Overview

Definition:
-Peritoneal carcinomatosis (PC) is the diffuse spread of cancer cells throughout the peritoneal cavity, originating from various primary intra-abdominal malignancies
-It significantly impacts prognosis and treatment strategies, often requiring specialized multimodal therapy
-CRS and HIPEC represent a paradigm shift in managing PC, aiming for complete removal of visible tumor and eradication of microscopic disease.
Epidemiology:
-PC is a common presentation for appendiceal, ovarian, gastric, colorectal, and pancreatic cancers, affecting approximately 15-25% of patients with these malignancies at diagnosis
-The incidence of PC is higher in certain subtypes, such as mucinous adenocarcinomas
-Patients with PC generally have a poorer prognosis compared to those with localized disease, with a median survival often measured in months without aggressive treatment.
Clinical Significance:
-Peritoneal carcinomatosis is a major determinant of morbidity and mortality in patients with advanced intra-abdominal cancers
-It can lead to significant symptoms including abdominal distension, pain, nausea, vomiting, ascites, and bowel obstruction, drastically reducing quality of life
-Effective management of PC is crucial for improving survival and symptom control, making CRS and HIPEC vital components of the surgical oncologist's armamentarium for selected patients.

Clinical Presentation

Symptoms:
-Vague abdominal discomfort or pain
-Progressive abdominal distension and bloating
-Nausea and vomiting, especially with oral intake
-Early satiety and loss of appetite
-Unexplained weight loss
-Altered bowel habits, including constipation or diarrhea
-Ascites, leading to shortness of breath and increased abdominal girth
-Symptoms can be insidious and mimic other gastrointestinal conditions, delaying diagnosis.
Signs:
-Palpable abdominal masses or nodules, often diffuse
-Ascites, evidenced by shifting dullness and fluid thrill on physical examination
-Peritoneal signs (tenderness, guarding) if associated with peritoneal inflammation or ischemia
-Cachexia and signs of malnutrition
-Digital rectal examination may reveal nodularity or mass
-Omental caking may be appreciated on palpation.
Diagnostic Criteria:
-There are no strict universally defined diagnostic criteria for PC itself
-diagnosis is primarily based on imaging and histological confirmation
-However, guidelines for patient selection for CRS/HIPEC focus on the absence of extra-abdominal disease, resectability of primary tumor, patient's performance status (ECOG/KPS), and absence of extensive diffuse carcinomatosis in certain organs (e.g., liver)
-The Peritoneal Surface Disease Severity Score (PSDS) and the Peritoneal Cancer Index (PCI) are critical for surgical planning and prognostication.

Diagnostic Approach

History Taking:
-Detailed history of primary cancer type, stage, and previous treatments
-Onset and progression of abdominal symptoms
-Previous surgeries and their outcomes
-Family history of malignancy
-Significant weight loss, anorexia, or early satiety
-History of ascites or bowel obstruction
-Red flags include persistent abdominal pain, unexplained distension, and worsening gastrointestinal symptoms in a patient with a history of intra-abdominal malignancy.
Physical Examination:
-Complete abdominal examination, including inspection for distension and scars, palpation for masses and tenderness, percussion for shifting dullness, and auscultation for bowel sounds
-Digital rectal examination and pelvic examination in women
-Assessment of overall performance status and nutritional status.
Investigations:
-Serum tumor markers: CA-125, CEA, CA 19-9, AFP, PSA are important for monitoring and prognosis but are not diagnostic alone
-Imaging: CT scan of the abdomen and pelvis with intravenous contrast is the primary modality for staging and assessing the extent of PC, evaluating the PCI
-MRI may be used for specific indications
-PET-CT can assess metabolic activity and detect distant metastases
-Diagnostic laparoscopy is often performed to accurately assess the PCI and resectability
-Biopsy: Percutaneous biopsy or biopsy during laparoscopy for histological confirmation if diagnosis is uncertain.
Differential Diagnosis:
-Simple ascites of non-malignant origin (e.g., cirrhosis, heart failure)
-Benign peritoneal masses or cysts
-Other intra-abdominal malignancies without peritoneal spread
-Inflammatory conditions of the peritoneum (e.g., tuberculosis)
-Pseudomyxoma peritonei (often originating from mucinous tumors)
-Metastases to the omentum or peritoneum from non-abdominal primary sites.

Management

Indications For Crs Hipec:
-Peritoneal carcinomatosis confined to the peritoneum, with no evidence of distant extra-abdominal metastases
-Resectable primary tumor or recurrent tumor amenable to complete cytoreduction
-Adequate performance status (ECOG 0-2, KPS >70%) and physiological reserve to tolerate major surgery
-Patients with specific histologies like appendiceal, ovarian, gastric, colorectal, and peritoneal mesothelioma are often considered
-Absence of extensive liver or nodal involvement precluding complete cytoreduction.
Cytoreductive Surgery Crs:
-The goal of CRS is to achieve a Complete Cytoreduction (CC-0 or CC-1), meaning no visible tumor deposits greater than 0.5 cm remain in the peritoneal cavity
-This involves extensive surgical resection including peritonectomy procedures (e.g., omentectomy, splenectomy, partial or total gastrectomy, colectomy, cholecystectomy, hysterectomy, oophorectomy), lysis of adhesions, and meticulous removal of all tumor nodules from all peritoneal surfaces
-Operative findings are quantified using the Peritoneal Cancer Index (PCI), a numbering system from 0 to 39 based on the size and location of tumor implants across six abdominal regions.
Hyperthermic Intraperitoneal Chemotherapy Hipec:
-HIPEC involves perfusing the peritoneal cavity with heated chemotherapy agents (e.g., mitomycin C, oxaliplatin, cisplatin, doxorubicin) for a specific duration (typically 60-90 minutes) at a controlled temperature (40-43°C) after CRS
-The hyperthermia enhances drug penetration into tumor nodules and induces thermal cell kill, while the chemotherapy targets microscopic residual disease
-The choice of chemotherapy agent and dose depends on the primary tumor histology and established protocols
-Different HIPEC techniques exist, including open (coliseum) and closed abdomen methods.
Postoperative Care:
-Close monitoring in an intensive care unit (ICU) for hemodynamic stability, fluid balance, and organ function
-Aggressive pain management
-Nutritional support, often via total parenteral nutrition (TPN) initially, followed by gradual oral intake
-Management of potential complications like ileus, anastomotic leak, infection, electrolyte imbalances, and mucositis
-Early mobilization to prevent deep vein thrombosis and pulmonary complications
-Regular monitoring of tumor markers and clinical status.

Complications

Early Complications:
-Ileus: prolonged return of bowel function is common, often managed conservatively
-Anastomotic leak: risk is increased by extensive surgery and chemotherapy exposure
-Sepsis: intra-abdominal infection or systemic infection
-Hemorrhage: from operative sites or coagulopathy
-Renal insufficiency: due to nephrotoxic chemotherapy agents or dehydration
-Bone marrow suppression: neutropenia, thrombocytopenia from systemic absorption of chemotherapy
-Wound complications: infection, dehiscence.
Late Complications:
-Adhesions and bowel obstruction: long-term sequelae of extensive abdominal surgery
-Infertility: due to pelvic organ resection and chemotherapy
-Chronic pain: persistent abdominal discomfort
-Neodymium toxicity: associated with platinum-based agents
-Psychological distress: impact of cancer diagnosis and aggressive treatment
-Recurrence of peritoneal disease.
Prevention Strategies:
-Careful patient selection for CRS/HIPEC to minimize risk
-Meticulous surgical technique to reduce iatrogenic injury and ensure complete hemostasis
-Strict adherence to HIPEC protocols regarding drug dosage, temperature, and duration
-Prophylactic antibiotics and anticoagulation
-Aggressive postoperative fluid management and nutritional support
-Close monitoring for early detection and management of complications
-Thorough preoperative assessment of organ function.

Prognosis

Factors Affecting Prognosis:
-Completeness of cytoreduction (CC-0 vs
-CC-1 vs
-CC-2/3) is the most critical factor
-Peritoneal Cancer Index (PCI) at diagnosis and intraoperatively
-Histological type of the primary tumor (e.g., appendiceal mucinous adenocarcinoma generally has better prognosis)
-Patient's performance status and comorbidities
-Quality of HIPEC administration
-Presence and extent of residual tumor deposits
-Response to chemotherapy.
Outcomes:
-For selected patients with a complete cytoreduction (CC-0), the median survival can be significantly improved, often ranging from 20-50 months or longer, depending on the primary cancer
-Complete responders may achieve long-term disease-free survival
-For incomplete cytoreduction (CC-2/3), the prognosis remains poor
-HIPEC is generally considered beneficial as an adjunct to CRS for improving outcomes in specific cancer types.
Follow Up:
-Regular clinical assessment every 3-6 months for the first 2-3 years, then annually
-Serial imaging (CT scan) to monitor for recurrence
-Tumor marker monitoring (e.g., CA-125, CEA)
-Assessment of quality of life, nutritional status, and management of long-term sequelae
-Patients with complete remission may benefit from adjuvant systemic chemotherapy based on primary tumor type and risk stratification.

Key Points

Exam Focus:
-Understand the definition and rationale behind CRS and HIPEC
-Be able to identify indications and contraindications for the procedure
-Know the importance of PCI and CC scoring in surgical decision-making and prognosis
-Recognize the common primary tumors associated with PC and the typical chemotherapy agents used in HIPEC
-Recall key early and late complications.
Clinical Pearls:
-Always suspect peritoneal carcinomatosis in patients with intra-abdominal malignancy presenting with unexplained abdominal symptoms, especially ascites or obstruction
-The completeness of cytoreduction is paramount
-a CC-0 score dramatically alters prognosis
-HIPEC is an adjunct to surgery, not a standalone treatment for PC
-Patient selection is critical to maximize benefit and minimize morbidity.
Common Mistakes:
-Underestimating the extent of peritoneal disease on imaging, leading to inadequate surgical planning
-Failing to achieve complete cytoreduction due to inadequate surgical expertise or incorrect patient selection
-Administering HIPEC to patients with significant residual tumor or extra-abdominal disease
-Inadequate postoperative management, leading to preventable complications
-Not considering HIPEC for appropriate primary malignancies when PC is present.