SG05 The use of oral methotrexate in a case of Ferguson–Smith syndrome

Abstract A 47-year-old woman with genetically confirmed Ferguson–Smith syndrome (TGFBR1 pathogenic variant) presented with recurrent, painful keratoacanthoma-like lesions on her nose, face and ears, significantly impacting her quality of life. This case was challenging as the patient’s nose was severely affected, with prior perineural involvement and nonhealing lesions, resulting in significant scarring, pain and disfigurement. Despite 3 years of acitretin therapy, surgical excisions, imiquimod and repeated cryotherapy, the lesions remained poorly controlled. Her medical history included psoriasis, vestibular schwannoma, trigeminal neuralgia and right-eye blindness. Her sister, also diagnosed with Ferguson–Smith syndrome and psoriatic arthritis, achieved complete remission of similar skin eruptions after initiation of oral methotrexate for arthritis. Given the shared history in both siblings, our patient was started on oral methotrexate. Within 4 weeks of treatment, her condition showed significant improvement, with control of both facial lesions and concurrent psoriasis. Ferguson–Smith syndrome, first described in 1971, is a rare inherited condition characterized by multiple self-healing squamous epitheliomas. These lesions, while typically resolving spontaneously, often result in scarring. Intralesional methotrexate is a recognized treatment for keratoacanthomas; however, oral methotrexate has shown limited efficacy in similar syndromes of multiple keratoacanthomas. This case, along with her sister’s experience, highlights oral methotrexate as a potential therapeutic option for refractory cases. Further studies are needed to explore its role in the management of this challenging condition.