A Case of Osteosarcoma in Concurrent Sickle Cell Disease

Background: Osteosarcoma is an aggressive bone cancer with a poor prognosis. When this disease is coupled with a concurrent diagnosis of Sickle Cell Disease (SCD), very careful management of the treatment is necessary, due to complications that may arise. This case study will explore some of the complications that were faced in a patient with these two diseases. Case Information: An 11-year-old male with SCD presented to the hospital with leg pain. He was mistakenly believed to have osteomyelitis, a known complication of SCD. Imaging supported this initial diagnosis but further evaluation was ordered. A biopsy of the proximal tibia showed pleomorphic malignant cells and malignant osteoid, confirming a diagnosis of osteosarcoma. Treatment following the Children’s Oncology Group Protocol: AOST0331 was initiated. This protocol includes 29 weeks of chemotherapy consisting of alternating Methotrexate (MTX) once a week for two weeks, followed by Doxorubicin/Cisplatin one week. This is repeated until week 10, when a surgical resection of the tumor is performed, followed by 17 more weeks of chemotherapy. During treatment, several incidents that are attributable to complications of SCD occurred. Two instances of delayed MTX clearance and the formation of two intra-cardiac thrombi were the most troubling of these complications. The patient remained in the hospital during the prolonged MTX clearance, and was monitored closely until clearance was achieved. The patient also received tPA and Lovenox to dissolve the intra-cardiac thrombus and reduce the likelihood of the formation of another thrombus. Conclusions: SCD with a diagnosis of osteosarcoma presents unique challenges to a physician. SCD induces a hypercoagulable state and often leads to end-organ damage, and osteosarcoma is a cancer that must be dealt with aggressively to achieve remission. A diagnosis of osteosarcoma in a patient who already has SCD has the potential to be masked by the complications of SCD. Osteosarcoma must be considered a differential in someone who presents with bone pain, even if they are already known to have SCD. Once a diagnosis of osteosarcoma is made, the implications of the concurrent diagnosis of SCD requires that physicians very carefully consider the possibilities of severe complications that may arise. Managing physicians must have awareness of the effects chemotherapy can have on an individual that is both in a hypercoagulable state and may also have end-organ damage.