IceSense uses extreme cold to kill off diseased tissue in a non-invasive procedure that does not leave scarsA new development that will one day enable the removal of breast lumps and tumors with a device that is no more invasive than a needle prick is very cool. Literally.

Israel’s Arbel Medical hopes that its IceSense technology will pave the way for simple cryotherapy, a method of surgery that uses extreme cold to kill diseased tissue.

There are 15 million women in the United States suffering from benign breast lumps. Every year one million women are sliced open on the operating table in expensive surgery to remove breast lumps.

“Half the medical world is dealing with removing these [lumps],” says Didier Toubia, CEO of the Yokneam-based company. “At present there are no non-invasive treatments for benign breast lumps.”

According to Dr Rafi Klein, a senior surgeon specializing in breast surgery at the Ramban Medical Center in Haifa and an advisor for Arbel, the threat of cancer prompts doctors to recommend removing all breast lumps even from young women.

“There is a lot of demand for finding a solution to surgery without causing scars,” he told ISRAEL21c.

IceSense provides that solution by offering the hope of efficient treatment in local clinics without the need for hospitalization, recuperation, or scarring. The IceSense mechanism enables the local application of super-cold temperatures and a fine control of the temperature itself. Liquid nitrogen is pumped to the end of a thin needle probe cooling the tip to the extreme cold required for cryotherapy. Utilizing ultrasound, surgeons can then guide the needle to the exact location of the lump and then freeze the unwanted tissue inside the body.

About the same size as a washing machine, the IceSense apparatus can be operated even in local clinics and medical centers. Providing treatment for breast lumps in local medical centers would be a big step towards the current trend in the US to conduct as much surgery as possible in local clinics by using non-invasive methods. This keeps expensive and over-worked operating rooms and teams free for more serious surgical procedures that require a hospital environment.

An hour-long surgery to remove a breast lump requires a full operating room team, costs about $2,000 and takes up several hours of the patient’s time with pre and post operation procedures. And the scars left behind will last a lifetime. An IceSense treatment will cost less than half that amount, take less than an hour at the clinic, and patients will be able to walk out right after the procedure.

While the theory of cryotreatment has been around for over 30 years, practical restraints have prevented its use for internal medicine. Although widely used today to treat external skin problems such as warts, moles, and cysts, using the same method for internal disorders is problematic. Effective treatment demands temperatures well below freezing point and generating such low temperatures in a way that is also convenient for the tightly controlled environment of invasive surgery is fraught with difficulties.

The most popular method of achieving cryotemperatures, that is temperatures well below freezing point, is by using liquid nitrogen. Nitrogen, the gas that makes up nearly 80% of the air that we breathe, is still viscous at 170 degrees centigrade below zero. This super-cold liquid is used in a variety of applications to provide extreme cooling. However, applying liquid nitrogen to internal tissue without using invasive surgery to cut a clear path to the target is impractical. The storage and handling of liquid nitrogen is awkward, requiring cumbersome vacuum-insulated storage vats and expensive piping to deliver the liquid before it boils into a gas. In addition, most liquid nitrogen systems are designed to supply the liquid at high pressure that is at odds with the delicacy of surgery.

Arbel engineer Alexander Levin explains that building a system to work with surgically small and precise amounts of liquid nitrogen was a challenge. Just keeping the nitrogen as a liquid while it is transferred to the probe required a newly designed siphon, but the real problem was concentrating the nitrogen in the end of the probe without freezing the entire length of the shaft. If the temperature of the shaft became super-cold it would freeze healthy tissue along its length.

“We needed to overcome all of these problems,” Levin recalls.

Levin resolved the difficulties by pulsing the nitrogen instead of using a steady flow. The pulses of just 0.2 grams of nitrogen do not cool the shaft of the probe but when collected in the tip the liquid boils into gas drawing heat from the end of the probe and the surrounding body tissue. The gaseous nitrogen is then drawn off back down the probe. As the temperature at the end of the probe plummets, an ice-ball forms around the tip freezing the surrounding body tissue.

The pulse mechanism enables precise and subtle temperature control at the tip of the probe ensuring the resulting ice-ball freezes only the target tissue. The IceSense pulse system gives surgeons precise control over the size and application of the ice-ball to minimize any collateral damage and target only the intended tissue.

The freezing procedure has several advantages over invasive knife surgery. It is easier to perform and does not require an operating room and team. In addition, the extreme cold acts as a form of anesthetic numbing the patient’s sensations in the area around the probe and reducing the need for chemical anesthetics.

Recuperation from cryosurgery is also healthier for the patient. The sudden surgical plundering of diseased tissue is traumatic for the body, but with cryotherapy the frozen tissue remains in place and is then dissolved out of the body by the immune system.

This natural method of disposal has an added bonus; regular knife surgery to remove cancerous tissue is always likely to leave behind some cancerous cells that escape the surgeon’s efforts. The remaining cells can spawn a return of the cancer in the same location. However, the dead tissue left behind after cryosurgery triggers a vigorous immune reaction. This heightened immune response has proved effective in killing off lingering cancerous tissue and may safe-guard against a resurgence of the disease.

According to Klein the procedure is similar to a needle biopsy. Although at first only a qualified general surgeon will be authorized to use IceSense, Klein predicts the procedure may follow the course of needle biopsies that were at first performed only by surgeons, but today are conducted by x-ray technicians as well. Once a surgeon has approved the procedure, an x-ray technician would be authorized to remove the lump.

Klein says that the benefits to the patient of non-invasive surgery outweigh the disadvantages to surgeons who tend to prefer a more tactile approach to surgery.

“Surgeons are like children – they like to feel things in their hands,” he says. “At first if feels like you are missing something but we are doctors and if you can do something that the patient feels better with and leaves no scars you feel better about it because it is better for the patient.”

At present Arbel intends to focus on benign breast lumps before expanding the technology for use to treat breast cancer as well. Benign lumps are easier to treat and the paperwork required to perform the procedures is easier. Toubia will begin trials on patients at the end of the year in Israel and intends to apply for FDA clearance to start clinical trials in the US by spring next year.

“It is an attractive business venture,” says Toubia who hopes to capture some 40% of the $500 million breast-lump market after IceSense becomes available to the public in 2009.

Toubia envisions breast cancer clinics using IceSense to treat women in a simple and quick procedure that only requires a local anesthetic. If successful IceSense will increase the number of women that can be treated on a daily basis as well as alleviate the difficult dilemma that many young women face when diagnosed with a breast lump.

“The whole decision as to whether or not to take out a lump will be made much easier,” Klein says. “Today women have to consider if they want to have surgery whereas like this it is much easier to do and more young women will choose to do it.”



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