Guillain-Barre Syndrome Amid Osteosarcoma Treatment: A Therapeutic Dilemma and Literature Review.

Guillain-Barre syndrome (GBS) is a clinical syndrome with multiple variants. GBS is defined as an acute demyelinating polyneuropathy commonly preceded by infection (bacterial or viral), trauma, or inflammatory processes, which triggers an autoimmune response that affects the peripheral nervous system. This case report describes a patient with high-grade osteosarcoma that completed neoadjuvant chemotherapy and underwent surgical resection with no immediate complications. Fourteen days after the surgery, the patient developed an acute inflammatory demyelinating polyradiculopathy consistent with GBS. As the five-year survival without chemotherapy is only around 20%, this challenging clinical scenario raised questions regarding adjuvant chemotherapy's safe completion in this setting.