Diagnosis and Staging
For an oncologist to diagnose a tumor as Adenoid Cystic Carcinoma (ACC), they must run a few tests. The main types of tests for ACC are physical tests, imaging tests, and biopsies. For a quick physical test, the doctor will feel the location of the tumor or check for abnormalities that could have been caused by cancer. Imaging testing is an umbrella term for MRI, CT, and PET scans. Magnetic Resonance Imaging (MRI) uses magnets and radio waves to produce an image of the patient’s body. In preparation for some MRIs, a contrast dye called gadolinium will be injected into a vein to help the MRI pick up on the structures of the body clearer. The patient will then lie on a table to go into the MRI machine, a large tube open on both ends with a magnet surrounding it. During the scan, the machine might start to make a thumping-like sound. This is just the sound of the machine generating the energy to create the image.
A computerized tomography (CT) scan takes multiple X-ray images from different angles. A computer will then take those images to create cross-sectional images of the inner workings of the body. Similar to the MRI, a contrast dye will be administered in some cases. It can be through the mouth, a vein, or an enema. CTs are painless and only take about half an hour
A positron emission tomography (PET) scan detects radioactive sugar injected into a patient’s body. The sugar is absorbed by the cells that use the most energy, and cancerous cells use more energy than other body cells. The scan will pick up on the radioactive sugar and where the sugar is in the body. This means that the PET scan shows the energy-consuming, malignant cells in the patient’s body.
Once all results are back, the doctor will be able to assess and stage the particular case of ACC. Staging is important to develop a treatment plan best suited for the patient. A stage is a way to categorize the tumor’s growth or spread. The TNM system is used to stage ACC. The T stages tumors in the salivary glands; the N is for tumors in the lymph nodes, and the M is for any tumors that metastasized to a different part of the body. The following outlines of the TNM system are from cancer.net
TX: The primary tumor cannot be evaluated.
T0 (T plus zero): No evidence of a tumor is found.
T1: The tumor is small, 2 centimeters (cm) at its widest dimension. It is also noninvasive, which means it has not grown outside the area where it began.
T2: The tumor is larger, between 2 cm and 4 cm, but noninvasive.
T3: The tumor is larger than 4 cm, but not larger than 6 cm, and has spread beyond the salivary gland. However, the tumor does not affect the seventh nerve, which is the facial nerve that controls such expressions as smiles or frowns.
T4a: The tumor has invaded the skin, jawbone, ear canal, and/or facial nerve.
T4b: The tumor has invaded the skull base and/or the nearby bones and/or encases the arteries.
NX: The neck has undergone an intervention that prevents the evaluation of lymph nodes.
N0: There is no evidence of cancer in the regional nodes.
N1: The cancer has spread to a single node on the same side as the primary tumor, and the cancer found in the node is 3 cm or smaller.
N2a: The cancer has spread to a single lymph node on the same side as the primary tumor and is larger than 3 cm, but not larger than 6 cm.
N2b: The cancer has spread to more than one lymph node on the same side as the primary tumor, and no tumor measures larger than 6 cm.
N2c: The cancer has spread to more than one lymph node on either side of the body, and no tumor measures larger than 6 cm.
N3: The cancer found in the lymph nodes is larger than 6 cm.
MX: Distant metastasis cannot be evaluated.
M0: The cancer has not spread to other parts of the body.
M1: The cancer has spread to other parts of the body.
After the individual categories have been staged, they are combined to find the overall stage of the individual’s ACC. This chart is also from cancer.net
Stage I: This stage describes a noninvasive tumor (T1 or T2) with no spread to lymph nodes (N0) and no distant metastasis (M0).
Stage II: This stage describes an invasive tumor (T3) with no spread to lymph nodes (N0) or distant metastasis (M0).
Stage III: This stage describes a smaller tumor (T1 or T2) that has spread to regional lymph nodes (N1) but shows no sign of metastasis (M0).
Stage IVA: This stage describes any invasive tumor (T4a) that either has no lymph node involvement (N0) or has spread to only a single, same-sided lymph node (N1), but with no metastasis (M0). It is also used to describe a T3 tumor with one-sided nodal involvement (N1) but no metastasis (M0), or any tumor (any T) with extensive nodal involvement (N2) but no metastasis (M0).
Stage IVB: This stage describes any cancer (any T) with more extensive spread to lymph nodes (N2 or N3) and no metastasis (M0).
Stage IVC: This stage describes any cancer (any T, any N) with distant metastasis (M1).