Pseudomyxoma peritonei overview: Difference between revisions

Jump to navigation Jump to search
No edit summary
 
(4 intermediate revisions by the same user not shown)
Line 4: Line 4:


==Overview==
==Overview==
Pseudomyxoma peritonei is a very rare [[tumor]] characterized by the presence of abundant [[mucus]] in the abdominal cavity, consisting of intraperitoneal mucinous tumors and [[ascites]], most commonly arising from mucinous [[Tumor|tumors]] of the [[appendix]], however, the [[ovary]] or the [[colon]] may be the primary site of origin. The [[tumor]] is not harmful by itself, but the [[mucus]] accumulation in [[abdominal]] cavity compresses vital organs such as [[spleen]], [[kidney]], [[colon]]. On 1842, Carl F. Rokitansky described the first case of pseudomyxoma peritonei.  Pseudomyxoma peritonei may be divided into two [[pathological]] subtypes with different [[etiology]] and [[prognosis]], these two subtypes are peritoneal adenomucinosis and [[Mucinous carcinoma|peritoneal mucinous carcinoma]]. The ''[[Ras|K-Ras]]'' and [[P53 gene|''p53'' genes]] are involved in the [[oncogenesis]]. Pseudomyxoma peritonei must be differentiated from peritoneal carcinomatosis without mucinous [[ascites]], [[peritoneal]] sarcomatosis, and [[tuberculosis]] peritonitis. The [[Incidence rate|incidence]] of pseudomyxoma peritonei is approximately 0.1 person per 100,000 individuals worldwide. Females are more commonly affected with pseudomyxoma peritonei than males. The median age at diagnosis is 50 years. There are no established risk factors for pseudomyxoma peritonei. Patients with pseudomyxoma peritonei may develop [[abdominal]] or [[pelvic]] pain, [[bloating]], [[abdominal distension]], weight change, and [[infertility]] symptoms if left untreated. Common [[physical examination]] findings of pseudomyxoma peritonei include [[abdominal tenderness]], [[Abdominal distension|abdominal distention]]. On abdominal [[CT scan]], pseudomyxoma peritonei is characterized by low attenuation, loculated [[ascitic]] mucinous fluid in the [[peritoneum]], [[omentum]] and [[mesentery]] with scalloping of visceral surfaces of the [[liver]]. On abdominal MRI, pseudomyxoma peritonei is characterized by a mass which is hypointense on T1-weighted [[MRI]] and hyperintense on T2-weighted [[MRI]]. Finding on ultrasound scan suggestive of pseudomyxoma peritonei are echogenic peritoneal masses or [[ascites]] which is not mobile. Cytoreductive [[Surgery operation|surgery]] combined with [[hyperthermic intraperitoneal chemoperfusion]] is the optimal way of treatment for pseudomyxoma peritonei.
Pseudomyxoma peritonei is a very rare [[tumor]] characterized by the presence of abundant [[mucus]] in the [[abdominal cavity]], consisting of [[intraperitoneal]] [[mucinous]] [[Tumor|tumors]] and [[ascites]], most commonly arising from [[mucinous]] [[Tumor|tumors]] of the [[appendix]], however, the [[ovary]] or the [[colon]] may be the primary site of origin. The [[tumor]] is not harmful by itself, but the [[mucus]] accumulation in [[abdominal]] cavity compresses vital organs such as [[spleen]], [[kidney]], [[colon]]. On 1842, Carl F. Rokitansky described the first case of pseudomyxoma peritonei.  Pseudomyxoma peritonei may be divided into two [[pathological]] subtypes with different [[etiology]] and [[prognosis]], these two subtypes are peritoneal adenomucinosis and [[Mucinous carcinoma|peritoneal mucinous carcinoma]]. The ''[[Ras|K-Ras]]'' and [[P53 gene|''p53'' genes]] are involved in the [[oncogenesis]]. Pseudomyxoma peritonei must be differentiated from peritoneal carcinomatosis without mucinous [[ascites]], [[peritoneal]] sarcomatosis, and [[tuberculosis]] peritonitis. The [[Incidence rate|incidence]] of pseudomyxoma peritonei is approximately 0.1 person per 100,000 individuals worldwide. Females are more commonly affected with pseudomyxoma peritonei than males. The median age at diagnosis is 50 years. There are no established risk factors for pseudomyxoma peritonei. Patients with pseudomyxoma peritonei may develop [[abdominal]] or [[pelvic]] pain, [[bloating]], [[abdominal distension]], weight change, and [[infertility]] symptoms if left untreated. Common [[physical examination]] findings of pseudomyxoma peritonei include [[abdominal tenderness]], [[Abdominal distension|abdominal distention]]. On abdominal [[CT scan]], pseudomyxoma peritonei is characterized by low attenuation, loculated [[ascitic]] mucinous fluid in the [[peritoneum]], [[omentum]] and [[mesentery]] with scalloping of visceral surfaces of the [[liver]]. On abdominal MRI, pseudomyxoma peritonei is characterized by a [[mass]] which is hypointense on T1-weighted [[MRI]] and hyperintense on T2-weighted [[MRI]]. Finding on [[ultrasound scan]] suggestive of pseudomyxoma peritonei are echogenic [[Peritoneal|peritoneal masses]] or [[ascites]] which is not mobile. Cytoreductive [[Surgery operation|surgery]] combined with [[hyperthermic intraperitoneal chemoperfusion]] is the optimal way of treatment for pseudomyxoma peritonei.


==Historical Perspective==
==Historical Perspective==
The first case of pseudomyxoma peritonei was described by Carl F. Rokitansky in 1842.<ref name="pmid12163380">{{cite journal |vauthors=O'Connell JT, Tomlinson JS, Roberts AA, McGonigle KF, Barsky SH |title=Pseudomyxoma peritonei is a disease of MUC2-expressing goblet cells |journal=Am. J. Pathol. |volume=161 |issue=2 |pages=551–64 |date=August 2002 |pmid=12163380 |pmc=1850719 |doi=10.1016/S0002-9440(10)64211-3 |url=}}</ref>
The first case of pseudomyxoma peritonei was described by Carl F. Rokitansky in 1842.


==Pathophysiology==
==Pathophysiology==
Pseudomyxoma peritonei is a rare poorly understood [[neoplasm]] which may be divided into two pathological subtypes: [[Disseminated peritoneal adenomucinosis]] (DPAM), and [[Peritoneal mucinous carcinomatosis]] (PMCA).<ref name="pmid26475379">{{cite journal |vauthors=Noguchi R, Yano H, Gohda Y, Suda R, Igari T, Ohta Y, Yamashita N, Yamaguchi K, Terakado Y, Ikenoue T, Furukawa Y |title=Molecular profiles of high-grade and low-grade pseudomyxoma peritonei |journal=Cancer Med |volume=4 |issue=12 |pages=1809–16 |date=December 2015 |pmid=26475379 |pmc=5123786 |doi=10.1002/cam4.542 |url=}}</ref>
Pseudomyxoma peritonei is a rare poorly understood [[neoplasm]] which may be divided into two pathological subtypes: [[Disseminated peritoneal adenomucinosis]] (DPAM), and [[Peritoneal mucinous carcinomatosis]] (PMCA).
==Causes==
==Causes==
Pseudomyxoma peritonei is caused by a pre-existing [[intraperitoneal]] [[mucinous]] [[neoplasm]]. The ''K-Ras'' and [[P53 gene|''p53'' genes]] may be involved in the [[oncogenesis]].<ref name="pmid28280620">{{cite journal |vauthors=Borazanci E, Millis SZ, Kimbrough J, Doll N, Von Hoff D, Ramanathan RK |title=Potential actionable targets in appendiceal cancer detected by immunohistochemistry, fluorescent in situ hybridization, and mutational analysis |journal=J Gastrointest Oncol |volume=8 |issue=1 |pages=164–172 |date=February 2017 |pmid=28280620 |pmc=5334061 |doi=10.21037/jgo.2017.01.14 |url=}}</ref>
Pseudomyxoma peritonei is caused by a pre-existing [[intraperitoneal]] [[mucinous]] [[neoplasm]]. The ''K-Ras'' and [[P53 gene|''p53'' genes]] may be involved in the [[oncogenesis]].


==Differentiating Pseudomyxoma peritonei from other Diseases==
==Differentiating Pseudomyxoma peritonei from other Diseases==
Differential diagnosis of pseudomyxoma peritonei include peritoneal carcinomatosis without mucinous ascites, peritoneal sarcomatosis, [[Peritonitis]], peritoneal [[mesothelioma|mesothelioma.]]<ref name="LevyShaw2009">{{cite journal|last1=Levy|first1=Angela D.|last2=Shaw|first2=Janet C.|last3=Sobin|first3=Leslie H.|title=Secondary Tumors and Tumorlike Lesions of the Peritoneal Cavity: Imaging Features with Pathologic Correlation|journal=RadioGraphics|volume=29|issue=2|year=2009|pages=347–373|issn=0271-5333|doi=10.1148/rg.292085189}}</ref>
Differential diagnosis of pseudomyxoma peritonei include peritoneal carcinomatosis without mucinous ascites, peritoneal sarcomatosis, [[Peritonitis]], peritoneal [[mesothelioma|mesothelioma.]]


==Epidemiology and Demographics==
==Epidemiology and Demographics==
The [[incidence]] of pseudomyxoma peritonei is approximately 0.1 per 100,000 individuals worldwide. Females are more commonly affected with pseudomyxoma peritonei than males. The median age at diagnosis is 50 years.<ref name="pmid25929336">{{cite journal |vauthors=Roberts DL, O'Dwyer ST, Stern PL, Renehan AG |title=Global gene expression in pseudomyxoma peritonei, with parallel development of two immortalized cell lines |journal=Oncotarget |volume=6 |issue=13 |pages=10786–800 |date=May 2015 |pmid=25929336 |pmc=4484419 |doi=10.18632/oncotarget.3198 |url=}}</ref><ref name="pmid25343082">{{cite journal |vauthors=Zhong Y, Deng M, Xu R, Kokudo N, Tang W |title=Pseudomyxoma peritonei as an intractable disease and its preoperative assessment to help improve prognosis after surgery: A review of the literature |journal=Intractable Rare Dis Res |volume=1 |issue=3 |pages=115–21 |date=August 2012 |pmid=25343082 |pmc=4204597 |doi=10.5582/irdr.2012.v1.3.115 |url=}}</ref>
The [[incidence]] of pseudomyxoma peritonei is approximately 0.1 per 100,000 individuals worldwide. [[Female|Females]] are more commonly affected with pseudomyxoma peritonei than [[Male|males]]. The median age at diagnosis is 50 years.


==Risk Factors==
==Risk Factors==
Line 24: Line 24:


==Natural History, Complications and Prognosis==
==Natural History, Complications and Prognosis==
Patients with pseudomyxoma peritonei may develop abdominal or pelvic pain, [[bloating]], [[abdominal distension]], [[weight change]], and [[infertility]]. [[Prognosis]] is generally good and the 10-year [[Survival rates|survival rate]] of patients with pseudomyxoma peritonei is approximately 63%.Overall risk of complications after [[surgery]] such as [[urinary tract]] involvement due to [[tumor]] seeding in pelvis is very low.<ref name="pmid16353186">{{cite journal |vauthors=Smeenk RM, Bex A, Verwaal VJ, Horenblas S, Zoetmulder FA |title=Pseudomyxoma peritonei and the urinary tract: involvement and treatment related complications |journal=J Surg Oncol |volume=93 |issue=1 |pages=20–3 |date=January 2006 |pmid=16353186 |doi=10.1002/jso.20427 |url=}}</ref><ref name="pmid21304299">{{cite journal |vauthors=Youssef H, Newman C, Chandrakumaran K, Mohamed F, Cecil TD, Moran BJ |title=Operative findings, early complications, and long-term survival in 456 patients with pseudomyxoma peritonei syndrome of appendiceal origin |journal=Dis. Colon Rectum |volume=54 |issue=3 |pages=293–9 |date=March 2011 |pmid=21304299 |doi=10.1007/DCR.0b013e318202f026 |url=}}</ref><ref name="pmid22614976">{{cite journal |vauthors=Chua TC, Moran BJ, Sugarbaker PH, Levine EA, Glehen O, Gilly FN, Baratti D, Deraco M, Elias D, Sardi A, Liauw W, Yan TD, Barrios P, Gómez Portilla A, de Hingh IH, Ceelen WP, Pelz JO, Piso P, González-Moreno S, Van Der Speeten K, Morris DL |title=Early- and long-term outcome data of patients with pseudomyxoma peritonei from appendiceal origin treated by a strategy of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy |journal=J. Clin. Oncol. |volume=30 |issue=20 |pages=2449–56 |date=July 2012 |pmid=22614976 |doi=10.1200/JCO.2011.39.7166 |url=}}</ref>
Patients with pseudomyxoma peritonei may develop [[Abdominal pain|abdominal or pelvic pain]], [[bloating]], [[abdominal distension]], [[weight change]], and [[infertility]]. [[Prognosis]] is generally good and the 10-year [[Survival rates|survival rate]] of patients with pseudomyxoma peritonei is approximately 63%.Overall risk of [[complications]] after [[surgery]] such as [[urinary tract]] involvement due to [[tumor]] seeding in [[pelvis]] is very low.


==History and Symptoms==
==History and Symptoms==
Symptoms of pseudomyxoma peritonei include:[[abdominal pain]], [[bloating]], [[abdominal distention]], [[Shortness of breath]], [[Weight change]], [[Menstrual irregularities]] in women.<ref name="pmid30250743">{{cite journal |vauthors=Wambura C, Jusabani A, Sherman O, Surani S |title=Pseudomyxoma pleurii and peritonei secondary to sigmoid colon adenocarcinoma: a rare clinico-pathologico-radiological presentation |journal=Oxf Med Case Reports |volume=2018 |issue=10 |pages=omy057 |date=October 2018 |pmid=30250743 |pmc=6142713 |doi=10.1093/omcr/omy057 |url=}}</ref>
Symptoms of pseudomyxoma peritonei include: [[abdominal pain]], [[bloating]], [[abdominal distention]], [[Shortness of breath]], [[Weight change]], [[Menstrual irregularities]] in women.


==Physical Examination==
==Physical Examination==
Common physical examination findings of pseudomyxoma peritonei include: [[Abdominal tenderness]], [[Abdominal distention]].<ref name="pmid30250743">{{cite journal |vauthors=Wambura C, Jusabani A, Sherman O, Surani S |title=Pseudomyxoma pleurii and peritonei secondary to sigmoid colon adenocarcinoma: a rare clinico-pathologico-radiological presentation |journal=Oxf Med Case Reports |volume=2018 |issue=10 |pages=omy057 |date=October 2018 |pmid=30250743 |pmc=6142713 |doi=10.1093/omcr/omy057 |url=}}</ref>
Common physical examination findings of pseudomyxoma peritonei include: [[Abdominal tenderness]], [[Abdominal distention]].


==Laboratory Findings==
==Laboratory Findings==
The laboratory findings associated with pseudomyxoma peritonei include: increased levels of [[tumor markers]] such as [[carcinoembryonic antigen]] (CEA), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 125 ([[CA125]]).<ref name="AminiMasoumi-Moghaddam2014">{{cite journal|last1=Amini|first1=Afshin|last2=Masoumi-Moghaddam|first2=Samar|last3=Ehteda|first3=Anahid|last4=Morris|first4=David|title=Secreted mucins in pseudomyxoma peritonei: pathophysiological significance and potential therapeutic prospects|journal=Orphanet Journal of Rare Diseases|volume=9|issue=1|year=2014|pages=71|issn=1750-1172|doi=10.1186/1750-1172-9-71}}</ref>
The laboratory findings associated with pseudomyxoma peritonei include: increased levels of [[tumor markers]] such as [[carcinoembryonic antigen]] (CEA), [[CA 19-9|carbohydrate antigen 19-9 (CA19-9)]], [[CA-125|carbohydrate antigen 125]] ([[CA125]]).


==CT==
==CT==
Findings on abdominal [[CT scan]] of patients with pseudomyxoma peritonei include: accumulation of fluid throughout the [[peritoneum]], [[omentum]] and [[mesentery]] seen as low attenuation [[mucin]] depositis on [[CT scan]], scalloping of [[visceral]] organs.<ref name="pmid22147976">{{cite journal |vauthors=Lee NK, Kim S, Kim HS, Jeon TY, Kim GH, Kim DU, Park DY, Kim TU, Kang DH |title=Spectrum of mucin-producing neoplastic conditions of the abdomen and pelvis: cross-sectional imaging evaluation |journal=World J. Gastroenterol. |volume=17 |issue=43 |pages=4757–71 |date=November 2011 |pmid=22147976 |pmc=3229624 |doi=10.3748/wjg.v17.i43.4757 |url=}}</ref>
Findings on abdominal [[CT scan]] of patients with pseudomyxoma peritonei include: accumulation of [[fluid]] throughout the [[peritoneum]], [[omentum]] and [[mesentery]] seen as low [[attenuation]] [[mucin]] depositis on [[CT scan]], scalloping of [[visceral]] organs.


==MRI==
==MRI==
On abdominal [[MRI]], pseudomyxoma peritonei is characterized by a mass which is hypointense on T1-weighted [[MRI]] and hyperintense on T2-weighted MRI, it can further clarify the [[cystic]] structure of mass.<ref name="pmid26494720">{{cite journal |vauthors=Wrafter PF, Connelly T, Khan JS, Joyce WP |title=Pseudomyxoma peritonei diagnosed 19 years after appendicectomy |journal=BMJ Case Rep |volume=2015 |issue= |pages= |date=October 2015 |pmid=26494720 |pmc=4620202 |doi=10.1136/bcr-2015-211706 |url=}}</ref>
On abdominal [[MRI]], pseudomyxoma peritonei is characterized by a [[mass]] which is hypointense on T1-weighted [[MRI]] and hyperintense on T2-weighted [[MRI]], it can further clarify the [[cystic]] structure of [[mass]].


==Ultrasound==
==Ultrasound==
Abdominal [[ultrasound]] scan may be helpful in the diagnosis of pseudomyxoma peritonei. Finding on [[ultrasound]] scan suggestive of pseudomyxoma peritonei are echogenic peritoneal masses or [[ascites]] with echogenic particles which do not move.<ref name="pmid11952975">{{cite journal |vauthors=Khan S, Patel AG, Jurkovic D |title=Incidental ultrasound diagnosis of pseudomyxoma peritonei in an asymptomatic woman |journal=Ultrasound Obstet Gynecol |volume=19 |issue=4 |pages=410–2 |date=April 2002 |pmid=11952975 |doi=10.1046/j.1469-0705.2002.00611.x |url=}}</ref><ref name="pmid26564459">{{cite journal |vauthors=Qi ZH, Cai S, Li JC, L K, Zhang Y, Xiao MS, Su N |title=[Ultrasonographic Features of Pseudomyxoma Peritonei and TheirComparison with Computed Tomographic Findings] |language=Chinese |journal=Zhongguo Yi Xue Ke Xue Yuan Xue Bao |volume=37 |issue=4 |pages=424–9 |date=August 2015 |pmid=26564459 |doi=10.3881/j.issn.1000-503X.2015.04.010 |url=}}</ref><ref name="pmid23980216">{{cite journal |vauthors=Li Y, Guo A, Tang J, Wang L, Wang J, Yu D |title=Role of preoperative sonography in the diagnosis and pathologic staging of pseudomyxoma peritonei |journal=J Ultrasound Med |volume=32 |issue=9 |pages=1565–70 |date=September 2013 |pmid=23980216 |doi=10.7863/ultra.32.9.1565 |url=}}</ref>
Abdominal [[ultrasound]] scan may be helpful in the diagnosis of pseudomyxoma peritonei. Finding on [[ultrasound]] scan suggestive of pseudomyxoma peritonei are [[echogenic]] [[Peritoneal|peritoneal masses]] or [[ascites]] with echogenic particles which do not move.


==Medical Therapy==
==Medical Therapy==
The predominant [[therapy]] for pseudomyxoma peritonei is [[Resection|surgical resection]] and [[debulking]]. Supportive therapy for pseudomyxoma peritonei includes [[chemotherapy]] which can be used as [[Adjuvant|adjuvant treatment]]. The treatment of choice is complete tumor excision named cytoreductive surgery (CRS) combined with [[Hyperthermic intraperitoneal chemoperfusion]] (HIPEC).<ref name="pmid28540829">{{cite journal |vauthors=Mittal R, Chandramohan A, Moran B |title=Pseudomyxoma peritonei: natural history and treatment |journal=Int J Hyperthermia |volume=33 |issue=5 |pages=511–519 |date=August 2017 |pmid=28540829 |doi=10.1080/02656736.2017.1310938 |url=}}</ref><ref name="pmid17197972">{{cite journal |vauthors=Smeenk RM, Verwaal VJ, Antonini N, Zoetmulder FA |title=Survival analysis of pseudomyxoma peritonei patients treated by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy |journal=Ann. Surg. |volume=245 |issue=1 |pages=104–9 |date=January 2007 |pmid=17197972 |pmc=1867935 |doi=10.1097/01.sla.0000231705.40081.1a |url=}}</ref>
The predominant [[therapy]] for pseudomyxoma peritonei is [[Resection|surgical resection]] and [[debulking]]. Supportive therapy for pseudomyxoma peritonei includes [[chemotherapy]] which can be used as [[Adjuvant|adjuvant treatment]]. The treatment of choice is [[Excision|complete tumor excision]] named cytoreductive surgery (CRS) combined with [[Hyperthermic intraperitoneal chemoperfusion]] (HIPEC).


==Surgery==
==Surgery==
[[Surgery]] is the mainstay of treatment for pseudomyxoma peritonei. The feasibility of [[surgery]] depends on the stage of pseudomyxoma peritonei at diagnosis.<ref name="AminiMasoumi-Moghaddam2014">{{cite journal|last1=Amini|first1=Afshin|last2=Masoumi-Moghaddam|first2=Samar|last3=Ehteda|first3=Anahid|last4=Morris|first4=David|title=Secreted mucins in pseudomyxoma peritonei: pathophysiological significance and potential therapeutic prospects|journal=Orphanet Journal of Rare Diseases|volume=9|issue=1|year=2014|pages=71|issn=1750-1172|doi=10.1186/1750-1172-9-71}}</ref><ref name="Harmon_2005">{{cite journal |author=Harmon R, Sugarbaker P |title=Prognostic indicators in peritoneal carcinomatosis from gastrointestinal cancer |journal=Int Semin Surg Oncol |volume=2 |issue=1 |pages=3 |year=2005 |url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=549516 |pmid=15701175}}</ref>
[[Surgery]] is the mainstay of treatment for pseudomyxoma peritonei. The feasibility of [[surgery]] depends on the stage of pseudomyxoma peritonei at diagnosis.  
== References ==
{{Reflist|2}}


[[Category:Types of cancer]]
[[Category:Types of cancer]]

Latest revision as of 20:14, 1 April 2019

Pseudomyxoma peritonei Microchapters

Home

Patient Information

Overview

Historical Perspective

Pathophysiology

Causes

Differentiating Pseudomyxoma peritonei from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

CT

MRI

Ultrasound

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Pseudomyxoma peritonei overview On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Pseudomyxoma peritonei overview

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Pseudomyxoma peritonei overview

CDC on Pseudomyxoma peritonei overview

Pseudomyxoma peritonei overview in the news

Blogs on Pseudomyxoma peritonei overview

Directions to Hospitals Treating Pseudomyxoma peritonei

Risk calculators and risk factors for Pseudomyxoma peritonei overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Nima Nasiri, M.D.[2]

Overview

Pseudomyxoma peritonei is a very rare tumor characterized by the presence of abundant mucus in the abdominal cavity, consisting of intraperitoneal mucinous tumors and ascites, most commonly arising from mucinous tumors of the appendix, however, the ovary or the colon may be the primary site of origin. The tumor is not harmful by itself, but the mucus accumulation in abdominal cavity compresses vital organs such as spleen, kidney, colon. On 1842, Carl F. Rokitansky described the first case of pseudomyxoma peritonei. Pseudomyxoma peritonei may be divided into two pathological subtypes with different etiology and prognosis, these two subtypes are peritoneal adenomucinosis and peritoneal mucinous carcinoma. The K-Ras and p53 genes are involved in the oncogenesis. Pseudomyxoma peritonei must be differentiated from peritoneal carcinomatosis without mucinous ascites, peritoneal sarcomatosis, and tuberculosis peritonitis. The incidence of pseudomyxoma peritonei is approximately 0.1 person per 100,000 individuals worldwide. Females are more commonly affected with pseudomyxoma peritonei than males. The median age at diagnosis is 50 years. There are no established risk factors for pseudomyxoma peritonei. Patients with pseudomyxoma peritonei may develop abdominal or pelvic pain, bloating, abdominal distension, weight change, and infertility symptoms if left untreated. Common physical examination findings of pseudomyxoma peritonei include abdominal tenderness, abdominal distention. On abdominal CT scan, pseudomyxoma peritonei is characterized by low attenuation, loculated ascitic mucinous fluid in the peritoneum, omentum and mesentery with scalloping of visceral surfaces of the liver. On abdominal MRI, pseudomyxoma peritonei is characterized by a mass which is hypointense on T1-weighted MRI and hyperintense on T2-weighted MRI. Finding on ultrasound scan suggestive of pseudomyxoma peritonei are echogenic peritoneal masses or ascites which is not mobile. Cytoreductive surgery combined with hyperthermic intraperitoneal chemoperfusion is the optimal way of treatment for pseudomyxoma peritonei.

Historical Perspective

The first case of pseudomyxoma peritonei was described by Carl F. Rokitansky in 1842.

Pathophysiology

Pseudomyxoma peritonei is a rare poorly understood neoplasm which may be divided into two pathological subtypes: Disseminated peritoneal adenomucinosis (DPAM), and Peritoneal mucinous carcinomatosis (PMCA).

Causes

Pseudomyxoma peritonei is caused by a pre-existing intraperitoneal mucinous neoplasm. The K-Ras and p53 genes may be involved in the oncogenesis.

Differentiating Pseudomyxoma peritonei from other Diseases

Differential diagnosis of pseudomyxoma peritonei include peritoneal carcinomatosis without mucinous ascites, peritoneal sarcomatosis, Peritonitis, peritoneal mesothelioma.

Epidemiology and Demographics

The incidence of pseudomyxoma peritonei is approximately 0.1 per 100,000 individuals worldwide. Females are more commonly affected with pseudomyxoma peritonei than males. The median age at diagnosis is 50 years.

Risk Factors

There are no established risk factors for pseudomyxoma peritonei.

Natural History, Complications and Prognosis

Patients with pseudomyxoma peritonei may develop abdominal or pelvic pain, bloating, abdominal distension, weight change, and infertility. Prognosis is generally good and the 10-year survival rate of patients with pseudomyxoma peritonei is approximately 63%.Overall risk of complications after surgery such as urinary tract involvement due to tumor seeding in pelvis is very low.

History and Symptoms

Symptoms of pseudomyxoma peritonei include: abdominal pain, bloating, abdominal distention, Shortness of breath, Weight change, Menstrual irregularities in women.

Physical Examination

Common physical examination findings of pseudomyxoma peritonei include: Abdominal tenderness, Abdominal distention.

Laboratory Findings

The laboratory findings associated with pseudomyxoma peritonei include: increased levels of tumor markers such as carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 125 (CA125).

CT

Findings on abdominal CT scan of patients with pseudomyxoma peritonei include: accumulation of fluid throughout the peritoneum, omentum and mesentery seen as low attenuation mucin depositis on CT scan, scalloping of visceral organs.

MRI

On abdominal MRI, pseudomyxoma peritonei is characterized by a mass which is hypointense on T1-weighted MRI and hyperintense on T2-weighted MRI, it can further clarify the cystic structure of mass.

Ultrasound

Abdominal ultrasound scan may be helpful in the diagnosis of pseudomyxoma peritonei. Finding on ultrasound scan suggestive of pseudomyxoma peritonei are echogenic peritoneal masses or ascites with echogenic particles which do not move.

Medical Therapy

The predominant therapy for pseudomyxoma peritonei is surgical resection and debulking. Supportive therapy for pseudomyxoma peritonei includes chemotherapy which can be used as adjuvant treatment. The treatment of choice is complete tumor excision named cytoreductive surgery (CRS) combined with Hyperthermic intraperitoneal chemoperfusion (HIPEC).

Surgery

Surgery is the mainstay of treatment for pseudomyxoma peritonei. The feasibility of surgery depends on the stage of pseudomyxoma peritonei at diagnosis.


Template:WikiDoc Sources