Urethral cancer pathophysiology: Difference between revisions

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==Overview==
==Overview==
Urethral cancer is a rare disease. The [[pathophysiology]] of [[Urethral cancer|urethral]] [[cancer]] depends on the [[histological]] subtypes. It could be primary from epithelial origin or secondary like from [[bladder cancer]] which is more common than primary type.
Urethral cancer is a rare disease. The [[pathophysiology]] of [[Urethral cancer|urethral]] [[cancer]] depends on the [[histological]] subtypes. It could be primary from epithelial origin or secondary like from [[bladder cancer]] which is more common than primary type <ref name="pmid27720774">{{cite journal |vauthors=Sui W, RoyChoudhury A, Wenske S, Decastro GJ, McKiernan JM, Anderson CB |title=Outcomes and Prognostic Factors of Primary Urethral Cancer |journal=Urology |volume=100 |issue= |pages=180–186 |date=February 2017 |pmid=27720774 |doi=10.1016/j.urology.2016.09.042 |url=}}</ref> <ref name="pmid27717437">{{cite journal |vauthors=Zargar-Shoshtari K, Sexton WJ, Poch MA |title=Management of Urethral Recurrences: Urothelial and Nonurothelial |journal=Urol. Clin. North Am. |volume=43 |issue=4 |pages=515–521 |date=November 2016 |pmid=27717437 |doi=10.1016/j.ucl.2016.06.012 |url=}}</ref>.


== Pathogenesis ==
== Pathogenesis ==


[[Mucous|Mucous cell]]<nowiki/>s in the [[urethra]] have the ability to turnover rapidly. In primary type of the urethral cancer It has been suggested that defect in [[DNA repair]] mechanism may cause urethral cancer. Other etiologies for primary types are:
[[Mucous|Mucous cell]]<nowiki/>s in the [[urethra]] have the ability to turnover rapidly. In primary type of the urethral cancer It has been suggested that defect in "'''[[DNA repair]] mechanism'''" may cause urethral cancer.
 
Chronic inflammation and strictures: May happen after any surgery on urethra like [[urethroplasty]] <ref name="pmid916053">{{cite journal |vauthors=Colapinto V, Evans DH |title=Primary carcinoma of the male urethra developing after urethroplasty for stricture |journal=J. Urol. |volume=118 |issue=4 |pages=581–4 |date=October 1977 |pmid=916053 |doi= |url=}}</ref>.
* Infection: [[Sexually transmitted disease|sexually transmitted diseases]] like [[HPV]] type 16 <ref name="pmid8886059">{{cite journal |vauthors=Cupp MR, Malek RS, Goellner JR, Espy MJ, Smith TF |title=Detection of human papillomavirus DNA in primary squamous cell carcinoma of the male urethra |journal=Urology |volume=48 |issue=4 |pages=551–5 |date=October 1996 |pmid=8886059 |doi=10.1016/S0090-4295(96)00246-4 |url=}}</ref>.  


Other etiologies for primary types are <ref name="pmid25347253">{{cite journal |vauthors=Klemann N, Toft BG, Thind P |title=[Urethral cancer is rare and difficult to diagnose] |language=Danish |journal=Ugeskr. Laeg. |volume=176 |issue=4A |pages=V07130435 |date=January 2014 |pmid=25347253 |doi= |url=}}</ref>:
* Chronic inflammation and strictures: May happen after any surgery on urethra like [[urethroplasty]] <ref name="pmid916053">{{cite journal |vauthors=Colapinto V, Evans DH |title=Primary carcinoma of the male urethra developing after urethroplasty for stricture |journal=J. Urol. |volume=118 |issue=4 |pages=581–4 |date=October 1977 |pmid=916053 |doi= |url=}}</ref><ref name="pmid28776126">{{cite journal |vauthors=Browne BM, Vanni AJ |title=Management of Urethral Stricture and Bladder Neck Contracture Following Primary and Salvage Treatment of Prostate Cancer |journal=Curr Urol Rep |volume=18 |issue=10 |pages=76 |date=October 2017 |pmid=28776126 |doi=10.1007/s11934-017-0729-0 |url=}}</ref>.
* Infection: [[Sexually transmitted disease|sexually transmitted diseases]] like [[HPV]] type 16 <ref name="pmid8886059">{{cite journal |vauthors=Cupp MR, Malek RS, Goellner JR, Espy MJ, Smith TF |title=Detection of human papillomavirus DNA in primary squamous cell carcinoma of the male urethra |journal=Urology |volume=48 |issue=4 |pages=551–5 |date=October 1996 |pmid=8886059 |doi=10.1016/S0090-4295(96)00246-4 |url=}}</ref>.
* External [[radiation therapy]] <ref name="pmid12588611">{{cite journal |vauthors=Mohan H, Bal A, Punia RP, Bawa AS |title=Squamous cell carcinoma of the prostate |journal=Int. J. Urol. |volume=10 |issue=2 |pages=114–6 |date=February 2003 |pmid=12588611 |doi= |url=}}</ref>
* External [[radiation therapy]] <ref name="pmid12588611">{{cite journal |vauthors=Mohan H, Bal A, Punia RP, Bawa AS |title=Squamous cell carcinoma of the prostate |journal=Int. J. Urol. |volume=10 |issue=2 |pages=114–6 |date=February 2003 |pmid=12588611 |doi= |url=}}</ref>


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* Other: [[Arsenic]] ingestion
* Other: [[Arsenic]] ingestion
Also the pathogenesis is different in male and female.


In male [[Prostate|prostatic]] and membranous portions of the urethra cancer are more from [[bladder cancer]]. Bulbous and membranous portions urethral cancers are most commonly [[squamous cell carcinoma]].
* Although cigarette smoking can cause bladder cancer but the role of it in causing primary urethral cancer is still unknown.


In female proximal 2/3 of the urethral cancer are more primary types and distal 1/3 is usually squamous cell carcinoma.
==== The pathogenesis is different in male and female: ====
* '''Male''': [[Prostate|Prostatic]] and membranous portions of the urethra cancer are more from [[bladder cancer]]. Bulbous and membranous portions urethral cancers are most commonly [[squamous cell carcinoma]].
 
* '''Female''': Proximal 2/3 of the urethral cancer are more primary types and distal 1/3 is usually squamous cell carcinoma.


== Genetics ==
== Genetics ==
The exact gene and mutations that cause urethral cancer are unlnown.   
The exact gene and mutations that cause urethral cancer are unknown. But below genetic correlation are known to be involved in the pathogenesis:  
* [[Mutation]] in TERT promoter, [[PAX8]], [[GATA3]], P63, P40, [[p53]] may play role in sarcomatoid urothelial carcinoma <ref name="pmid28052688">{{cite journal |vauthors=Wang X, Lopez-Beltran A, Osunkoya AO, Wang M, Zhang S, Davidson DD, Emerson RE, Williamson SR, Tan PH, Kaimakliotis HZ, Baldridge LA, MacLennan GT, Montironi R, Cheng L |title=TERT promoter mutation status in sarcomatoid urothelial carcinomas of the upper urinary tract |journal=Future Oncol |volume=13 |issue=8 |pages=705–714 |date=April 2017 |pmid=28052688 |doi=10.2217/fon-2016-0414 |url=}}</ref>. 
* [[Fragile histidine triad]] ([[FHIT]]) gene may play a role in causing [[Bladder|bladde]]<nowiki/>r urothelial carcinoma <ref name="pmid22613411">{{cite journal |vauthors=Zhang CT, Lu R, Lin YL, Liu RL, Zhang ZH, Yang K, Dang RF, Zhang HT, Shen YG, Kong PZ, Ren HL, Li XL, Quan W, Xu Y |title=The significance of fragile histidine triad protein as a molecular prognostic marker of bladder urothelial carcinoma |journal=J. Int. Med. Res. |volume=40 |issue=2 |pages=507–16 |date=2012 |pmid=22613411 |doi=10.1177/147323001204000212 |url=}}</ref>. 


[[Mutation]] in TERT promoter, [[PAX8]], [[GATA3]], P63, P40, [[p53]] may play role in sarcomatoid urothelial carcinoma <ref name="pmid28052688">{{cite journal |vauthors=Wang X, Lopez-Beltran A, Osunkoya AO, Wang M, Zhang S, Davidson DD, Emerson RE, Williamson SR, Tan PH, Kaimakliotis HZ, Baldridge LA, MacLennan GT, Montironi R, Cheng L |title=TERT promoter mutation status in sarcomatoid urothelial carcinomas of the upper urinary tract |journal=Future Oncol |volume=13 |issue=8 |pages=705–714 |date=April 2017 |pmid=28052688 |doi=10.2217/fon-2016-0414 |url=}}</ref>.
* Overexpression of the semaphorin 3A in patients with [[urethral]] cancer has been reported <ref name="pmid29288007">{{cite journal |vauthors=Vadasz Z, Rubinstein J, Bejar J, Sheffer H, Halachmi S |title=Overexpression of semaphorin 3A in patients with urothelial cancer |journal=Urol. Oncol. |volume=36 |issue=4 |pages=161.e1–161.e6 |date=April 2018 |pmid=29288007 |doi=10.1016/j.urolonc.2017.12.007 |url=}}</ref>.


[[Fragile histidine triad]] ([[FHIT]]) gene may play a role in causing [[Bladder|bladde]]<nowiki/>r urothelial carcinoma <ref name="pmid22613411">{{cite journal |vauthors=Zhang CT, Lu R, Lin YL, Liu RL, Zhang ZH, Yang K, Dang RF, Zhang HT, Shen YG, Kong PZ, Ren HL, Li XL, Quan W, Xu Y |title=The significance of fragile histidine triad protein as a molecular prognostic marker of bladder urothelial carcinoma |journal=J. Int. Med. Res. |volume=40 |issue=2 |pages=507–16 |date=2012 |pmid=22613411 |doi=10.1177/147323001204000212 |url=}}</ref>. 
== Associated Conditions ==
* Urethral cancers in proximal urethra have worse prognosis than those arising in the distal portion in men.


== Gross Pathology ==
== Gross Pathology ==
In end stage type they may appear as an exophytic mass.
In end stage type, they may appear as an exophytic mass.


==Microscopic Pathology==
==Microscopic Pathology==
The microscopic view of [[urethral cancer]] is depended on the location of teh cancer. The type of the cancer in the distal part of the urethra is usually [[squamous cell]]. <ref name="pmid23116581">{{cite journal |vauthors=Grivas PD, Davenport M, Montie JE, Kunju LP, Feng F, Weizer AZ |title=Urethral cancer |journal=Hematol. Oncol. Clin. North Am. |volume=26 |issue=6 |pages=1291–314 |date=December 2012 |pmid=23116581 |doi=10.1016/j.hoc.2012.08.006 |url=}}</ref>
The microscopic view of [[urethral cancer]] is depended on the location of the cancer. The type of the cancer in the distal part of the urethra is usually [[squamous cell]]. <ref name="pmid23116581">{{cite journal |vauthors=Grivas PD, Davenport M, Montie JE, Kunju LP, Feng F, Weizer AZ |title=Urethral cancer |journal=Hematol. Oncol. Clin. North Am. |volume=26 |issue=6 |pages=1291–314 |date=December 2012 |pmid=23116581 |doi=10.1016/j.hoc.2012.08.006 |url=}}</ref>
* [[Female]]<ref name="pmid23608423">{{cite journal |vauthors=Cantiello F, Cicione A, Salonia A, Autorino R, Tucci L, Madeo I, Damiano R |title=Periurethral fibrosis secondary to prostatic inflammation causing lower urinary tract symptoms: a prospective cohort study |journal=Urology |volume=81 |issue=5 |pages=1018–23 |date=May 2013 |pmid=23608423 |doi=10.1016/j.urology.2013.01.053 |url=}}</ref>
* [[Female]]<ref name="pmid23608423">{{cite journal |vauthors=Cantiello F, Cicione A, Salonia A, Autorino R, Tucci L, Madeo I, Damiano R |title=Periurethral fibrosis secondary to prostatic inflammation causing lower urinary tract symptoms: a prospective cohort study |journal=Urology |volume=81 |issue=5 |pages=1018–23 |date=May 2013 |pmid=23608423 |doi=10.1016/j.urology.2013.01.053 |url=}}</ref>
:* The [[female]] [[urethra]] is lined by [[transitional cell]] [[mucosa]] proximally and [[stratified]] [[squamous]] cells distally.  
** The [[female]] [[urethra]] is lined by [[transitional cell]] [[mucosa]] proximally and [[stratified]] [[squamous]] cells distally.
:* Therefore, [[transitional cell carcinoma]] is most common in the [[proximal]] [[urethra]]  
** Therefore, [[transitional cell carcinoma]] is most common in the [[proximal]] [[urethra]]
:* [[Adenocarcinoma]] may occur in both locations and arises from [[metaplasia]] of the numerous [[Periurethral phlegmon|periurethral]] [[glands]].
** [[Adenocarcinoma]] may occur in both locations and arises from [[metaplasia]] of the numerous [[Periurethral phlegmon|periurethral]] [[glands]].


* [[Male]]
* [[Male]]
:* The [[male]] [[urethra]] is lined by [[transitional]] cells in its [[prostatic]] and [[Membranous glomerulonephritis|membranous]] portion and [[stratified]] [[Columnar epithelia|columnar]] [[epithelium]] to [[stratified squamous epithelium]] in the [[Bulbous nose|bulbous]] and [[Penile discharge|penile]] portions.  
** The [[male]] [[urethra]] is lined by [[transitional]] cells in its [[prostatic]] and [[Membranous glomerulonephritis|membranous]] portion and [[stratified]] [[Columnar epithelia|columnar]] [[epithelium]] to [[stratified squamous epithelium]] in the [[Bulbous nose|bulbous]] and [[Penile discharge|penile]] portions.
:* The [[submucosa]] of the [[urethra]] contains numerous glands.
** The [[submucosa]] of the [[urethra]] contains numerous glands.
:* Therefore, [[Urethral cancer|urethral]] cancer in the [[male]] can manifest the histological characteristics of [[transitional cell carcinoma]], [[squamous cell carcinoma]], or [[adenocarcinoma]].
** Therefore, [[Urethral cancer|urethral]] cancer in the [[male]] can manifest the histological characteristics of [[transitional cell carcinoma]], [[squamous cell carcinoma]], or [[adenocarcinoma]].
:* Except for the [[prostatic urethra]], where [[transitional cell carcinoma]] is most common, [[squamous cell carcinoma]] is the predominant [[histology]] of [[urethral]] [[neoplasms]].
** Adenocarcinoma in the [[urethra]] is commonly associated with [[Diverticular disease|diverticula]] and [[prostatic]] adenocarcinoma.
:* [[Transitional cell carcinoma]] of the [[prostatic urethra]] may be associated with [[transitional cell carcinoma]] of the [[bladder]] and/or [[transitional cell]] [[carcinoma]] arising in [[prostatic ducts]]. Histology based on the types of the cancer:
** Except for the [[prostatic urethra]], where [[transitional cell carcinoma]] is most common, [[squamous cell carcinoma]] is the predominant [[histology]] of [[urethral]] [[neoplasms]].
::**[[SCC]]:  high [[mitotic]] activity, nuclear atypia. Positive with cytoplasmic beta-catenin stain. pleomorphic tumor cells with focal or abundant [[keratinization]], intercellular bridges. Stains: High molecular weight cytokeratin (CK903, CK5/6), p63, p16.
** [[Transitional cell carcinoma]] of the [[prostatic urethra]] may be associated with [[transitional cell carcinoma]] of the [[bladder]] and/or [[transitional cell]] [[carcinoma]] arising in [[prostatic ducts]].  
::**[[Adenocarcinoma]]:  simple or [[Pseudostratified columnar|pseudostratified]] columnar epithelium with [[hyperchromatic]] nuclei. vacuolated cytoplasm with mucin pools. Stains: P53, CK20.
 
::**[[Clear Cell]]: clear or [[eosinophilic]] cytoplasm, vacuoles in the cytoplasm, hyperchromatic nuclei. Positive with  [[p53]] and vimentin stain. Hobnail changes and extracellular mucoid material.
=== Histology based on the types of the cancer: ===
* [[SCC|'''SCC''']]:  high [[mitotic]] activity, nuclear atypia. Positive with cytoplasmic beta-catenin stain. pleomorphic tumor cells with focal or abundant [[keratinization]], intercellular bridges. Stains: High molecular weight cytokeratin (CK903, CK5/6), p63, p16.
 
* [[Adenocarcinoma|'''Adenocarcinoma''']] <ref name="pmid29516944">{{cite journal |vauthors=Mallya V, Mallya A, Gayathri J |title=Clear cell adenocarcinoma of the urethra with inguinal lymph node metastases: A rare case report and review of literature |journal=J Cancer Res Ther |volume=14 |issue=2 |pages=468–470 |date=2018 |pmid=29516944 |doi=10.4103/0973-1482.226734 |url=}}</ref>:  simple or [[Pseudostratified columnar|pseudostratified]] columnar epithelium with [[hyperchromatic]] nuclei. vacuolated cytoplasm with mucin pools. Stains: P53, CK20.
 
* [[Clear Cell|'''Clear Cell''']]: clear or [[eosinophilic]] cytoplasm, vacuoles in the cytoplasm, hyperchromatic nuclei. Positive with  [[p53]] and vimentin stain. Hobnail changes and extracellular mucoid material.


==References==
==References==

Latest revision as of 15:44, 22 January 2019

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Vindhya BellamKonda, M.B.B.S [2], Aida Javanbakht, M.D.

Overview

Urethral cancer is a rare disease. The pathophysiology of urethral cancer depends on the histological subtypes. It could be primary from epithelial origin or secondary like from bladder cancer which is more common than primary type [1] [2].

Pathogenesis

Mucous cells in the urethra have the ability to turnover rapidly. In primary type of the urethral cancer It has been suggested that defect in "DNA repair mechanism" may cause urethral cancer.

Other etiologies for primary types are [3]:

  • Although cigarette smoking can cause bladder cancer but the role of it in causing primary urethral cancer is still unknown.

The pathogenesis is different in male and female:

  • Female: Proximal 2/3 of the urethral cancer are more primary types and distal 1/3 is usually squamous cell carcinoma.

Genetics

The exact gene and mutations that cause urethral cancer are unknown. But below genetic correlation are known to be involved in the pathogenesis:

  • Overexpression of the semaphorin 3A in patients with urethral cancer has been reported [11].

Associated Conditions

  • Urethral cancers in proximal urethra have worse prognosis than those arising in the distal portion in men.

Gross Pathology

In end stage type, they may appear as an exophytic mass.

Microscopic Pathology

The microscopic view of urethral cancer is depended on the location of the cancer. The type of the cancer in the distal part of the urethra is usually squamous cell. [12]

Histology based on the types of the cancer:

  • SCC: high mitotic activity, nuclear atypia. Positive with cytoplasmic beta-catenin stain. pleomorphic tumor cells with focal or abundant keratinization, intercellular bridges. Stains: High molecular weight cytokeratin (CK903, CK5/6), p63, p16.
  • Clear Cell: clear or eosinophilic cytoplasm, vacuoles in the cytoplasm, hyperchromatic nuclei. Positive with  p53 and vimentin stain. Hobnail changes and extracellular mucoid material.

References

  1. Sui W, RoyChoudhury A, Wenske S, Decastro GJ, McKiernan JM, Anderson CB (February 2017). "Outcomes and Prognostic Factors of Primary Urethral Cancer". Urology. 100: 180–186. doi:10.1016/j.urology.2016.09.042. PMID 27720774.
  2. Zargar-Shoshtari K, Sexton WJ, Poch MA (November 2016). "Management of Urethral Recurrences: Urothelial and Nonurothelial". Urol. Clin. North Am. 43 (4): 515–521. doi:10.1016/j.ucl.2016.06.012. PMID 27717437.
  3. Klemann N, Toft BG, Thind P (January 2014). "[Urethral cancer is rare and difficult to diagnose]". Ugeskr. Laeg. (in Danish). 176 (4A): V07130435. PMID 25347253.
  4. Colapinto V, Evans DH (October 1977). "Primary carcinoma of the male urethra developing after urethroplasty for stricture". J. Urol. 118 (4): 581–4. PMID 916053.
  5. Browne BM, Vanni AJ (October 2017). "Management of Urethral Stricture and Bladder Neck Contracture Following Primary and Salvage Treatment of Prostate Cancer". Curr Urol Rep. 18 (10): 76. doi:10.1007/s11934-017-0729-0. PMID 28776126.
  6. Cupp MR, Malek RS, Goellner JR, Espy MJ, Smith TF (October 1996). "Detection of human papillomavirus DNA in primary squamous cell carcinoma of the male urethra". Urology. 48 (4): 551–5. doi:10.1016/S0090-4295(96)00246-4. PMID 8886059.
  7. Mohan H, Bal A, Punia RP, Bawa AS (February 2003). "Squamous cell carcinoma of the prostate". Int. J. Urol. 10 (2): 114–6. PMID 12588611.
  8. Ahmed K, Dasgupta R, Vats A, Nagpal K, Ashrafian H, Kaj B, Athanasiou T, Dasgupta P, Khan MS (June 2010). "Urethral diverticular carcinoma: an overview of current trends in diagnosis and management". Int Urol Nephrol. 42 (2): 331–41. doi:10.1007/s11255-009-9618-x. PMID 19649767.
  9. Wang X, Lopez-Beltran A, Osunkoya AO, Wang M, Zhang S, Davidson DD, Emerson RE, Williamson SR, Tan PH, Kaimakliotis HZ, Baldridge LA, MacLennan GT, Montironi R, Cheng L (April 2017). "TERT promoter mutation status in sarcomatoid urothelial carcinomas of the upper urinary tract". Future Oncol. 13 (8): 705–714. doi:10.2217/fon-2016-0414. PMID 28052688.
  10. Zhang CT, Lu R, Lin YL, Liu RL, Zhang ZH, Yang K, Dang RF, Zhang HT, Shen YG, Kong PZ, Ren HL, Li XL, Quan W, Xu Y (2012). "The significance of fragile histidine triad protein as a molecular prognostic marker of bladder urothelial carcinoma". J. Int. Med. Res. 40 (2): 507–16. doi:10.1177/147323001204000212. PMID 22613411.
  11. Vadasz Z, Rubinstein J, Bejar J, Sheffer H, Halachmi S (April 2018). "Overexpression of semaphorin 3A in patients with urothelial cancer". Urol. Oncol. 36 (4): 161.e1–161.e6. doi:10.1016/j.urolonc.2017.12.007. PMID 29288007.
  12. Grivas PD, Davenport M, Montie JE, Kunju LP, Feng F, Weizer AZ (December 2012). "Urethral cancer". Hematol. Oncol. Clin. North Am. 26 (6): 1291–314. doi:10.1016/j.hoc.2012.08.006. PMID 23116581.
  13. Cantiello F, Cicione A, Salonia A, Autorino R, Tucci L, Madeo I, Damiano R (May 2013). "Periurethral fibrosis secondary to prostatic inflammation causing lower urinary tract symptoms: a prospective cohort study". Urology. 81 (5): 1018–23. doi:10.1016/j.urology.2013.01.053. PMID 23608423.
  14. Mallya V, Mallya A, Gayathri J (2018). "Clear cell adenocarcinoma of the urethra with inguinal lymph node metastases: A rare case report and review of literature". J Cancer Res Ther. 14 (2): 468–470. doi:10.4103/0973-1482.226734. PMID 29516944.