Overview
Definition:
Cytoreductive surgery (CRS) is an aggressive surgical approach aimed at removing all visible cancerous implants from the peritoneal surface
Peritonectomy is the detailed dissection and excision of these peritoneal metastases
It is often combined with hyperthermic intraperitoneal chemotherapy (HIPEC) to eradicate microscopic disease.
Epidemiology:
Peritoneal carcinomatosis is a common manifestation of advanced gastrointestinal and gynecological malignancies, including epithelial ovarian cancer, colorectal cancer, gastric cancer, appendiceal cancer, and pseudomyxoma peritonei
The incidence varies significantly based on primary malignancy and stage.
Clinical Significance:
CRS and HIPEC represent a paradigm shift in the management of peritoneal surface malignancy, offering a chance for long-term survival and even cure in selected patients
It is a complex multidisciplinary intervention requiring expert surgical skill and careful patient selection.
Indications
Patient Selection:
Careful patient selection is paramount
patients must have a performance status suitable for extensive surgery and anesthesia
Absence of extra-abdominal metastases and disease confined to the peritoneum are key criteria.
Primary Malignancies:
Epithelial ovarian cancer (FIGO stage III-IV)
Peritoneal carcinomatosis from colorectal cancer
Gastric cancer with peritoneal involvement
Appendiceal cancer with pseudomyxoma peritonei
Other rare peritoneal surface malignancies.
Disease Burden:
The extent of peritoneal disease is assessed using the Peritoneal Cancer Index (PCI), a standardized scoring system
A PCI of 0-20 is generally considered amenable to complete cytoreduction, though criteria can vary.
Previous Treatment:
Patients who have failed systemic chemotherapy but still have resectable peritoneal disease may be candidates
Repeat CRS can be considered in select cases of recurrence.
Preoperative Preparation
Multidisciplinary Evaluation:
Involves surgeons, medical oncologists, radiologists, pathologists, anesthetists, and nutritionists
Thorough discussion of risks, benefits, and alternatives.
Imaging Assessment:
CT scan of the abdomen and pelvis with contrast is essential to assess disease burden, identify potential resectable lesions, and rule out extra-peritoneal spread
MRI may be used for specific organ involvement.
Nutritional Optimization:
Patients are optimized nutritionally, often with pre-operative supplementation, to improve wound healing and recovery from major surgery.
Anesthesia Considerations:
Requires specialized anesthetic management due to prolonged operative time, large fluid shifts, and potential hemodynamic instability
Central venous access, arterial lines, and invasive monitoring are standard.
Procedure Steps
Exploratory Laparotomy:
A midline laparotomy is typically performed to fully assess the extent of peritoneal disease and calculate the Peritoneal Cancer Index (PCI).
Peritonectomy Techniques:
This involves meticulous stripping of the peritoneum from abdominal and pelvic organs
Key techniques include:
- Omentectomy: Removal of the omentum.
- Peritonectomy of the Diaphragm: Excision of diaphragmatic peritoneum, often using specialized instruments.
- Peritonectomy of the Pelvic Peritoneum: Including peritoneum of the pouch of Douglas and rectovesical pouch.
- Peritonectomy of the Abdominal Wall: Stripping of the parietal peritoneum from the anterior abdominal wall.
- Visceral Peritonectomy: Excision of peritoneum from the surfaces of organs like the stomach, liver, spleen, small bowel, colon, and bladder.
- Organ Resection: If involved, resection of organs like ovaries, fallopian tubes, uterus, spleen, gallbladder, parts of the colon, stomach, or pancreas may be necessary.
Cytoreduction Goal:
The aim is to achieve a complete or near-complete cytoreduction (CC-0 or CC-1), meaning no visible tumor nodules larger than 5mm remain.
Hyperthermic Intraperitoneal Chemotherapy Hipec:
After meticulous macroscopic tumor removal, heated chemotherapy (e.g., mitomycin C, oxaliplatin, cisplatin) is instilled into the abdominal cavity at 41-43°C for 60-90 minutes to kill microscopic residual disease
Techniques include open (coliseum) and closed lavage methods.
Postoperative Care
Intensive Care Unit Management:
Patients are typically admitted to the ICU post-operatively for close monitoring of hemodynamics, fluid balance, respiratory status, and pain control.
Pain Management:
Aggressive pain management, often with epidural anesthesia or patient-controlled analgesia (PCA), is crucial for patient comfort and early mobilization.
Nutritional Support:
Initiation of enteral or parenteral nutrition as needed
Gradual advancement of oral diet is guided by bowel function.
Monitoring For Complications:
Close monitoring for signs of infection, anastomotic leak, ileus, fluid/electrolyte imbalances, and thromboembolic events
Daily abdominal examinations and laboratory tests.
Complications
Early Complications:
Gastrointestinal complications: ileus, anastomotic leak, fistula formation, bowel obstruction
Wound complications: infection, dehiscence
Sepsis
Hemodynamic instability
Fluid and electrolyte imbalances
Acute kidney injury
Bone marrow suppression from HIPEC.
Late Complications:
Adhesions leading to bowel obstruction
Inguinal hernias
Chronic pain
Malabsorption
Infertility
Secondary malignancies (rare).
Prevention Strategies:
Meticulous surgical technique to avoid bowel injury
Careful fluid management
Prophylactic antibiotics
Early mobilization
Judicious use of HIPEC agents
Close post-operative surveillance.
Prognosis
Factors Affecting Prognosis:
Completeness of cytoreduction (CC-0/CC-1 is critical)
Peritoneal Cancer Index (PCI) at diagnosis
Histological type of cancer (e.g., mucinous adenocarcinoma of appendix has a better prognosis)
Primary tumor characteristics
Patient performance status.
Outcomes:
For selected patients with ovarian cancer and pseudomyxoma peritonei, CRS + HIPEC can achieve 5-year survival rates exceeding 50-70%
For colorectal carcinomatosis, survival rates are generally lower but still significantly improved compared to palliative care.
Follow Up:
Regular follow-up with clinical examination, tumor marker monitoring (e.g., CA-125, CEA), and imaging (CT scans) every 3-6 months for the first 2-3 years, then annually
Surveillance aims to detect recurrence early for potential re-intervention.
Key Points
Exam Focus:
Understand the indications for CRS/HIPEC, especially in ovarian and appendiceal cancers
Differentiate between peritonectomy techniques for different abdominal regions
Recognize the importance of PCI and completeness of cytoreduction (CC score)
Recall common HIPEC agents and their rationale.
Clinical Pearls:
Complete macroscopic tumor removal is the cornerstone of successful CRS
The anesthesiologist is a vital member of the surgical team
Meticulous attention to detail is required during peritoneal stripping
Consider the potential for significant fluid shifts and electrolyte disturbances.
Common Mistakes:
Inadequate patient selection leading to poor outcomes or excessive morbidity
Incomplete cytoreduction
Overly aggressive surgery in the presence of extra-abdominal disease
Inadequate attention to perioperative fluid management and monitoring.