T-Cell Lymphoblastic Lymphoma Presenting as Acute Clavicular Pain

An anterior mediastinal mass has a broad differential. We report a case of a large anterior mediastinal malignancy in a pediatric patient presenting with left-sided supraclavicular pain without symptoms of cardiopulmonary compromise. The mass was revealed with CT imaging and diagnosis of T-cell lymphoblastic lymphoma was confirmed after supraclavicular lymph node biopsy. The patient was initially treated with methylprednisolone for cytoreduction and a combination of rasburicase and allopurinol for asymptomatic tumor lysis syndrome. There was then a 34-day induction phase of chemotherapy with vincristine, daunorubicin, PEG-asparaginase, and intrathecal methotrexate. CSF sampling and bone marrow biopsies were both negative at the end of induction. The patient is currently in the consolidation phase, taking cyclophosphamide, cytarabine, and 6-MP, and is tolerating the treatment well.