PAX3-NCOA1 alveolar rhabdomyosarcoma of the tongue: A rare entity with challenging diagnosis and management

Alveolar rhabdomyosarcoma (ARMS) is associated with PAX3/PAX7-FOXO1 fusion, which confers specific clinic and biologic characteristics with inferior outcomes. A minority of tumors still histologically classified as true ARMS lack the canonical PAX-FOXO1 fusion but have new molecular alterations. We present the first case of PAX3-NCOA1 ARMS with clinical data and follow-up in a two-year-old girl with ARMS of the tongue and nodal extension, treated with chemotherapy, hemi glossectomy, lymph node dissection, and brachytherapy to conserve oral function and limit long-term sequelae. Given the rarity of such variant fusion in ARMS, international collaboration is required to evaluate its prognostic value.

Automated summary

Alveolar rhabdomyosarcoma (ARMS) is commonly associated with PAX3/PAX7-FOXO1 fusion gene, but some tumors without this fusion may have new molecular alterations. A rare case of PAX3-NCOA1 ARMS in a two-year-old girl with tongue and nodal extension was treated with a combination of therapies to preserve oral function and minimize long-term effects. International collaboration is necessary to evaluate the prognostic value of this variant fusion in ARMS.