j.lungcan.2010.11.002 | PMID = 21129810 }}</ref>

Notes:
*The traditional teaching is there are only hollow structure margins (artery, vein, airway) - yet the bronchial margin has been divided into mucosal and extramucosal.<ref>{{Cite journal | last1 = Kaiser | first1 = LR. | last2 = Fleshner | first2 = P. | last3 = Keller | first3 = S. | last4 = Martini | first4 = N. | title = Significance of extramucosal residual tumor at the bronchial resection margin. | journal = Ann Thorac Surg | volume = 47 | issue = 2 | pages = 265-9 | month = Feb | year = 1989 | doi = | PMID = 2537610 }}</ref>
*Peribronchovascular soft tissue involvement is a poor prognosticator but not an independent predictor if considered within the [[TNM staging]].<ref name=pmid21129810/>

===Management of primary lung cancer===
Management in the past was determined by categorization into:
*Small cell cancer.
*Non-small cell cancer (includes adenocarcinoma, squamous cell carcinoma, large cell carcinoma).

==Microscopic features overview==
===Adenocarcinoma===
{{Main|Adenocarcinoma of the lung}}
*Glands or cytoplasm with mucin.

===Squamous cell carcinoma===
{{Main|Squamous cell carcinoma of the lung}}
*Distinct cell borders with intercellular bridges.
*Eosinophilic cytoplasm.

===Small cell carcinoma===
{{Main|Small cell carcinoma of the lung}}
*Very cellular.
*Large [[NC ratio]] - very small amount of cytoplasm.
*Cells fragile - they tend to look "smudged" ([[Azzopardi phenomenon]]).

==IHC==
There is a great review paper by ''Jagirdar''.<ref name=pmid18318581>{{cite journal |author=Jagirdar J |title=Application of immunohistochemistry to the diagnosis of primary and metastatic carcinoma to the lung |journal=Arch. Pathol. Lab. Med. |volume=132 |issue=3 |pages=384-96 |year=2008 |month=March |pmid=18318581 |doi= |url=http://journals.allenpress.com/jrnlserv/?request=get-abstract&issn=0003-9985&volume=132&page=384}}</ref>

===Small cell carcinoma===
*[[TTF-1]] +ve.
*[[CD56]] +ve - sensitive.<ref name=pmid16862075>{{cite journal |author=Hiroshima K, Iyoda A, Shida T, ''et al'' |title=Distinction of pulmonary large cell neuroendocrine carcinoma from small cell lung carcinoma: a morphological, immunohistochemical, and molecular analysis |journal=Mod. Pathol. |volume=19 |issue=10 |pages=1358-68 |year=2006 |month=October |pmid=16862075 |doi=10.1038/modpathol.3800659 |url=}}</ref>
*[[CK7]] -ve, [[CK20]] -ve.

Note:
*CD56 - cytoplasmic.<ref>URL: [http://jcp.bmjjournals.com/content/58/9/978.full http://jcp.bmjjournals.com/content/58/9/978.full]. Accessed: 11 February 2010.</ref>

===Adenocarcinoma===
*[[TTF-1]] +ve.
*[[Napsin]] +ve - sensitive.<ref name=pmid22288963>{{cite journal |author=Turner BM, Cagle PT,Fukuoka J, ''et al'' |title=Napsin A, a New Marker for Lung Adenocarcinoma, Is Complementary and More Sensitive and Specific Than Thyroid Transcription Factor 1 in the Differential Diagnosis of Primary Pulmonary Carcinoma: Evaluation of 1674 Cases by Tissue Microarray |journal=Arch Pathol Lab Med. |volume=136 |issue=10 |pages=163-71 |year=2012 |month=February|pmid=22288963 |doi: 10.5858/arpa.2011-0320-OA|url=}}</ref>
*[[CK7]] +ve, [[CK20]] -ve.

===Squamous cell carcinoma===
*[[CK7]] -ve, CK20 -ve.
*HMWK +ve.
*Usually TTF-1 -ve.<ref>{{cite journal |author=Al-Zahrani IH |title=The value of immunohistochemical expression of TTF-1, CK7 and CK20 in the diagnosis of primary and secondary lung carcinomas |journal=Saudi Med J |volume=29 |issue=7 |pages=957-61 |year=2008 |month=July |pmid=18626520 |doi= |url=}}</ref>
*[[p40]] +ve.

===Primary vs. secondary===
*TTF-1 is considered useful.<ref name=pmid18318581/>
**75% +ve adenocarcinoma
**11% +ve SSC
**50% +ve large cell carcinoma
**0% +ve mesothelioma
**significant rates of +ve in some metastatic tumours -- see article by ''Jagirdar''.

Note:
*TTF-1 - should be nuclear staining; cytoplasmic staining is non-specific.<ref name=pmid15861215>{{cite journal |author=Compérat E, Zhang F, Perrotin C, ''et al.'' |title=Variable sensitivity and specificity of TTF-1 antibodies in lung metastatic adenocarcinoma of colorectal origin |journal=Mod. Pathol. |volume=18 |issue=10 |pages=1371–6 |year=2005 |month=October |pmid=15861215 |doi=10.1038/modpathol.3800422 |url=http://www.nature.com/modpathol/journal/v18/n10/full/3800422a.html}}</ref>
**Image: [http://commons.wikimedia.org/w/index.php?title=File:Lung_adenocarcinoma_-_TTF-1_-_high_mag.jpg Nuclear staining with TTF-1 in a primary lung adenocarcinoma (WC)].

==Neuroendocrine tumours==
{{Main|Neuroendocrine tumours}}
===Overview===
*This is a group of tumours that has benign (e.g. [[carcinoid]] tumour of the lung) to malignant (e.g. small cell lung carcinoma) behaviour.<ref>URL: [http://emedicine.medscape.com/article/426400-overview http://emedicine.medscape.com/article/426400-overview]. Accessed on: 20 January 2010.</ref>
*They are thought to arise from ''pulmonary neuroendocrine cells''.<ref>{{cite journal |author=Chong S, Lee KS, Chung MJ, Han J, Kwon OJ, Kim TS |title=Neuroendocrine tumors of the lung: clinical, pathologic, and imaging findings |journal=Radiographics |volume=26 |issue=1 |pages=41–57; discussion 57–8 |year=2006 |pmid=16418242 |doi=10.1148/rg.261055057 |url=}}</ref>

===Classification===
The grouping can be divided into four types:<ref name=cancerorg_car>URL: [http://www.cancer.org/docroot/CRI/content/CRI_2_4_1X_What_is_lung_carcinoid_tumor_56.asp http://www.cancer.org/docroot/CRI/content/CRI_2_4_1X_What_is_lung_carcinoid_tumor_56.asp]. Accessed on: 16 February 2011.</ref>
*Small cell carcinoma.
*Large cell neuroendocrine carcinoma.
*Typical carcinoid.
*Atypical carcinoid.

Notes:
*[[Typical carcinoid]]-like lesions <5 mm are called [[carcinoid tumourlet]]s.

===Cytologic features===
Cytologic features useful for differentiation:
*Small cell carcinoma: necrosis, scant cytoplasm, mitoses.
*Typical carcinoid: often more cytoplasm, no necrosis, low mitotic rate (MIB1: scant staining).
*Atypical carcinoid: higher mitotic rate/MIB1 than ''typical carcinoid'',<ref>Geddie, W. February 2010.</ref> no [[necrosis]].

Notes:<ref name=cancerorg_car/>
*''Large cell'' and ''small cell'' tumours behave in a similar fashion; ''large cell'' can be considered a morphological variant of ''small cell''.
*9/10 of carcinoids are ''typical'' and usually have a good prognosis, i.e. do not metastasize.
**Central location (vis-a-vis peripheral location) tends favours ''typical carcinoid'' over ''atypical carcinoid''.

=Malignant tumours=
==Adenocarcinoma of the lung==
*[[AKA]] ''lung adenocarcinoma''.
{{Main|Adenocarcinoma of the lung}}

==Bronchioloalveolar carcinoma==
:Abbreviated ''BAC''.

'''The term is no longer used''' in the new classification;<ref name=pmid21926387>{{Cite journal | last1 = Travis | first1 = WD. | last2 = Brambilla | first2 = E. | last3 = Noguchi | first3 = M. | last4 = Nicholson | first4 = AG. | last5 = Geisinger | first5 = K. | last6 = Yatabe | first6 = Y. | last7 = Powell | first7 = CA. | last8 = Beer | first8 = D. | last9 = Riely | first9 = G. | title = International association for the study of lung cancer/American Thoracic Society/European Respiratory Society: international multidisciplinary classification of lung adenocarcinoma: executive summary. | journal = Proc Am Thorac Soc | volume = 8 | issue = 5 | pages = 381-5 | month = Sep | year = 2011 | doi = 10.1513/pats.201107-042ST | PMID = 21926387 |URL = http://iaslc.org/assets/Documents/lung-adenocarcinoma-classification.pdf }}</ref> it is now "adenocarcinoma in situ" - see ''[[lung adenocarcinoma]]''.

==Squamous cell carcinoma of the lung==
{{Main|Squamous cell carcinoma of the lung}}

==Small cell carcinoma of the lung==
*[[AKA]] ''small cell lung carcinoma'', abbreviated ''SCLC''.<ref name=pmid20943645>{{Cite journal | last1 = Travis | first1 = WD. | title = Advances in neuroendocrine lung tumors. | journal = Ann Oncol | volume = 21 Suppl 7 | issue = | pages = vii65-71 | month = Oct | year = 2010 | doi = 10.1093/annonc/mdq380 | PMID = 20943645 }}</ref>
{{Main|Small cell carcinoma of the lung}}

==Malignant mesothelioma==
:Should '''not''' be confused with ''[[benign multicystic mesothelioma]]'' and ''[[benign papillary mesothelioma]]''.
{{Main|Malignant mesothelioma}}

==Non-small cell lung carcinoma==
*[[AKA]] ''poorly differentiated carcinoma of the lung''.
{{Main|Non-small cell lung carcinoma}}

==Adenosquamous carcinoma of the lung==
{{Main|Adenosquamous carcinoma of the lung}}

==Lung metastasis==
*[[AKA]] ''pulmonary metastasis''.
{{Main|Lung metastasis}}

=Malignant potential=
==Atypical alveolar hyperplasia==
*Abbreviated ''AAH''.
*[[AKA]] ''atypical adenomatous hyperplasia of the lung''.<ref name=pmid11235908>{{Cite journal | last1 = Mori | first1 = M. | last2 = Rao | first2 = SK. | last3 = Popper | first3 = HH. | last4 = Cagle | first4 = PT. | last5 = Fraire | first5 = AE. | title = Atypical adenomatous hyperplasia of the lung: a probable forerunner in the development of adenocarcinoma of the lung. | journal = Mod Pathol | volume = 14 | issue = 2 | pages = 72-84 | month = Feb | year = 2001 | doi = 10.1038/modpathol.3880259 | PMID = 11235908 }}</ref>
{{Main|Atypical adenomatous hyperplasia of the lung}}

==Atypical carcinoid lung tumour==
*[[AKA]] ''atypical carcinoid tumour of the lung''.
{{Main|Atypical lung carcinoid tumour}}

==Solitary fibrous tumour of the pleura==
{{Main|Solitary fibrous tumour of the pleura}}

=Benign tumours=
==Pulmonary apical cap==
{{Main|Pulmonary apical cap}}
A lesion that can mimic a lung neoplasm.

==Pulmonary carcinoid tumourlet==
*[[AKA]] ''carcinoid tumourlet''.
{{Main|Pulmonary carcinoid tumourlet}}

==Typical carcinoid lung tumour==
*[[AKA]] ''carcinoid tumour of the lung''.
*[[AKA]] ''lung carcinoid''.
{{Main|Typical carcinoid lung tumour}}

==Clear cell sugar tumour of the lung==
*[[AKA]] ''clear cell sugar tumour''.
**Abbreviated ''CCST''.
{{Main|Clear cell sugar tumour of the lung}}

=See also=
*[[Lung]] - introduction to the lung, includes a basic approach.
*[[Medical lung disease]].
*[[Thyroid]].
*[[Basics]].
*[[Heart]].
*[[Missed endobronchial biopsy]].

=References=
{{reflist|2}}

[[Category:Pulmonary pathology]]

Libre Pathology - User contributions [en]

Pulmonary apical cap

Lung tumours