RNA sampling via tape strips may rule out melanoma in suspicious lesions

Key takeaways:

• RNA derived tape stripping proved to have a 100% sensitivity for identifying cutaneous malignant melanoma.
• This method reduced unnecessary excision by 32%.

Obtaining RNA samples from suspicious lesions via tape stripping was found to be a valid technique for detecting cutaneous malignant melanoma, according to a study.

“Distinguishing cutaneous malignant melanoma (CMM) from nevi can be a clinical challenge,” Ida M. Heerfordt, MD, PhD, of the department of dermatology at Copenhagen University Hospital in Denmark, and colleagues wrote.

In fact, between practitioners with dermoscopy experience and primary care physicians, eight to more than 20 benign lesions are removed to find a single CMM, the researchers continued.

“A noninvasive test to improve the clinical accuracy of CMM detection using RNA profiles obtained by tape strips from the lesion surface has been proposed,” Heerfordt and colleagues wrote, adding that the sensitivity of these tests has raised concerns about the risk of overlooking CMM in suspicious lesions.

In this study, the authors evaluated the validity and sensitivity of tape strip derived RNA profiles to rule out CMM in clinically suspicious lesions. They assessed 200 lesions using the CMM tape strips followed by an investigation of the expression levels of 11 genes using RNA measurement. A total of 73 CMMs and 127 non-CMMs were included.

Results showed that tape strip derived RNA testing was able to identify all CMMs demonstrating 100% sensitivity. These findings were due to the elevated expression levels of two oncogenes, PRAME and KIT, compared with housekeeping gene RPL18.

The technique also correctly excluded CMM in 32% of non-CMM lesions, demonstrating a 32% specificity. This indicates that RNA sampled by tape stripping can reduce the number of lesions removed unnecessarily by nearly one-third without missing CMMs, according to the researchers.

The researchers also noted that for this testing method to be effective, storage time must be kept shorter than 14 days, as any longer may cause the RNA to break down.

“RNA sampled by tape stripping is a useful noninvasive method to distinguish CMM from other lesions,” Heerfordt and colleagues concluded.