Understanding Peritonectomy: A Comprehensive Review for Surgeons

Peritonectomy is a complex and specialized surgical procedure aimed at removing the peritoneum, a layer of tissue that lines the abdominal cavity and covers most of the abdominal organs. This procedure is typically performed in cases of peritoneal carcinomatosis, where cancer has spread to the peritoneal surfaces. Understanding the nuances of this surgery, from indications to postoperative care, is crucial for any surgeon involved in its execution. This article will delve into the intricate details of peritonectomy, providing a comprehensive overview for surgeons.

Indications for Peritonectomy

Peritonectomy is primarily indicated for patients with peritoneal surface malignancies. These malignancies often arise from primary cancers, such as colorectal cancer, ovarian cancer, appendiceal cancer, and pseudomyxoma peritonei. The procedure is most effective when the disease is confined to the peritoneal surfaces and has not metastasized to distant organs.

• Peritoneal Carcinomatosis: This is the most common indication for peritonectomy. It involves the widespread distribution of cancerous cells throughout the peritoneum, often secondary to gastrointestinal or gynecological malignancies.
• Pseudomyxoma Peritonei: A rare condition characterized by the production of mucinous ascites, often originating from the appendix. Peritonectomy is performed to remove mucin-producing tumor cells.
• Mesothelioma: A cancer of the mesothelial cells lining the peritoneum. Peritonectomy, combined with other treatments like hyperthermic intraperitoneal chemotherapy (HIPEC), can be part of a multimodal treatment strategy.
• Recurrent Ovarian Cancer: For patients with recurrent ovarian cancer confined to the peritoneum, peritonectomy offers a potential for extended survival when combined with other treatments.

Preoperative Evaluation

A thorough preoperative evaluation is essential to determine the suitability of a patient for peritonectomy. This includes:

• Imaging Studies: CT scans, MRI, and PET scans are crucial for assessing the extent of peritoneal disease and detecting any extra-abdominal metastasis. The Peritoneal Cancer Index (PCI) is often used to quantify the disease burden and predict the feasibility of complete cytoreduction.
• Laboratory Tests: Comprehensive blood tests, including tumor markers (e.g., CEA, CA-125), liver function tests, and coagulation profiles, are necessary to evaluate the patient's overall health and surgical risk.
• Nutritional Assessment: Malnutrition is common in patients with advanced malignancies. Nutritional status should be optimized before surgery, as poor nutritional status can increase the risk of postoperative complications.
• Cardiopulmonary Evaluation: Given the extensive nature of the surgery, a detailed cardiopulmonary assessment is required, especially in patients with comorbidities. This may include echocardiography, pulmonary function tests, and stress testing.
• Multidisciplinary Consultation: Involving a multidisciplinary team, including oncologists, radiologists, anesthesiologists, and dietitians, is critical in planning the surgery and postoperative care.

Contraindications

Peritonectomy is a highly invasive procedure with significant morbidity. Therefore, careful patient selection is paramount. Contraindications include:

• Widespread Distant Metastasis: Patients with metastases outside the abdominal cavity are generally not candidates for peritonectomy, as the surgery would not provide a survival benefit.
• Poor Performance Status: Patients with a poor performance status (e.g., ECOG performance status 3 or 4) may not tolerate the extensive surgery and its associated recovery period.
• Severe Comorbidities: Conditions such as advanced heart failure, severe chronic obstructive pulmonary disease (COPD), or renal failure may preclude patients from undergoing peritonectomy.
• Extensive Disease Burden: A high Peritoneal Cancer Index (PCI) score may indicate that complete cytoreduction is not feasible, making the surgery less likely to be beneficial.

Surgical Techniques and Steps

Peritonectomy is a multi-step procedure that often involves the removal of multiple peritoneal surfaces and organs. The primary goal is to achieve complete cytoreduction, which involves the removal of all visible tumor masses. The following are key components of the surgical process:

1. Exploration and Staging: The surgery begins with a thorough exploration of the abdominal cavity to confirm the extent of the disease and to ensure there are no contraindications to proceeding with peritonectomy.
2. Omentectomy: Removal of the greater omentum, a common site for peritoneal metastases, is often the first step. The lesser omentum may also be removed if involved.
3. Right and Left Upper Quadrant Peritonectomy: This involves the stripping of the peritoneum from the diaphragmatic surfaces and the paracolic gutters. These areas are frequent sites of tumor involvement, especially in gastrointestinal cancers.
4. Pelvic Peritonectomy: The pelvic peritoneum, including the bladder peritoneum and rectal peritoneum, may be removed if involved. This step often requires concurrent resections, such as a low anterior resection or a total abdominal hysterectomy with bilateral salpingo-oophorectomy in females.
5. Splenectomy and Cholecystectomy: If the spleen or gallbladder is involved, they are resected as part of the cytoreductive effort.
6. Hyperthermic Intraperitoneal Chemotherapy (HIPEC): After the surgical removal of the tumors, the abdominal cavity is often treated with HIPEC. This involves circulating heated chemotherapy drugs within the abdominal cavity to kill any remaining microscopic cancer cells.
7. Reconstruction: Depending on the extent of the resection, bowel anastomosis or ostomy creation may be necessary. Careful attention is given to achieving secure and tension-free anastomoses to reduce the risk of postoperative complications.
8. Closure: The abdomen is carefully closed, often with the placement of drains to monitor for postoperative fluid collections or bleeding.

Postoperative Care

Postoperative management is crucial for the recovery and long-term outcomes of patients undergoing peritonectomy. Key aspects include:

• Intensive Care Monitoring: Due to the extensive nature of the surgery, patients are often monitored in an intensive care unit (ICU) for the first 24-48 hours postoperatively.
• Fluid and Electrolyte Management: Aggressive fluid resuscitation is often required due to the large fluid shifts that occur during surgery. Electrolyte imbalances should be corrected promptly.
• Pain Management: Effective pain control is essential for recovery. Epidural analgesia or patient-controlled analgesia (PCA) is commonly used in the immediate postoperative period.
• Early Mobilization: Encouraging early mobilization can help reduce the risk of complications such as deep vein thrombosis (DVT) and pulmonary embolism (PE).
• Nutritional Support: Enteral feeding is preferred to maintain gut integrity, but parenteral nutrition may be necessary if bowel function is delayed.
• Wound Care: Meticulous wound care is essential to prevent infections, especially in patients who have undergone extensive resections.
• Monitoring for Complications: Common postoperative complications include anastomotic leaks, abscess formation, and hemorrhage. Prompt recognition and management of these complications are critical.

Possible Complications

Peritonectomy is associated with a high risk of complications due to the extensive nature of the surgery. Common complications include:

• Intra-abdominal Abscess: This is a common complication due to the extensive dissection involved. It often requires drainage and antibiotic therapy.
• Anastomotic Leak: Bowel anastomoses are at risk of leaking, leading to peritonitis and sepsis. Management may require reoperation and diversion.
• Bleeding: Significant intraoperative bleeding can occur, necessitating blood transfusions and potentially reoperation.
• Infection: Both surgical site infections and systemic infections are common, requiring aggressive management with antibiotics and supportive care.
• Adhesions: Postoperative adhesions can lead to bowel obstruction, which may require further surgical intervention.

Prognosis and Outcome

The prognosis after peritonectomy depends on several factors, including the primary cancer type, the extent of disease, the success of cytoreduction, and the patient’s overall health. In selected patients, peritonectomy combined with HIPEC has been shown to improve survival, especially in cases of peritoneal carcinomatosis from colorectal cancer and pseudomyxoma peritonei.

• Survival Rates: Five-year survival rates can range from 30% to 60% depending on the disease and the completeness of cytoreduction.
• Quality of Life: While peritonectomy can be life-extending, it is associated with significant morbidity. Patients should be counseled about the potential for a lengthy and challenging recovery.
• Recurrence: Recurrence is common, and ongoing surveillance is necessary. In some cases, repeat surgery or systemic therapy may be required.

Alternative Options

For patients who are not candidates for peritonectomy, alternative treatments include:

• Systemic Chemotherapy: This is the primary treatment for patients with widespread metastatic disease. It may be used alone or in combination with other therapies.
• Palliative Care: In cases where curative treatment is not possible, palliative care focuses on symptom management and quality of life.
• HIPEC without Peritonectomy: In select cases, HIPEC may be performed without extensive cytoreductive surgery, although this is less common.

Recent Advances

Recent advances in peritonectomy and HIPEC include:

• Improved Patient Selection: Advances in imaging and molecular profiling are helping to better identify patients who will benefit most from peritonectomy.
• Minimally Invasive Techniques: There is ongoing research into the use of minimally invasive techniques for performing peritonectomy and HIPEC, which may reduce morbidity and recovery time.
• Enhanced Recovery Protocols: The implementation of enhanced recovery after surgery (ERAS) protocols has been shown to improve outcomes and reduce hospital stays.
• Immunotherapy: There is increasing interest in combining peritonectomy and HIPEC with immunotherapy to enhance the immune response against peritoneal malignancies.

Average Cost

The cost of peritonectomy and HIPEC can vary widely depending on the location, the extent of surgery, and the need for additional treatments. In the United States, the cost can range from $50,000 to $100,000 or more. This cost typically includes preoperative evaluation, surgery, HIPEC, postoperative care, and follow-up. Insurance coverage may vary, and patients should be advised to consult with their providers.