CTCAE Grade 4 Pharynx Stricture or Stenosis

Life-threatening consequences; operative intervention with thoracoplasty, chronic open drainage or multiple thoracotomies indicated

Life-threatening airway compromise; tracheotomy or intubation indicated

Life-threatening consequences; operative intervention requiring complete organ resection (e.g., total colectomy)

Symptoms associated with life-threatening consequences

Tissue necrosis; significant spontaneous bleeding; life-threatening consequences