Patient Case Discussion
Case Summary
Neuroblastoma with Skeletal Involvement
The surgical team discussed the abnormal images of bilateral shoulders, femurs, and humerus that showed a primitive appearance to the proximal humerus metaphysis and a subtle periosteal reaction. The right femur also showed a permeative, "moth-eaten" pattern of the distal femoral metaphysis. These findings were concerning for osteomyelitis or occult pathological fracture. A whole body MRI revealed a voluminous suprarenal mass with multiple lymph nodes and extensions within the retroperitoneum. The MRI also showed involvement of multiple cranial bones, left humerus, proximal femur, and diffuse bone marrow involvement in the spine and pelvis. An MIBG nuclear medicine scan confirmed involvement of the whole or most of the skeleton, with a focal mass in the right suprarenal region. The findings were suggestive of neuroblastoma.
Neuroblastoma Diagnosis and Treatment Discussion
The sugical team discussed the challenges of obtaining a tissue diagnosis for a neuroblastoma case, suggesting a laparoscopic biopsy as the best option because of the tumor's location and risk of bleeding. They also mentioned a recent Children's Oncology Group protocol that randomized patients to either standard chemotherapy or chemotherapy with Dinituximab, an anti-GD2 antibody, added early in therapy. The team then proceeded to discuss the patient's pre-operative imaging after chemotherapy.
Right Suprarenal Mass Treatment Discussion
The group discussed the significant decrease in size of a right suprarenal mass and disappearance of multiple adenopathies following treatment. They debated the merits of image-guided core biopsy versus laparoscopy, considering factors such as tissue requirements for molecular testing and potential risks. The resected tumor, weighing 7.1 grams, showed a dramatic response to chemotherapy with >95% maturation and cytodifferentiation. The pathology report indicated a positive outcome for the patient, with the tumor's appearance changing from poorly differentiated neuroblastoma to mostly differentiated neuroblasts and Schwannian stroma.
Neuroblastoma Risk Factors and Prognosis
The surgical team discussed the factors that determine a patient's risk category in neuroblastoma, particularly focusing on the biological behavior of the tumor. They discussed the importance of factors such as MycN, 11q, and L2 in determining high-risk categories. The team also discussed the impact of pathology results on patient prognosis and further treatment. A good end of induction response leads to consolidation with high-dose chemotherapy and auto stem cell rescue, while a poor response leads to an extended induction protocol. The team also discussed challenges in obtaining tissue samples for diagnosis, particularly in infants, and the potential use of bone marrow or skin lesions for biopsy. The conversation ended with a discussion on the minimum tissue volume required for diagnostic molecular testing.