Stage II Pleural Diffuse Malignant Mesothelioma AJCC v9

**Semantic type:** Neoplastic Process

**Definition:** Stage II includes: (T2, N0, M0); (T1, N1, M0). cT1: Tumor limited to the ipsilateral parietal pleura with Psum 12 mm or less and no involvement of the fissure (Fmax 5 mm or less). Note: Psum: pmax1+pmax2+pmax3 (sum of 3 measurements of maximal pleural thickness measured on axial images along the chest wall or mediastinum in each of the three divisions of the chest - upper, middle and lower divided by two lines; one at the top of the aortic arch and the second drawn at the top of the left atrium). Fmax: maximal thickness of pleural tumor along the fissures measured on sagittal images. pT1: Tumor limited to the ipsilateral parietal pleura with no involvement of the fissure. cT2: Tumor involving the ipsilateral pleura with Psum 12 mm or less, and with any of the following: involvement of the fissure (Fmax more than 5 mm); mediastinal fat invasion; solitary area of chest wall soft tissue invasion; or tumor involving the ipsilateral pleura with Psum more than 12 mm but equal to or less than 30 mm, with or without: involvement of the fissure (Fmax more than 5 mm); mediastinal fat invasion; solitary area of chest wall soft tissue invasion. pT2: Tumor involving the ipsilateral pleura and with any of the following: involvement of the fissure; ipsilateral lung parenchyma invasion; diaphragm (non-transmural) invasion. N0: No tumor involvement of regional lymph node(s). N1: Tumor involvement of ipsilateral bronchopulmonary, hilar, or mediastinal (including the internal mammary, peridiaphragmatic, pericardial fat pad, or intercostal lymph nodes) regional lymph nodes. M0: No distant metastasis. (AJCC 9th ed.)