Introduction/Background Alveolar soft part sarcoma (ASPS) of the cervix is a rare mesenchymal tumour. Due to its rarity and paucity of definitive guidelines, diagnosis and management, especially during adolescence can be challenging.

Methodology We describe a case of a 13-year-old girl who presented with abnormal uterine bleeding and a broad ligament mass. Pelvic ultrasound showed a 3.9cm heterogeneous mass in the right cervical wall, mimicking a cervical fibroid. On MRI pelvis, this vascular mass, was suspected to be an atypical cellular leiomyoma. Diagnostic laparoscopy and biopsy of the pelvic mass showed a circumscribed lesion adjacent to cervix. The morphologic features and TFE3 positivity by immunohistochemistry raised the differential diagnoses of PEComa(perivascular epithelioid cell tumour), Epithelioid haemangioendothelioma or alveolar soft part sarcoma. Molecular testing with Archer fusionplex pan-solid tumour panel showed ASPSCR1 (exon 7)::TFE3 (exon 6) and TFE3 (exon 5):: ASPSCR1 (exon 8) gene fusions. A laparotomy, vaginoscopy and surgical resection of the tumour enabled confirmation of final diagnosis as ASPS of the cervix.

Results Currently, there is no consensus regarding the optimal management of this rare neoplasm. ASPS is an indolent tumour but prone to metastasis especially to lungs and brain. Surgical excision with clear margins, often via hysterectomy, is the treatment of choice. However, this can be associated with significant morbidity and loss of fertility potential in adolescents. The role of adjuvant radiotherapy is usually for high-grade tumours and close margins. The role of adjuvant chemotherapy is unclear. Targeted therapies with multi target tyrosine kinase inhibitors may be considered for selected cases.

Conclusion ASPS of the cervix is a rare entity with propensity to metastasize. Early diagnosis and surgical resection with clear margins are important for a more favourable prognosis.

Disclosures Nil