Cristina undergoes a biopsy of a suspicious lesion. The biopsy report classifies the lesion according to the TNM staging system as follows: TIS, N0, M0. What does this classification mean?
A. No evidence of primary tumor, no abnormal regional lymph nodes, and no evidence of distant metastasis.
B. Carcinoma in situ, no abnormal regional lymph nodes, and no evidence of distant metastasis.
C. Can’t assess tumor or regional lymph nodes and no evidence of metastasis.
D. Carcinoma in situ, no demonstrable metastasis of the regional lymph nodes, and ascending degrees of distant metastasis.
Correct Answer: B. Carcinoma in situ, no abnormal regional lymph nodes, and no evidence of distant metastasis
TIS, N0, M0 denotes carcinoma in situ, no abnormal regional lymph nodes, and no evidence of distant metastasis.
Option A: No evidence of primary tumor, no abnormal regional lymph nodes, and no evidence of distant metastasis is classified as T0, N0, M0.
Option C: If the tumor and regional lymph nodes can’t be assessed and no evidence of metastasis exists, the lesion is classified as TX, NX, M0.
Option D: A progressive increase in tumor size, no demonstrable metastases of the regional lymph nodes, and ascending degrees of distant metastasis is classified as T1, T2, T3, or T4; N0; and M1, M2, or M3.