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Minimal Role of Radio-Imaging
Interestingly, radiographic imaging (CT scan, MRI, X-ray) is usually not useful in the detection of vocal
fold atypia or early cancer, because these imaging techniques do not
currently provide enough detail and resolution of these early lesions.
However, radiographic imaging can be helpful in detecting the spread of
cancer to other body locations such as the lungs, head, and neck.
Typical Findings of Vocal Fold Atypia and Early Cancer
| Finding |
Description |
Likely Diagnosis |
White Lesions
(keratosis or leukoplakia) |
A white, rough, irregular lesion on the surface of the vocal folds |
95% Atypia |
Red Lesions
(erythroplakia) |
A reddish, rough, irregular lesion on the surface of the vocal folds |
Carcinoma in-situ |
Papular Red Lesions |
Reddish lesions with small "bubbles" on surface |
Carcinoma in-situ |
Exophytic Lesions |
Irregular lesions that stick outwards from the vocal folds |
Usually advanced cancer
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Classifying Atypia and Early Cancer
The three main aspects of early vocal fold cancer that are helpful in determining treatment plans are:
- Location of lesion
- Effect on vocal fold (arytenoids) mobility
- Effect on mucosal vibration
If the lesion is cancerous, the first two characteristics will determine the stage of disease.
Location and Depth of the Lesion
- One-sided or both vocal folds affected: The
most important issue with regard to the location of early vocal fold
cancer is whether it is present on one or both vocal folds. The number
of vocal folds involved has greater impact than the size of the lesion
on the treatment outcomes for early cancer.
- Spread to anterior commissure tendon: One specific aspect of spread pertinent to treatment is whether a lesion has traveled into the anterior commissure tendon (Broyle's ligament).
This ligament forms a bridge between the vocal folds. In general,
bilateral cancers do spread onto this tendon as they pass over onto the
second vocal fold. If this tendon is involved, physicians must
determine whether further spread (for example, into the thyroid
cartilage) has occurred.
- Cancer spread determines treatment plans: The extent of cancer spread determines the treatment plan for a
patient. Fortunately, through advances in microsurgical techniques and
radiation therapy (XRT), early cancer lesions that have spread to
different points within the larynx can be treated with 90 to 95 percent
effectiveness.
Effect of a Lesion on Vocal Fold Mobility
Not surprisingly, a lesion that invades a vocal fold deeply or spreads to the cricoarytenoid joint can prevent vocal fold movement. (For more information, see Anatomy & Physiology of Voice Production.)
Effect on Ability of Vocal Folds to Vibrate
Even if restricted to the top layers of the vocal folds, atypia and
early cancer result in poor vocal fold vibratory function, hence voice
disorder. This is not surprising given that the vocal fold mucosa –
which is composed of the epithelium and superficial lamina propria – is
a key player in vocal fold vibration. Abnormalities in vocal fold
vibration result in hoarseness and other voice symptoms.
Additionally, swelling that often accompanies early cancer hinders vocal fold vibration.
Diagnosis by Microscopic Analysis
The only true method to determine whether a lesion is atypia or
cancerous is to excise all or part of the growth and perform a
microscopic analysis of the lesion's cellular characteristics. Visual
examination of the lesions on the surface does not allow a definitive
diagnosis.
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