Primary Peritoneal Cancer

• Primary Peritoneal Cancer is a rare cancer originating in the abdominal lining, distinct from cancers that have spread to the peritoneum.
• Its symptoms are often vague and can include abdominal pain, bloating, and changes in bowel habits.
• The exact causes are not fully understood, but risk factors are similar to those for ovarian cancer.
• Treatment typically involves a combination of surgery and chemotherapy.
• Early diagnosis is challenging due to non-specific symptoms, highlighting the importance of awareness.

What is Primary Peritoneal Cancer?

Primary Peritoneal Cancer refers to a rare type of cancer that begins in the peritoneum, the thin layer of tissue that lines the inside of the abdomen and covers organs such as the uterus, bladder, and rectum. Unlike metastatic cancer that spreads to the peritoneum from another site, primary peritoneal cancer originates directly in this tissue. It is histologically similar to epithelial ovarian cancer, often presenting with widespread disease throughout the abdominal cavity at diagnosis, even if the ovaries are unaffected or removed. According to the American Cancer Society, primary peritoneal cancer is much less common than ovarian cancer, but it behaves and is treated very similarly.

Symptoms and Causes of Primary Peritoneal Cancer

Recognizing primary peritoneal cancer symptoms can be challenging because they are often vague and non-specific, mimicking those of many other less serious conditions. These symptoms tend to develop gradually and may include:

• Abdominal bloating or distension
• Pelvic or abdominal pain
• Feeling full quickly when eating, or difficulty eating
• Changes in bowel habits, such as constipation or diarrhea
• Frequent urination
• Unexplained weight loss or gain
• Nausea or indigestion

The exact causes of primary peritoneal cancer are not fully understood. However, it is believed to arise from cells that are embryologically similar to those that give rise to ovarian cancer. Risk factors associated with primary peritoneal cancer largely overlap with those for ovarian cancer, including:

• Older age
• Genetic mutations, particularly in the BRCA1 and BRCA2 genes
• A family history of ovarian or breast cancer
• Endometriosis
• Obesity

It’s important to note that having one or more risk factors does not mean an individual will develop the cancer, and many people with the disease have no known risk factors.

Primary Peritoneal Cancer Treatment Options

Treatment for primary peritoneal cancer treatment typically involves a multi-modal approach, combining surgery with chemotherapy, similar to the management of advanced ovarian cancer. The primary goal of surgery is to remove as much of the visible tumor as possible, a procedure known as debulking or cytoreduction. This can significantly improve the effectiveness of subsequent chemotherapy.

Chemotherapy is usually administered after surgery (adjuvant chemotherapy) or sometimes before surgery (neoadjuvant chemotherapy) to shrink tumors and make them easier to remove. Common chemotherapy regimens involve platinum-based drugs (like carboplatin) and taxanes (like paclitaxel). In some cases, targeted therapies that focus on specific vulnerabilities in cancer cells, or immunotherapy, may be considered, especially for recurrent disease or specific genetic profiles. Clinical trials also offer access to new and experimental treatments that may be beneficial for some patients. The treatment plan is highly individualized, depending on the stage of the cancer, the patient’s overall health, and their response to therapy.