A mutation of the BAP1 gene is implicated in the development of cancers like melanoma and mesothelioma. Screening for characteristic skin lesions can help in the early detection of tumors associated with BAP1 cancer syndrome.
Our best defence against cancer is early detection. This has been shown in many instances to improve response rates and leads to better treatment outcomes. But malignancies also develop in areas that are easily missed in routine examinations. Skin cancers like melanomas may be relatively detectable, but some patients actually develop them in hard-to-spot areas, like the uvea of the eye, and this is not usually screened for. This makes diagnosis difficult and often too late for any intervention.
Research has determined that a genetic mutation may be responsible for the development of these melanomas in the eye. Many patients suffering from this form of cancer have demonstrated mutations in the BAP1 gene. Not only is there a direct correlation between the BAP1 gene and melanoma, there is also evidence that the BAP1 mutation is present in patients with mesothelioma (cancer that affects the lining of the chest cavity) or kidney cancer. The potential to develop these malignancies as a result of the identified mutation is designated as BAP1 Syndrome and because of its genetic character, the possibility of developing these malignancies can be passed down to the next generation.
Those who have this gene mutation may also present with skin lesions called melanocytic BAPI-mutated atypical intradermal tumors (MBAITs). With their characteristic dome shape, these pigmented spots can be seen throughout the body of some patients. Could these lesions serve as early warning signs for cancer development?
This probable link was investigated by dermatologists from the Massachusetts General Hospital, with their findings published in the August 2017 edition of JAMA Dermatology. The investigators set out by identifying patients with confirmed family histories of these specific cancers. DNA samples were obtained to ascertain if they indeed had the BAP1 mutation. The dermatologists also conducted total body skin examinations (TBSEs), and any skin lesions closely resembling MBAITs were subsequently biopsied.
Of the 215 patients enrolled in the study, over 75% of them were seen to have MBAITs, which were confirmed by biopsy. These findings were then correlated with the DNA profiles as well as the family and medical histories. The results indeed confirm that a link exists between MBAITs and malignancies among these populations and that the presence of these lesions can serve as a precursor to possibly developing related cancers.
Establishing this correlation is crucial in early detection, as patients with relevant family histories can now undergo specific screening procedures. In the future, dermatologists who identify MBAITs in patients with this genetic profile can send them sooner to specialists who can specifically screen for possible lesions, whether in the eye, the chest cavity, or the kidneys.
For those living with this BAP1 syndrome mutation, measures of early identification and detection indeed offer hope—and while it is no guarantee of cure, perhaps it can alleviate some of the dread and anguish that comes from diagnoses that are missed or come too late. Dermatologists can now identify patients with a high likelihood of BAP1 cancer syndrome through family history and total body skin examinations for the presence of possible MBAITs.
Written by Jay Martin, M.D.
Source: Haugh, et al. “Genotypic and Phenotypic Features of BAP1 Cancer Syndrome: A Report of 8 New Families and Review of Cases in the Literature.” JAMA Dermatology. doi:10.1001/jamadermatol.2017.2330. Published online 9 August 2017.