Unfortunately, cancer has hit too close to home for many. If you haven't personally been affected by cancer, odds are you have a family member, friend or colleague who has battled this disease.
Despite cancer's prevalence, cancer and its terminology still causes confusion. Stage I cancer, tumor grades and metastasis are terms discussed but rarely defined.
Breaking Down the Facts
Understanding cancer staging and diagnosis hinges on firmly grasping the TNM staging system, where each letter in the acronym stands for an important component of staging:
- T-size of the primary tumor
- N-any possible spreading of the cancer to lymph nodes
- M-occurrence of metastasis-a state in which the cancer has moved to other body parts
Assigned numbers to these letters allow physicians to stage cancers.
- TX-tumor can't be assessed
- T0-no evidence of tumor can be found
- Tis-carcinoma in situ or CIS (Abnormal cells exist but haven't spread deeper into tissue. Though not categorized as cancer, CIS can develop into cancer).
- T1, T2, T3 and T4-given to define tumor size and possible spreading to nearby tissue
- NX-lymph nodes can't be assessed
- N0-no evidence of cancer in lymph nodes
- N1, N2 and N3-amount of lymph nodes affected and the severity of spreading
- MX-metastasis can't be assessed
- M0-no evidence of metastasis
- M1-metastasis has occurred
Physicians may also look at tumor grade (evaluation of cancer cells to determine how much they differ from healthy cells). The more abnormal the cells appear, the more quickly they spread. After analyzing the cancer, physicians tally the findings and categorize the cancer into one of five stages:
- Stage 0-CIS
- Stage I, II and III-Higher stages denote larger tumors and more extensive spreading to lymph nodes or nearby organs
- Stage IV-Cancer has spread to other parts of the body