Sticking It to Cancer: Adhesive Patch Skin Biopsy Kit for Detecting Melanoma

testing-for-melanomaIt only takes three words to send life into a tailspin: “I have cancer.” Whether it’s you or someone you know, life will never be the same after hearing those words. Even if treatment is successful, there’s always a difference between “before cancer” life and “after cancer” life.

Scientists are working hard to create new treatments for cancer patients, as well as advance early detection strategies to increase survival rates. Melanoma, in particular, is a case where early detection is critical. While not the most common form of skin cancer, it is the most deadly. If allowed to metastasize, melanoma becomes incredibly difficult to treat.

Detecting melanoma used to require biopsies. The suspicious mole or growth would need to be physically cut from the body in order to test it. This method is imperfect. First, any sort of surgical procedure risks infection, and older people, who are also more prone to lesions given their age and increased sun exposure, are at a greater risk of infection than the general population. Second, because invasive procedures are uncomfortable and require follow-up appointments, dermatologists and patients alike only want to remove lesions they feel they must. This means melanoma is first suspected and biopsied based on visual cues that can be misinterpreted. Benign lesions may be cut unnecessarily, and malignant lesions may be missed. And because invasive procedures are a multi-step process, diagnoses will be delayed. Third, no one wants to go under the knife. Fear of invasive procedures has, in the past, prevented people from seeking dermatological help until it was too late.

DermTech has found a solution to prevent patients from undergoing unnecessary invasive procedures and to encourage early detection. Their team has developed a non-invasive adhesive patch biopsy that uses molecular analyses of skin cells to test for two key genes associated with melanoma. Adhesive circles are placed onto the lesion–4 adhesive circles are placed consecutively onto the lesion. When removed, the adhesive removes part of the stratum corneum: the outermost layer of skin. Sound scary? For context, when you exfoliate you remove the top layers of the stratum corneum as well. It’s no more painful than taking off a band-aid. While such a small test may seem ineffective, remember that this is a molecular test. Labs are looking for genes in the RNA of the cells, which means the skin cells picked up on the adhesive are sufficient to make a reliable diagnosis.

Early detection can be life-saving for some cancer patients. That’s why this new adhesive is revolutionary. Dr. Laura Korb Ferris, a professor of dermatology at the University of Pittsburgh, explained that dermatologists using these assays in their decision-making processes “surgically biopsy about half as often and miss fewer melanomas” than those who do not. It also means they can check more lesions. Instead of needing to pick and choose which of multiple suspicious spots seem most unusual (which can lead to not biopsying the malignant lesions,) they can test multiple spots in one visit. Especially if you have family history of melanoma, are fair-skinned, or live in a sunny area, being able to identify which spots are a problem without continually undergoing painful procedures is incredible.

How does this relate to PSI? The adhesives used in DermTech’s product include a rubber-based non-polar polymer adhesive. Rubber-based adhesives have “high peel, high shear, and high tack,” and are more hydrophobic, and softer than other adhesives. They are also “inert to biomolecules and to chemicals used to isolate biomolecules, especially nucleic acids.” In short, they pick up more cells, won’t be disrupted by water, and will not react to the chemicals needed to test the genes. And because the rubber adhesive can be applied to a film, the tape is pliable: able to mold to a lesion of any size or shape. Polymers make this technology possible.

Having technology that makes identification of skin cancer faster, easier, and more comfortable will lead to more early detection cases. Countless lives will be saved in the process, proving that polymers are so much more than just giant molecules.