Ewing Sarcoma of the Pelvis in a Young Woman

Purpose: The goal of this project is to improve the management and clinical decision making for patients with Ewing sarcoma. It is also a goal to explore opportunities for earlier diagnoses, which could enhance treatment outcomes. Ewing sarcoma is a malignant tumor most often arising in the medullary cavity of bones and with greatest frequency in the pelvis, femur, and humerus. These patients present with pain at the site of the tumor, but there is often a delay in diagnosis that results in a more difficult course of treatment. The current 5-year survival rate is 75% with long-term cure rate of 50%. The outlook is worse for adolescent and young adult (AYA) patients, especially those with evidence of metastasis at diagnosis. Methods: A retrospective analysis of this patient’s medical history and treatment as it pertains to Ewing sarcoma was conducted. Results: A healthy 18-year-old female presented to her family physician 10 months after the initial onset of hip pain with the chief complaint of constipation and general abdominal discomfort. The pain was progressively worsening and began to radiate down her anterior right thigh. It was exacerbated with exercise, walking, sitting, and caused difficulty sleeping. It was alleviated with bending forward and lying down. There were no reports of numbness, tingling, muscle weakness, or other symptoms in the right leg. On physical exam, her family physician palpated a mass in the right lower quadrant, which was confirmed by ultrasound to be approximately 12cm in diameter. A pelvic MRI confirmed a 9.2 x 13.9 x 12cm soft tissue mass of the right ileum. After 8 weeks of chemotherapy, the tumor showed a significant decrease in size, and she received proton-beam radiation therapy at 14 weeks. On six occasions, chemotherapy had to be delayed by one week to allow for platelet or white blood cell count recovery. At the conclusion of her chemotherapy regimen, the patient was considered to be cancer-free, in remission, and began off-therapy surveillance. This case is significant because it assesses the importance of a prompt diagnosis in the outcome of Ewing sarcoma patients, and the difficulties that can arise during a compressed interval treatment. Conclusions: Despite the large period of time between onset of symptoms and diagnosis, the combination of chemotherapy and radiation achieved a remission. It will be important to follow this patient closely to monitor for risk of relapse and late effects of cancer treatment.