Stage IVB Lung Cancer AJCC v9

**Semantic type:** Neoplastic Process

**Definition:** Stage IVB includes: (Any T, Any N, M1c1); (Any T, Any N, M1c2). M1c1: Multiple extrathoracic metastases in a single organ system. Note: For example, the skeleton is considered one organ. Several metastases in a single bone or several metastases in several bones are classified as M1c1. M1c2: Multiple extrathoracic metastases in multiple organ systems. (AJCC 9th ed.)