What is the treatment for Pseudomyxoma peritonitis?

Treatment of Pseudomyxoma Peritonei

The definitive treatment for pseudomyxoma peritonei is complete cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC), which should be performed at specialized centers with expertise in this rare condition. 1

Initial Management Strategy

When Infection is Present (Superinfected PMP)

• Use a staged approach when pseudomyxoma peritonei presents with superinfection, which is a rare but documented presentation 2
• First stage: Control the intraabdominal sepsis with broad-spectrum antibiotics covering Gram-negative bacteria and anaerobes, with or without resection of the primary tumor 2
• Initiate empiric antibiotics immediately covering mixed aerobic/anaerobic flora, as source control timing is critical in surgical infections 3
• Second stage: After patient rehabilitation and infection clearance, proceed to definitive CRS with HIPEC 2

Surgical Source Control Principles

• Perform thorough surgical debulking as the cornerstone of treatment, though complete resection at initial operation is rarely feasible except in truly benign lesions 4, 5
• Plan for a complex, time-consuming procedure that may require cooperation between multiple surgical specialists 5
• Conduct accurate preoperative assessment using MDCT radiological scoring, which has 94% sensitivity and 81% specificity for predicting resectability and survival 1
• Source control should be achieved as soon as possible once the patient is stabilized, as delayed or incomplete procedures severely worsen outcomes in critically ill patients 3

Definitive Treatment: CRS with HIPEC

Surgical Approach

• Complete cytoreductive surgery involves removal of all visible mucinous deposits from peritoneal surfaces and omentum 5, 1
• Combine with HIPEC during or immediately after the cytoreductive procedure 5
• Expect 5-year overall survival between 23-82% depending on disease grade and completeness of cytoreduction 1
• Anticipate major complications in up to 24% of cases 1

Patient Selection Criteria

• Reserve CRS with HIPEC for appropriately staged patients who can tolerate this extensive procedure 1
• Use preoperative tumor markers to establish prognosis and guide treatment decisions 1
• Consider the WHO 2010 classification which divides PMP into low-grade and high-grade mucinous carcinoma, as this impacts prognosis 6

Management of Recurrent Disease

• Anticipate recurrence as the majority of patients will eventually experience disease progression despite optimal treatment 5
• Reoperation is always indicated for symptomatic recurrence due to the low morbidity and slow growth characteristics of the tumor 4
• Debulking operations provide considerable benefit even when complete resection is not achievable, particularly for managing bowel obstruction 4

Adjuvant Therapy Considerations

• Intraperitoneal chemotherapy has anecdotal support though evidence remains limited 5
• Systemic chemotherapy results vary widely with some patients achieving tumor-free intervals of several years, while others show minimal response 4
• Continue treatment until resolution of physiological abnormalities in patients who undergo adequate source control 3

Critical Pitfalls to Avoid

• Do not delay surgical intervention once infection is controlled, as timing of source control directly impacts mortality 3
• Do not attempt definitive surgery during active infection - use the staged approach to optimize outcomes 2
• Do not perform this surgery at non-specialized centers - the rarity and complexity of PMP requires dedicated multidisciplinary teams and pathologists experienced with this entity 6
• Do not confuse with other forms of peritonitis - PMP is a neoplastic process requiring oncologic surgical principles, not just infection management 6, 5