ID #253 Malignant transformation of craniopharyngioma: A rare presentation of metastatic disease
Kathleen Felton, Vijayananda Kundapur, Roland Auer, Viktor Zherebitskiy, Julia RadicAbstract
Background
Malignant craniopharyngioma, de novo or via malignant transformation, is a rare entity with unclear pathogenesis. It has a dismal prognosis and unclear treatment standards. We report a case of malignant transformation of craniopharyngioma with disseminated disease throughout the craniospinal axis and metastases to the lungs.
Results
The patient is a 17-year-old male, diagnosed with craniopharyngioma at 22 months of age, with a history of focal radiation (5040cGy) at 9 years of age and multiple surgeries. At 16 years of age, routine imaging demonstrated asymptomatic, local progression and he was initiated on trametinib. Unfortunately, after less than 1 month on therapy he had clinical and radiographic progression, confirmed by pathology to be craniopharyngioma WHO Grade 1. Trametinib was discontinued and he proceeded to focal re-irradiation (5400cGy). While receiving radiation he developed weakness of right hand/arm/leg. Imaging demonstrated metastatic disease to C2 and C7 with pathological fractures, spinal cord compression and innumerable lung metastases. He underwent urgent spinal decompression. Pathology of the C7 vertebral lesion demonstrated malignant transformation, molecluar testing of this lesion demonstrated a gain of function mutation, CTNNB1:p.S33C. No new molecular alterations were identified when comparing original pathology and malignant transformation specimens. He completed radiation to the spine C1 to T1 (3000cGy) along with 2 cycles of vincristine/cyclophosphamide. He had spinal, sellar, lung disease stability, but developed progressive left orbital/sinus disease, subsequently treated with radiation (2000cGy). Treatment continued with 6 cycles of carboplatin/paclitaxel, with an interval of disease stability. Unfortunately, he died due to disease progression, 13 months post malignant transformation.
Conclusion
Malignant transformation of craniopharyngioma is a rare occurrence and this is one of the first documented cases with metastatic disease. Evaluation of the craniospinal axis and whole body may be considered for workup of patients with craniopharyngioma presenting with rapidly progressive clinical symptoms and/or radiographic disease.