Overview of peritoneal cancer
Peritoneal cancer is a rare cancer that occurs in a thin layer of epithelial cells that line the inner wall of the abdomen. This lining is called the peritoneum. The peritoneum protects and covers your abdominal organs, including:
The peritoneum also produces a lubricating fluid that allows organs to move easily within the abdomen.
Every case of peritoneal cancer is different. Treatment and perspective vary individually. New therapies developed over the past decades have improved survival rates.
Primary vs. secondary peritoneal cancer
The primary and secondary stages indicate where cancer started. Names are not a measure of the severity of cancer.
Primary peritoneal cancer begins and develops in the peritoneum. It usually affects only women and rarely affects men.
Primary peritoneal cancer is closely related to epithelial ovarian cancer. They both look the same and have a similar outlook.
Peritoneal malignant mesothelioma is a rare type of primary peritoneal cancer.
Secondary peritoneal cancer usually begins in another organ in the abdomen and spreads to the peritoneum (metastasizes).
Secondary peritoneal cancer can be started by:
- Fallopian tube
- Small intestine
Secondary peritoneal cancer affects both men and women. It is much more common than primary peritoneal cancer.
Doctors estimate that 15 to 20 per cent of people with colorectal cancer develop metastases to the peritoneum. About 10 to 15 per cent of people with stomach cancer develop metastases to the peritoneum.
When cancer metastasizes from its original site, the new site contains the same cancer cells as the initial site.
Symptoms of peritoneal cancer
The symptoms of peritoneal cancer depend on the type and stage of cancer. In its early stages, symptoms may not be present. Sometimes, there may be no symptoms even when peritoneal cancer develops.
Initial symptoms can be vague and can be due to several other conditions. Symptoms may include:
- Bloating or abdominal pain
- Dilated abdomen
- The sensation of pressure in the abdomen or pelvis.
- Integrity before finishing eating
- Nausea or vomiting
- Bowel or urinary changes
- Lack of appetite
- Weight loss or gain
- Vaginal discharge
- Back pain
As cancer progresses, fluid builds up in the abdominal cavity (ascites), causing:
- Nausea or vomiting
- Difficulty breathing
- Abdominal pain
Symptoms of end-stage of this cancer include:
- Complete bowel or urinary obstruction.
- Abdominal pain
- Inability to eat or drink
Stages of peritoneal cancer
When first diagnosed, it is shown by its size, location, and where it has spread. It is also assigned a rating that predicts how quickly it will spread.
Primary peritoneal cancer
Primary peritoneal cancer occurs with the same system that is used for ovarian cancer because the cancers are similar. It is always classified as stage 3 or stage 4. Ovarian cancer involves two previous stages.
Stage 3 is further divided into three stages:
- 3 A. Cancer has spread to lymph nodes outside of the peritoneum, or cancer cells have spread to the surface of the peritoneum outside of the pelvis.
- 3 B. Cancer has spread to the peritoneum outside of the pelvis. Peritoneal cancer is 2 cm (cm) or smaller. It can also spread to lymph nodes outside the peritoneum.
- 3 c. Cancer spreads to the peritoneum outside of the pelvis and. It is larger than 2 cm. It can spread to lymph nodes outside the peritoneum or to the surface of the liver or spleen.
In stage 4, cancer spreads to other organs. This step is subdivided into:
- 4 A. Cancer cells are found in the fluid that collects around the lungs.
- 4 B. Cancer has spread to organs and tissues outside the abdomen, such as the liver, lungs, or lymph nodes in the groin.
Secondary peritoneal cancer
It occurs based on the site of primary cancer. When primary cancer spreads to another part of the body, such as the peritoneum, it is usually classified as stage 4 of the original cancer.
Peritoneal cancer causes and risk factors
The cause is unknown.
For primary peritoneal cancer, risk factors include:
- Age. Your risk increases as you get older.
- Genetics. Family history can increase your risk. Taking a gene for the BRCA1 or BRCA2 mutation or Lynch syndrome also increases your risk.
- Hormone therapy. Taking hormone therapy after menopause may slightly increase your risk.
- Weight and height. Being overweight or having one increases your risk. The risk is higher for those who are taller.
- Endometriosis Increases your risk of endometriosis.
Factors that reduce the risk of ovarian cancer:
- Taking birth control pills
- Have children
- Tubal ligation, fallopian tube removal, or ovarian removal.
Keep in mind that ovarian removal reduces the risk, but does not eliminate it.
How peritoneal cancer is diagnosed
Diagnosis of primary and secondary peritoneal cancer is difficult at an early stage.
It often appears only during surgery to remove a known tumour in another part of the abdomen.
Your doctor will physically examine you, take a medical history, and ask about your symptoms. They may order a series of tests to determine the diagnosis.
Tests used to diagnose:
- Imaging exams of the abdomen and pelvis. It can show ups and downs. Tests include CT, ultrasound, and MRI. However, it is difficult to diagnose using CT scans and MRIs.
- For cancer cells, a biopsy of the abnormally visible area on the scan, removing fluid from the ascites. Discuss both with your doctor. This procedure is also dangerous if the abdominal wall is infested with cancer cells.
- Blood tests to look for chemicals that grow in peritoneal cancer, such as CA 125, a chemical made by tumour cells. The new blood marker is HE4. It is lower than CA 125 to increase in cancer-free conditions.
- Laparoscopy or laparotomy.These are minimally invasive methods to look directly at the peritoneum. They are considered the “gold standard” in diagnosis. Research on improved and older methods to diagnose peritoneal cancer is ongoing.
Treating peritoneal cancer
You have a treatment team that includes:
- A surgeon
- A pathologist
- Pain specialist
- Specialized nurses
- Palliative care professionals
The treatment of primary peritoneal cancer is similar to that of ovarian cancer. For primary and secondary cancer, individual treatment depends on the location and size of the tumour and your general health.
Treatment of secondary peritoneal cancer also depends on the condition of primary cancer and its response to treatment.
Surgery is usually the first step. A surgeon removes as much cancer as possible. They can also be removed:
- Your uterus (cervical surgery)
- Your ovaries and fallopian tubes (oophorectomy)
- A layer of fatty tissue near the ovaries (omentum)
Your surgeon will also remove any abnormally visible tissue in the abdominal area for a more detailed examination.
Advances in the precision of surgical procedures known as cytoreductive surgery (CRS) have allowed surgeons to remove most of the cancerous tissue.
What’s the outlook?
The prognosis for people with primary or secondary peritoneal cancer has improved significantly in recent decades due to advances in treatment, but it is still poor. It is usually not diagnosed until it is in an advanced stage. Also, cancer can come back after treatment.
Symptoms can be difficult to diagnose, but if you have some common symptoms, see your doctor. A previous diagnosis can lead to a better result.