New-Age Chemotherapy Treatments
Chemotherapy is typically known as treatments for cancer patients that involve strong doses of medication administered intravenously and are targeted at destroying cancerous cells in the body.
The evolving world of medical technology has given cancer patients more treatment options with the possibility of better treatment outcomes.
Consultant General and Colorectal Surgery at Makhota Medical Centre, Dr. Ang Chin Wee shares about Heated Intraperitoneal chemotherapy (HIPEC) and Pressurised Intraperitoneal Aerosol Chemotherapy (PIPAC) or also known as Hot Chemotherapy and Spraying Chemotherapy subsequently, which are newer methods of cancer treatment.
1Twenty80: Could you explain what hot chemotherapy and spraying chemotherapy are?
Dr. Ang Chin Wee: Hot chemotherapy is medically termed Heated Intraperitoneal chemotherapy (HIPEC). It is used in patients with advanced abdominal and pelvic cancers that have spread specifically to the inner lining of the abdomen, called the peritoneum (peritoneal cancer).
Spraying chemotherapy, on the other hand, is medically termed Pressurised Intraperitoneal Aerosol Chemotherapy (PIPAC). This treatment is also specifically for peritoneal cancers and can be considered for patients who are not suitable for HIPEC.
These two types of treatments deliver chemotherapy directly into the abdominal cavity and to the cancer cells in the peritoneum.
These two types of treatments deliver chemotherapy directly into the abdominal cavity and to the cancer cells in the peritoneum.
1Twenty80: How are these treatment options different from conventional chemotherapy?
Dr. Ang: Both HIPEC and PIPAC are specifically indicated for peritoneal cancers. Peritoneal cancers are a particular group of cancers usually spread from other primary cancer sites, including colorectal cancer, gastric cancer, and ovarian cancer. Therefore, HIPEC treatment is for Stage 4 cancers that have spread to the peritoneum. However, there are other cancers that originate primarily from the peritoneum, which would also be suitable for HIPEC/PIPAC.
Conventional chemotherapy is administered by injecting the chemotherapy into the vein and circulating in the bloodstream. This method of chemotherapy delivery is known to have poor efficacy to cancers in the peritoneum because the drug does not penetrate the peritoneum well from the circulating blood system to reach the tumour. On the other hand, both HIPEC and PIPAC involve the delivery of chemotherapy directly to the tumour by infusing the drug into the abdominal cavity and therefore, increasing the drug contact and penetration into the tumour.
1Twenty80: As for the side effects of the treatments, is there a difference as compared to conventional chemotherapy?
Dr. Ang: Given that the mode of the chemotherapy drug delivery is different, the safety/adverse effect profiles between HIPEC/ PIPAC and conventional chemotherapy are different. HIPEC and PIPAC are surgeries and thus, surgical risks would be taken into consideration. With regards to adverse effects related to chemotherapy itself, conventional chemotherapy would have numerous systemic side effects such as nausea, hair loss, fatigue, loss of appetite, and infection, whereas the absorption of chemotherapy from HIPEC/PIPAC in the abdominal cavity into the systemic circulation is very low and therefore causing minimal systemic adverse effects.
1Twenty80: Who makes a suitable candidate for these new treatment options?
Dr. Ang: First of all, for HIPEC/PIPAC, patients must have cancers that have spread to the peritoneum. Cancer types suitable for these treatments would be those that are usually known to respond to conventional chemotherapy.
For HIPEC, it is essentially part of the major operation where it is aimed for cure and surgeons would remove most if not all the cancers visible inside the abdomen. Therefore, patients would need to be reasonably fit to undergo such major surgery. For aggressive cancers that are too extensive in the abdominal cavity and peritoneum, HIPEC may not be suitable if surgeons are unable to remove most of the tumours. In this instance, PIPAC would then be considered. Currently, PIPAC is considered as a palliative treatment (such as not aiming for cure as in HIPEC), which helps to control peritoneal disease and hence, reduces symptoms due to abdominal fluid accumulation, pain or impending bowel obstruction. In rare circumstances, PIPAC has also been used as a strategy to shrink the tumour first before performing HIPEC later.
1Twenty80: Could you give us a glimpse of what goes on during these treatment options?
Dr. Ang: For HIPEC, in this treatment, warmed anti-cancer chemotherapy will be infused and circulated in the abdominal cavity for 30 to 90 minutes, depending on the cancer type.
Firstly, surgeons will ensure the right indication for the HIPEC procedure. This would involve staging of the cancer with Computed Tomography (CT) and Positron Emission Tomography (PET) scans. Occasionally, a key-hole surgery called laparoscopy is performed to assess and visualize the extent of the peritoneal disease and if the patient would benefit from HIPEC treatment.
On the day of the HIPEC procedure, the patient would undergo general anaesthesia. Surgeons will firstly remove most if not all the visible tumours in the abdominal cavity and the peritoneum (also named cytoreductive surgery, CRS). Then, specific chemotherapy targeted for the cancer types would be heated by a special machine to approximately 41 to 42°C before infusing and circulating into the abdomen continuously for 30 to 90 minutes. Once HIPEC treatment is completed, the surgeon will finally close the abdomen and surgery is completed.
On the other hand, PIPAC is performed via a minimally invasive surgical procedure called laparoscopy and hence, less invasive. During laparoscopy, the patient would undergo general anaesthesia. The surgeon would make several very small incisions and insert key-hole ports into the abdomen, and carbon dioxide gas would be used to distend the abdominal cavity like a balloon so that a small camera can be inserted via the port to visualise and assess the peritoneal tumours and abdominal contents. Then, specific chemotherapy targeted for the cancer types would be made into gas form by a special machine before infusing and circulating into the abdomen continuously for 30 minutes. The surgeon does not remove tumours in this procedure. Once PIPAC treatment is completed, the surgeon will close the abdomen and surgery is completed.
The success of hipec treatment is largely dependent on the aggressiveness, the extensiveness, and the origin of the cancer in the abdomen.
1Twenty80: Lastly, could you share with us some information about this treatment option implemented in other countries and its success rates?
Dr. Ang: HIPEC and PIPAC treatments are fairly new and uncommon in Malaysia, although HIPEC was invented in the 1980s and has been in clinical practice for over 20 years in many countries, such as the UK, France, Spain, US, Taiwan, Australia, Singapore and so on.
The success of HIPEC treatment is largely dependent on the aggressiveness, the extensiveness, and the origin of the cancer in the abdomen. Some cancers such as the cancer of the appendix respond very well to HIPEC treatment and have a high success rate. The key to the success of HIPEC is early diagnosis of the peritoneal spread of abdominal and pelvic cancers, early referral to the specialised centre and treatment instituted by experienced surgeons and oncologists.
PIPAC was invented in the early 2010s. It is considered an effective palliative treatment to improve the patient’s symptoms due to excessive abdominal fluid accumulation, pain or impending bowel obstruction. Therefore, PIPAC may not prolong survival from cancer but would help to improve a patient’s quality of life. Lately, PIPAC has also been used as a strategy to shrink the tumour first before performing HIPEC later.