Scientists have discovered that the presence of a benign nail deformity may lead to the diagnosis of a rare genetic disorder that increases the risk of developing cancerous tumors in the skin, eyes, kidneys and tissues that line the chest and abdomen.
This condition, known as “BAP1 tumor predisposition syndrome,” is caused by mutations in the BAP1 gene, which normally acts as a tumor suppressor, among other functions.
The scientists made this discovery while studying participants who were enrolled in screening for BAP 1 variants at the National Institutes of Health (NIH) Clinical Center.
As part of the study, dermatological examination was performed at enrollment and annually.
The group participating in the current study included 47 individuals with “BAP1 tumor predisposition syndrome” from 35 families.
“When asked about nail health during a baseline genetic evaluation, one very intelligent patient reported that he noticed subtle changes in his nails,” said co-lead author and genetic counselor Alexandra Leibenson, of the National Cancer Institute (NCI) of the National Institutes of Health. “His comment prompted us to conduct an evaluation.” "A systematic approach to other participants' nail changes and revealed this new finding."
In several participants, a nail biopsy and core nail biopsy confirmed researchers' suspicions of an abnormal benign tumor known as an onychopapilloma.
This condition causes a colored band (usually white or red) to appear along the length of the nail, in addition to thickening of the nail below the discolouration and thickening of the end of the nail. It usually affects only one finger.
However, among study participants with “BAP1 tumor predisposition syndrome” who were aged 30 years and older, 88% had onychomatous papillomas affecting multiple nails.
The researchers suggest that nail examination may be particularly valuable in a patient with a personal or family history of skin cancer or other potential malignancy associated with BAP1.
“This finding is rarely observed in the general population, and we believe that the presence of nail changes indicates The presence of nail papillomas on multiple nails should prompt consideration of the diagnosis of BAP1 tumor predisposition syndrome.”
The findings were published in JAMA Dermatology and presented at the Society for Investigative Dermatology (SID 2024) annual meeting held in Dallas May 15-18.