En bloc resection is a surgical procedure aiming to remove a tumor mass in its entirety, fully covered by a continuous shell of healthy tissue. Oncological indications for this procedure are aggressive benign tumors (Enneking stage 3), like osteoblastoma and giant-cell tumor, and low-grade malignant tumors (Enneking stage IA and B), like chordoma and chondrosarcoma. In high-grade malignant tumors like osteosarcoma and Ewing sarcoma, en bloc resection must be combined with protocols of chemotherapy and radiotherapy (RT) in a multidisciplinary approach. En bloc resection can be an option in selected single metastases originating from tumors resistant to chemotherapy and radiation protocols, once the criteria of feasibility are fulfilled without functional sacrifices. The criteria of feasibility of tumor-free margins in the lumbar spine include one pedicle free from tumor and a part of the posterior arch allowing room to release the thecal sac. The Weinstein-Boriani-Biagini (WBB) staging system can be helpful in providing standardized strategies according to tumor extension and location. A strong consideration of the role of margins in the local and systemic prognosis can include in the en bloc resection even relevant anatomical structures (nerve roots, dura, arteries, and veins) when they are infiltrated by the tumor or are running along the tumor margins.
KeywordsSpine tumor Lumbar spine En bloc resection Spondylectomy Surgical technique WBB staging system Enneking staging system
It would not have been possible to conceive and finalize this chapter without the collaboration of Carlo Piovani. His work as an archivist and his original drawings are absolutely invaluable.
The steps of the resection (M4V 40379 kb)
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