Task: Instance Description Understanding (ontology: Sciences/Computer_Science)

Which of the following definitions best describes the instance 'pTis (lung)'?

A. A pathologic primary tumor stage for lung according to AJCC 7th edition indicating that the tumor of any size that invades any of the following: mediastinum, heart, great vessels, trachea, recurrent laryngeal nerve, esophagus, vertebral body, carina or there is separate tumor nodule(s) in a different ipsilateral lobe to that of the primary.
B. A pathologic primary tumor stage for lung according to AJCC 7th edition indicating that the tumor is more than 5 cm but not more than 7 cm in greatest dimension.
C. A pathologic primary tumor stage for lung according to AJCC 7th edition indicating that there is no evidence of primary tumor.
D. A pathologic primary tumor stage for lung according to AJCC 7th edition indicating carcinoma in situ.

Answer: A pathologic primary tumor stage for lung according to AJCC 7th edition indicating carcinoma in situ.