Features of multiple self-healing squamous epithelioma and Loeys-Dietz syndrome in a patient with a novel TGFBR1 variant

Coexistence of multiple self-healing squamous epithelioma and features of Loeys-Dietz syndrome caused by a pathogenic missense variant in the kinase domain of TGFBR1

Multiple self-healing squamous epithelioma (MSSE) is characterized by development of multiple self-healing skin tumours that may affect any part of the body. Spontaneous resolution may take several months leaving pitted scars. Most pathogenic variants in patients with MSSE are truncating variants distributed throughout the gene or missense variants in the receptor domain of TGFBR1. Missense variants in the kinase domain of TGFBR1 cause Loeys–Dietz syndrome (LDS), which is a connective tissue disorder associated with increased risk of aortic and arterial aneurysms and dissection. We report the coexistence of MSSE and features of LDS caused by a pathogenic missense variant in the kinase domain of TGFBR1.

Multiple Self-Healing Squamous Epithelioma (MSSE): A Digenic Trait Associated with Loss of Function Mutations in TGFBR1 and Variants at a Second Linked Locus on the Long Arm of Chromosome 9

MSSE (Ferguson-Smith disease) is a rare familial condition in which multiple skin tumors resembling squamous carcinomas invade locally and then regress spontaneously after several months, leaving disfiguring scars. We review evidence from haplotype studies in MSSE families with common ancestry that the condition is caused by loss of function mutations in TGFBR1 interacting with permissive variants at a second linked locus on the long arm of chromosome 9. The spectrum of TGFBR1 mutations in MSSE and the allelic disorder Loeys Dietz syndrome (characterized by developmental anomalies and thoracic aortic aneurysms) differ. Reports of patients with both MSSE and Loeys Dietz syndrome are consistent with variants at a second locus determining whether self-healing epitheliomas occur in patients with the loss of function mutations found in most MSSE patients or the missense mutations in the intracellular kinase domain of TGFBR1 that characterize Loeys Dietz syndrome.