“Clearly we were faced with a situation that required a little more thought, and perhaps even to use different and complementary approaches,” pediatric surgeon Nelson Piché explained to The Canadian Press.
The child, who we will call Remi, had been diagnosed with sarcoma, a form of cancer that starts in the soft tissues of the body. He had already been operated on three times to remove the cancer that was invading his abdomen.
When the disease returned in force, Doctor Piché and his colleagues decided to turn to heated chemotherapy. While it is increasingly popular, the technique had apparently never been used before in such a young patient in Canada.
During the surgery on June 18, which lasted four hours, the doctors first removed all the cancer they saw; the problem, and this is what seems to have happened with Rémi, is that it is seldom possible to be sure that you have removed all of the cancer, and that the disease will not be back in a few months .
Heated chemotherapy then comes into play.
“It’s as if this chemo penetrates into all the little cells on the surface of everything in the belly so that, if there are cancer cells, they can be eliminated by chemotherapy. », Explained Doctor Piché.
After being heated to around 41 degrees Celsius, the chemotherapy, instead of being injected into the veins as in normal treatment, circulates for an hour on the surface of all the organs of the abdominal cavity which “could be the seat of one or a small colony of cancerous cells that risk metastasizing again in the future, ”he added.
Chemotherapy enters the abdomen through two tubes and exits through two more, ensuring that it is always properly heated and passes over all surfaces of the organs.
Because it is heated, the liquid penetrates to a depth of 2 to 2.5 mm in the tissues, instead of only 1 or 1.5 mm. A difference of as little as a millimeter may seem small, but it is of utmost importance when it comes to joining and destroying as many cancer cells as possible.
“The advantage of putting chemotherapy in the stomach, and not in the veins, is that it goes directly to where you think the risk of recurrence is the highest,” said Dr. Piché. We hope that by having treated locally, with very high concentrations of chemotherapy heated in his belly, that we can reduce the risk of recurrence. “
The technique makes it possible to use doses of chemotherapy that are incredibly more potent than what would otherwise be injected. It also helps to avoid – or at least decrease the intensity of – most of the well-known unwanted side effects associated with chemotherapy.
The mechanism that makes heated chemotherapy effective is not well understood, but Dr. Piché offers an interesting analogy.
“When you want to increase the permeability of the skin, when you want to open the pores of the skin, you put on hot compresses and that allows you to penetrate a little more,” he said. I would tell you that it is somewhat the same principle. “
Heated chemotherapy, while still new, is increasingly used in Canada, the United States and elsewhere. In Montreal, Dr. Pierre Dubé, of Hôpital Maisonneuve-Rosemont, uses it regularly and is a pioneer in the field; It is in particular under his tutelage that Doctor Piché studied.
During Rémi’s intervention, Doctor Piché used equipment loaned by Maisonneuve-Rosemont and he was able to count on the collaboration of an American surgeon who is probably the most experienced on the planet in this field.
It was still necessary to wait for a perfect alignment of the stars before operating a first child.
“We’ve been ready for seven years, but it was the first time that a patient met all the criteria: a tumor for which we know that there is chemotherapy that we can heat and that we know which is effective (…) and the tumor must not have gone elsewhere in the body, ”explained Dr. Piché.
Although cancer is the second leading cause of pediatric death after trauma, pediatric tumors are (fortunately) rare. For example, there are approximately 750 cases of neuroblastoma each year in the United States, a cancer that begins in immature nerve cells of the sympathetic nervous system, but more than 100,000 cases of colon or breast cancer.
The opportunities to use heated chemotherapy in pediatrics are therefore less frequent, especially since the technique is not appropriate for all types of cancer and can only be used for an “even less common tumor sub-category. », Underlined Doctor Piché.
In fine fettle
Rémi is currently in great shape and is recovering very well from his operation.
He still has a long way to go. He will continue to be treated in oncology at Sainte-Justine, both with conventional chemotherapy and with a therapy tailored to him, and he will undergo several tests to ensure that the cancer does not surreptitiously try to re-establish itself. We also set up a research protocol in which he is the only participant.
If ever this should be necessary, a new operation with heated chemotherapy will be possible, assures Doctor Piché.
“To have done so, it is certain that it will facilitate the use of this technique for other patients for the future,” he said. We still have to choose our patients very selectively. Just because we are capable of doing it does not mean that we have to do it all over the place. ”
But while probably few children, in absolute numbers, will benefit from this approach in the years to come, he stressed in a subsequent email, “What is important is that we now have the capacity to do so. ‘offer an innovative treatment that has proven its effectiveness in adults for those children who face a situation for which current methods have failed (or are at risk of failure) ”.
“In other words, even if the number is small, the value is immense for those who can benefit from it,” wrote Dr. Piché.