What is the diagnosis and treatment for peritoneal carcinomatosis (cancer spread to the peritoneum)?

From the Guidelines

Peritoneal carcinomatosis should be treated with cytoreductive surgery (CRS) alone in selected patients, as the addition of hyperthermic intraperitoneal chemotherapy (HIPEC) has not shown a therapeutic benefit and is associated with excessive toxicity, as evidenced by a randomized study in patients with colon cancer and peritoneal carcinomatosis 1.

Diagnosis and Treatment Approach

The diagnosis of peritoneal carcinomatosis involves identifying cancer cells in the peritoneal cavity, often through imaging studies or surgical exploration. Treatment approaches vary based on the primary cancer type, extent of disease, and patient performance status.

• Systemic chemotherapy is a mainstay of treatment, with regimens tailored to the primary cancer type, such as FOLFOX or FOLFIRI for colorectal cancer, or platinum-based regimens for ovarian cancer.
• Cytoreductive surgery (CRS) may be considered for selected patients with limited disease extent and good performance status, with the goal of removing all visible tumor nodules.
• The role of HIPEC in the treatment of peritoneal carcinomatosis is still being debated, but recent evidence suggests that it may not provide additional benefit over CRS alone, particularly in patients with colon cancer and peritoneal carcinomatosis 1.

Patient Selection for CRS

Patient selection for CRS is critical, and candidates should be carefully evaluated based on factors such as:

• Good performance status
• Limited burden of peritoneal involvement, as assessed by the peritoneal cancer index (PCI)
• Absence of extraperitoneal metastases
• Potential for complete cytoreduction

Symptom Management

Symptom management is an essential component of care for patients with peritoneal carcinomatosis, including treatment for:

• Ascites (fluid buildup)
• Bowel obstruction
• Pain These symptoms can significantly impact quality of life, and effective management is crucial to improving patient outcomes.

Evidence-Based Recommendations

The most recent and highest quality study on this topic, published in 2023, provides guidance on the diagnosis and treatment of peritoneal carcinomatosis, including the role of CRS and HIPEC 1. This study highlights the importance of careful patient selection and the potential benefits of CRS alone in selected patients.

From the FDA Drug Label

1.6 Epithelial Ovarian, Fallopian Tube, or Primary Peritoneal Cancer Avzivi, in combination with paclitaxel, pegylated liposomal doxorubicin, or topotecan, is indicated for the treatment of patients with platinum-resistant recurrent epithelial ovarian, fallopian tube or primary peritoneal cancer who received no more than 2 prior chemotherapy regimens.

The diagnosis of peritoneal carcinomatosis is not directly addressed in the label. The treatment for peritoneal carcinomatosis (specifically primary peritoneal cancer) is bevacizumab (Avzivi) in combination with paclitaxel, pegylated liposomal doxorubicin, or topotecan for patients with platinum-resistant recurrent disease who have received no more than 2 prior chemotherapy regimens 2.

From the Research

Diagnosis of Peritoneal Carcinomatosis

• Peritoneal carcinomatosis is an advanced stage of tumor dissemination of abdominal cancers, particularly colorectal cancer 3.
• Diagnosis is typically made through evaluation of evidence-based medical literature and current guidelines 3.

Treatment of Peritoneal Carcinomatosis

• The treatment of choice for peritoneal carcinomatosis of colorectal, ovarian, and mucinous appendicular origin is cytoreductive surgery (CR) with hyperthermic intraperitoneal chemotherapy (HIPEC) 3, 4, 5, 6, 7.
• Cytoreductive surgery involves the removal of all visible tumor tissue, and HIPEC involves the administration of heated chemotherapy directly into the abdominal cavity 4, 6, 7.
• Proper patient selection is mandatory, and quantitative prognostic indicators such as tumor histopathology, classification of carcinomatosis extent, and assessment of completeness of cytoreduction are used to determine eligibility for treatment 6, 7.
• The treatment approach has been shown to be effective in carefully selected patients, offering a chance for cure or palliation in a condition with few alternative treatment options 6.
• The treatment can result in significant survival benefits, with mean increases in survival period ranging from six months to up to four years 7.

Complications and Outcomes

• The incidence of significant postoperative complications can be as high as 15% 3.
• Minor complications such as pleural effusion, leukopenia, fever, and prolonged paralytic ileus can occur, but major complications are rare 4.
• Perioperative mortality is low, and some patients have survived more than 5 years after treatment 4.
• The treatment approach requires a standardized perioperative management and patient selection to optimize results 3.