The TNM classification for cervical cancer is a way to stage the disease based on specific criteria relating to the size and extent of the primary tumor, lymph node involvement, and the presence of distant metastasis. When using this calculator, the user is asked to select from predefined options for each of these criteria:

1. Tumor classification options describe the depth of stromal invasion and the greatest dimension of the invasive carcinoma, ranging from:
   - Tx: Primary tumor cannot be assessed
   - T0: No evidence of primary tumor
   - T1a1 to T1b3: Varying depths and sizes of stromal invasion
   - T2a1 to T2b: Tumor extent and parametrial invasion
   - T3a to T4: Tissue involvement extending to adjacent organs

2. Lymph node classification reflects whether and where cancer has metastasized in the lymphatic system:
   - Nx: Regional lymph nodes cannot be assessed
   - N0: No regional lymph node metastasis
   - N0(i+): Isolated tumor cells present
   - N1: Metastases to pelvic lymph nodes
   - N2: Metastases reaching para-aortic lymph nodes

3. Distant metastasis options signify whether the cancer has spread beyond the pelvic region:
   - M0: No distant metastasis
   - M1: Presence of distant metastasis

By examining which conditions are fulfilled—using a logical structure—the cancer stage is derived, with each stage reflecting increasing severity of the disease. It considers combinations of conditions from these classifications to determine the stage. Here is a breakdown of possible stages:

- Stage IA1/IA2: Small stromal invasions (≤5mm in depth) without lymph node involvement or distant spread.
- Stage IB1/IB2/IB3: Larger tumors (up to >4 cm in diameter) without significant spread.
- Stage IIA1/IIA2/IIB: More advanced local cervical invasion, potentially affecting the upper vagina or parametria.
- Stage IIIA/IIIB: Tumor expansion to involve the lower vagina or the pelvic wall.
- Stage IIIC1/IIIC2: Clearly involves lymph node metastasis, either pelvic (IIIC1) or para-aortic (IIIC2).
- Stage IVA: Involvement extends to bladder or rectal mucosa, demonstrating local organ invasion.
- Stage IVB: Signifies confirmed distant metastasis, indicating the most advanced cancer stage.

These stages provide a comprehensive understanding of the cancer’s progression based on TNM classifications and are crucial for planning treatment and determining prognosis.

The TNM classification for cervical cancer is a clinical staging system developed by the American Joint Committee on Cancer (AJCC). It is designed for the stratification of patients with cervical cancer based on the extent of the disease, which is crucial for treatment planning and prognosis estimation.

The primary components of this classification system include the size and extent of the primary tumor (T), the involvement of nearby lymph nodes (N), and the presence of distant metastasis (M). Each of these components is assigned a numerical value, with higher numbers indicating a more advanced stage of the disease. 

The T category is determined by the size of the primary tumor and its extent of invasion into the surrounding tissues. The N category is based on the number and location of lymph nodes involved, while the M category indicates the presence or absence of distant metastasis. 

The final TNM stage is determined by combining the T, N, and M categories, providing a comprehensive picture of the disease's extent. This classification system aids in the selection of appropriate treatment strategies and provides valuable prognostic information.