Understanding Pseudomyxoma Peritonei: Symptoms and Treatment

Pseudomyxoma peritonei (PMP) is a rare and complex condition characterized by the presence of mucinous tumours primarily within the peritoneal cavity. 

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What is Pseudomyxoma Peritonei?

Pseudomyxoma peritonei is a clinical condition wherein mucin-producing tumour cells proliferate within the abdominal cavity, leading to the accumulation of mucinous ascites. This condition predominantly originates from appendiceal neoplasms but can also arise from ovarian, colorectal, and pancreatic origins.

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Causes of Pseudomyxoma Peritonei

Appendiceal Neoplasms

The most common cause of PMP is a mucinous tumour of the appendix, particularly a low-grade appendiceal mucinous neoplasm (LAMN). These tumours rupture and disseminate mucin-producing cells throughout the peritoneal cavity.

Ovarian Tumors

Ovarian mucinous tumours are another potential source of PMP. These tumours may be primary or metastatic, often complicating the diagnostic process.

Other Origins

In rare cases, PMP may originate from mucinous tumours of the pancreas or colon, further complicating its aetiology.

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Symptoms of Pseudomyxoma Peritonei

Abdominal Distension

One of the hallmark symptoms of PMP is progressive abdominal distension caused by the accumulation of mucinous fluid within the peritoneal cavity.

Abdominal Pain

Patients may experience varying degrees of abdominal pain, often exacerbated by the increasing pressure of the mucinous deposits on abdominal structures.

Changes in Bowel Habits

Altered bowel movements, including constipation and diarrhoea, can occur due to the mechanical obstruction caused by the mucinous deposits.

Weight Changes

Unintentional weight gain or loss can be observed in patients with PMP, often correlating with the extent of the mucinous accumulation.

Hernias

The increased intra-abdominal pressure may lead to the development of hernias, particularly umbilical and inguinal hernias.

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Diagnosing Pseudomyxoma Peritonei

Radiology and Imaging

CT Scans

Computed tomography (CT) scans are instrumental in diagnosing PMP. They provide detailed images of the mucinous deposits and their distribution within the peritoneal cavity.

MRI

Magnetic resonance imaging (MRI) can be utilized to characterize the mucinous tumours further and assess their relationship with adjacent structures.

Biopsy

A percutaneous or surgical biopsy of the mucinous deposits is often necessary to confirm the diagnosis and determine the tumour's histological subtype.

Serum Markers

Elevated levels of tumour markers such as carcinoembryonic antigen (CEA) and cancer antigen 19-9 (CA 19-9) may support the diagnosis but are not definitive.

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Types of Pseudomyxoma Peritonei

Low-Grade PMP

Low-grade PMP, also known as disseminated peritoneal adenomucinosis (DPAM), is characterized by a relatively indolent course and a better prognosis compared to high-grade PMP.

High-Grade PMP

High-grade PMP, also known as peritoneal mucinous carcinomatosis (PMCA), exhibits more aggressive behaviour and a higher propensity for invasion and metastasis.

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Treatment Options for Pseudomyxoma Peritonei

Cytoreductive Surgery (CRS)

Cytoreductive surgery aims to remove as much of the visible tumour burden as possible. This often involves extensive surgical procedures, including peritonectomy and organ resection.

Hyperthermic Intraperitoneal Chemotherapy (HIPEC)

Following cytoreductive surgery, HIPEC is employed to deliver heated chemotherapy directly into the peritoneal cavity. This technique enhances the penetration of chemotherapeutic agents into the residual tumour cells, improving treatment efficacy.

Systemic Chemotherapy

Systemic chemotherapy may be used as an adjunct to surgical interventions, particularly in cases of high-grade PMP or when complete cytoreduction is not achievable.

Palliative Care

In advanced cases where curative treatment is not feasible, palliative care focuses on symptom management and improving quality of life. This may involve drainage of ascites, pain management, and nutritional support.

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Prognosis and Life Expectancy

With Surgery

The prognosis of PMP significantly improves with timely and appropriate surgical intervention. Patients undergoing complete cytoreduction and HIPEC have a better overall survival rate.

Without Surgery

Without surgical intervention, the prognosis of PMP is generally poor. The progressive accumulation of mucinous ascites leads to severe complications, including bowel obstruction, respiratory difficulties, and, ultimately, a significant reduction in life expectancy.

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Prevention and Early Detection

Regular Monitoring

Individuals with a known history of appendiceal or ovarian mucinous tumours should undergo regular monitoring and imaging to detect any early signs of PMP.

Genetic Counseling

For those with a family history of mucinous tumours, genetic counseling and testing may help identify potential risks and facilitate early intervention.

Symptom Awareness

Raising awareness about the symptoms of PMP among at-risk populations can lead to earlier diagnosis and improved treatment outcomes.