Why this treatment:

(1) Staging laparoscopy:

CT and PET scans cannot identify tumor nodules smaller than 5mm. Staging laparoscopy is a surgical procedure done under general anesthesia where an endoscope (camera) is inserted into the abdomen to visually inspect the disease spread. The spread of the disease is mapped and scored. We call it PCI: Peritoneal Carcinomatosis index. This score helps us decide which patient is suitable for major surgeries like Cytoreduction and HIPEC.

In the present case, the disease was too extensive, despite several rounds of chemotherapy. It appeared unlikely that she will ever come up for radical surgery. Staging laparoscopy helped us in mapping the disease now, so that we can monitor the response of PIPAC and IP chemotherapy that we were going to start.

(2) Peritoneal Biopsy:

Whenever we do laparoscopy for disease mapping, we routinely take biopsies from the peritoneum. Why is it necessary? Just because a tumor nodule is visible does not actually mean that there are viable cancer cells inside; when the patient has already received chemotherapy. Biopsy of such nodules will help us look for viable cancer cells and study the response of the tumour to treatment already given. Based on this information we can add to the treatment or change the treatment altogether. There is a possibility that the visible tumor nodules and plaques do not show any cancerous cells that are alive. In such cases these patients may be considered for a major surgery like Cytoreductive surgery and HIPEC.

In this patient the biopsy will provide fresh tissue sample to do genetic testing to understand what drugs may benefit her.

(3) Extensive peritoneal lavage:

The tumour deposits in the peritoneum constantly shed cancer cells into the peritoneal cavity. These free cancer cells get implanted in new sites and develop as new nodules. During laparoscopy we get an opportunity to wash the abdominal cavity to remove as many of these free floating cancer cells as possible. This is called peritoneal lavage. We use 10litres of normal saline to wash the abdomen cavity and suck it back. This aids in reducing the tumor burden and help in controlling the disease spread.

(4) PIPAC: Pressurized Intra Peritoneal Aerosolized Chemotherapy

Chemotherapy given through veins faces a barrier called bold peritoneal barrier. Hence it is not as effective on peritoneal deposits as it is on liver and lung metastasis. PIPAC is a procedure where the same chemotherapy particles are broken down into Nano particles and sprayed inside the abdomen. The pressure of the air used to inflate the abdomen in laparoscopy drives these nanoparticles inside the tumour nodules. The drugs directly attack the tumour cells and kill them.

In the present case the patient had received all the major drugs used for colon cancer and still the disease had progressed. Hence PIPAC was logical alternative in her case.

The dose of the chemotherapy drugs used in PIPAC is very small compared to IV chemotherapy. Hence this procedure does not produce significant side effects and patient can go home the next day.

(5) IP Port: Intra Peritoneal Port

PIPAC is a surgical procedure requiring hospital stay and anesthesia. This comes at an added cost. This treatment is not available in most of the centres. Hence patient may have to travel long distances for PIPAC. Intraperitoneal port serves as an add on procedure since it does not have the disadvantages of PIPAC.

Intraperitoneal port is a tube connected to a chamber. The tube is placed inside the abdomen while the chamber is fixed under the skin of the upper abdomen. Similar to Intravenous Chemoport , chemotherapy drugs can be instilled into the abdomen using this port.

In the present case, since the disease had progressed on IV chemotherapy we chose to insert IP port for this patient. Once the wounds heal, she will receive IP port chemotherapy which is combined with repeated PIPAC sessions.